Marte Lie Høivik

• Molinaro, Antonio; Braadland, Peder Rustøen; Carpino, Guido; Carreras, Alba; Nikolaidis, Marios & Hanzely, Petra [Show all 40 contributors for this article] (2026). Gut microbiota-derived imidazole propionate promotes primary sclerosing cholangitis via p38 signalling. Nature Metabolism. 8(9), p. 1910–1925. doi: 10.1038/s42255-026-01600-1. Full text in Research Archive Show summary

  Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease of the bile ducts that can lead to biliary cancer and end-stage liver disease. PSC is associated with inflammatory bowel disease and an altered gut microbiota. However, the molecular mechanisms underlying gut–liver interactions in PSC remain poorly characterized. Here we show that the gut microbiota-derived metabolite imidazole propionate (ImP) is a disease driver in PSC. Individuals with PSC have higher circulating ImP levels than individuals with related conditions, and high ImP levels predict reduced survival in PSC. Cholangiocytes exposed to ImP show activated mammalian target of rapamycin complex 1 (mTORC1) signalling and secrete pro-inflammatory and pro-fibrogenic factors. Chronic administration of ImP to mice induces liver inflammation and fibrosis through a p38-dependent mechanism, upstream of mTORC1. We propose that chronic exposure to ImP induces cholangiocyte injury, which alone or in concert with other factors causes clinical worsening of PSC. Therefore, targeting ImP production or signalling may represent therapeutic avenues in PSC.

• Lindstrøm, Jonas Christoffer; Gjerdrum, Hilde Synnøve Vollan; Brynildsrud, Ola Brønstad; Tannæs, Tone Møller; Kristoffersen, Anja Bråthen & Ricanek, Petr [Show all 17 contributors for this article] (2026). Exploring alterations in the gut resistome in medically treated inflammatory bowel disease patients. BMC Microbiology. 26, p. 1–13. doi: 10.1186/s12866-026-05101-9. Full text in Research Archive
• Mahdy, Aya K.H.; Taheri, Zahra; Høivik, Marte Lie; Franke, Andre & ElAbd, Hesham (2026). High throughput profiling of the B cell repertoire identifies systematic changes in the repertoire of individuals with Crohn’s disease. Frontiers in Immunology. 17. doi: 10.3389/fimmu.2026.1725813. Full text in Research Archive
• Myhre, Anders Eivind; Meyer-Myklestad, Malin Holm; Gullaksen, Hanne Hestdal; Søgaard, Ole S.; Tolstrup, Martin & Salgado, Maria [Show all 51 contributors for this article] (2026). Long-term HIV-1 remission achieved through allogeneic haematopoietic stem cell transplant from a CCR5Δ32/Δ32 sibling donor. Nature Microbiology. 11, p. 1374–1386. doi: 10.1038/s41564-026-02304-8. Full text in Research Archive Show summary

  Only few cases of human immunodeficiency virus (HIV) remission have been reported after allogeneic haematopoietic stem cell transplantation (HSCT), mostly involving stem cell donors with the homozygous CCR5Δ32 (CCR5Δ32/Δ32) mutation, which confers resistance to CCR5-tropic HIV-1. Here we report the case of a 63-year-old man in off-treatment HIV remission, 5 years after HSCT with a CCR5Δ32/Δ32 sibling donor for myelodysplastic syndrome. In-depth clinical characterization including virological and immunological analyses of peripheral blood, gut and bone marrow samples revealed that full donor chimerism was achieved. Antiretroviral therapy was discontinued after 24 months, and 48 months after HSCT, no intact HIV DNA was detected in blood or gut biopsies. Replication-competent virus and HIV-specific T cell responses were absent, and HIV antibody responses showed a gradual decline. Full donor chimerism in the gut, which is the primary viral reservoir, underscores the likelihood of a cure.

• Hansen, Simen Hyll; Bhattacharjee, Niharika; Hu, Chang; Maseng, Maria Gjerstad; Grannö, Olle & Bang, Corinna [Show all 20 contributors for this article] (2026). Bacterial clusters are associated with the risk of severe disease progression in inflammatory bowel disease irrespective of conventional disease categories. Microbiome Research Reports. 5(1). doi: 10.20517/mrr.2025.96. Full text in Research Archive Show summary

  Background: Inflammatory bowel diseases (IBDs) are complex conditions marked by chronic inflammation in the gastrointestinal tract. Traditional classification separates IBD into Crohn’s disease and ulcerative colitis, but this division may not fully capture disease heterogeneity. Here, we examine whether microbiome-driven subtyping can describe novel clinical IBD phenotypes. To achieve this, we applied unsupervised clustering to fecal microbiota profiles from the population-based Inflammatory Bowel Disease in South-Eastern Norway III (IBSEN III) cohort. Methods: A Gaussian Mixture Model (GMM) was used to cluster participants with IBD based on microbiome composition and examine associations between clusters and clinical outcomes, including inflammatory markers and disease severity during the first year after inclusion. Results: Three microbiome-based clusters were identified: CLO (dominated by Clostridia UCG-014), ALF (Agathobacter, Lachnoclostridium, and Faecalibacterium), and RUM (Ruminococcus gnavus). Participants in the RUM cluster had a higher risk of future severe disease than those in the CLO cluster, even among participants with remission-to-mild disease at inclusion (21% vs. 6%, P < 0.00001). This association could not be explained by antibiotic use or baseline disease severity. Cluster membership alone performed comparably to fecal calprotectin in distinguishing severe disease, and a combined model significantly improved accuracy (P < 0.0001). Conclusion: Our findings demonstrate a connection between microbiome composition and the risk of severe disease development, which is partly independent of inflammation levels at the time of sampling. Microbiome-informed subgrouping could lead to more personalized treatment strategies. Further validation is needed to determine the clinical utility of these clusters.

• Maseng, Maria Gjerstad; Hansen, Simen Hyll; Grännö, Olle; Bang, Corinna; Lund, Charlotte & Huppertz-Hauss, Gert [Show all 22 contributors for this article] (2026). Disentangling the gut microbiome and inflammation in inflammatory bowel diseases: longitudinal observations from the IBSEN III study. Inflammatory Bowel Diseases. ISSN 1078-0998. doi: 10.1093/ibd/izag051. Full text in Research Archive Show summary

  Background and Aim Despite the well-established involvement of the gut microbiome in inflammatory bowel disease (IBD), less is known about how the gut microbiome changes over time and how it varies with clinical disease activity and fecal calprotectin (f-calprotectin). To address this gap, we utilized samples from the population-based inception cohort of the Inflammatory Bowel Disease in South-Eastern Norway III (IBSEN III) study. Methods Data and stool samples from study participants with IBD and symptomatic controls were collected at diagnosis and after 3, 6, and 12 months. Microbiome profiling of stool samples was performed targeting the V3-V4 region of the 16S rRNA gene, and a consensus-based approach of mixed models was employed for the longitudinal microbiome analysis. Results We included 1251 samples from 744 patients with ulcerative colitis, 618 samples from 356 patients with Crohn’ s disease and 266 samples from 164 symptomatic non-IBD controls. In the IBD population, we observed that levels of f-calprotectin decreased over time, as did the patient-reported disease activity (P < .001). Distinct changes in the gut microbiome of IBD patients were observed throughout the first year, such as increased alpha diversity (P < .001) and significant taxonomic changes. Notably, there was no covariation between the changes in alpha diversity and f-calprotectin or symptom score. Conclusion The gut microbiome during the first year after IBD diagnosis showed changes that paralleled inflammation and clinical disease activity, albeit without covariation, suggesting that there may be a disease-driving impact of gut microbiome independent of inflammation and inflammation-driven symptoms.

• Bergsmark, Camilla; Kristensen, Vendel Ailin; Sjåmo, Maren B.; Høivik, Marte Lie & Anisdahl, Karoline (2026). Therapeutic drug monitoring in inflammatory bowel disease patients switching from intravenous to subcutaneous infliximab: insights from a prospective real-world study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. doi: 10.1080/00365521.2026.2645083. Full text in Research Archive
• Mathisen, Charlotte Bache-Wiig; Nyström, Niklas; Bazov, Igor; Øyås, Ove; Zucknick, Manuela & Andersen, Svend [Show all 23 contributors for this article] (2026). A novel diagnostic serum protein signature for pediatric inflammatory bowel disease. Journal of Pediatric Gastroenterology and Nutrition - JPGN. ISSN 0277-2116. doi: 10.1002/jpn3.70379. Full text in Research Archive Show summary

  Abstract Objectives Diagnostic delay is common in pediatric inflammatory bowel disease (PIBD), and fecal calprotectin (FCP) is often limited by challenges with sample collection. Therefore, we aimed to identify and validate a blood‐based diagnostic protein signature of PIBD. Methods Proteins were analyzed using proximity extension assay in plasma samples from treatment‐naïve pediatric patients in a Swedish inception cohort referred for suspected inflammatory bowel disease (IBD) and validated in an independent Norwegian population‐based pediatric inception cohort. Diagnostic performance was estimated by the area under the curve (AUC) with 95% confidence intervals (CIs). Results The discovery cohort included 58 patients with PIBD and 36 symptomatic controls without evidence of IBD, while the validation cohort consisted of 79 patients with PIBD and 37 symptomatic controls. In total, 154 proteins were examined. Univariable analyses identified 26 differentially regulated proteins for PIBD versus symptomatic controls in the discovery cohort ( q  < 0.05), whereas 29 proteins were differentially regulated in the validation cohort. Using regularized logistic regression, we identified a diagnostic model of 31 proteins that differentiated PIBD from symptomatic controls in the discovery cohort (AUC = 0.83; 95% CI: 0.74–0.90). The protein signature was further reduced to a clinically relevant biomarker consisting of high‐sensitivity C‐reactive protein (hsCRP) and seven other proteins with diagnostic capacity (AUC = 0.85, 95% CI: 0.78–0.92) outperforming hsCRP in the validation cohort ( p  = 0.006). Conclusions We identified and validated a blood‐based protein signature for PIBD with superior diagnostic performance compared to hsCRP. Given the challenges of fecal sample collection, further assay development may enable integration of these biomarkers into diagnostic pathways for PIBD. Trial Registration ClinicalTrials.gov identifier: NCT02727959.

• Johansen, Ingunn; Hagen, Milada; Løkkeberg, Stine Eileen Torp; Aabrekk, Tone Bergene; Asak, Øyvind & Bengtson, May-Bente [Show all 22 contributors for this article] (2026). Anxiety and depression in newly diagnosed patients with inflammatory bowel disease (the IBSEN III study) compared with the general population in Norway. Journal of Crohn's and Colitis. ISSN 1873-9946. 20(3). doi: 10.1093/ecco-jcc/jjag021. Full text in Research Archive Show summary

  Background and Aims: Symptoms of anxiety and depression are common in inflammatory bowel disease (IBD); the aim of this study was to assess the proportion of anxiety and depression in patients newly diagnosed with IBD, compare the rates with the Norwegian general population (NGP), and examine associations with selected sociodemographic, psychological, and disease-related factors. Methods: This prospective cohort study included newly diagnosed patients with IBD, and data from the HUNT4 survey of the NGP. Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale. Crude statistical comparisons were performed using t-tests, Mann–Whitney U test, chi-square tests, or Fisher’s exact tests. Adjusted associations were modeled using multiple robust linear regression and multiple logistic regression. Results: In total, 938/1562 (62.1%) patients with IBD completed the Hospital Anxiety and Depression Scale (Crohn’s disease [CD]: n = 297, ulcerative colitis [UC]: n = 641). The proportion of anxiety was 37.4% in CD and 32.1% in UC, while depression was reported by 21.9% and 16.8%, respectively. Both rates were significantly higher than those observed in the NGP (17.5% for anxiety and 9.4% for depression). Compared with the NGP, males with CD had significantly higher levels of anxiety and depression, males with UC had elevated anxiety only, while females with CD and UC showed increased anxiety and depression. Both substantial fatigue and general self-efficacy were significantly associated with anxiety and depression in IBD. Conclusions: Newly diagnosed patients with IBD experienced significant psychological challenges compared with the NGP. Early identification of anxiety and depression may enable targeted interventions.

• Mahdy, Aya K. H.; ElAbd, Hesham; Kokubun, Érika Endo; Kriukova, Valeriia; Pesesky, Mitchell & May, Damon H. [Show all 24 contributors for this article] (2026). Multi-centered T cell repertoire profiling identifies alterations in the immune repertoire of individuals with inflammatory bowel disease across different disease stages. Genome Medicine. 18. doi: 10.1186/s13073-025-01575-w. Full text in Research Archive Show summary

  Abstract Background Inflammatory bowel disease (IBD) is an incurable immune-mediated inflammatory disease, affecting the gut with a high rate of primary- and secondary- loss-of-response to therapy. By investigating the T cell receptor repertoire of individuals with IBD, novel therapeutic and preventive strategies can be identified, and a better understanding of IBD can be obtained. Methods To identify and validate T cell clonotypes implicated in the pathogenesis of IBD, we profiled the T cell receptor alpha (TRA) repertoire of three cohorts containing treatment-naive, treated individuals, and individuals living with the disease for >20 years, resulting in an exhaustive dataset containing the TRA repertoire of 1,732 individuals. Results Using the generated datasets, we were able to replicate previous findings describing the expansion of Crohn’s-associated invariant T (CAIT) cells in individuals with Crohn’s disease (CD) in the three cohorts. Using a hypothesis-free statistical testing framework, we identified clonotypes that were associated with the disease at its different stages, e.g., at the time of diagnosis and decades post-diagnosis. By conducting a meta-analysis across the three cohorts, we were able to identify a set of clonotypes that were associated with the disease regardless of its stage. We validated our findings in a previously published independent test dataset from a German cohort, showing the robustness of the identified clonotypes. Conclusions The identified clonotypes are novel therapeutic targets to treat IBD, for example, through targeted depletion. By identifying antigens recognized by these T cells, a better understanding of the etiopathology of IBD, particularly CD, can be obtained.

• Holten, Kristina Ingeborg Aass; Bernklev, Tomm; Opheim, Randi; Olsen, Bjørn Christian Elias Grova; Johansen, Ingunn & Strande, Vibeke [Show all 19 contributors for this article] (2026). Fatigue Trajectory During the First Year of an Inflammatory Bowel Disease Diagnosis, Results from the IBSEN III study. Digestive Diseases and Sciences. ISSN 0163-2116. 71, p. 2476–2487. doi: 10.1007/s10620-025-09661-0. Full text in Research Archive Show summary

  Background: Fatigue is common in Crohn's disease (CD) and ulcerative colitis (UC), but the pathogenesis remains poorly understood. Aims: This study aimed to assess changes in fatigue prevalence during the first year after diagnosis and examine the association between disease course and substantial fatigue (SF) at the 1-year follow-up. Methods: Adults with newly diagnosed CD or UC were recruited from the population-based IBSEN III cohort. Fatigue was assessed at diagnosis and the 1-year follow-up using the Fatigue Questionnaire. Associations between SF at the 1-year follow-up and disease-related factors were quantified using multivariate logistic regression adjusted for sex, age and comorbidities. Results: In total, 596 patients were included (CD: 196, UC: 400). SF was present at both baseline and after one year of disease for 46.9% (n = 92/196) and 40.5% (n = 162/400) of patients with CD and UC, respectively. In CD, development of endoscopically non-passable stricture and/or surgically treated stricture within first year of disease (OR = 4.52, 95%CI [1.61;12.68]), self-reported flares since diagnosis (OR = 2.55, 95%CI [1.26;5.16]), female sex (OR = 3.12, 95%CI [1.53;6.37]) and comorbidities (OR = 4.05, 95%CI [1.89;8.69]) were independently associated with SF at the 1-year follow-up. In UC, SF was associated with current biological treatment (OR = 5.14, 95%CI [1.56;16.96]), increasing Mayo endoscopic score at the 1-year follow-up (OR = 1.54, 95%CI [1.01;2.35]), self-reported flares since diagnosis (OR = 2.66, 95%CI [1.24;5.72]) and female sex (OR = 2.20, 95%CI [1.06;4.57]). Conclusions: Fatigue frequently persists through the first year after IBD diagnosis. Clinical factors reflecting a more severe disease course were associated with SF one year after diagnosis in both CD and UC.

• Füchtbauer, Johannes D.; Brovkina, Olga; Sivickis, Kostas; Aalykke, Claus; Høivik, Marte Lie & Andersen, Vibeke [Show all 10 contributors for this article] (2025). Gut Mycobiome in Inflammatory Bowel Disease: A Systematic Review of Case-Control Studies. Inflammatory Bowel Diseases. ISSN 1078-0998. 31(11), p. 3213–3224. doi: 10.1093/ibd/izaf217. Full text in Research Archive Show summary

  Background The bacterial composition of the microbiome in inflammatory bowel disease (IBD) has been the focus of substantial interest. In contrast, the fungal part of the microbiome, the mycobiome, has only rarely been investigated—although anti-Saccharomyces cerevisiae antibodies, an antibody against fungal mannan, have been known for years as a biomarker for Crohn’s disease (CD), but not for ulcerative colitis (UC). Methods A systematic review of case-control studies on the human gut mycobiome in IBD was conducted using searches in EMBASE and MEDLINE. Results Twenty-seven studies, with a total of 1406 IBD patients and 1060 controls were identified. The differences in alpha diversity varied across studies and were related to geography, whereas differences in beta diversity between cases and controls were found in a large majority of the studies. Overall, the results were inconsistent at different taxonomic levels, and the studied populations were heterogeneous, as were the methodological approaches. The most consistent finding was an increase of Candida for both CD and UC and of Malassezia in CD, where it was often linked to a decrease of Saccharomyces. Conclusions The mycobiome is altered in IBD, as differences in beta diversity were found between cases and controls consistently. Future studies should carefully standardize every step from sample collection through analysis and data processing, allowing external validation of findings. Inclusion of treatment naïve patients and symptomatic controls could further advance this field.

• Mahdy, Aya K. H.; Schöpfel, Valentina; Huppertz-Hauss, Gert; Perminow, Gøri Margrete; Tran, Florian & Bang, Corinna [Show all 17 contributors for this article] (2025). Simultaneous profiling of the blood and gut T and B cell repertoires in Crohn’s disease and symptomatic controls illustrates tissue-specific alterations in the immune repertoire of individuals with Crohn’s disease. Frontiers in Immunology. 16. doi: 10.3389/fimmu.2025.1638522. Full text in Research Archive Show summary

  Introduction Crohn’s disease (CD) is a clinical subset of inflammatory bowel disease that is characterized by patchy transmural inflammation across the gastrointestinal tract. Although the exact etiology remains unknown, recent findings suggest that it is a complex multifactorial disease with contributions from the host genetics and environmental factors such as the microbiome. We have previously shown that the T cell repertoire of individuals with CD harbors a group of highly expanded T cells which hints toward an antigen-mediated pathology. Methods We simultaneously profiled the αβ and γδ T cell repertoire in addition to the B cell repertoire of both the blood and the colonic mucosa of 27 treatment-naïve individuals with CD and 27 age-matched symptomatic controls. Results Regardless of disease status, we observed multiple physiological differences between the immune repertoire of blood and colonic mucosa. Additionally, by comparing the repertoire of individuals with CD relative to controls, we observed different alterations that were only detected in the blood or colonic mucosa. These include a depletion of mucosal-associated invariant T (MAIT) cells and an expansion of TRAV29/DV5-TRAJ5 + clonotypes in the blood repertoire of individuals with CD. Also, a significant depletion of multiple IGHV3-33-IGHJ4 + and IGHV3-33-IGHJ6 + clonotypes in the blood and gut IGH repertoire of individuals with CD. Discussion Our findings highlight the importance of studying the immune repertoire in a tissue-specific manner and the need to profile the T and B cell immune repertoire of gut tissues as not all disease-induced alterations will be detected in the blood.

• Andersen, Svend; Bernklev, Tomm; Størdal, Ketil; Hagen, Milada; Kristensen, Vendel Ailin & Opheim, Randi [Show all 13 contributors for this article] (2025). Specific phenotypes may drive an increased incidence of pediatric inflammatory bowel disease in South‐Eastern Norway. Journal of Pediatric Gastroenterology and Nutrition - JPGN. ISSN 0277-2116. 81(5), p. 1227–1236. doi: 10.1002/jpn3.70148. Full text in Research Archive Show summary

  Abstract Objectives Pediatric inflammatory bowel disease (PIBD) incidence has increased in recent decades but may be stabilizing, prompting exploration of incidence changes, disease distribution, and severity. Methods From 2017 to 2019, patients under 18 years with PIBD symptoms were recruited from nine hospitals in South‐Eastern Norway for Inflammatory Bowel Disease in South‐Eastern Norway III (IBSEN III), a population‐based inception cohort study. The primary outcome was a diagnosis of any PIBD subtype as defined by revised Porto criteria. Paris classification system defined disease phenotypes, and descriptions of covariates were gathered from patients in IBSEN III. Results We identified 324 PIBD patients, with 216 consenting to the IBSEN III study. The crude incidence rate was 17.8 per 100,000 person‐years (PY) (95% confidence interval [CI]: 15.9–19.8). Crohn's disease (CD) was found in 118 patients (54.6%); 48% had ileocolonic distribution, 40% had upper gastrointestinal disease, and 12.8% had perianal disease. Complications (stricturing and/or penetrating) were noted in 18%. Ulcerative colitis (UC) was diagnosed in 78 patients (36.1%), predominantly pancolitis (41%), with 30% having proctitis. One in five suffered severe disease. IBD unclassified was found in 20 patients (9.3%). PIBD incidence in those under 16 was 13.6/100,000 PY, up from 4.7 in the IBSEN study 27 years ago. Terminal ileitis (11%–23%) and proctitis (14%–25%) rose from IBSEN (1990–1993) to IBSEN III, while stricturing/penetrating disease changed insignificantly (17%–16%). Conclusions The incidence of PIBD has risen in South‐Eastern Norway, with increased cases of terminal ileitis in CD, unchanged stricturing/penetrating disease, and increased proctitis in UC compared to the original IBSEN study. Trial registration ClinicalTrials.gov identifier: NCT02727959.

• Olsen, Bjørn Christian Elias Grova; Opheim, Randi; Kristensen, Vendel Ailin; Høivik, Marte Lie; Lund, Charlotte & Aabrekk, Tone Bergene [Show all 22 contributors for this article] (2025). Prevalence of Irritable Bowel Syndrome Based on Rome IV Criteria in Patients in Biochemical and Endoscopic Remission From Newly Diagnosed Inflammatory Bowel Disease: One- and Three-Year Results (the IBSEN III Cohort). Inflammatory Bowel Diseases. ISSN 1078-0998. 31(10), p. 2704–2713. doi: 10.1093/ibd/izaf047. Full text in Research Archive Show summary

  Background: Distinguishing irritable bowel syndrome (IBS) from inflammatory bowel disease (IBD) flare-ups is challenging. This study used objective remission markers to accurately determine IBS prevalence in a population-based cohort of patients with IBD. Methods: Adults with ulcerative colitis and Crohn’s disease were recruited from the IBD in South-Eastern Norway III cohort study. Irritable bowel-like symptoms were assessed using the Rome IV criteria for patients in remission from IBD at 1- and 3-year follow-ups. Remission was defined objectively using the biochemical marker fecal calprotectin (FC) ≤ 250 μg/g, and comparisons to remission based on endoscopic indices were made at 1-year follow-up. Results: Among patients with FC ≤ 250 μg/g, IBS prevalences were 21.9% (n = 62/283) and 16.1% (n = 49/304) at the 1- and 3-year follow-ups, respectively, which were higher than that in the Norwegian population (9.5%; P < .005). Of patients in endoscopic remission at 1-year follow-up, 19.2% (n = 43/224) reported IBS-like symptoms, which was not significantly different from IBS prevalence for patients with FC ≤ 250 μg/g. Irritable bowel syndrome was independently associated with substantial fatigue (odds ratio: 3.05 [95% CI, 1.48-6.27]) and female sex (odds ratio: 2.67 [95% CI, 1.34-5.32]) at the 1-year follow-up. Patients with IBS reported significantly reduced health-related quality of life (HRQoL) scores. Conclusions: The prevalence of IBS among patients in remission from IBD was approximately twice as common as that in the Norwegian population. Irritable bowel syndrome was independently associated with substantial fatigue, female sex, and reduced HRQoL.

• Zerouga, Insaf; Valeur, Jørgen; Sommer, Christine; Carlsen, Monica Hauger; Hagen, Milada & Høivik, Marte Lie [Show all 22 contributors for this article] (2025). Habitual Intake of Macronutrients and Fermentable Oligo-, Di-, Monosaccharides and Polyols is not associated with Irritable Bowel Syndrome-like Symptoms in Inflammatory Bowel Disease. Clinical Nutrition ESPEN. ISSN 2405-4577. 67, p. 105–113. doi: 10.1016/j.clnesp.2025.03.005. Full text in Research Archive
• Strande, Vibeke; Hagen, Milada; Lund, Charlotte; Asak, Øivind Wessel; Bengtson, May-Bente & Cetinkaya, Raziye Boyar [Show all 26 contributors for this article] (2025). Predicting severe inflammatory bowel disease: a risk matrix model based on the IBSEN III inception cohort. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 60(7), p. 716–727. doi: 10.1080/00365521.2025.2512591. Full text in Research Archive Show summary

  Background and aims: Identifying patients at risk of developing severe inflammatory bowel disease (IBD) can aid treatment decisions. However, predicting disease course remains challenging. We aimed to identify predictive factors associated with severe disease course in the first year after IBD diagnosis. Methods: Newly diagnosed adult (≥18 years) patients with IBD were recruited from a population-based inception cohort (IBSEN III study). Preselected baseline factors were tested for associations with severe disease course, defined as IBD-related hospitalisation, surgery, treatment with ≥2 steroid courses, >2 biologics and/or new event of complication (stricture, fistula, abscess only applicable Crohn's disease (CD)). From a best fitted multivariable logistic regression model stratified by diagnosis and age (18-40/>40 years), probability of severe disease for given combinations of predictive factors was summarised in prediction matrices. Results: At one-year follow-up, 90/559 (16%) patients with ulcerative colitis (UC) and 74/312 (24%) with CD had severe disease. Treatment with systemic steroids, vitamin D deficiency, Simple Clinical Colitis Activity Index >2, and hypoalbuminemia at diagnosis were all significantly associated with severe disease in UC patients. CD patients with stricturing or penetrating disease behaviour, systemic steroids and hypoalbuminemia at diagnosis were associated with severe disease course. The least favourable combination of these factors increased the probability of severe disease from 3% (95%CI[0-5%]) to 72% (95%CI[66-79%]) for UC and from 8% (95%CI[3-13%]) to 88% (95%CI[84-93%]) for CD. Conclusions: Our study identified predictive factors associated with severe disease the first year after diagnosis. The probability of severe disease summarised in matrices enables easy risk stratification.

• Pertsinidou, Eleftheria; Salomon, Benita; Bergemalm, Daniel; Salihovic, Samira; Hedin, Charlotte R.H. & Lundström, Maria [Show all 30 contributors for this article] (2025). Anti-integrin αvβ6 IgG antibody as a diagnostic and prognostic marker in ulcerative colitis: A cross-sectional and longitudinal study defining a specific disease phenotype. Journal of Crohn's and Colitis. ISSN 1873-9946. 19(5). doi: 10.1093/ecco-jcc/jjaf062. Full text in Research Archive
• Hoz-Martín, María P. de la; González-Fernández, Juan; Andreu-Ballester, Juan Carlos; Høivik, Marte Lie; Ricanek, Petr & Bruland, Torunn [Show all 9 contributors for this article] (2025). Prevalence of Anti-Anisakis simplex Antibodies in a Cohort of Patients with Inflammatory Bowel Disease in Norway. Pathogens. ISSN 2076-0817. 14(8). doi: 10.3390/pathogens14080769. Full text in Research Archive
• Hansen, Simen Hyll; Maseng, Maria Gjerstad; Grännö, Olle; Vestergaard, Marie V; Bang, Corinna & Olsen, Bjørn Christian Elias Grova [Show all 33 contributors for this article] (2025). Fecal Microbiome Reflects Disease State and Prognosis in Inflammatory Bowel Disease in an Adult Population-Based Inception Cohort. Inflammatory Bowel Diseases. ISSN 1078-0998. 31(8), p. 2066–2080. doi: 10.1093/ibd/izaf060. Full text in Research Archive
• Lundekvam, Jonas Andre; Høivik, Marte Lie; Anisdahl, Karoline; Hagen, Milada; Warren, David & Bolstad, Nils [Show all 7 contributors for this article] (2025). Tumour necrosis factor inhibitors in Ulcerative colitis: real-world data on Therapeutic drug monitoring and evaluation of current treatment targets (STRIDE II). Annals of Medicine. ISSN 0785-3890. 57(1). doi: 10.1080/07853890.2024.2424447. Full text in Research Archive Show summary

  Background The benefit of therapeutic drug monitoring (TDM) and implementation of recommendations from the Selection of Therapeutic Targets in Inflammatory Bowel Disease (IBD, STRIDE) are discussed in the IBD community. We report real-world data in ulcerative colitis patients receiving first-line tumour necrosis factor inhibitor (TNFi) treatment followed by TDM, and assess how implementation of the STRIDE II recommendations might affect clinical practice. Methods Adult, biologically naïve UC patients starting TNFi between 2014 and 2021 at Oslo University Hospital were included in a medical chart review study, and data were collected at three and twelve months after the start of treatment. Target serum drug levels were defined as ≥7.5 mg/L for adalimumab and ≥5 mg/L for infliximab. Results Of 141 included patients, 36% were in clinical and biochemical (combined) remission after twelve months. Among 102 treatment persistent patients, 54% were in combined remission after twelve months. Target drug level at three months was associated with clinical remission at twelve months (OR = 2.97, 95% CI [1.24–7.12]) and biochemical remission at twelve months (OR = 2.64, 95% CI [1.03–6.77]). In total, 56% of recorded dosage adjustments were related only to serum drug levels. Conclusions Combined remission rates at twelve months for treatment persistent patients suggest that 46% should have been considered for a change of treatment according to the STRIDE II recommendations. A majority of dosage adjustments were made proactively. Target drug level at three months was associated with remission at twelve months and supports the use of proactive TDM.

• Helm, Thea Elisabeth; Høivik, Marte Lie; Anisdahl, Karoline; Buer, Lydia Celine Tansem; Warren, David & Bolstad, Nils [Show all 9 contributors for this article] (2024). Subcutaneous Vedolizumab Treatment in a Real-World Inflammatory Bowel Disease Cohort Switched From Intravenous Vedolizumab: Eighteen-Month Prospective Follow-up Study. Crohn's & Colitis 360. 6(1). doi: 10.1093/crocol/otae013. Full text in Research Archive Show summary

  Background: Vedolizumab has since 2021 been available as a subcutaneous formulation. We aimed to assess 18-month drug persistence and possible predictive factors associated with discontinuation, safety, serum drug profile, drug dosing, and disease activity in a real-world cohort of patients with inflammatory bowel disease switched from intravenous to subcutaneous vedolizumab maintenance treatment. Methods: Eligible patients were switched to subcutaneous vedolizumab and followed for 18 months or until discontinuation of subcutaneous treatment. Data on preferred route of administration, adverse events, drug dosing, serum-vedolizumab, disease activity, fecal calprotectin, and C-reactive protein were collected. Persistence was described using Kaplan–Meier analysis. The impact of clinical and biochemical variables on persistence was analyzed with Cox proportional hazard models. Results: We included 108 patients, and the estimated 18-month drug persistence was 73.6% (95% CI [64.2–80.1]). Patients in clinical remission at switch were less likely to discontinue SC treatment (HR = 0.34, 95% CI [0.16–0.73], P = .006), and patients favoring intravenous treatment at switch were almost 3 times more likely to discontinue (HR = 2.78, 95% CI [1.31–5.90], P = .008). Four patients discontinued subcutaneous vedolizumab due to injection site reactions. At 18 months, 88% of patients administered subcutaneous vedolizumab with an interval of ≥ 14 days, and serum-vedolizumab was 39.1 mg/L. Disease activity was stable during follow-up. Conclusions: Three of the four patients remained on subcutaneous vedolizumab after 18 months, a large proportion received treatment at standard dosing intervals, and disease activity remained stable. This indicates that switching from intravenous to subcutaneous vedolizumab treatment is convenient and safe.

• Salihovic, Samira; Nyström, Niklas; Mathisen, Charlotte Bache-Wiig; Kruse, Robert; Olbjørn, Christine & Andersen, Svend [Show all 30 contributors for this article] (2024). Identification and validation of a blood- based diagnostic lipidomic signature of pediatric inflammatory bowel disease. Nature Communications. 15(1). doi: 10.1038/s41467-024-48763-7. Full text in Research Archive Show summary

  Improved biomarkers are needed for pediatric inflammatory bowel disease. Here we identify a diagnostic lipidomic signature for pediatric inflammatory bowel disease by analyzing blood samples from a discovery cohort of incident treatment-naïve pediatric patients and validating findings in an independent inception cohort. The lipidomic signature comprising of only lactosyl ceramide (d18:1/16:0) and phosphatidylcholine (18:0p/22:6) improves the diagnostic prediction compared with high-sensitivity C-reactive protein. Adding high-sensitivity C-reactive protein to the signature does not improve its performance. In patients providing a stool sample, the diagnostic performance of the lipidomic signature and fecal calprotectin, a marker of gastrointestinal inflammation, does not substantially differ. Upon investigation in a third pediatric cohort, the findings of increased lactosyl ceramide (d18:1/16:0) and decreased phosphatidylcholine (18:0p/22:6) absolute concentrations are confirmed. Translation of the lipidomic signature into a scalable diagnostic blood test for pediatric inflammatory bowel disease has the potential to support clinical decision making.

• Strande, Vibeke; Lund, Charlotte; Hagen, Milada; Bengtson, May-Bente; Cetinkaya, Raziye Boyar & Detlie, Trond Espen [Show all 23 contributors for this article] (2024). Clinical course of ulcerative colitis: Frequent use of biologics and low colectomy rate first year after diagnosis—results from the IBSEN III inception cohort. Alimentary Pharmacology and Therapeutics. ISSN 0269-2813. 60(3), p. 357–368. doi: 10.1111/apt.18097. Full text in Research Archive Show summary

  Background: The introduction of biologic therapies and the 'treat-to-target' treatment strategy may have changed the disease course of ulcerative colitis (UC). Aims: To describe the early disease course and disease outcome at 1-year follow-up in a population-based inception cohort of adult patients with newly diagnosed UC. Methods: The Inflammatory Bowel Disease in South-Eastern Norway (IBSEN) III study is a population-based inception cohort study with prospective follow-up. Patients newly diagnosed with inflammatory bowel disease during 2017-2019 were included. Patients ≥18 years at diagnosis of UC who attended the 1-year follow-up were investigated. We registered clinical, endoscopic and demographic data at diagnosis and 1-year follow-up. Results: We included 877 patients with UC (median age 36 years (range: 18-84), 45.8% female). At diagnosis, 39.2% presented with proctitis, 24.7% left-sided colitis and 36.0% extensive colitis. At the 1-year follow-up, 13.9% experienced disease progression, and 14.5% ha

• Lund, Charlotte; Strande, Vibeke; Hagen, Milada; Bengtson, May-Bente; Cetinkaya, Raziye Boyar & Detlie, Trond Espen [Show all 26 contributors for this article] (2024). Low Surgery Rates in Early Crohn's Disease: Results from a Prospective Population-Based Inception Cohort—The Inflammatory Bowel Disease in South-Eastern Norway III Study. Inflammatory Bowel Diseases. ISSN 1078-0998. doi: 10.1093/ibd/izae297. Full text in Research Archive Show summary

  Background and aims: The emergence of biologic therapy has coincided with a decline in surgery rates for Crohn's disease (CD). This study aims to describe the disease course, including intra-abdominal surgery rates, biologic therapy use, and variables associated with biologic therapy initiation in a cohort of newly diagnosed CD patients. Methods: The Inflammatory Bowel Disease in South-Eastern Norway (IBSEN) III study is a population-based inception cohort study. From 2017 to 2019, newly diagnosed inflammatory bowel disease patients were included for prospective follow-up. The present study included CD patients ≥ 18 years. Clinical, endoscopic, and demographic data were collected at diagnosis and 1-year follow-up. Data were analyzed by using the Kaplan-Meier method and regression analyses. Results: In total, 424 CD patients (median age 37.0 years (range 18-80), female 55.0%) were included. At diagnosis, 50.5% presented with ileal disease and 80.7% with inflammatory behavior. Within a 1-year follow-up, 39.6%

• Oliver, Amanda J.; Huang, Ni; Casado, Raquel Bartolome; Li, Ruoyan; Koplev, Simon & Nilsen, Hogne Røed [Show all 54 contributors for this article] (2024). Single-cell integration reveals metaplasia in inflammatory gut diseases. Nature. ISSN 0028-0836. 635(8039), p. 699–707. doi: 10.1038/s41586-024-07571-1. Full text in Research Archive Show summary

  The gastrointestinal tract is a multi-organ system crucial for efficient nutrient uptake and barrier immunity. Advances in genomics and a surge in gastrointestinal diseases1,2 has fuelled efforts to catalogue cells constituting gastrointestinal tissues in health and disease3. Here we present systematic integration of 25 single-cell RNA sequencing datasets spanning the entire healthy gastrointestinal tract in development and in adulthood. We uniformly processed 385 samples from 189 healthy controls using a newly developed automated quality control approach (scAutoQC), leading to a healthy reference atlas with approximately 1.1 million cells and 136 fine-grained cell states. We anchor 12 gastrointestinal disease datasets spanning gastrointestinal cancers, coeliac disease, ulcerative colitis and Crohn’s disease to this reference. Utilizing this 1.6 million cell resource (gutcellatlas.org), we discover epithelial cell metaplasia originating from stem cells in intestinal inflammatory diseases with transcriptional similarity to cells found in pyloric and Brunner’s glands. Although previously linked to mucosal healing4, we now implicate pyloric gland metaplastic cells in inflammation through recruitment of immune cells including T cells and neutrophils. Overall, we describe inflammation-induced changes in stem cells that alter mucosal tissue architecture and promote further inflammation, a concept applicable to other tissues and diseases.

• Dale, Hanna Fjeldheim; Hagen, Milada; Malmstrøm, Gunn Helen; Fiennes, Jennifer Twisleton; Høivik, Marte Lie & Kristensen, Vendel Ailin [Show all 7 contributors for this article] (2024). Assessing hard and loose “endpoints”: comparison of patient and expert Bristol Stool Scale scoring of 2280 fecal samples. F1000 Research. 13. doi: 10.12688/f1000research.152496.2. Full text in Research Archive Show summary

  Background Stool consistency is an important outcome measure to evaluate in the investigation of several gastrointestinal diseases. The Bristol Stool Scale (BSS) is one of the most commonly used tools for evaluation of stool consistency. BSS ranges from 1-7 and each score is assigned to a given consistency of the feces. Self-reported characterizations can differ from an expert evaluation, and the reliability of BSS is unclear. We aimed to evaluate the reliability of BSS by comparing patient scores with expert scores. Methods Patients with inflammatory bowel disease collected stool samples throughout a 3-year follow-up. The stool´s consistency was evaluated with BSS by the patients and matched with an expert score. Agreement between patient and expert scores was assessed using Cohen’s kappa. Results BSS scores from 2280 fecal samples collected from 992 patients at up to five time points were included. When all samples were compared, there was good to substantial agreement between patient and expert scores (Cohen’s weighted kappa: 0.66-0.72). When the BSS scores were simplified and categorized as 1 (scores 1-2), 2 (scores 3-5) or 3 (scores 6-7), the agreement improved slightly (Cohen’s weighted kappa: 0.73-0.77). When the scores from the first sample per patient were compared, the experts were more likely to assign higher scores compared to the patient. The proportion of the lowest assigned scores (1-2) was 12.1% for patients and 8.1% for experts. Conclusions The agreement between patient and expert BSS scores is good to substantial, especially when the BSS scores are simplified into three categories.

• Andersen, Vibeke; Pingel, Jessica; Søfelt, Heidi Lynge; Hikmat, Zainab; Johansson, Mads & Pedersen, Vera Slyk [Show all 26 contributors for this article] (2024). Sex and gender in inflammatory bowel disease outcomes and research. The Lancet Gastroenterology and Hepatology. ISSN 2468-1253. 9(11), p. 1041–1051. doi: 10.1016/S2468-1253(24)00159-6. Full text in Research Archive
• Holten, Kristina Ingeborg; Bernklev, Tomm; Opheim, Randi; Olsen, Bjørn Christian Elias Grova; Detlie, Trond Espen & Strande, Vibeke [Show all 18 contributors for this article] (2024). Fatigue in Patients with Inflammatory Bowel Disease in Remission One Year after Diagnosis (the IBSEN III Study). Journal of Crohn's and Colitis. ISSN 1873-9946. 19(4). doi: 10.1093/ecco-jcc/jjae170. Full text in Research Archive Show summary

  Background and aims: Fatigue is commonly observed in Crohn's disease (CD) and ulcerative colitis (UC), but its association to achieving remission is not clearly established. In this study we describe the odds for fatigue in patients with CD/UC one year after diagnosis based on different definitions of remission and identified factors associated with chronic fatigue (CF) among patients in endoscopic/radiological remission. Methods: Patients ≥18 years with CD/UC were recruited from the IBSEN III cohort. Using the Fatigue Questionnaire, and dichotomizing the score, CF was defined as the presence of substantial fatigue (SF) for ≥6 months. Remission was divided into symptomatic (CD: HBI score<5/UC: SCCAI score<3), biochemical (faecal calprotectin ≤250µg/g), endoscopic/radiological (CD: normal intestinal MRI/CT combined with normal endoscopy/UC: Mayo endoscopic score 0) and histological (normal mucosal biopsies). Both the likelihood of SF/CF, depending on the definition of remission, and associations between CF an

• Zerouga, Insaf; Valeur, Jørgen; Sommer, Christine; Småstuen, Milada Cvancarova; Medhus, Asle Wilhelm & Lund, Charlotte [Show all 22 contributors for this article] (2024). Dietary intake and nutritional status in patients with newly diagnosed inflammatory bowel disease: insights from the IBSEN III study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 59(6), p. 1–9. doi: 10.1080/00365521.2024.2313056. Full text in Research Archive Show summary

  Background: Dietary recommendations in inflammatory bowel disease (IBD) are inconclusive, and patients may follow restrictive diets with increased risk of malnutrition. The aim of this study was to compare dietary intakes and nutritional status in men and women with newly diagnosed IBD with a general population sample, and to investigate whether intakes were in line with the Nordic Nutrition Recommendations. Methods: This was a cross-sectional study including adults≥ 40 years with IBD from the Inflammatory Bowel Disease in South-Eastern Norway (IBSEN) III cohort study. A validated food frequency questionnaire (FFQ) was used in dietary data collection, and a sample from the seventh survey of the Tromsø Study was included as a comparison group. Results: A total of 227 men and women with IBD were included. IBD patients had higher intake of grain products, sweetened beverages, energy, fat and polyunsaturated fat (PUFA), but lower intake of dairy products, alcohol and iodine compared to adults from the comparison sample (p < 0.01). Intakes of saturated fat and carbohydrates in both genders, and vitamin D in women were not within recommended levels. Anemia and hypoalbuminemia were more prevalent in IBD patients than in the comparison sample. Conclusions: Dietary intakes in newly diagnosed IBD patients were mostly in line with Nordic Nutrition Recommendations. Higher proportion of IBD patients exceeded recommended allowances of fat and added sugar than the comparison sample. Insufficient micronutrient intake, anemia and hypoalbuminemia are present challenges in IBD patients that require monitoring.

• Anisdahl, Karoline; Lirhus, Sandre Svatun; Medhus, Asle Wilhelm; Moum, Bjørn Allan; Melberg, Hans Olav & Høivik, Marte Lie (2024). Frailty risk and treatment strategy in elderly-onset inflammatory bowel disease. A Norwegian nationwide population-based registry study. Digestive and Liver Disease. ISSN 1590-8658. doi: 10.1016/j.dld.2024.02.002. Full text in Research Archive Show summary

  Background/Aims: To determine real-world medical and surgical treatment patterns in elderly-onset inflammatory bowel disease in a nationwide cohort, and to investigate associations between frailty and treatment choices.<p> <p>Methods: Norwegian health registries were used to identify adult-onset (born 1950–1989) and elderlyonset (born 1910–1949) patients with Crohn’s disease (CD) and ulcerative colitis (UC) diagnosed 2010– 2017 (n = 13,006). Patients were classified as no, low and intermediate/high frailty risk after the Hospital Frailty Risk Score. Outcomes included use of medical and surgical treatment. <p>Results: Within five years, elderly-onset patients received less biologics (13% [CD], 7% [UC]) and immunomodulators (24% [CD], 11% [UC]), and major surgery was more frequent (22% [CD], 9% [UC]) than in adult-onset. Respective log rank tests were significant (p < 0.01). Compared to no frailty risk groups, elderly-onset UC with intermediate/high frailty risk had lower probability of starting biologics (4% versus 9%), immunomodulators (7% versus 13%) and 5-aminosalisylic acids (66% versus 84%), and elderly-onset CD with intermediate/high frailty risk had higher probability of starting prednisolone (67% versus 49%). Respective log rank tests were significant (p < 0.05). <p>Conclusions: Elderly-onset patients received less biologics and immunomodulators and a larger proportion underwent major surgery. Frailty risk in elderly-onset patients was associated with increased use of prednisolone, and less use of 5-aminosalisylic acids, immunomodulators and biologics.

• Braadland, Peder Rustøen; Bergquist, Annika; Kummen, Martin; Bossen, Lars; Engesæter, Lise Katrine & Reims, Henrik Mikael [Show all 21 contributors for this article] (2023). Clinical and biochemical impact of vitamin B6 deficiency in primary sclerosing cholangitis before and after liver transplantation. Journal of Hepatology. ISSN 0168-8278. 79(4), p. 955–966. doi: 10.1016/j.jhep.2023.05.038. Full text in Research Archive Show summary

  Background and aims We previously demonstrated that people with primary sclerosing cholangitis (PSC) had reduced gut microbial capacity to produce active vitamin B6 (pyridoxal 5’-phosphate [PLP]), which corresponded to lower circulating PLP levels and poor outcomes. Here, we define the extent and biochemical and clinical impact of vitamin B6 deficiency in people with PSC from several centers before and after liver transplantation (LT). Methods We used targeted liquid chromatography-tandem mass spectrometry to measure B6 vitamers and B6-related metabolic changes in blood from geographically distinct cross-sectional cohorts totaling 373 people with PSC and 100 healthy controls to expand on our earlier findings. Furthermore, we included a longitudinal PSC cohort (n = 158) sampled prior to and serially after LT, and cohorts of people with inflammatory bowel disease (IBD) without PSC (n = 51) or with primary biliary cholangitis (PBC) (n = 100), as disease controls. We used Cox regression to measure the added value of PLP to predict outcomes before and after LT. Results In different cohorts, 17-38% of people with PSC had PLP levels below the biochemical definition of a vitamin B6 deficiency. The deficiency was more pronounced in PSC than in IBD without PSC and PBC. Reduced PLP was associated with dysregulation of PLP-dependent pathways. The low B6 status largely persisted after LT. Low PLP independently predicted reduced LT-free survival in both non-transplanted people with PSC and in transplant recipients with recurrent disease. Conclusions Low vitamin B6 status with associated metabolic dysregulation is a persistent feature of PSC. PLP was a strong prognostic biomarker for LT-free survival both in PSC and recurrent disease. Our findings suggest that vitamin B6 deficiency modifies the disease and provides a rationale for assessing B6 status and testing supplementation. Impact and implications We previously found that people with PSC had reduced gut microbial potential to produce essential nutrients. Across several cohorts, we find that the majority of people with PSC are either vitamin B6 deficient or have a marginal deficiency, which remains prevalent even after liver transplantation. Low vitamin B6 levels strongly associate with reduced liver transplantation-free survival as well as deficits in biochemical pathways dependent on vitamin B6, suggesting that the deficiency has a clinical impact on the disease. The results provide a rationale for measuring vitamin B6 and to investigate whether vitamin B6 supplementation or modification of the gut microbial community can help improve outcomes for people with PSC.

• Johansen, Ingunn; Småstuen, Milada Cvancarova; Løkkeberg, Stine Eileen Torp; Kristensen, Vendel Ailin; Høivik, Marte Lie & Lund, Charlotte [Show all 16 contributors for this article] (2023). Symptoms and symptom clusters in patients newly diagnosed with inflammatory bowel disease: results from the IBSEN III Study. BMC Gastroenterology. 23(1). doi: 10.1186/s12876-023-02889-y. Full text in Research Archive Show summary

  Patients with inflammatory bowel disease report multiple symptoms, but the relationships among co-occurring symptoms are poorly understood. This study aimed to examine the prevalence of symptoms and explore symptom clusters and possible associations between symptom clusters and socio-demographic and clinical variables in patients newly diagnosed with inflammatory bowel disease. Methods The IBSEN III study is a prospective population-based inception cohort of patients with inflammatory bowel disease. This study used patient data from the three largest hospitals in the study catchment area. The Memorial Symptom Assessment Scale was used to assess the prevalence of symptoms. Symptom clusters were identified using principal component analysis. Possible associations between socio-demographic and clinical variables and symptom cluster membership were estimated using regression analysis. Results Of the 573 patients (age, ≥18 years) diagnosed with inflammatory bowel disease, 350 (61.1%) completed the questionnaire (responders). Eleven symptoms were reported by >50% of the responders. The three most prevalent symptoms were bloating (84%), drowsiness (81%), and lack of energy (81%). Three symptom clusters were identified: psychological (56% of the patients), impaired energy (28%), and physical (16%) clusters. Multinomial regression analysis revealed that vitamin D deficiency was significantly associated with the impaired energy cluster (odds ratio=2.49, 95% confidence interval [1.00-6.2], p=0.05). Conclusions We found high symptom prevalence in patients newly diagnosed with inflammatory bowel disease. Three distinct symptom clusters were identified, and the psychological cluster includes >50% of the patients. Vitamin D deficiency is the only factor associated with cluster membership, namely the impaired energy cluster.

• Fossmark, Reidar; Lirhus, Sandre Svatun & Høivik, Marte Lie (2023). The impact of proton pump inhibitors on the course of ulcerative colitis: a cohort study of over 10,000 newly diagnosed patients in Norway. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. doi: 10.1080/00365521.2023.2255710. Full text in Research Archive Show summary

  Background and Aims Proton pump inhibitors (PPI) affect the gastrointestinal microbiota, which is thought to play a role in the pathogenesis of ulcerative colitis (UC). Previous studies suggest an association between PPI use and risk of incident UC as well as disease course. The aim of the study was to examine if PPI exposure is associated with disease course in UC patients. Methods A national cohort consisting of all newly diagnosed UC patients from 2010 to 2020 was defined combining data from Norwegian registries. PPI exposure was included as a time dependent variable with a 30 day time lag from starting the drug. Outcomes were starting advanced therapies including anti-TNF, systemic glucocorticoids, any additional systemic anti-inflammatory medication and undergoing colectomy during follow-up. Time-dependent Cox regressions included the variables PPI use, first systemic glucocorticoid prescription, first UC hospitalization, age-groups and sex. Results The study cohort consisted of 10,149 patients with median age 40 years (IQR 27–56) and 56% males. PPI use independently increased the risk of starting advanced therapies (HR 1.54, 95% CI 1.36–1.73, p < 0.005), starting systemic glucocorticoids (HR 1.20, 95% CI 1.07–1.34, p < 0.005), starting any additional anti-inflammatory treatment (HR 1.18, 95%CI 1.05–1.32, p < 0.01) and undergoing colectomy (HR 1.52, 95%CI 1.17–1.98, p < 0.005). Conclusions PPI use was associated with unfavorable outcomes including advanced therapy initiation, additional anti-inflammatory medications and undergoing colectomy. Although further studies are needed, the evidence suggests that PPIs could affect the course of UC and should be used cautiously in UC patients.

• Holten, Kristina Ingeborg; Bernklev, Tomm; Opheim, Randi; Johansen, Ingunn; Olsen, Bjørn Christian Elias Grova & Lund, Charlotte [Show all 22 contributors for this article] (2023). Fatigue in Patients with Newly Diagnosed Inflammatory Bowel Disease: Results from a Prospective Inception Cohort, the IBSEN III Study. Journal of Crohn's and Colitis. ISSN 1873-9946. 17(11), p. 1781–1790. doi: 10.1093/ecco-jcc/jjad094. Full text in Research Archive Show summary

  Background and aims: Although fatigue is common in inflammatory bowel disease (IBD), its pathogenesis remains unclear. This study aimed to determine the prevalence of fatigue and its associated factors in a cohort of patients newly diagnosed with IBD. Methods: Patients ≥18 years were recruited from the Inflammatory Bowel Disease South-Eastern Norway (IBSEN III) study, a population-based, observational inception cohort. Fatigue was assessed using the Fatigue Questionnaire and compared with data from a Norwegian general population. Univariate and multivariate linear and logistic regression analyses were performed to evaluate the associations of total fatigue (TF) (continuous score) and substantial fatigue (SF) (dichotomized score ≥4) with sociodemographic, clinical, endoscopic, laboratory, and other relevant patient data. Results: In total, 983/1509 (65.1%) patients with complete fatigue data were included (ulcerative colitis (UC), 68.2%; Crohn's disease (CD), 31.8%). The prevalence of SF was higher in CD (69.6%) compared with UC (60.2%) (p<0.01), and in both diagnoses when compared to the general population (p<0.001).In the multivariate analyses, depressive symptoms, pain intensity, and sleep disturbances were associated with increased TF for both diagnoses. In addition, increased clinical disease activity and Mayo endoscopic score were significantly associated with TF in UC, whereas all disease-related variables were insignificant in CD. Similar findings were observed for SF, except regarding the Mayo endoscopic score. Conclusions: SF affects approximately two-thirds of patients newly diagnosed with IBD. Fatigue was associated with depressive symptoms, sleep disturbances, and increased pain intensity in both diagnoses, while clinical and endoscopic activity were associated factors only in UC.

• Olsen, Bjørn Christian Elias Grova; Opheim, Randi; Høivik, Marte Lie; Lund, Charlotte; Aabrekk, Tone Bergene & Johansen, Ingunn [Show all 15 contributors for this article] (2023). Health-related quality of life in patients with newly diagnosed inflammatory bowel disease: an observational prospective cohort study (IBSEN III). Quality of Life Research. ISSN 0962-9343. 32(10), p. 2951–2964. doi: 10.1007/s11136-023-03435-9. Full text in Research Archive Show summary

  Purpose This unselected, population-based cohort study aimed to determine the level of health-related quality of life (HRQoL) in patients with Crohn’s disease (CD) and ulcerative colitis (UC) at the time of diagnosis compared with a reference population and identify the demographic factors, psychosocial measures, and disease activity markers associated with HRQoL. Methods Adult patients newly diagnosed with CD or UC were prospectively enrolled. HRQoL was measured using the Short Form 36 (SF-36) and Norwegian Inflammatory Bowel Disease Questionnaires. Clinical significance was assessed using Cohen’s d effect size and further compared with a Norwegian reference population. Associations between HRQoL and symptom scores, demographic factors, psychosocial measures, and disease activity markers were analyzed. Results Compared with the Norwegian reference population, patients with CD and UC reported significantly lower scores in all SF-36 dimensions, except for physical functioning. Cohen’s d effect sizes for men and women in all SF-36 dimensions were at least moderate, except for bodily pain and emotional role for men with UC and physical functioning for both sexes and diagnoses. In the multivariate regression analysis, depression subscale scores ≥ 8 on the Hospital Anxiety and Depression Scale, substantial fatigue, and high symptom scores were associated with reduced HRQoL. Conclusion Patients newly diagnosed with CD and UC reported statistically and clinically significantly lower scores in seven of the eight SF-36 dimensions than the reference population. Symptoms of depression, fatigue, and elevated symptom scores were associated with poorer HRQoL.

• Helm, Thea Elisabeth; Høivik, Marte Lie; Buer, Lydia Celine Tansem; Warren, David; Bolstad, Nils & Moum, Bjørn Allan [Show all 9 contributors for this article] (2023). Switching from intravenous to subcutaneous vedolizumab maintenance treatment in patients with inflammatory bowel disease followed by therapeutic drug monitoring. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 58(8), p. 863–873. doi: 10.1080/00365521.2023.2176252. Full text in Research Archive Show summary

  Objective: Vedolizumab (VDZ) for subcutaneous (SC) administration has recently become available. We aimed to assess feasibility, safety and clinical outcome when switching from intravenous (IV) to SC VDZ maintenance treatment in a real world cohort of patients with inflammatory bowel disease (IBD) followed by therapeutic drug monitoring (TDM). Methods: Eligible IBD patients were switched from IV to SC treatment and assessed six months prior to switch, at baseline and six, twelve and twenty-six weeks after switch. Primary outcome was propor- tion of patients on SC treatment after 26 weeks. Secondary outcomes included adverse events (AEs), clinical disease activity, biochemical markers, treatment interval, serum-VDZ (s-VDZ), preferred route of administration and health-related quality of life. Results: In total, 108 patients were switched. After 26 weeks, 100 patients (92.6%) were still on SC treatment and median s-VDZ was 47.6 mg/L (IQR 41.3 54.6). The most frequent AE was injection site reaction (ISR), reported by 20 patients (18.5%). There were no clinically significant changes in disease activity, biochemical markers and quality of life. The proportion of patients preferring SC administra- tion increased from 28.0% before switch to 59.4% after 26 weeks (p < 0.001). Conclusions: Nine out of ten patients still received SC treatment after 26 weeks. No change in disease activity occurred, and levels of serum VDZ increased. Although almost one fifth of patients experi- enced ISRs, a higher proportion favored SC administration at 26 weeks. This study demonstrates that SC maintenance treatment is a safe and feasible alternative to IV treatment.

• Jørgensen, Kristin Kaasen; Høivik, Marte Lie; Chopra, Adity; Benth, Jurate Saltyte; Ricanek, Petr & Moum, Bjørn Allan [Show all 18 contributors for this article] (2023). Humoral immune response to SARS-CoV-2 vaccination in patients with inflammatory bowel disease on immunosuppressive medication: association to serum drug levels and disease type. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 58(8), p. 874–882. doi: 10.1080/00365521.2023.2177884. Full text in Research Archive Show summary

  Objectives Immune responses following SARS-CoV-2 vaccination in patients with inflammatory bowel disease (IBD) are not well characterized. The aims of this study were to explore the serological response associated with IBD, and immunosuppressive medications including serum concentrations of biologics and thiopurine metabolites. Materials and methods This prospective, observational study included adult patients with ulcerative colitis (UC) and Crohn’s disease (CD), and healthy controls. Antibodies to the receptor-binding domain of SARS-CoV-2 spike proteins, and serum concentrations of ongoing biologic and immunomodulatory medications were assessed prior to, and 2-5 weeks after the second vaccine dose. Serologic response was defined as anti-Spike antibodies ≥70 AU/ml. Results In 958 IBD patients (380 UC, 578 CD) and 323 healthy controls, the median (Q1; Q3) anti-Spike antibody level (AU/ml) was lower in patients (618 (192; 4370)) compared to controls (3355 (896; 7849)) (p < 0.001). The antibody levels were lower in CD (439 (174; 3304)) compared to UC (1088 (251; 5975)) (p < 0.001). No associations were demonstrated between antibody levels and serum drug concentrations for TNF inhibitor (TNFi), vedolizumab and ustekinumab. Patients receiving TNFi + thiopurines with a subtherapeutic 6-thioguanine nucleotide (6-TGN) level had higher response rate (93%) compared to patients with 6-TGN within the therapeutic range (53%) (p = 0.003). A diagnosis of UC, mRNA-1273 vaccine, and other treatments than TNFi + thiopurines were associated with humoral response. Conclusions Patients with CD had an attenuated humoral response to SARS-COV-2 vaccination as compared to patients with UC. The lack of association between serum levels of biologics and serologic response indicates vaccination regardless of proximity to drug administration.

• Burisch, Johan; Zhao, Mirabella; Odes, Selwyn; Cruz, Peter De; Vermeire, Severine & Bernstein, Charles N [Show all 33 contributors for this article] (2023). The cost of inflammatory bowel disease in high-income settings: a Lancet Gastroenterology & Hepatology Commission. The Lancet Gastroenterology and Hepatology. ISSN 2468-1253. 8(5), p. 458–492. doi: 10.1016/S2468-1253(23)00003-1. Full text in Research Archive Show summary

  The cost of caring for patients with inflammatory bowel disease (IBD) continues to increase worldwide. The cause is not only a steady increase in the prevalence of Crohn's disease and ulcerative colitis in both developed and newly industrialised countries, but also the chronic nature of the diseases, the need for long-term, often expensive treatments, the use of more intensive disease monitoring strategies, and the effect of the diseases on economic productivity. This Commission draws together a wide range of expertise to discuss the current costs of IBD care, the drivers of increasing costs, and how to deliver affordable care for IBD in the future. The key conclusions are that (1) increases in health-care costs must be evaluated against improved disease management and reductions in indirect costs, and (2) that overarching systems for data interoperability, registries, and big data approaches must be established for continuous assessment of effectiveness, costs, and the cost-effectiveness of care. International collaborations should be sought out to evaluate novel models of care (eg, value-based health care, including integrated health care, and participatory health-care models), as well as to improve the education and training of clinicians, patients, and policy makers.

• Tran, Trung; Vaage, Eline Benno; Mehta, Adi; Chopra, Adity; Tietze, Lisa & Kolderup, Heidi Anette [Show all 40 contributors for this article] (2022). Titers of antibodies against ancestral SARS-CoV-2 correlate with levels of neutralizing antibodies to multiple variants. npj Vaccines. 7(1). doi: 10.1038/s41541-022-00586-7. Full text in Research Archive Show summary

  Diagnostic assays currently used to monitor the efficacy of COVID-19 vaccines measure levels of antibodies to the receptor-binding domain of ancestral SARS-CoV-2 (RBDwt). However, the predictive value for protection against new variants of concern (VOCs) has not been firmly established. Here, we used bead-based arrays and flow cytometry to measure binding of antibodies to spike proteins and receptor-binding domains (RBDs) from VOCs in 12,000 serum samples. Effects of sera on RBD-ACE2 interactions were measured as a proxy for neutralizing antibodies. The samples were obtained from healthy individuals or patients on immunosuppressive therapy who had received two to four doses of COVID-19 vaccines and from COVID-19 convalescents. The results show that anti-RBDwt titers correlate with the levels of binding- and neutralizing antibodies against the Alpha, Beta, Gamma, Delta, Epsilon and Omicron variants. The benefit of multiplexed analysis lies in the ability to measure a wide range of anti-RBD titers using a single dilution of serum for each assay. The reactivity patterns also yield an internal reference for neutralizing activity and binding antibody units per milliliter (BAU/ml). Results obtained with sera from vaccinated healthy individuals and patients confirmed and extended results from previous studies on time-dependent waning of antibody levels and effects of immunosuppressive agents. We conclude that anti-RBDwt titers correlate with levels of neutralizing antibodies against VOCs and propose that our method may be implemented to enhance the precision and throughput of immunomonitoring.

• Zhao, Mirabella; Lirhus, Sandre Svatun; Lördal, Mikael; Langholz, Ebbe; Knudsen, Torben & Voutilainen, Markku [Show all 15 contributors for this article] (2022). Therapeutic management and outcomes in inflammatory bowel diseases, 2010 to 2017 in cohorts from Denmark, Sweden and Norway. Alimentary Pharmacology and Therapeutics. ISSN 0269-2813. 56(6), p. 989–1006. doi: 10.1111/apt.17145. Full text in Research Archive
• Anisdahl, Karoline; Lirhus, Sandre Svatun; Medhus, Asle Wilhelm; Moum, Bjørn; Melberg, Hans Olav & Høivik, Marte Lie (2021). First-line biologic treatment of inflammatory bowel disease during the first 12 months after diagnosis from 2010 to 2016: a Norwegian nationwide registry study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. p. 1–7. doi: 10.1080/00365521.2021.1955147. Full text in Research Archive Show summary

  Objectives The use of biologic therapy in inflammatory bowel disease (IBD) is likely to increase with lower costs and more biologics and biosimilars becoming available. Our aim was to estimate the trends in use of first-line biologics during the first year after diagnosis in a Norwegian IBD population from 2010 to 2016. Methods Data were collected from the Norwegian National Patient Registry and Norwegian Prescription Database. Patients defined as incident IBD cases between 2010 and 2016 were included and followed for 12 months. Patients were stratified by year of diagnosis to examine change over time. Chi-square test was used for calculations on proportions. Time from diagnosis to first biologic was calculated by Kaplan-Meier failure estimates. Results 14,645 patients were included, 5283 (36%) with Crohn’s disease (CD) and 9362 (64%) with ulcerative colitis (UC). In the 2010 and 2016 cohort, the proportion initiating biologics increased from 17% to 33% (p < .001) for CD and 7% to 13% (p < .001) for UC. The most frequently used first-line biologics were infliximab (CD: 64% and UC: 82%) and adalimumab (CD: 36% and UC: 15%). The highest registered use of adalimumab was in the 2012 cohort (CD: 56% and UC: 39%). In the 2014–2016 cohorts, infliximab was the most used first-line biologic for both CD and UC. Conclusions The proportion of IBD patients initiating biologics within 12 months after diagnosis increased between 2010 and 2016. The use of infliximab as first-line biologic increased after the approval of biosimilar infliximab in 2013.

• Sousa, Paula; Ministro, Paula; Armuzzi, Alessandro; Dignass, Axel; Høivik, Marte Lie & Acosta, Manuel Barreiro-de [Show all 11 contributors for this article] (2021). Thiopurines: Use them or lose them? International survey on current and future use of thiopurines in inflammatory bowel disease. Digestive and Liver Disease. ISSN 1590-8658. 53(12), p. 1571–1579. doi: 10.1016/j.dld.2021.05.038. Full text in Research Archive
• Lirhus, Sandre Svatun; Høivik, Marte Lie; Moum, Bjørn; Anisdahl, Karoline & Melberg, Hans Olav (2021). Incidence and prevalence of inflammatory bowel disease in norway and the impact of different case definitions: A nationwide registry study. Clinical Epidemiology. 13, p. 287–294. doi: 10.2147/CLEP.S303797. Full text in Research Archive Show summary

  Background: Countries have different diagnostic procedures and treatment regimens for inflammatory bowel disease (IBD) patients. In addition to differences in population characteristics, completeness of data and health registries, different follow-up time and case definitions can have a large impact on estimates of the incidence and prevalence of IBD. Aim: The aim of this study was to use hospital and prescription data to estimate incidence and prevalence of Crohn’s disease (CD) and ulcerative colitis (UC), using different case definitions. Methods: This study used nationwide data from the Norwegian Patient Registry (2008 to 2017) and the Norwegian Prescription Database (2004 to April 2018). Incidence and prevalence were estimated using different case definitions of an IBD patient, varying the number of IBD-related hospital visits and IBD prescriptions required. The base case definition included patients with at least one IBD hospital visit and two IBD prescriptions or two IBD hospital visits. Results: From 2010 to 2017, 16,758 incident IBD patients fulfilled our base case definition, with 6045 diagnosed with CD (36.1%) and 10,713 (63.9%) with UC. For CD, 47.2% of the patients were male while 53.8% of UC patients were male. The base case incidence varied between 14.1 and 16.0 per 100,000 person-years for CD and 24.7 and 28.4/100,000 person-years for UC patients in the years 2010– 2017. When we required at least two IBD hospital visits, not utilizing the prescription data, the CD incidence was 22.3 per 100,000 person-years in 2010 and 13.9 per 100,000 person-years in 2017. For UC, the incidence was 47.4 and 20.6 per 100,000 person-years in 2010 and 2017. In 2017, the prevalence of CD was 0.27% (95% CI: 0.26– 0.27) and 0.50% (95% CI: 0.490– 0.502) for UC. Conclusion: According to our base case definition, the incidence of IBD in Norway was stable from 2010 to 2017. Both the incidence and prevalence of IBD in Norway is among the highest in the world. Moreover, the study also highlights the consequences of different case definitions.

• Kristensen, Vendel Ailin; Opheim, Randi; Perminow, Gøri Margrete; Huppertz-Hauss, Gert; Detlie, Trond Espen & Lund, Charlotte [Show all 39 contributors for this article] (2021). Inflammatory bowel disease in South-Eastern Norway III (IBSEN III): a new population-based inception cohort study from South-Eastern Norway. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 56(8), p. 899–905. doi: 10.1080/00365521.2021.1922746. Full text in Research Archive Show summary

  Background and aim: Modern treatment strategies for inflammatory bowel disease (IBD) are postulated to change the natural disease course. Inception cohort studies are the gold standard for investigating such changes. We have initiated a new population-based inception cohort study; Inflammatory bowel disease in South Eastern Norway III (IBSEN III). In this article, we describe the study protocol and baseline characteristics of the cohort. Methods: IBSEN III is an ongoing, population-based observational inception cohort study with prospective follow-up. Adult and pediatric patients with suspected IBD in the South-Eastern Health Region of Norway (catchment area of 2.95 million inhabitants in 2017), during the 3-year period from 2017 to 2019, were eligible for inclusion. Comprehensive clinical, biochemical, endoscopic, demographic, and patient-reported data were collected at the time of diagnosis and throughout standardized follow-up. For a portion of the patients, extensive biological material was biobanked. Results: The study included 2168 patients, of whom 1779 were diagnosed with IBD (Crohn's disease: 626, ulcerative colitis: 1082, IBD unclassified: 71). In 124 patients, there were subtle findings indicative of, but not diagnostic for, IBD. The remaining 265 patients were classified as symptomatic non-IBD controls. Conclusion: We have included patients in a comprehensive population-based IBD cohort from a catchment population of 2.95 million, and a unique biobank with materials from newly diagnosed and treatment-naïve IBD patients and symptomatic non-IBD controls. We believe this cohort will add important knowledge about IBD in the years to come.

• Kristensen, Vendel Ailin; Småstuen, Milada Cvancarova; Høivik, Marte Lie; Moum, Bjørn & Vatn, Morten H (2020). Serological antibodies and surgery in a population-based inception cohort of Crohn's disease patients - the IBSEN study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. doi: 10.1080/00365521.2020.1745879. Full text in Research Archive Show summary

  Introduction: Serological antibodies have been associated with complicated disease course in Crohn’s disease (CD), including the need for surgery. Aim: The aim of this study was to investigate if a panel of relevant antibodies could predict surgery in a prospective population-based cohort of patients with CD. Methods: The population-based IBSEN cohort has been followed prospectively for 20years. At the 10and 20-year follow-up, the following panel of serological antibodies was analysed: pANCA, ASCA IgA, ASCA IgG, anti-OmpC, anti-I2, and anti-CBir1. At the 20-year follow-up or until lost to follow-up, all CDrelated surgeries were registered. Results: Serum was available from 159 patients at 10-year follow-up and 135 patients at 20-year follow-up. In 113 patients, serum was available at both time points. No significant change of antibody status (positive vs. negative) was found from 10-year to 20-year follow-up. Negative pANCA, positive ASCA IgA and positive ASCA IgG at 10-year follow-up were all individually associated with increased risk for CD-related surgery. There was no association between anti-OmpC, anti-I2 or anti-CBir1 and CDrelated surgery. In a multiple regression model including disease location and behaviour, only stricturing or penetrating disease behaviour and negative pANCA remained significantly associated with higher odds for surgery. Conclusion: Positive ASCA IgA and IgG, and negative pANCA were associated with higher odds for CD-related surgery in univariate analysis. Since disease phenotype changes during the disease course, while serological antibodies are stable, our results support the use of pANCA, ASCA IgA and ASCA IgG as prognostic markers in CD.

• Kummen, Martin; Thingholm, Louise B.; Rühlemann, Malte C.; Holm, Kristian; Hansen, Simen Hyll & Moitinho-Silva, Lucas [Show all 22 contributors for this article] (2020). Altered Gut Microbial Metabolism of Essential Nutrients in Primary Sclerosing Cholangitis. Gastroenterology. ISSN 0016-5085. 160(5). doi: 10.1053/j.gastro.2020.12.058. Full text in Research Archive Show summary

  Background & Aims To influence host and disease phenotype, compositional microbiome changes, which have been demonstrated in patients with primary sclerosing cholangitis (PSC), must be accompanied by functional changes. We therefore aimed to characterize the genetic potential of the gut microbiome in patients with PSC compared with healthy controls (HCs) and patients with inflammatory bowel disease (IBD). Methods Fecal DNA from 2 cohorts (1 Norwegian and 1 German), in total comprising 136 patients with PSC (58% with IBD), 158 HCs, and 93 patients with IBD without PSC, were subjected to metagenomic shotgun sequencing, generating 17 billion paired-end sequences, which were processed using HUMAnN2 and MetaPhlAn2, and analyzed using generalized linear models and random effects meta-analyses. Results Patients with PSC had fewer microbial genes compared with HCs (P < .0001). Compared with HCs, patients with PSC showed enrichment and increased prevalence of Clostridium species and a depletion of, for example, Eubacterium spp and Ruminococcus obeum. Patients with PSC showed marked differences in the abundance of genes related to vitamin B6 synthesis and branched-chain amino acid synthesis (Qfdr < .05). Targeted metabolomics of plasma from an independent set of patients with PSC and controls found reduced concentrations of vitamin B6 and branched-chain amino acids in PSC (P < .0001), which strongly associated with reduced liver transplantation–free survival (log-rank P < .001). No taxonomic or functional differences were detected between patients with PSC with and without IBD. Conclusions The gut microbiome in patients with PSC exhibits large functional differences compared with that in HCs, including microbial metabolism of essential nutrients. Alterations in related circulating metabolites associated with disease course, suggesting that microbial functions may be relevant for the disease process in PSC.

• Klepp, Pasquale Catherine; Brackmann, Stephan; Småstuen, Milada Cvancarova; Høivik, Marte Lie; Hovde, Øistein & Henriksen, Magne [Show all 15 contributors for this article] (2020). Risk of colorectal cancer in a population-based study 20 years after diagnosis of ulcerative colitis: results from the IBSEN study. BMJ open gastroenterology. 7. doi: 10.1136/bmjgast-2019-000361. Full text in Research Archive Show summary

  Objective The association between ulcerative colitis (UC) and colorectal cancer (CRC) is widely accepted, although attenuated risk has been reported in recent years. Colonoscopic surveillance is recommended with intervals based on established clinical risk factors. Nevertheless, a significant number of patients develop interval cancers, indicating the need of improved individualised assessment. In the present study, we evaluated clinical risk factors associated with CRC during a prescheduled follow-up 20 years after diagnosis, the IBSEN study. Design A population-based inception cohort of patients diagnosed with inflammatory bowel disease from 1 January 1990 until 31 December 1993, prospectively followed at 1, 5, 10 and 20 years after diagnosis. A total of 517 patients with UC were included; 264 (51 %) men; median age at inclusion 37.4 years (4–88). Results The overall incidence of CRC was 1.6% (8/517) at a 20-year follow-up. The total lifetime risk of CRC prior to or after UC diagnosis was 2.3%. (12/517). Patients older than 70 years at diagnosis had a 15-fold higher risk of CRC compared with those diagnosed when younger than 40 years, with HR 15.68 (95% CI: 1.31 to 187.92). Neither sex, first-degree relative with CRC, extent of colitis nor primary sclerosing cholangitis affected the risk of CRC. Conclusion The risk of CRC in UC was low and comparable with the risk of CRC in the background population of Norway.

• Kravdal, Øystein; Magnus, Per; Moum, Bjørn & Høivik, Marte Lie (2020). Childbearing is Associated with a Short-term Reduced Risk of Crohn’s Disease in Mothers. American Journal of Epidemiology. ISSN 0002-9262. 189(4), p. 294–304. doi: 10.1093/aje/kwz285. Full text in Research Archive Show summary

  Our aim in this study was to analyze the importance of childbearing for risk of inflammatory bowel disease. Using data from the Norwegian Population Register and the Norwegian Patient Register, we fitted discrete-time hazard models for diagnosis of Crohn disease (CD) or ulcerative colitis (UC) among men and women aged 18–81 years in 2011–2016. Year and various sociodemographic factors were controlled for. The data included 4,304 CD cases and 8,866 UC cases. Women whose youngest child was ≤4 years of age had lower CD risk the following year than childless women (odds ratio (OR) = 0.73, 95% confidence interval (CI): 0.62, 0.86). There was no such reduction in CD risk among fathers. Men whose youngest child was aged ≥20 years had higher risks of CD (OR = 1.22, 95% CI: 1.01, 1.49) and UC (OR = 1.15, 95% CI: 1.02, 1.30) than childless men. UC risk was also increased among men whose youngest child was aged ≤4 years (OR = 1.14, 95% CI: 1.02, 1.27). The short-term reduction in women’s CD risk after a birth may reflect biological effects of pregnancy. Alternatively, it may reflect residual confounding or lifestyle effects of parenthood that are of special relevance for CD in women. In particular, differences in use of oral contraceptives (which it was not possible to control for) may have contributed to the observed pattern.

• Frigstad, Svein Oskar; Høivik, Marte Lie; Jahnsen, Jørgen; Småstuen, Milada C; Grimstad, Tore & Berset, Ingrid Prytz [Show all 11 contributors for this article] (2020). Pain Severity and Vitamin D Deficiency in IBD Patients. Nutrients. 12(1), p. 1–12. doi: 10.3390/nu12010026. Full text in Research Archive Show summary

  Background: Pain and vitamin D deficiency are common in inflammatory bowel disease (IBD). Disease activity, fatigue, frequent relapses, prior surgery and psychological factors all seem to influence the experience of pain in IBD. Vitamin D deficiency has been associated with muscle and skeletal pain. This study aimed to determine whether there is an association between vitamin D deficiency and severity of pain in patients with IBD, and to investigate the influence of other socio-demographic and psychological variables on the experience of pain. Methods: Patients with IBD were recruited from nine hospitals in Norway in a multicenter cross-sectional study. The Brief Pain Inventory (BPI) questionnaire was used to measure pain. Disease activity was assessed using clinical disease activity indices, C-reactive protein (CRP) and fecal calprotectin. Regression models were fitted to explore a possible association between 25-hydroxyvitamin D and pain severity. Results: Of 407 patients included in the analyses, 229 (56%) had Crohn's disease (CD) and 178 (44%) had ulcerative colitis (UC). Vitamin D deficiency was present in half (203/407) of patients. Presence of pain was reported by 76% (309/407). More severe pain was associated with female gender and increased disease activity scores, but not with increased CRP or fecal calprotectin. In CD, patients without prior intra-abdominal surgery reported more severe pain. In multivariate analyses, there was no association between 25-hydroxyvitamin D and pain severity. Conclusions: In this study, no significant association between pain severity and vitamin D deficiency was revealed in patients with IBD. Keywords: pain severity; patient reported outcomes; vitamin D deficiency.

• Kravdal, Øystein; Magnus, Per; Moum, Bjørn & Høivik, Marte Lie (2020). Association of Childbearing with a Short-Term Reduced Risk of Crohn Disease in Mothers. American Journal of Epidemiology. ISSN 0002-9262. 189(4), p. 294–304. doi: 10.1093/aje/kwz285. Full text in Research Archive
• Ossum, Alvilde Maria; Palm, Øyvind; Småstuen, Milada C; Bernklev, Tomm; Jahnsen, Jørgen & Moum, Bjørn [Show all 7 contributors for this article] (2020). The Impact of Spondyloarthritis and Joint Symptoms on Health-Related Quality of Life and Fatigue in IBD Patients. Results from a Population-Based Inception Cohort (20-Year Follow-up in the Ibsen Study). Inflammatory Bowel Diseases. ISSN 1078-0998. doi: 10.1093/ibd/izz105. Full text in Research Archive Show summary

  Background: Patients with inflammatory bowel disease (IBD) often suffer from musculoskeletal manifestations. Health-related quality of life (HRQoL) and fatigue are known to be associated with IBD activity and musculoskeletal complaints. The aim of this study was to determine the association between spondyloarthritis, arthralgia, or back pain and the patient-reported outcomes of HRQoL and fatigue in IBD patients 20 years after their diagnosis. Methods: The IBSEN cohort was followed prospectively for 20 years. At the 20-year follow-up, the patients answered detailed questionnaires regarding rheumatological manifestations, intestinal symptoms, HRQoL, and fatigue. Multiple regression analyses were used to evaluate associations between spondyloarthritis or joint symptoms and HRQoL or fatigue. Sex, IBD diagnosis, and age were included in all the multiple regression models, in addition to other clinically relevant confounders. Results: In total, 441 patients (94%) completed the questionnaires at the 20-year follow-up. The criteria for spondyloarthritis (axial or peripheral) were fulfilled in 158 patients (36%), current back pain during the previous 3 months was reported by 79 patients (18%), and current arthralgia was reported by 178 patients (40%). Current back pain and arthralgia were independently associated with lower HRQoL, higher levels of fatigue, and chronic fatigue. A diagnosis of spondyloarthritis was not associated with reduced HRQoL or fatigue when adjusted for possible confounders. Conclusions: Current joint symptoms in IBD patients 20 years after diagnosis were associated with poorer HRQoL, higher levels of fatigue, and chronic fatigue, whereas spondyloarthritis did not impact HRQoL or fatigue negatively in this cohort.

• Buer, Lydia Celine Tansem; Moum, Bjørn; Småstuen, Milada Cvancarova; Warren, David; Bolstad, Nils & Medhus, Asle Wilhelm [Show all 7 contributors for this article] (2018). Real world data on effectiveness, safety and therapeutic drug monitoring of vedolizumab in patients with inflammatory bowel disease. A single center cohort. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. p. 1–9. doi: 10.1080/00365521.2018.1548646. Full text in Research Archive
• Ossum, Alvilde Maria; Palm, Øyvind; Småstuen, Milada Cvancarova; Solberg, Inger Camilla; Vatn, Morten H & Moum, Bjørn [Show all 7 contributors for this article] (2018). Peripheral arthritis in patients with long-term inflammatory bowel disease. Results from 20 years of follow-up in the IBSEN study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. p. 1–8. doi: 10.1080/00365521.2018.1518482. Full text in Research Archive Show summary

  Objectives: Peripheral arthritis and related musculoskeletal manifestations, often classified as peripheral spondyloarthritis, are frequently seen in patients with inflammatory bowel disease (IBD). Few long-term studies have reported on the prevalence of these conditions. The aim of this study was to determine the prevalence of IBD-related peripheral arthritis and peripheral spondyloarthritis in IBD patients during 20 years of disease course, and to assess whether these conditions were associated with the intestinal IBD severity and activity. Materials and methods: In an inception cohort (the IBSEN study), IBD patients were followed prospectively for 20 years. At the 5 year follow-up the patients underwent a rheumatological examination and at the 20 year follow-up they completed a questionnaire with identical questions. When peripheral arthritis was characteristic and not explained by other specific diagnoses, it was defined as IBDrelated peripheral arthritis. The Assessment of Spondyloarthritis International Society criteria were used to define peripheral spondyloarthritis, including patients with peripheral arthritis, enthesitis and/ or dactylitis. Results: After 20 years of follow-up, 441 patients were included (296 ulcerative colitis and 145 Crohn’s disease). The prevalence of IBD-related peripheral arthritis was 17.2% and peripheral spondyloarthritis 27.9% during the disease course. IBD severity and activity were not different between those with a history of IBD-related peripheral arthritis or peripheral spondyloarthritis and those without. A higher proportion of women had IBD-related peripheral arthritis and peripheral spondyloarthritis. Conclusion: During 20 years of disease course, more than every sixth patient had suffered from IBDrelated peripheral arthritis and every fourth from peripheral spondyloarthritis.

• Lirhus, Sandre Svatun; Høivik, Marte Lie; Moum, Bjørn & Melberg, Hans Olav (2018). Regional differences in anti-TNF-a therapy and surgery in the treatment of inflammatory bowel disease patients: a Norwegian nationwide cohort study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 53(8), p. 952–957. doi: 10.1080/00365521.2018.1495258. Full text in Research Archive Show summary

  Background and aims: During the last decades, substantial progress has been made in both medical and surgical treatment of inflammatory bowel disease (IBD). The aim of this study was to determine the use of anti-TNFs and surgery during the first 3 years after diagnosis in IBD patients across the four health regions in Norway using nationwide patient registry data. Methods: This study used nationwide data from the Norwegian Patient Registry. Cumulative incidence of anti-TNF exposure and major surgery was calculated for patients diagnosed in 2010–2012. The analyses were stratified by diagnosis and health region. All patients were followed for an equal period of 3 years from diagnosis. Results: The study population included 8,257 IBD patients first registered between 2010 and 2012, of whom 2,829 were diagnosed with Crohn’s disease (CD) and 5,428 with ulcerative colitis (UC). Across Norway’s health regions, the cumulative incidence of major surgery after 3 years varied from 11.4% to 17.1% for CD and from 4.6% to 6.9% for UC. The cumulative incidence of anti-TNF exposure varied from 20.9% to 31.4% for CD and from 8.0% to 13.5% for UC. The region with the lowest anti-TNF use had the highest surgery rates for both UC and CD. Conclusions: Cumulative incidence of anti-TNF exposure and surgery varied significantly across Norway’s health regions during the three first years after IBD diagnosis.

• Frigstad, Svein Oskar; Høivik, Marte Lie; Jahnsen, Jørgen; Småstuen, Milada Cvancarova; Grimstad, Tore & Berset, Ingrid Prytz [Show all 11 contributors for this article] (2018). Fatigue is not associated with vitamin D deficiency in inflammatory bowel disease patients. World Journal of Gastroenterology (WJG). ISSN 1007-9327. 24(29), p. 3293–3301. doi: 10.3748/wjg.v24.i29.3293. Full text in Research Archive Show summary

  AIM To investigate if vitamin D deficiency is associated with fatigue in patients with inflammatory bowel disease (IBD). METHODS IBD patients were recruited from nine hospitals in the southeastern and western regions of Norway to participate in a multicenter cross-sectional study lasting from March 2013 to April 2014. Data were collected by interviews, from medical records and laboratory tests. The Fatigue Questionnaire (FQ) was used to measure fatigue. Linear and logistic regression models were applied to explore the possible association between vitamin D deficiency and total fatigue scores and chronic fatigue, respectively. The analyses were adjusted for age, gender, disease activity, depressive symptoms and sleep disturbance. RESULTS In total, 405 patients were included in the analyses, of which 227 (56%) had Crohn’s disease (CD) and 178 (44%) had ulcerative colitis (UC). Vitamin D deficiency (< 50 nmol/L) was present in half (203/405) of the patients. Chronic fatigue was reported by 116 (29%) of all included patients with substantial fatigue reported by 194 (48%). Vitamin D levels were neither associated with total fatigue nor with chronic fatigue. Higher total fatigue scores and chronic fatigue were both associated with increased disease activity scores in patients with UC and CD, but not with increased CRP or fecal calprotectin. In UC patients, female gender was associated with fatigue in the univariate analysis, but no such difference was found when adjusted for elevated disease activity scores. Sleep disturbance and more depressive symptoms were associated with total fatigue scores in both UC and CD patients, but with chronic fatigue only in CD patients. CONCLUSION In this study, no significant association between fatigue and vitamin D deficiency in IBD patients was revealed. Key Words: Inflammatory bowel disease, Crohn’s disease, Ulcerative colitis, Fatigue, Chronic fatigue, Vitamin D deficiency Core tip: Fatigue is common in inflammatory bowel diseases (IBD) and is especially prevalent in active disease. We wanted to investigate if vitamin D deficiency was associated to fatigue in IBD as this is a common belief among both patients and physicians. To the best of our knowledge, no previous studies have investigated this possible association in IBD patients. We also wanted to take into account the multidimensional approach in understanding fatigue making it difficult to single out any one contributing factor. In this study, no significant association between fatigue and vitamin D deficiency in IBD patients was revealed.

• Ossum, Alvilde Maria; Palm, Øyvind; Kapica, Aida; Småstuen, Milada C; BANITALEBI, HASAN & Negård, Anne [Show all 10 contributors for this article] (2018). Ankylosing Spondylitis and Axial Spondyloarthritis in Patients With Long-term Inflammatory Bowel Disease: Results From 20 Years of Follow-up in the IBSEN Study. Journal of Crohn's and Colitis. ISSN 1873-9946. 12(1), p. 96–104. doi: 10.1093/ecco-jcc/jjx126. Full text in Research Archive Show summary

  Background Patients with inflammatory bowel disease [IBD] often suffer from rheumatic manifestations, including inflammatory back disorders. The prevalence of these disorders late in the course of IBD is poorly investigated. The aim of this study was to estimate the prevalence of inflammatory back disorders in patients with IBD 20 years after diagnosis, and to investigate possible associations with IBD severity, HLA-B27, and the NOD2 genotype. Methods A population-based cohort [the IBSEN study] was followed prospectively for 20 years. Information covering IBD activity and rheumatic diseases was collected at the regular follow-ups. HLA-B27 and NOD2 were analysed as present or absent. Results At 20 years, 599 members of the original cohort were alive, of whom 470 [78.5%] were investigated [314 ulcerative colitis and 156 Crohn’s disease patients]. Ankylosing spondylitis was diagnosed in 21 patients [4.5%], axial spondyloarthritis was diagnosed in 36 patients [7.7%], and inflammatory back pain was diagnosed in 54 patients [11.5%]. Chronic back pain [back pain > 3 months] was present in 220 patients [46.8%]. HLA-B27 was associated with ankylosing spondylitis, axial spondyloarthritis, and inflammatory back pain, whereas no significant association was found for NOD2. A more chronic IBD course was associated with axial spondyloarthritis. Conclusions Our data revealed a high prevalence of ankylosing spondylitis, axial spondyloarthritis, and inflammatory back pain 20 years after the IBD diagnosis. HLA-B27 but not NOD-2 was a predisposing factor for the inflammatory back disorders in IBD patients. Axial spondyloarthritis was associated with a more chronic active IBD disease course.

• Høivik, Marte Lie; Buer, Lydia Celine Tansem; Småstuen, Milada Cvancarova; Warren, David; Bolstad, Nils & Moum, Bjørn [Show all 7 contributors for this article] (2018). Switching from originator to biosimilar infliximab?real world data of a prospective 18 months follow-up of a single-centre IBD population. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 53(6), p. 692–699. doi: 10.1080/00365521.2018.1463391. Full text in Research Archive
• Buer, Lydia Celine Tansem; Høivik, Marte Lie; Warren, David; Medhus, Asle Wilhelm & Moum, Bjørn (2018). Combining Anti-TNF-? and Vedolizumab in the Treatment of Inflammatory Bowel Disease: A Case Series. Inflammatory Bowel Diseases. ISSN 1078-0998. 24(5), p. 997–1004. doi: 10.1093/ibd/izx110. Full text in Research Archive Show summary

  Background Anti-tumor necrosis factor α (anti-TNF-α) is important in the treatment of inflammatory bowel disease, but some patients experience only a partial response. In these patients, a combination of anti-TNF-α and vedolizumab (VDZ) may act as a bridge until the full VDZ effect occurs. At present, clinical data on combination treatment with anti-TNF-α and VDZ are not available. The aim of this case series was to evaluate the safety and clinical response of combination therapy with anti-TNF-α and VDZ in clinical practice. Methods All patients started on combination treatment with anti-TNF-α and VDZ from November 2015 to July 2016 were prospectively followed for at least 12 months. Results Six patients with ulcerative colitis and four patients with Crohn’s disease received combination treatment. These patients were followed for a median of 1712–20 months. No more adverse events than expected with anti-TNF-α alone were observed during combination treatment. At the end of follow-up, all patients were in clinical remission, and 8 patients could discontinue anti-TNF-α treatment and receive VDZ monotherapy. Two of the patients with Crohn’s disease required combination treatment throughout follow-up to obtain sustained remission. Conclusion Our findings suggest that combination treatment with anti TNF-α and VDZ is safe and might represent a long-term treatment option in selected patients.

• Henriksen, Magne; Høivik, Marte Lie; Jelsness-Jørgensen, Lars-Petter & Moum, Bjørn (2018). Irritable bowel-like symptoms in ulcerative colitis are as common in patients in deep remission as with inflammation; results from a population-based study (the IBSEN study). Journal of Crohn's and Colitis. ISSN 1873-9946. 12(4), p. 389–393. doi: 10.1093/ECCO-JCC/JJX152. Full text in Research Archive
• Frigstad, Svein Oskar; Høivik, Marte; Jahnsen, Jørgen; Dahl, Sandra Rinne; Småstuen, Milada C & Grimstad, Tore [Show all 13 contributors for this article] (2017). Vitamin D deficiency in inflammatory bowel disease: Prevalence and predictors in a Norwegian outpatient population. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 52(1), p. 100–106. doi: 10.1080/00365521.2016.1233577. Full text in Research Archive Show summary

  Background and aim: Vitamin D deficiency is common in inflammatory bowel disease (IBD). The aims of the present study were to determine the prevalence of vitamin D deficiency and to identify clinical and epidemiological variables associated with vitamin D deficiency in an outpatient population with IBD. Methods: Participants were recruited from nine hospitals in the southeastern and western regions of Norway as part of an observational, multicentre study from March 2013 to April 2014. Clinical and epidemiological data were collected by interview and from medical records. All analyses of serum 25-hydroxyvitamin D (25-OH-D) were performed in the same laboratory. Results: In total, 49% (200/408) of the patients had a 25-OH-D concentration <50 nmol/L, including 53% (122/230) of the Crohn’s disease (CD) patients and 44% (78/178) of the ulcerative colitis (UC) patients. In CD patients, disease activity, measured as the HBI, was inversely associated with vitamin D deficiency. No such association was observed with the Simple Clinical Colitis Activity Index (SCCAI) scores in UC, but in UC patients, vitamin D deficiency was associated with elevated faecal calprotectin >100 mg/kg. In patients with CD, there were significantly more relapses during the previous year in patients with vitamin D deficiency. Conclusions: Vitamin D deficiency was common, especially in CD, and was associated with increased disease activity, a relapsing disease course and higher inflammatory activity.

• Tronstad, Rune Rose; Kummen, Martin; Holm, Kristian; Volkmann, Hilde Løland Von; Anmarkrud, Jarl Andreas & Høivik, Marte Lie [Show all 13 contributors for this article] (2017). Guanylate cyclase C activation shapes the intestinal microbiota in patients with familial diarrhea and increased susceptibility for Crohn's disease. Inflammatory Bowel Diseases. ISSN 1078-0998. 23(10), p. 1752–1761. doi: 10.1097/MIB.0000000000001264. Full text in Research Archive
• Buer, Lydia Celine Tansem; Høivik, Marte Lie; Medhus, Asle Wilhelm & Moum, Bjørn (2017). Does the Introduction of Biosimilars Change Our Understanding about Treatment Modalities for Inflammatory Bowel Disease? Digestive Diseases. ISSN 0257-2753. 35(1-2), p. 74–82. doi: 10.1159/000449087. Full text in Research Archive
• Huppertz-Hauss, Gert; Høivik, Marte; Jelsness-Jørgensen, Lars-Petter; Opheim, Randi; Henriksen, Magne & Høie, Ole Ingebreth [Show all 13 contributors for this article] (2017). Fatigue in a population-based cohort of patients with inflammatory bowel disease 20 years after diagnosis: The IBSEN study. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 52(3), p. 351–358. doi: 10.1080/00365521.2016.1256425. Full text in Research Archive
• Jørgensen, Silje Fjellgård; Trøseid, Marius; Kummen, Martin; Anmarkrud, Jarl Andreas; Michelsen, Annika & Osnes, Liv T. N. [Show all 21 contributors for this article] (2016). Altered gut microbiota profile in common variable immunodeficiency associates with levels of lipopolysaccharide and markers of systemic immune activation. Mucosal Immunology. ISSN 1933-0219. doi: 10.1038/mi.2016.18. Full text in Research Archive
• Jelsness-Jørgensen, Lars-Petter; Bernklev, Tomm; Hovde, Øistein; Berset, Ingrid Prytz; Huppertz-Hauss, Gert & Moum, Bjørn [Show all 7 contributors for this article] (2016). Patients’ perceptions of quality of care and follow-up in inflammatory bowel disease. Scandinavian Journal of Gastroenterology. ISSN 0036-5521. 51(4), p. 434–441. doi: 10.3109/00365521.2015.1102319. Full text in Research Archive
• Kapica, Aida; Hov, Johannes Espolin Roksund; Borthne, Arne Sigmund; Gleditsch, Jostein; Johannesen, Glenn & Tveit, Knut [Show all 19 contributors for this article] (2016). Prevalence of Sclerosing Cholangitis Detected by Magnetic Resonance Cholangiography in Patients With Long-term Inflammatory Bowel Disease. Gastroenterology. ISSN 0016-5085. 151(4), p. 660–669. doi: 10.1053/j.gastro.2016.06.021. Full text in Research Archive
• Opheim, Randi; Høivik, Marte; Bernklev, Tomm; Jelsness-Jørgensen, Lars-Petter & Moum, Bjørn (2016). The use of complementary and alternative medicine (CAM) among patients with inflammatory bowel disease (IBD) is associated with reduced health-related quality of life (HRQoL). Gastroenterology Research and Practice. ISSN 1687-6121. 2016. doi: 10.1155/2016/6453657. Full text in Research Archive
• Wanderås, Magnus; Moum, Bjørn; Høivik, Marte Lie & Hovde, Øistein (2016). Predictive factors for a severe clinical course in ulcerative colitis: Results from population-based studies. World Journal of Gastrointestinal Pharmacology and Therapeutics (WJGPT). 7(2), p. 235–241. doi: 10.4292/WJGPT.v7.i2.235. Full text in Research Archive

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• Maseng, Maria Gjerstad; Hansen, S Hyll; Bang, Corina; Valeur, Jørgen; Huppertz-Hauss, Gert & Opheim, Randi [Show all 18 contributors for this article] (2025). Longitudinal Changes in Gut Microbiota During the First Year following diagnosis of Inflammatory Bowel Disease – the IBSEN III study. Journal of Crohn's and Colitis. ISSN 1873-9946. 19, p. i2387–i2387. doi: 10.1093/ecco-jcc/jjae190.1498. Full text in Research Archive
• Maseng, Maria Gjerstad; Hansen, Simen Hyll; Bang, Corina; Valeur, Jørgen; Huppertz-Hauss, Gert & Opheim, Randi [Show all 18 contributors for this article] (2025). Longitudinal Changes in Gut Microbiota During the First Year following diagnosis of Inflammatory Bowel Disease – the IBSEN III study. Full text in Research Archive
• Bakke, Ingunn & Høivik, Marte Lie (2025). Camilla (35) fant løsningen på inflammatorisk tarmsykdom (IBD): –⁠ Jeg var redd for å gå ut. [Journal]. VG+. doi: https:/www.vg.no/forbruker/i/gw2E8a/camilla-35-fant-loesningen-paa-inflammatorisk-tarmsykdom-ibd-jeg-var-redd-for-aa-gaa-ut. Full text in Research Archive
• Strande, Vibeke; Høivik, Marte Lie & Kristensen, Vendel Ailin (2024). Letter: Critical appraisal of biologic therapy in early ulcerative colitis management—Addressing study limitations and the role of psychological resilience—Authors' reply. Alimentary Pharmacology and Therapeutics. ISSN 0269-2813. doi: 10.1111/apt.18187. Full text in Research Archive
• Fejrskov, Anja; Füchtbauer, Johannes David; Davíðsdóttir, Lóa G; Halfvarson, Jonas; Høivik, Marte Lie & Jensen, Michael Dam [Show all 15 contributors for this article] (2024). Novel biomarker profiles to improve individual diagnosis and prognosis in patients with suspected inflammatory bowel disease: protocol for the Nordic inception cohort study (NORDTREAT). BMJ Open. 14(5). doi: 10.1136/bmjopen-2023-083144. Full text in Research Archive Show summary

  Introduction Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn’s disease, can be challenging to diagnose, and treatment outcomes are difficult to predict. In the NORDTREAT cohort study, a Nordic prospective multicentre study, we aim to identify novel molecular biomarkers of diagnostic value by assessing the diagnostic test accuracy (cross-sectionally), as well as the prognostic utility when used as prognostic markers in the long-term (cohort study). In the diagnostic test accuracy study, the primary outcome is a successful diagnosis using one or more novel index tests at baseline compared with the ECCO criteria as the reference standard. The composite outcome of the prognostic utility study is ‘severe IBD’ within 52 weeks from inclusion, defined as one or more of the following three events: IBD-related surgery, IBD-related hospitalisation or IBD-related death. Methods and analysis We aim to recruit 800 patients referred on suspicion of IBD to this longitudinal observational study, a collaboration between 11 inclusion sites in Denmark, Iceland, Norway and Sweden. Inclusion will occur from February 2022 until December 2023 with screening and baseline visits for all participants and three outcome visits at weeks 12, 26 and 52 after baseline for IBD-diagnosed patients. Biological material (blood, faeces, biopsies, urine and hair), clinical data and lifestyle information will be collected during these scheduled visits. Ethics and dissemination This study will explore novel biomarkers to improve diagnostic accuracy and prediction of disease progression, thereby improving medical therapy and the quality of life for patients with IBD.

• Rejler, Martin; Füchtbauer, Johannes David; Davíðsdóttir, Lóa G; Fejrskov, Anja; Söderholm, Johan D. & Christensen, Robin [Show all 11 contributors for this article] (2024). Nordic inflammatory bowel disease treatment strategy trial: protocol for the NORDTREAT randomised controlled biomarker-strategy trial. BMJ Open. 14(7). doi: 10.1136/bmjopen-2023-083163. Full text in Research Archive Show summary

  Introduction The absence of reliable prognostic markers poses a challenge to the management of inflammatory bowel disease (IBD). Patients with aggressive disease may not receive sufficient treatment with conventional ‘step-up’ therapy, whereas a top-down approach may expose patients with indolent disease to unnecessary treatment-related toxicity. The objective of the Nordic IBD treatment strategy trial (NORDTREAT) is to assess the feasibility of personalised therapy by stratifying patients according to a prognostic serum protein signature at diagnosis. Methods and analysis NORDTREAT is a multicentre, biomarker-strategy design, open-label controlled trial. After screening consent, eligible patients are randomised (1:1) into one of two groups: a group with access to the protein signature and a group without access. In the access to protein signature group, patients displaying a protein signature suggestive of an increased risk of an aggressive disease course will be treated in line with a top-down treatment algorithm (anti-tumour necrosis factor agent with/without an immunomodulator). In contrast, those with a protein signature indicative of indolent disease will be excluded from the trial. Patients not in the access group receive treatment based on clinical management. This traditional management involves a stepwise escalation of treatment as determined by the investigator after failure of first-line treatment. After 52 weeks, outcomes are assessed in the subgroup of patients with a protein profile indicating a potentially severe disease trajectory. The primary endpoint is a composite of the proportion of patients with corticosteroid-free clinical and endoscopic remission at week 52. Surgical intervention due to IBD during follow-up will be defined as treatment failure. Ethics and dissemination Ethical approval has been obtained, and recruitment is underway at sites in four participating Nordic countries (Denmark, Iceland, Norway and Sweden). Following trial completion and data analysis, the trial results will be submitted for publication in peer-reviewed journals and presented at international conferences. Trial registration number NCT05180175; Pre-results. EudraCT number: 2019-002942-19.

• Maseng, Maria Gjerstad; Hansen, Simen Hyll; Bang, Corina; Detlie, Trond Espen; Huppertz-Hauss, Gert & Kristensen, Vendel Ailin [Show all 18 contributors for this article] (2024). Longitudinal Changes in Gut Microbiota During the First Year following diagnosis of Inflammatory Bowel Disease– the IBSEN III study. Full text in Research Archive
• Johansen, Ingunn; Hagen, Milada; Løkkeberg, Stine Eileen Torp; Kristensen, Vendel; Høivik, Marte Lie & Lund, Charlotte [Show all 24 contributors for this article] (2024). P247 Anxiety and depression in newly diagnosed patients with Inflammatory Bowel Disease – Results from the IBSEN III study. Full text in Research Archive
• Bazov, I.; Kruse, R.; Bergemalm, D.; Eriksson, C.; Hedin, C.R. & Nieuwenhoven, M. van [Show all 28 contributors for this article] (2023). A novel serum protein signature as biomarker for Inflammatory Bowel Disease: A diagnostic performance and prediction modelling study using data from two independent inception cohorts. Journal of Crohn's and Colitis. ISSN 1873-9946. 17, p. i314–i315. doi: 10.1093/ecco-jcc/jjac190.0284. Full text in Research Archive
• Mathisen, Carl Magnus Bache Wiig; Nyström, N.; Bazov, I.; Andersen, S.; Olbjørn, Christine & Perminow, Gøri Margrete [Show all 22 contributors for this article] (2023). A novel diagnostic serum protein signature for paediatric Inflammatory Bowel Disease: A discovery and validation study in two independent inception cohorts. Journal of Crohn's and Colitis. ISSN 1873-9946. 17, p. i71–i71. doi: 10.1093/ecco-jcc/jjac190.0051. Full text in Research Archive
• Hansen, Simen Hyll; Maseng, M Gjerstad; Bjørkqvist, O; Halfvarsson, J; Bang, C & Detlie, Trond Espen [Show all 23 contributors for this article] (2023). Gut microbiota at diagnosis is associated with clinical features and future disease course in Inflammatory Bowel Disease: Data from IBSEN III, a new large Norwegian population-based inception cohort. Journal of Crohn's and Colitis. ISSN 1873-9946. 17, p. i1028–I2029. doi: 10.1093/ecco-jcc/jjac190.1050. Full text in Research Archive
• Tran, Trung; Vaage, Eline Benno; Mehta, Adi; Chopra, Adity; Tietze, Lisa & Kolderup, Heidi Anette [Show all 40 contributors for this article] (2023). Author Correction: Titers of antibodies against ancestral SARS-CoV-2 correlate with levels of neutralizing antibodies to multiple variants (npj Vaccines, (2022), 7, 1, (174), 10.1038/s41541-022-00586-7). npj Vaccines. 8(1). doi: 10.1038/s41541-023-00600-6. Full text in Research Archive
• Fossmark, Reidar; Lirhus, Sandre Svatun & Høivik, Marte Lie (2023). Protonpumpehemmere påvirker forløpet av ulcerøs colitt negativt - En kohortstudie av over 10000 nydiagnostiserte pasienter i Norge. Full text in Research Archive
• Zerouga, Insaf; Sommer, Christine; Carlsen, Monica Hauger; Valeur, Jørgen; Kristensen, Vendel Ailin & Høivik, Marte Lie [Show all 8 contributors for this article] (2023). Kosthold og ernæringsstatus ved nydiagostisert IBD: resultater fra IBSEN III. Full text in Research Archive
• Andersen, Svend; Bernklev, Tomm; Størdal, Ketil; Perminow, Gøri & Høivik, Marte Lie (2022). Paediatric IBD incidence increases in South-East Norway. Full text in Research Archive
• Johansen, Ingunn; Småstuen, Milada Cvancarova; Løkkeberg, Stine Eileen Torp; Kristensen, Vendel Ailin; Høivik, Marte Lie & Lund, Charlotte [Show all 16 contributors for this article] (2022). Symptoms and symptom clusters in patients newly diagnosed with inflammtory bowel disease – results from the IBSEN III study. Full text in Research Archive
• Strande, Vibeke; Småstuen, Milada C.; Lund, Charlotte; Bengtson, May-Bente; Høie, Ole & Cetinkaya, Raziye Boyar [Show all 26 contributors for this article] (2022). Klinisk karakteristika hos nydiagnostiserte pasienter med inflammatorisk tarmsykdom - resultater fra IBSEN III-studien. Full text in Research Archive
• Strande, Vibeke; Småstuen, Milada C; Huppertz-Hauss, Gert; Perminow, Gøri; Henriksen, Magne & Bengtson, May-Bente [Show all 17 contributors for this article] (2022). Fecal calprotectin at diagnosis is associated with oral steroid use first year of inflammatory bowel disease. Full text in Research Archive
• Strande, Vibeke; Småstuen, Milada C.; Hasund, Audun; Huppertz-Hauss, Gert; Pallenschat, Jens & Bengtson, May-Bente [Show all 18 contributors for this article] (2021). Clinical characteristics associated with biochemical remission three months after diagnosis of ulcerative colitis. Full text in Research Archive
• Strande, Vibeke; Småstuen, Milada C.; Hasund, Audun; Huppertz-Hauss, Gert; Pallenschat, Jens & Bengtson, May-Bente [Show all 18 contributors for this article] (2021). Clinical characteristics associated with biochemical remission three months after diagnosis of Crohn's disease. Full text in Research Archive
• Mortensen, Joachim Høg; Lunder, Aida Kapic; Manon-Jensen, Tina; Karsdal, MA; Nielsen, Mette & Leeming, DJ [Show all 13 contributors for this article] (2020). P117 Biomarkers of extracellular matrix remodelling are associated with intestinal fibrosis assessed by magnetic resonance enterography and accumulated intestinal damage (Lémann index): the IBSEN study. Full text in Research Archive
• Kristensen, Vendel Ailin; Lund, Charlotte; Opheim, Randi; Ricanek, Petr; Huppertz-Hauss, Gert & Perminow, Gøri Margrete [Show all 37 contributors for this article] (2020). Inflammatory Bowel Disease in South-Eastern Norway III – IBSEN III. Full text in Research Archive
• Høivik, Marte Lie (2020). Kvinner med IBD - utfordringer gjennom livsløpet. Full text in Research Archive
• Kristensen, Vendel Ailin; Opheim, Randi; Ricanek, Petr; Detlie, Trond Espen; Perminow, Gøri Margrete & Høivik, Marte Lie (2018). IBSEN III—a new population-based inception cohort from South-Eastern Norway. Full text in Research Archive
• Kristensen, Vendel Ailin; Småstuen, Milada Cvancarova; Høivik, Marte Lie; Moum, Bjørn & Vatn, Morten (2018). Long term stability of serological antibodies in a population-based inception cohort of inflammatory bowel disease - The IBSEN study. Full text in Research Archive
• Henriksen, Magne; Jelsness-Jørgensen, Lars-Petter; Høivik, Marte Lie & Moum, Bjørn (2017). Symptomer på irritabel tarmsyndrom (IBS)forekommer hyppig ved ulcerøs kolitt (UC) uavhengig av hvordan remisjon defineres. Resultater fra 20 års oppfølging i IBSEN studien. Full text in Research Archive
• Frigstad, Svein Oskar; Høivik, Marte Lie; Småstuen, Milada C; Jahnsen, Jørgen; Dahl, Sandra Rinne & Berset, Ingrid Prytz [Show all 13 contributors for this article] (2017). Fatigue er ikke assosiert med vitamin D mangel hos IBD pasienter. Full text in Research Archive
• Frigstad, Svein Oskar; Høivik, Marte Lie; Moum, Bjørn; Dahl, Sandra Rinne; Jahnsen, Jørgen & Småstuen, Milada Cvancarova [Show all 12 contributors for this article] (2017). Vitamin D deficiency is not associated with depression in IBD patients. Full text in Research Archive
• Hovde, Øistein; Høivik, Marte Lie; Henriksen, Magne; Solberg, Inger Camilla; Småstuen, Milada Cvancarova & Moum, Bjørn Allan (2017). Corrigendum: Malignancies in Patients with Inflammatory Bowel Disease (IBD): Results from 20 Years of Follow-up in the IBSEN (Inflammatory Bowel South-Eastern Norway) Study. Journal of Crohn's and Colitis. ISSN 1873-9946. 11(12), p. 1511–1511. doi: 10.1093/ecco-jcc/jjw218. Full text in Research Archive
• Frigstad, Svein Oskar; Høivik, Marte Lie; Jahnsen, Jørgen; Dahl, Sandra Rinne; Cvancarova, Milada & Grimstad, Tore [Show all 13 contributors for this article] (2017). Vitamin D deficiency is not associated with depression in IBD patients. Journal of Crohn's and Colitis. ISSN 1873-9946. 11, p. 444–445. doi: 10.1093/ecco-jcc/jjx002.834. Full text in Research Archive
• Frigstad, Svein Oskar; Høivik, Marte Lie; Jahnsen, Jørgen; Småstuen, Milada C; Grimstad, Tore & Berset, Ingrid Prytz [Show all 12 contributors for this article] (2017). Fatigue is not Associated with Vitamin D Deficiency in IBD Patients. Gastroenterology. ISSN 0016-5085. 152(5), p. S945–S945. doi: 10.1016/S0016-5085(17)33218-3. Full text in Research Archive

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