Anne Kristin M. Fell

• Berg, Kristine Karlsrud; Sarjomaa, Marjut; Tveten, Yngvar; Thilesen, Carina Merethe; Fell, Anne Kristin M. & Nordbø, Svein Arne [Show all 8 contributors for this article] (2026). Prevalence of severe fatigue after SARS-CoV-2 infection in Norway: a prospective 2-year follow-up study. BMJ Open. 16(3). doi: 10.1136/bmjopen-2025-104338. Full text in Research Archive Show summary

  Objectives: This study aims to estimate the prevalence of long-lasting severe fatigue and identify possible risk factors in a 2-year follow-up of patients with predominantly mild-to-moderate SARS-CoV-2 infection. Design: Prospective cohort study. Setting A community-based cohort from Telemark and Agder Counties, Norway. Participants A total of 159 PCR-confirmed SARS-CoV-2 positive individuals in the period between 28 February and 17 December 2020 were included at 12 months after SARS-CoV-2 infection, and 93 responded at 24 months follow-up. Outcome: measures Fatigue was assessed using the Fatigue Severity Scale (FSS), and health-related quality of life using the RAND version of health-related quality of life Short Form 36 (SF-36), developed by the RAND Corporation. SARS-CoV-2 antibodies were measured at 12 and 24 months. Results: Severe fatigue (FSS ≥5) was reported by 36% at 12 months and 31% at 24 months. A higher proportion of women than men reported severe fatigue at 12 months (p=0.08). The number of acute-phase symptoms was associated with severe fatigue. No association was found between severe fatigue and anti-SARS-CoV-2 antibody levels, demographic variables or reinfection status. The severe fatigue group scored significantly lower on all domains of SF-36. Conclusion: In this cohort, severe fatigue was common, greatly impacted quality of life and persisted for up to 2 years following SARS-CoV-2 infection. Fatigue severity was associated with symptom burden in the acute phase but not with antibody levels or other demographic variables. These findings underscore the need for long-term follow-up and support for affected individuals.

• Sarjomaa, Marjut Anneli; Berg, Kristine Karlsrud; Jaioun, Keson; Tveten, Yngvar; Kersten, Hege & Reiso, Harald [Show all 12 contributors for this article] (2025). SARS-CoV-2-specific humoral immunity in a Norwegian cohort between 2020 and 2023. BMC Medicine. 23, p. 1–14. doi: 10.1186/s12916-025-04171-2. Full text in Research Archive Show summary

  Background: We have previously reported on natural humoral immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a Norwegian cohort between 2020 and 2021. In this study, we evaluated long-term humoral (including vaccination-induced) immunity in the same cohort and assessed predictors of high antibody levels against spike protein, as well as the persistence of antibodies against the virus spike and nucleocapsid proteins. Methods: Vaccination data and antibody levels against the spike and nucleocapsid proteins were collected at 12 (only in infected participants) and 24 months (in both infected and uninfected participants) after the participants’ first polymerase chain reaction (PCR) tests for the virus. Antibody levels against spike protein at 24 months were categorized as high or low based on the 50th percentile. Possible predictors of high antibody levels against spike protein were examined using univariate and multivariate logistic regression models. Results: Of 1119 original participants (400 PCR + and 719 PCR −), 574 responded to our questionnaires and were invited to antibody measurements (median age: 51 years; women: 59%). Vaccination data showed that 11% were fully immunized, and 85% were booster-immunized at 24 months. Antibody levels were evaluated in 72% (287/400) of the PCR + participants at 12 months and 58% (233/400) at 24 months. At 12 and 24 months, we observed that 97% (278/287) and 100% (233/233), respectively, still had antibodies against the spike protein, and 86% (248/287) and 95% (221/233), respectively, against the nucleocapsid protein. Antibody levels were also evaluated in 34% (247/719) of those in the PCR − group, which revealed that 99.5% and 69% had detectable antibodies against spike and nucleocapsid proteins, respectively, at 24 months. Irrespective of pre-vaccination SARS-CoV-2 infection status, the boosterimmunized participants were 3.7 × more likely to have high antibody levels against spike protein vs the non-boosterimmunized ones. Those aged > 60 years had the highest median antibody levels against the spike protein and were more likely to be booster-immunized. Conclusions: Our findings highlight the benefits of booster vaccinations for humoral immune responses. Long-term antibody levels against the SARS-CoV-2 spike protein were higher in booster-immunized participants vs the nonbooster- immunized, irrespective of pre-vaccination infection status.

• Zivadinovic, Nikola; Jaioun, Keson; Klepaker, Geir; Wagstaff, Anthony Sverre; Torén, Kjell & Henneberger, Paul K. [Show all 9 contributors for this article] (2025). Occupational risk factors for asthma exacerbation in adults: a five-year follow-up of the Norwegian Telemark study cohort. Journal of Asthma. ISSN 0277-0903. 62(9), p. 1608–1615. doi: 10.1080/02770903.2025.2500077. Full text in Research Archive Show summary

  Objectives Asthma exacerbation due to occupational exposure is highly prevalent among adults with asthma. This study assessed the association between occupational risk factors and asthma exacerbation and estimated the impact of asthma exacerbations on job change, sick leave and work ability. Methods In a prospective study of respiratory health in Telemark, Norway, 1857 adult participants with physician-diagnosed asthma were invited to participate in a follow-up survey. Among those who responded, 740 were found eligible for this study. Participants were categorized into overall, mild, and severe asthma exacerbation groups based on self-reports of hospitalization, doctor or emergency visits for breathing difficulties, or increased or new use of lung medications. Logistic regression, adjusted for age, sex, and smoking, was used to assess associations between self-reported asthma exacerbation and exposure to VGDF, job exposure matrix (N-JEM) data, job change, sick leave, and work ability. Results Asthma exacerbation occurred in 140 (19%) responders; 83 had mild exacerbations and 57 severe exacerbations. Severe exacerbation was associated with daily VGDF exposure (OR 2.57, 95% CI 1.15–5.78) and accidental peak exposure to irritants (OR 4.62, 95% CI 1.13–18.85). Both overall and severe exacerbation were associated with job changes (OR 5.40, 1.26–5.65; OR 3.06, 1.16–8.07), sick leave (OR 1.94, 1.33–2.85; OR 2.78, 1.57–4.92), and reduced work ability (OR 1.61, 1.04–2.49; OR 2.17, 1.18–3.98). Conclusion Asthma exacerbation was associated with VGDF exposure and some N-JEM occupational exposures. Reducing workplace exposure may decrease job-change, sick leave, and improve work ability in individuals with asthma exacerbation.

• Fell, Anne Kristin M.; Zhang, Chi; Klepaker, Geir; Abrahamsen, Regine; Zivadinovic, Nikola & Kongerud, Johny Steinar [Show all 9 contributors for this article] (2025). Occupational exposure and chronic bronchitis in a sample of the general population in Telemark, Norway: a two-phased cross-sectional study. Occupational and Environmental Medicine. ISSN 1351-0711. 82(2), p. 98–104. doi: 10.1136/oemed-2024-109641. Full text in Research Archive Show summary

  Objectives: We aimed to estimate the prevalence of chronic bronchitis (CB), examine its association with occupational exposure to irritants assessed by self-reporting or the Nordic job exposure matrix (N-JEM) stratified by smoking status and estimate the population-attributable fraction (PAF) of CB from occupational exposure. Methods: A two-phased, cross-sectional design was used to analyse a random sample collected in 2013 and 2018 of the population aged 16-55 years in Telemark County, Norway. CB was defined as cough and sputum production for ≥3 months over 2 consecutive years. The participants' occupational histories were categorised using the International Standard Classification of Occupations and linked to the N-JEM. Self-reported occupational exposure was also assessed. Logistic regression was performed with adjustments for age, sex and smoking status and yielded ORs, 95% CIs and associated PAFs. Results: Of the 20 282 participants, 5.3% reported CB symptoms. CB was associated with the frequency of self-reported occupational exposure to vapours, gas, dust and fumes (VGDF), with increasing ORs ranging from 1.6 (95% CI 1.3 to 1.9) for seldom to 3.6 (95% CI 2.9 to 4.5) for daily exposure. Among ever-smokers, the N-JEM 'irritants' category was associated with CB (OR 1.4; 95% CI 1.1 to 1.8) to a similar degree as in the group that reported VGDF exposure (OR 2.1; 95% CI 1.7 to 2.5). The PAFs for CB from VGDF exposure were 41% overall, 49% among ever-smokers and 37% among never-smokers. Conclusions: Occupational exposure to VGDF was associated with CB, when self-reported and for smokers when assessed by the N-JEM. Workplace exposure contributed to more than one third of the overall CB burden.

• Zivadinovic, Nikola; Jaioun, Keson; Klepaker, Geir; Wagstaff, Anthony Sverre; Torén, Kjell & Henneberger, Paul K. [Show all 9 contributors for this article] (2024). Occupational exposure and new-onset asthma in the population-based Telemark study: a 5-year follow-up. BMJ Open. 14(9). doi: 10.1136/bmjopen-2024-090131. Full text in Research Archive Show summary

  Objectives: This study aimed to estimate the incidence of asthma and assess the association between job exposure matrix (N-JEM) assigned occupational exposure, self-reported occupational exposure to vapour, gas, dust and fumes (VGDF), mould, damages from moisture and cold, and new-onset asthma. We also aimed to assess the corresponding population attributable fraction (PAF) for ever exposure to VGDF. Design: Longitudinal population-based respiratory health study. Setting: Responders from the baseline Telemark Study in south-eastern Norway were followed up from 2013 to 2018. Participants: 7120 participants, aged 16-55, were followed during a 5-year period. Main outcome measures: New-onset asthma and its association with self-reported occupational exposure to VGDF, data from the N-JEM and self-reported workplace conditions were assessed using logistic regression adjusted for gender, age, smoking and body mass index. The PAF was calculated using the PUNAF command in STATA. Results: There were 266 (3.7%) cases of new-onset asthma and an incidence density of 7.5 cases per 1000 person-years. A statistically significant association was found for ever exposed to VGDF with an OR of 1.49 (95% CI 1.15 to 1.94), weekly OR 2.00 (95% CI 1.29 to 3.11) and daily OR 2.46 (95% CI 1.39 to 4.35) exposure to VGDF. The corresponding PAF for ever exposed to VGDF was 17% (95% CI 5.4% to 27.8%) and the risk of asthma onset increased with frequent VGDF exposure, indicating a possible exposure-response relationship (p=0.002 for trend). The N-JEM exposure group, accidental peak exposure to irritants had an increased risk of new-onset asthma, OR 2.43 (95% CI 1.21 to 4.90). A significant association was also found for self-reported exposure to visible damages due to moisture 1.51 (95% CI 1.08 to 2.11), visible and smell of mould 1.88 (95% CI 1.32 to 2.68), 1.55 (95% CI 1.12 to 2.16) and cold environment 1.41 (95% CI 1.07 to 1.86). Conclusion: Participants had elevated ORs for asthma associated with self-reported and N-JEM-assigned exposures. A PAF of 17% indicates that work-related asthma is still common. The possible exposure-response relationship suggests that reducing occupational VGDF exposure frequency could prevent the onset of asthma.

• Clarhed, Ulrika K.E.; Schiöler, Linus; Torén, Kjell; Fell, Anne Kristin M. & Hellgren, Johan (2024). Women suffering from chronic rhinosinusitis in Norway are more likely to take sick leave. PLOS ONE. 19(11). doi: 10.1371/journal.pone.0313122. Full text in Research Archive
• Sarjomaa, Marjut Anneli; Zhang, Chi; Tveten, Yngvar; Kersten, Hege; Reiso, Harald & Eikeland, Randi [Show all 14 contributors for this article] (2024). Risk factors for SARS-CoV-2 infection: A test-negative case-control study with additional population controls in Norway. BMJ Open. 14(1), p. 1–11. doi: 10.1136/bmjopen-2023-073766. Full text in Research Archive Show summary

  Objectives This study aims to assess risk factors for SARS-CoV-2 infection by combined design; first comparing positive cases to negative controls as determined by PCR testing and then comparing these two groups to an additional prepandemic population control group. Design and setting Test-negative design (TND), multicentre case–control study with additional population controls in South-Eastern Norway. Participants Adults who underwent SARS-CoV-2 PCR testing between February and December 2020. PCR-positive cases, PCR-negative controls and additional age-matched population controls. Primary outcome measures The associations between various risk factors based on self- reported questionnaire and SARS-CoV-2 infection comparing PCR-positive cases and PCR-negative controls. Using subgroup analysis, the risk factors for both PCR-positive and PCR-negative participants were compared with a population control group. Results In total, 400 PCR-positive cases, 719 PCR-negative controls and 14 509 population controls were included. Male sex was associated with the risk of SARS-CoV-2 infection only in the TND study (OR 1.9, 95% CI 1.4 to 2.6), but not when PCR-positive cases were compared with population controls (OR 1.2, 95% CI 0.9. to 1.5). Some factors were positively (asthma, wood heating) or negatively (hypertension) associated with SARS-CoV-2 infection when PCR-positive cases were compared with population controls, but lacked convincing association in the TND study. Smoking was negatively associated with the risk of SARS-CoV-2 infection in both analyses (OR 0.5, 95% CI 0.3 to 0.8 and OR 0.6, 95% CI 0.4 to 0.8). Conclusions Male sex was a possible risk factor for SARS-CoV-2 infection only in the TND study, whereas smoking was negatively associated with SARS-CoV-2 infection in both the TND study and when using population controls. Several factors were associated with SARS-CoV-2 infection when PCR-positive cases were compared with population controls, but not in the TND study, highlighting the strength of combining case–control study designs during the pandemic.

• Klepaker, Geir; Torén, Kjell; Henneberger, Paul Keefer; Kongerud, Johny Steinar & Fell, Anne Kristin M. (2024). Occupational exposure to inhalable agents is associated with reduced work ability: A prospective cohort study in Norway. Journal of Occupational and Environmental Medicine. ISSN 1076-2752. doi: 10.1097/JOM.0000000000003292. Full text in Research Archive Show summary

  Background: This study aimed to assess work ability score (WAS) in 2018 based on self-reported data regarding inhalable occupational exposure and data from a northern European job-exposure matrix (N-JEM) recorded in 2013. Methods: During the 5-year follow-up period of this population-based study, 4423 participants completed a postal questionnaire comprising self-reported questions regarding occupational exposure, work history, and WAS. Results: Ever, weekly, and daily exposure to vapors, gas, dust and fumes (VGDF) in the last 5 years in 2013 was associated with reduced WAS in 2018. The N-JEM data showed that exposure to irritants, wood and paper dust, and mixed agricultural agents were associated with reduced WAS. Conclusions: Exposure to several occupational inhalable substances is associated with reduced work ability. We recommend reducing inhalable occupational exposure to prevent reduced work ability.

• Zivadinovic, Nikola; Abrahamsen, Regine; Pesonen, Maiju; Wagstaff, Anthony Sverre; Torén, Kjell & Henneberger, Paul K. [Show all 8 contributors for this article] (2023). Loss to 5-year follow-up in the population-based Telemark Study: risk factors and potential for bias. BMJ Open. 13(3). doi: 10.1136/bmjopen-2022-064311. Full text in Research Archive Show summary

  Objectives: This study aimed to characterise participants lost to follow-up and identify possible factors associated with non-participation in a prospective population-based study of respiratory health in Norway. We also aimed to analyse the impact of potentially biased risk estimates associated with a high proportion of non-responders. Design: Prospective 5-year follow-up study. Setting: Randomly selected inhabitants from the general population of Telemark County in south-eastern Norway were invited to fill in a postal questionnaire in 2013. Responders in 2013 were followed-up in 2018. Participants: 16 099 participants aged 16-50 years completed the baseline study. 7958 responded at the 5-year follow-up, while 7723 did not. Main outcome measures: χ2 test was performed to compare demographic and respiratory health-related characteristics between those who participated in 2018 and those who were lost to follow-up. Adjusted multivariable logistic regression models were used to assess the relationship between loss to follow-up, background variables, respiratory symptoms, occupational exposure and interactions, and to analyse whether loss to follow-up leads to biased risk estimates. Results: 7723 (49%) participants were lost to follow-up. Loss to follow-up was significantly higher for male participants, those in the youngest age group (16-30 years), those in lowest education level category and among current smokers (all p<0.001). In multivariable logistic regression analysis, loss to follow-up was significantly associated with unemployment (OR 1.34, 95% CI 1.22 to 1.46), reduced work ability (1.48, 1.35 to 1.60), asthma (1.22, 1.10 to 1.35), being woken by chest tightness (1.22, 1.11 to 1.34) and chronic obstructive pulmonary disease (1.81, 1.30 to 2.52). Participants with more respiratory symptoms and exposure to vapour, gas, dust and fumes (VGDF) (1.07 to 1.00-1.15), low-molecular weight (LMW) agents (1.19, 1.00 to 1.41) and irritating agents (1.15, 1.05 to 1.26) were more likely to be lost to follow-up. We found no statistically significant association of wheezing and exposure to LMW agents for all participants at baseline (1.11, 0.90 to 1.36), responders in 2018 (1.12, 0.83 to 1.53) and those lost to follow-up (1.07, 0.81 to 1.42). Conclusion: The risk factors for loss to 5-year follow-up were comparable to those reported in other population-based studies and included younger age, male gender, current smoking, lower educational level and higher symptom prevalence and morbidity. We found that exposure to VGDF, irritating and LMW agents can be risk factors associated with loss to follow-up. Results suggest that loss to follow-up did not affect estimates of occupational exposure as a risk factor for respiratory symptoms.

• Clarhed, Ulrika K. E.; Schiöler, Linus; Torén, Kjell; Fell, Anne Kristin M. & Hellgren, Johan (2022). BMI as a risk factor for the development of chronic rhinosinusitis: a prospective population-based study. European Archives of Oto-Rhino-Laryngology. ISSN 0937-4477. doi: 10.1007/s00405-022-07320-y. Full text in Research Archive Show summary

  Purpose Obesity is a growing, global health problem and previous cross-sectional studies have demonstrated an association between obesity and chronic rhinosinusitis (CRS). There is, however, a lack of prospective studies regarding the impact of obesity on developing (new-onset) CRS. Methods Questionnaire-based data (n = 5769) relating to new-onset CRS and Body Mass Index (BMI) were collected in 2013 and 2018 from the Telemark population study in Telemark, Norway. Odds ratios for the risk of new-onset CRS in 2018 in relation to BMI in 2013 were calculated, adjusted for smoking habits, asthma, gender and age. Results When comparing the group with normal weight (18.5 ≤ BMI < 25) with the obese group (BMI ≥ 30), the odds of new-onset CRS was 53% higher [OR 1.53 (1.11, 2.10)] in the obese group. Conclusion CRS is a multifactorial disease with different phenotypes and it is important to consider obesity when assessing patients with CRS in a clinical setting.

• Bergqvist, Joel; Bove, Mogens; Andersson, Anders; Schiöler, Linus; Klepaker, Geir & Abrahamsen, Regine [Show all 8 contributors for this article] (2022). Chronic rhinosinusitis associated with chronic bronchitis in a five-year follow-up: the Telemark study. BMC Pulmonary Medicine. 22(1). doi: 10.1186/s12890-022-02203-8. Full text in Research Archive Show summary

  Background: Chronic rhinosinusitis (CRS) is associated with generalised airway inflammation. Few studies have addressed the relationship between CRS and chronic bronchitis (CB). Methods: This prospective study over a five-year period aims to investigate the risk of developing CB in subjects reporting CRS at the beginning of the study. A random sample of 7393 adult subjects from Telemark County, Norway, answered a comprehensive respiratory questionnaire in 2013 and then 5 years later in 2018. Subjects reporting CB in 2013 were excluded from the analyses. New cases of CB in 2018 were analysed in relation to having CRS in 2013 or not. Results: The prevalence of new-onset CB in 2018 in the group that reported CRS in 2013 was 11.8%. There was a significant increase in the odds of having CB in 2018 in subjects who reported CRS in 2013 (OR 3.8, 95% CI 2.65-5.40), adjusted for age, sex, BMI, smoking and asthma. Conclusion: In this large population sample, CRS was associated with increased odds of developing CB during a five-year follow-up. Physicians should be aware of chronic bronchitis in patients with CRS.

• Oțelea, Marina Ruxandra; Fell, Anne Kristin M.; Handra, Claudia Mariana; Holm, Mathias; Filon, Francesca Larese & Mijakovski, Dragan [Show all 12 contributors for this article] (2022). The value of fractional exhaled nitric oxide in occupational diseases – a systematic review. Journal of Occupational Medicine and Toxicology. 17(1). doi: 10.1186/s12995-022-00355-1. Full text in Research Archive Show summary

  Fractional exhaled nitric oxide (FeNO) is a non-invasive biomarker of respiratory tract inflammation, originally designated to identify eosinophilic airway inflammation and to predict steroid response. The main field of application of this biomarker is asthma, but FeNO has also been used for other allergic and non-allergic pulmonary disorders such as chronic obstructive pulmonary disease, hypersensitivity pneumonitis and interstitial lung disease. A substantial part of respiratory diseases are related to work, and FeNO, a safe and easy measure to conduct, is a potential valid examination in an occupational setting.This systematic review assesses the value of measuring FeNO related to three types of airborne exposures: allergens, irritants, and respiratory particles inhaled during occupational activities. The review covers results from longitudinal and observational clinical studies, and highlights the added value of this biomarker in monitoring effects of exposure and in the diagnostic criteria of occupational diseases. This review also covers the possible significance of FeNO as an indicator of the efficacy of interventions to prevent work-related respiratory diseases.Initially, 246 articles were identified in PUBMED and SCOPUS. Duplicates and articles which covered results from the general population, symptoms (not disease) related to work, non-occupational diseases, and case reports were excluded. Finally, 39 articles contributed to this review, which led to the following conclusions:a) For occupational asthma there is no consensus on the significant value of FeNO for diagnosis, or on the magnitude of change needed after specific inhalation test or occupational exposure at the workplace. There is some consensus for the optimal time to measure FeNO after exposure, mainly after 24 h, and FeNO proved to be more sensitive than spirometry in measuring the result of an intervention. b) For other occupational obstructive respiratory diseases, current data suggests performing the measurement after the work shift. c) For interstitial lung disease, the evaluation of the alveolar component of NO is probably the most suitable.

• Rui, Francesca; Otelea, Marina; Fell, Anne Kristin M.; Stoleski, Sasho; Mijakoski, D. & Holm, Mathias [Show all 8 contributors for this article] (2022). Occupational Asthma: The Knowledge Needs for a Better Management. Annals of Work Exposures and Health. ISSN 2398-7308. 66(3), p. 287–290. doi: 10.1093/annweh/wxab113. Full text in Research Archive Show summary

  The management of occupational asthma (OA) may be influenced by several factors and removal from exposure is the main tertiary prevention approach, but it is not always feasible without personal and socioeconomic consequences. Reducing the delay between the onset of suggestive symptoms of OA and the diagnosis of OA is associated with a better prognosis. Workers’ education to increase awareness to trigger agents and a medical surveillance program directed especially at at-risk workers could be helpful in reducing this latency time. An early identification of workers who develop rhinitis and conjunctivitis which often precede the onset of asthma symptoms could be important for an early identification of OA. This is particularly important for cases of asthma caused by high-molecular-weight sensitizers and in the early years of employment. The availability of financial support and compensation measures for workers with OA may influence the latency time before diagnosis and, consequently, may influence the OA outcomes. In conclusion, there is a need for high-quality cohort studies that will increase knowledge about risk factor that may influence the timing of diagnosis of OA. This knowledge will be useful for implementation of future surveillance and screening programs in workplaces.

• Klepaker, Geir; Henneberger, Paul Keefer; Torén, Kjell; Brunborg, Cathrine; Kongerud, Johny & Fell, Anne Kristin M. (2022). Association of respiratory symptoms with body mass index and occupational exposure comparing sexes and subjects with and without asthma: follow-up of a Norwegian population study (the Telemark study). BMJ Open Respiratory Research. 9(1), p. 1–10. doi: 10.1136/bmjresp-2021-001186. Full text in Research Archive Show summary

  Background: Occupational exposure and increased body mass index (BMI) are associated with respiratory symptoms. This study investigated whether the association of a respiratory burden score with changes in BMI as well as changes in occupational exposure to vapours, gas, dust and fumes (VGDF) varied in subjects with and without asthma and in both sexes over a 5-year period. Methods: In a 5-year follow-up of a population-based study, 6350 subjects completed a postal questionnaire in 2013 and 2018. A respiratory burden score based on self-reported respiratory symptoms, BMI and frequency of occupational exposure to VGDF were calculated at both times. The association between change in respiratory burden score and change in BMI or VGDF exposure was assessed using stratified regression models. Results: Changes in respiratory burden score and BMI were associated with a β-coefficient of 0.05 (95% CI 0.04 to 0.07). This association did not vary significantly by sex, with 0.05 (0.03 to 0.07) for women and 0.06 (0.04 to 0.09) for men. The association was stronger among those with asthma (0.12; 0.06 to 0.18) compared with those without asthma (0.05; 0.03 to 0.06) (p=0.011). The association of change in respiratory burden score with change in VGDF exposure gave a β-coefficient of 0.15 (0.05 to 0.19). This association was somewhat greater for men versus women, with coefficients of 0.18 (0.12 to 0.24) and 0.13 (0.07 to 0.19), respectively (p=0.064). The estimate was similar among subjects with asthma (0.18; -0.02 to 0.38) and those without asthma (0.15; 0.11 to 0.19). Conclusions: Increased BMI and exposure to VGDF were associated with increased respiratory burden scores. The change due to increased BMI was not affected by sex, but subjects with asthma had a significantly larger change than those without. Increased frequency of VGDF exposure was associated with increased respiratory burden score but without statistically significant differences with respect to sex or asthma status.

• Riise, Geir; Fell, Anne Kristin M. & Røed, Maren Anne (2022). Klimaendringer og helse. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 142(12). doi: 10.4045/tidsskr.22.0326. Full text in Research Archive
• Sarjomaa, Marjut Anneli; Diep, Lien My; Zhang, Chi; Tveten, Yngvar; Reiso, Harald & Thilesen, Carina [Show all 14 contributors for this article] (2022). SARS-CoV-2 antibody persistence after five and twelve months: A cohort study from South-Eastern Norway. PLOS ONE. 17(8), p. 1–15. doi: 10.1371/journal.pone.0264667. Full text in Research Archive Show summary

  Objectives: To assess total antibody levels against Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS CoV-2) spike protein up to 12 months after Coronavirus Disease (COVID-19) infection in non-vaccinated individuals and the possible predictors of antibody persistence. Methods: This is the first part of a prospective multi-centre cohort study. Participants: The study included SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) positive and negative participants in South-Eastern Norway from February to December 2020. Possible predictors of SARS-CoV-2 total antibody persistence was assessed. The SARS-CoV-2 total antibody levels against spike protein were measured three to five months after PCR in 391 PCR-positive and 703 PCR-negative participants; 212 PCR-positive participants were included in follow-up measurements at 10 to 12 months. The participants completed a questionnaire including information about symptoms, comorbidities, allergies, body mass index (BMI), and hospitalisation. Primary outcome: The SARS-CoV-2 total antibody levels against spike protein three to five and 10 to 12 months after PCR positive tests. Results: SARS-CoV-2 total antibodies against spike protein were present in 366 (94%) non-vaccinated PCR-positive participants after three to five months, compared with nine (1%) PCR-negative participants. After 10 to 12 months, antibodies were present in 204 (96%) non-vaccinated PCR-positive participants. Of the PCR-positive participants, 369 (94%) were not hospitalised. The mean age of the PCR-positive participants was 48 years (SD 15, range 20-85) and 50% of them were male. BMI ≥ 25 kg/m2 was positively associated with decreased antibody levels (OR 2.34, 95% CI 1.06 to 5.42). Participants with higher age and self-reported initial fever with chills or sweating were less likely to have decreased antibody levels (age: OR 0.97, 95% CI 0.94 to 0.99; fever: OR 0.33, 95% CI 0.13 to 0.75). Conclusion: Our results indicate that the level of SARS-CoV-2 total antibodies against spike protein persists for the vast majority of non-vaccinated PCR-positive persons at least 10 to 12 months after mild COVID-19.

• Bortoli, Marit Müller De; Oellingrath, Inger Margaret; Fell, Anne Kristin Møller; Burdorf, Alex & Robroek, Suzan (2021). Influence of lifestyle risk factors on work ability and sick leave in a general working population in Norway: a 5-year longitudinal study. BMJ Open. 11(2). doi: 10.1136/bmjopen-2020-045678. Full text in Research Archive Show summary

  Objectives: The aim of this study is to assess (1) whether lifestyle risk factors are related to work ability and sick leave in a general working population over time, and (2) these associations within specific disease groups (ie, respiratory diseases, cardiovascular disease and diabetes, and mental illness). Setting: Telemark county, in the south-eastern part of Norway. Design: Longitudinal study with 5 years follow-up. Participants: The Telemark study is a longitudinal study of the general working population in Telemark county, Norway, aged 16 to 50 years at baseline in 2013 (n=7952) and after 5-year follow-up. Outcome measure: Self-reported information on work ability (moderate and poor) and sick leave (short-term and long-term) was assessed at baseline, and during a 5-year follow-up. Results: Obesity (OR=1.64, 95% CI: 1.32 to 2.05) and smoking (OR=1.62, 95% CI: 1.35 to 1.96) were associated with long-term sick leave and, less strongly, with short-term sick leave. An unhealthy diet (OR=1.57, 95% CI: 1.01 to 2.43), and smoking (OR=1.67, 95% CI: 1.24 to 2.25) were associated with poor work ability and, to a smaller extent, with moderate work ability. A higher lifestyle risk score was associated with both sick leave and reduced work ability. Only few associations were found between unhealthy lifestyle factors and sick leave or reduced work ability within disease groups. Conclusion: Lifestyle risk factors were associated with sick leave and reduced work ability. To evaluate these associations further, studies assessing the effect of lifestyle interventions on sick leave and work ability are needed.

• Klepaker, Geir; Henneberger, Paul Keefer; Hertel, Jens Kristoffer; Holla, Øystein Lunde; Kongerud, Johny & Fell, Anne Kristin Møller (2021). Influence of asthma and obesity on respiratory symptoms, work ability and lung function: findings from a cross-sectional Norwegian population study. BMJ Open Respiratory Research. doi: 10.1136/bmjresp-2021-000932. Full text in Research Archive Show summary

  Background: Although asthma and obesity are each associated with adverse respiratory outcomes, a possible interaction between them is less studied. This study assessed the extent to which asthma and overweight/obese status were independently associated with respiratory symptoms, lung function, Work Ability Score (WAS) and sick leave; and whether there was an interaction between asthma and body mass index (BMI) ≥25 kg/m2 regarding these outcomes. Methods: In a cross-sectional study, 626 participants with physician-diagnosed asthma and 691 without asthma were examined. All participants completed a questionnaire and performed spirometry. The association of outcome variables with asthma and BMI category were assessed using regression models adjusted for age, sex, smoking status and education. Results: Asthma was associated with reduced WAS (OR=1.9 (95% CI 1.4 to 2.5)), increased sick leave in the last 12 months (OR=1.4 (95% CI 1.1 to 1.8)) and increased symptom score (OR=7.3 (95% CI 5.5 to 9.7)). Obesity was associated with an increased symptom score (OR=1.7 (95% CI 1.2 to 2.4)). Asthma was associated with reduced prebronchodilator and postbronchodilator forced expiratory volume in 1 s (FEV1) (β=-6.6 (95% CI -8.2 to -5.1) and -5.2 (95% CI -6.7 to -3.4), respectively) and prebronchodilator forced vital capacity (FVC) (β=-2.3 (95% CI -3.6 to -0.96)). Obesity was associated with reduced prebronchodilator and postbronchodilator FEV1 (β=-2.9 (95% CI -5.1 to -0.7) and -2.8 (95% CI -4.9 to -0.7), respectively) and FVC (-5.2 (95% CI -7.0 to -3.4) and -4.2 (95% CI -6.1 to -2.3), respectively). The only significant interaction was between asthma and overweight status for prebronchodilator FVC (β=-3.6 (95% CI -6.6 to -0.6)). Conclusions: Asthma and obesity had independent associations with increased symptom scores, reduced prebronchodilator and postbronchodilator FEV1 and reduced prebronchodilator FVC. Reduced WAS and higher odds of sick leave in the last 12 months were associated with asthma, but not with increased BMI. Besides a possible association with reduced FVC, we found no interactions between asthma and increased BMI.

• Bortoli, Marit Müller De; Fell, Anne Kristin Møller; Svendsen, Martin Veel; Henneberger, Paul K; Kongerud, Johny & Oellingrath, Inger Margaret (2020). Lifestyle, sick leave and work ability among Norwegian employees with asthma?A population-based cross-sectional survey conducted in Telemark County, Norway. PLOS ONE. 15(4). doi: 10.1371/journal.pone.0231710. Full text in Research Archive Show summary

  Objective To investigate whether physician-diagnosed asthma modifies the associations between multiple lifestyle factors, sick leave and work ability in a general working population. Methods A cross-sectional study was conducted in Telemark County, Norway, in 2013. A sample of 16 099 respondents completed a self-administered questionnaire. We obtained complete data on lifestyle, work ability and sick leave for 10 355 employed persons aged 18–50 years. We modelled sick leave and work ability using multiple logistic regression, and introduced interaction terms to investigate whether associations with lifestyle factors were modified by asthma status. Results Several lifestyle risk factors and a multiple lifestyle risk index were associated with sick leave and reduced work ability score among persons both with and without physician-diagnosed asthma. A stronger association between lifestyle and sick leave among persons with asthma was confirmed by including interaction terms in the analysis: moderate lifestyle risk score * asthma OR = 1.4 (95% CI 1.02–2.1); high lifestyle risk score * asthma OR = 1.6 (95% CI 1.1–2.3); very high lifestyle risk score * asthma OR = 1.6 (95% CI 0.97–2.7); obesity * asthma OR = 1.5 (95% CI 1.02–2.1); past smoking * asthma OR = 1.4 (95% CI 1.01–1.9); and current smoking * asthma OR = 1.4 (95% CI 1.03–2.0). There was no significant difference in the association between lifestyle and work ability score among respondents with and without asthma. Conclusions In the present study, we found that physician-diagnosed asthma modified the association between lifestyle risk factors and sick leave. Asthma status did not significantly modify these associations with reduced work ability score. The results indicate that lifestyle changes could be of particular importance for employees with asthma.

• Oellingrath, Inger Margaret; Svendsen, Martin Veel & Fell, Anne Kristin Møller (2020). Combined body mass index and abdominal obesity, lifestyle and health in a Norwegian adult population: a cross-sectional study. Journal of Public Health (Berlin). ISSN 2198-1833. p. 1–8. doi: 10.1007/s10389-020-01259-2. Full text in Research Archive Show summary

  Aim This study aimed to determine the prevalence of combined body mass index and waist circumference (BMI-WC) disease risk categories in a Norwegian adult population aged 18–51 years and describe selected health indicators (lifestyle factors, medical conditions, self-perceived health and high sensitive serum C-reactive protein (hs-CRP)) within these categories. Subjects and methods A sample of 1318 adults (aged 18–51 years) answered a comprehensive questionnaire covering lifestyle factors, medical conditions, self-perceived health and background variables in the population-based cross-sectional Telemark study, Norway, 2014–2015. BMI, WC and hs-CRP were determined as part of a broader medical examination. Four combined BMI-WC risk categories were constructed, based on recommendations provided by the US National Institutes of Health (NIH), and associations with health indicators examined using multiple logistic regression analyses. Results More than half of the participants represented combined BMI-WC categories with elevated disease risk (27% with increased risk, 11% with high risk and 19% with very high risk). Unfavourable health indicators (low physical activity, cardiovascular disease (CVD) history, physician-diagnosed high blood pressure and diabetes, lowered self-perceived health and elevated hs-CRP) increased in line with BMI-WC disease risk. Associations were observed independent of gender, age, education level and residential area. Conclusion The findings highlight the importance of using both BMI categories and WC for personalised assessment of obesity-related risk and need for follow-up. The findings are considered relevant to public health intervention programmes targeting adults with overweight and obesity. Follow-up studies are warranted to study morbidity development in the BMI-WC risk categories.

• Clarhed, Ulrika K E; Johansson, Helena; Svendsen, Martin Veel; Torén, Kjell; Fell, Anne Kristin Møller & Hellgren, Johan (2020). Occupational exposure and the risk of new-onset chronic rhinosinusitis - a prospective study 2013-2018. Rhinology. ISSN 0300-0729. doi: 10.4193/Rhin20.104. Full text in Research Archive Show summary

  Background: The aetiology behind chronic rhinosinusitis (CRS) is still poorly understood. The aim of this study was to investigate the association between the onset of CRS and several common occupational exposures over time. Methodology: An adult random population from Telemark, Norway, comprising 7,952 subjects, who answered a comprehensive respiratory questionnaire including questions on CRS and occupational exposure first in 2013 and again in 2018. Results: New-onset CRS during the five-year follow-up was independently associated with occupational exposure to hair-care products, cleaning agents among women, super glue, strong acids, cooking fumes and wood dust. Conclusion: In this random population cohort from Norway, exposure to several common occupational agents, such as hair-care products, super glue and wood dust, was associated with the onset of CRS. It is important that physicians who see patients with CRS inquire about workplace exposure.

• Abrahamsen, Regine; Gundersen, Gølin Finkenhagen; Svendsen, Martin Veel; Klepaker, Geir; Kongerud, Johny & Fell, Anne Kristin Møller (2020). Possible Risk Factors for Poor Asthma Control Assessed in a Cross-Sectional Population-Based Study From Telemark, Norway. PLOS ONE. 15(5). doi: 10.1371/journal.pone.0232621. Full text in Research Archive Show summary

  This cross-sectional study of the general population of Telemark County, Norway, aimed to identify risk factors associated with poor asthma control as defined by the Asthma Control Test (ACT), and to determine the proportions of patients with poorly controlled asthma who had undergone spirometry, used asthma medication, or been examined by a pulmonary physician. In 2014-2015, the study recruited 326 subjects aged 16-50 years who had self-reported physician-diagnosed asthma and presence of respiratory symptoms during the previous 12 months. The clinical outcome measures were body mass index (BMI), forced vital capacity (FVC) and forced expiratory volume in one second (FEV1), fractional exhaled nitric oxide (FeNO), immunoglobulin E (IgE) in serum and serum C-reactive protein (CRP). An ACT score ≤ 19 was defined as poorly controlled asthma. Overall, 113 subjects (35%) reported poor asthma control. The odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with poorly controlled asthma were: self-reported occupational exposure to vapor, gas, dust, or fumes during the previous 12 months (OR 2.0; 95% CI 1.1-3.6), body mass index ≥ 30 kg/m2 (OR 2.2; 95% CI 1.2-4.1), female sex (OR 2.6; 95% CI 1.5-4.7), current smoking (OR 2.8; 95% CI 1.5-5.3), and past smoking (OR 2.3; 95% CI 1.3-4.0). Poor asthma control was also associated with reduced FEV1 after bronchodilation (β -3.6; 95% CI -7.0 to -0.2). Moreover, 13% of the participants with poor asthma control reported no use of asthma medication, 51% had not been assessed by a pulmonary physician, and 20% had never undergone spirometry. Because these data are cross-sectional, further studies assessing possible risk factors in general and objectively measured occupational exposure in particular are needed. However, our results suggest that there is room for improvement with regards to use of spirometry and pulmonary physician referrals when a patient's asthma is inadequately controlled.

• Klepaker, Geir; Svendsen, Martin Veel; Hertel, Jens Kristoffer; Holla, Øystein Lunde; Henneberger, Paul Keefer & Kongerud, Johny [Show all 7 contributors for this article] (2019). Influence of Obesity on Work ability, Respiratory Symptoms, and Lung Function in Adults with Asthma. Respiration. ISSN 0025-7931. 98(6), p. 473–481. doi: 10.1159/000502154. Full text in Research Archive Show summary

  BACKGROUND:Asthma is defined by variable respiratory symptoms and lung function, and may influence work ability. Similarly, obesity may contribute to respiratory symptoms, affect lung function, and reduce work ability. Thus, assessment of the influence of obesity on work ability, respiratory symptoms, and lung function in adults with asthma is needed. OBJECTIVES:We hypothesized that patients with obesity and asthma have more respiratory symptoms and reduced work ability and lung function compared with normal-weight patients with asthma. METHODS:We examined 626 participants with physician-diagnosed asthma, aged 18-52 years, recruited from a cross-sectional general population study using a comprehensive questionnaire including work ability score, the asthma control test (ACT), height and weight, and spirometry with reversibility testing. RESULTS:Participants with a body mass index (BMI) ≥30 kg/m2 (i.e., obese) had a higher symptom score (OR 1.78, 95% CI 1.14-2.80), current use of asthma medication (1.60, 1.05-2.46), and incidence of ACT scores ≤19 (poor asthma control) (1.81, 1.03-3.18) than participants with BMI ≤24.9 kg/m2 (i.e., normal weight). Post-bronchodilator forced vital capacity (FVC) as a percentage of predicted (β coefficient -4.5) and pre-bronchodilator forced expiratory volume in 1 s as a percentage of predicted (FEV1) (β coefficient -4.6) were negatively associated with BMI ≥30 kg/m2. We found no statistically significant association of BMI >30 kg/m2 (compared to BMI <24.9 kg/m2) with sick leave (1.21, 0.75-1.70) or reduced work ability (1.23, 0.74-2.04). CONCLUSIONS:There were indications that patients with obesity had a higher symptom burden, poorer asthma control, higher consumption of asthma medication, and reduced lung function, in particular for FVC, compared with normal-weight patients.

• Hegseth, Marit Nøst; Oftedal, Bente Margaret; Höper, Anje Christina; Aminoff, Anna Louise; Thomassen, Marte Renate & Svendsen, Martin Veel [Show all 7 contributors for this article] (2019). Self-reported traffic-related air pollution and respiratory symptoms among adults in an area with modest levels of traffic. PLOS ONE. 14(12), p. 1–19. doi: 10.1371/journal.pone.0226221. Full text in Research Archive Show summary

  Health effects of traffic-related air pollution (TRAP) concentrations in densely populated areas are previously described. However, there is still a lack of knowledge of the health effects of moderate TRAP levels. The aim of the current study, a population-based survey including 16 099 adults (response rate 33%), was to assess the relationship between TRAP estimates and respiratory symptoms in an area with modest levels of traffic; Telemark County, Norway. Respondents reported respiratory symptoms the past 12 months and two TRAP exposure estimates: <i>amount of traffic outside their bedroom window and time spent by foot daily along a moderate to heavy traffic road</i>. Females reported on average more symptoms than males. Significant relationships between <i>traffic outside their bedroom window</i> and number of symptoms were only found among females, with the strongest associations among female occasional smokers (incidence rate ratio [IRR], 1.75, 95% confidence interval (CI) [1.16–2.62] for moderate or heavy traffic compared to no traffic). Significant relationship between <i>time spent daily by foot along a moderate to heavy traffic road</i> and number of symptoms was found among male daily smokers (IRR 1.09, 95% CI [1.04–1.15] per hour increase). Associations between <i>traffic outside bedroom window</i> and each respiratory symptom were found. Significant associations were primarily detected among females, both among smokers and non-smokers. Significant associations between <i>time spent by foot daily along a moderate to heavy traffic road</i> (per hour) and <i>nocturnal dyspnoea</i> (odds ratio (OR) 1.20, 95% CI [1.05–1.38]), <i>nocturnal chest tightness</i> (OR 1.13 [1.00–1.28]) and <i>wheezing</i> (OR 1.14 [1.02–1.29]) were found among daily smokers, primarily men. Overall, we found significant associations between self-reported TRAP exposures and respiratory symptoms. Differences between genders and smoking status were identified. The findings indicate an association between TRAP and respiratory symptoms even in populations exposed to modest levels of TRAP.

• Oellingrath, Inger Margaret; Bortoli, Marit Müller De; Svendsen, Martin Veel & Fell, Anne Kristin Møller (2019). Lifestyle and work ability in a general working population in Norway: a cross-sectional study. BMJ Open. 9(4). doi: 10.1136/bmjopen-2018-026215. Full text in Research Archive Show summary

  Objectives The aim of this study was to investigate the association between multiple lifestyle-related risk factors (unhealthy diet, low leisure-time physical activity, overweight/obesity and smoking) and self-rated work ability in a general working population. Setting Population-based cross-sectional study, in Telemark County, Norway, 2013. Participants A random sample of 50 000 subjects was invited to answer a self-administered questionnaire and 16 099 responded. Complete data on lifestyle and work ability were obtained for 10 355 participants aged 18–50 years all engaged in paid work during the preceding 12 months. Outcome measure Work ability was assessed using the Work Ability Score (WAS)—the first question in the Work Ability Index. To study the association between multiple lifestyle risk factors and work ability, a lifestyle risk index was constructed and relationships examined using multiple logistic regression analysis. Results Low work ability was more likely among subjects with an unhealthy diet (ORadj 1.3, 95% CI 1.02 to 1.5), inactive persons (ORadj 1.4, 95% CI 1.2 to 1.6), obese respondents (ORadj 1.5, 95% CI 1.3 to 1.7) and former and current smokers (ORadj 1.2, 95% CI 1.1 to 1.4 and 1.3, 95% CI 1.2 to 1.5, respectively). An additive relationship was observed between the lifestyle risk index and the likelihood of decreased work ability (moderate-risk score: ORadj 1.3; 95% CI 1.1 to 1.6; high-risk score: ORadj 1.9; 95% CI 1.6 to 2.2; very high risk score: ORadj 2.4; 95% CI 1.9 to 3.0). The overall population attributable fraction (PAF) of low work ability based on the overall risk index was 38%, while the PAFs of physical activity, smoking, body mass index and diet were 16%, 11%, 11% and 6%, respectively. Conclusions Lifestyle risk factors were associated with low work ability. An additive relationship was observed. The findings are considered relevant to occupational intervention programmes aimed at prevention and improvement of decreased work ability.

• Clarhed, Ulrika K E; Svendsen, Martin Veel; Schiöler, Linus; Kongerud, Johny; Torén, Kjell & Hellgren, Johan [Show all 7 contributors for this article] (2018). Chronic Rhinosinusitis Related to Occupational Exposure: The Telemark Population Study. Journal of Occupational and Environmental Medicine. ISSN 1076-2752. 60(7), p. 656–660. doi: 10.1097/JOM.0000000000001312. Full text in Research Archive Show summary

  Objective: The aim of this study was to investigate the association between occupational exposure and chronic rhinosinusitis. Methods: A random population from the region of Telemark, aged 16 to 50 years, answered a respiratory questionnaire including questions on chronic rhinosinusitis and exposure in the occupational environment. Results: A total of 16,099/48,142 subjects responded. The prevalence of chronic rhinosinusitis was 9%. Exposure associated with chronic rhinosinusitis comprised paper dust [odds ratio (OR) 1.3, 95% confidence interval (95% CI) 1.1 to 1.5], cleaning agents (OR 1.2, 95% CI 1.0 to 1.3), metal dust (OR 1.3, 95% CI 1.1 to 1.6), animals (OR 1.2, 95% CI 1.0 to 1.5), moisture/mould/mildew (OR 1.3, 95% CI 1.1 to 1.5), and physically strenuous work (OR 1.4, 95% CI 1.2 to 1.7). Conclusion: Occupational exposure to paper dust, cleaning agents, metal dust, animals, moisture/mould/mildew, and physically strenuous work was independently related to having chronic rhinosinusitis. An occupational history should be reviewed when assessing patients with chronic rhinosinusitis.

• Fell, Anne Kristin Møller; Svendsen, Martin Veel; Kim, J L; Abrahamsen, Regine; Henneberger, Paul K. & Toren, K. [Show all 8 contributors for this article] (2018). Exposure to second-hand tobacco smoke and respiratory symptoms in non-smoking adults: cross-sectional data from the general population of Telemark, Norway. BMC Public Health. 18(1). doi: 10.1186/s12889-018-5771-4. Full text in Research Archive Show summary

  Background In Norway, data on the association between second-hand tobacco smoke (SHS) exposure at home and respiratory symptoms in adults are limited. Methods We assessed the association between self-reported exposure to SHS and the prevalence of respiratory symptoms among never-smokers aged 16 to 50 years from the general population who were included in a cross-sectional population-based study in Telemark County, Norway. Logistic regression analysis was used to estimate the odds ratios of symptoms among 8850 never-smokers who provided an affirmative response to questions regarding SHS; 504 (5.7%) of these reported that they lived in a home with daily or occasional indoor smoking. Results Productive cough and nocturnal dyspnoea were statistically associated with daily SHS exposure (ORs 1.5 [95% CI 1.04–2.0] and 1.8 [1.2–2.7], respectively). In analyses stratified by gender, nocturnal dyspnoea was associated with SHS among women (OR 1.8 [1.1–3.1]), but not among men (OR 0.93 [0.49–1.8]). Symptoms were not associated with occasional SHS exposure in the entire group, but infrequent exposure among men only was associated with increased prevalence of chronic cough; (OR 1.6; [1.04–2.6]) and was negatively associated with wheeze; (OR 0.44 [0.21–0.92)]. Conclusions Daily SHS exposure in private homes was associated with productive cough and nocturnal dyspnoea. Our results suggest that preventive measures may be needed to reduce the respiratory effects of SHS at home. Trial registration ClinicalTrials.gov Identifier: NCT02073708 Registered February 27. 2014.

• Fell, Anne Kristin Møller & Nordby, Karl-Christian (2017). Association between exposure in the cement production industry and non-malignant respiratory effects: A systematic review. BMJ Open. 7(4). doi: 10.1136/bmjopen-2016-012381. Full text in Research Archive Show summary

  Objectives: Based on findings from a systematic literature search, we present and discuss the evidence for an association between exposure to cement dust and non-malignant respiratory effects in cement production workers. Design and setting: Systematic literature searches (MEDLINE and Embase) were performed. Outcomes were restricted to respiratory symptoms, lung function indices, asthma, chronic bronchitis, chronic obstructive pulmonary disease, pneumoconiosis, induced sputum or fraction of exhaled nitric oxide (FeNO) measurements. Participants: The studies included exposed cement production workers and non-exposed or low-exposed referents. Primary and secondary outcomes: The searches yielded 594 references, and 26 articles were included. Cross-sectional studies show reduced lung function levels at or above 4.5 mg/m3 of total dust and 2.2 mg/m3 of respiratory dust. ORs for symptoms ranged from 1.2 to 4.8, while FEV1/FVC was 1–6% lower in exposed than in controls. Cohort studies reported a high yearly decline in FEV1/FVC ranging from 0.8% to 1.7% for exposed workers. 1 longitudinal study reported airflow limitation at levels of exposure comparable to ∼1 mg/m3 respirable and 3.7–5.4 mg/m3 total dust. A dose–response relationship between exposure and decline in lung function has only been shown in 1 cohort. 2 studies have detected small increases in FeNO levels during a work shift; 1 study reported signs of airway inflammation in induced sputum, whereas another did not detect an increase in hospitalisation rates. Conclusions: Lack of power, adjustment for possible confounders and other methodological issues are limitations of many of the included studies. Hence, no firm conclusions can be drawn. There are few longitudinal data, but recent studies report a dose–response relationship between cement production dust exposure and declining lung function indicating a causal relationship, and underlining the need to reduce exposure among workers in this industry.

• Namløs, Gry Beate; Busk, Øyvind; Tveten, Kristian; Hanevik, Hans Ivar; Fell, Anne Kristin Møller & Hjelmesæth, Jøran [Show all 8 contributors for this article] (2017). Next-generation sequencing of the monogenic obesity genes LEP, LEPR, MC4R, PCSK1 and POMC in a Norwegian cohort of patients with morbid obesity and normal weight controls. Molecular Genetics and Metabolism. ISSN 1096-7192. 121(1), p. 51–56. doi: 10.1016/j.ymgme.2017.03.007. Full text in Research Archive
• Abrahamsen, Regine; Fell, Anne Kristin Møller; Svendsen, Martin Veel; Andersson, E.; Torén, Kjell & Henneberger, Paul K. [Show all 7 contributors for this article] (2017). Association of respiratory symptoms and asthma with occupational exposures: findings from a population-based cross-sectional survey in Telemark, Norway. BMJ Open. 7(3). doi: 10.1136/bmjopen-2016-014018. Full text in Research Archive Show summary

  Objectives The aim of this study was to estimate the prevalence of respiratory symptoms and physician-diagnosed asthma and assess the impact of current occupational exposure. Design Cross-sectional analyses of the prevalence of self-reported respiratory health and association with current occupational exposure in a random sample of the general population in Telemark County, Norway. Settings In 2013, a self-administered questionnaire was mailed to a random sample of the general population, aged 16–50, in Telemark, Norway. The overall response rate was 33%, comprising 16 099 responders. Outcome measures The prevalence for respiratory symptoms and asthma, and OR of respiratory symptoms and asthma for occupational groups and exposures were calculated. Occupational exposures were assessed using self-reported exposure and an asthma-specific job-exposure matrix (JEM). Results The prevalence of physician-diagnosed asthma was 11.5%. For the occupational groups, the category with agriculture/fishery workers and craft/related trade workers was associated with wheezing and asthma attack in the past 12 months, showing OR 1.3 (1.1 to 1.6) and 1.9 (1.2 to 2.8), respectively. The group including technicians and associated professionals was also associated with wheezing OR 1.2 (1.0 to 1.3) and asthma attack OR 1.4 (1.1 to 1.9). The JEM data show that exposure to flour was associated with wheezing OR 3.2 (1.4 to 7.3) and woken with dyspnoea OR 3.5 (1.3 to 9.5), whereas exposures to diisocyanates, welding/soldering fumes and exposure to vehicle/motor exhaust were associated with dyspnoea OR 2.9 (1.5 to 5.7), 3.2 (1.6 to 6.4) and 1.4 (1.0 to 1.8), respectively. Conclusions The observed prevalence of physician-diagnosed asthma was 11.5%. The ‘manual’ occupations were associated with respiratory symptoms. Occupational exposure to flour, diisocyanates, welding/soldering fumes and vehicle/motor exhaust was associated with respiratory symptoms in the past 12 months and use of asthma medication. However, prospective data are needed to confirm the observed associations.

• Nordby, Karl-Christian; Notø, Hilde Pettersen; Wijnand, Eduard; Skogstad, Marit; Fell, Anne Kristin Møller & Thomassen, Yngvar [Show all 12 contributors for this article] (2016). Thoracic dust exposure is associated with lung function decline in cement production workers. European Respiratory Journal. ISSN 0903-1936. 48(2), p. 331–339. doi: 10.1183/13993003.02061-2015. Full text in Research Archive Show summary

  We hypothesised that exposure to workplace aerosols may lead to lung function impairment among cement production workers. Our study included 4966 workers in 24 cement production plants. Based on 6111 thoracic aerosol samples and information from questionnaires we estimated arithmetic mean exposure levels by plant and job type. Dynamic lung volumes were assessed by repeated spirometry testing during a mean follow-up time of 3.5 years (range 0.7–4.6 years). The outcomes considered were yearly change of dynamic lung volumes divided by the standing height squared or percentage of predicted values. Statistical modelling was performed using mixed model regression. Individual exposure was classified into quintile levels limited at 0.09, 0.89, 1.56, 2.25, 3.36, and 14.6 mg·m−3, using the lowest quintile as the reference. Employees that worked in administration were included as a second comparison group. Exposure was associated with a reduction in forced expiratory volume in 1 s (FEV1), forced expiratory volume in 6 s and forced vital capacity. For FEV1 % predicted a yearly excess decline of 0.84 percentage points was found in the highest exposure quintile compared with the lowest. Exposure at the higher levels found in this study may lead to a decline in dynamic lung volumes. Exposure reduction is therefore warranted.

• Fell, Anne Kristin Møller; Eikeland, Randi & Aaseth, Jan (2016). En kvinne i 30-årene med hoste, tremor, uro og synsforstyrrelser. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 136(14-15), p. 1233–1235. doi: 10.4045/tidsskr.15.0998. Full text in Research Archive Show summary

  I 1970-årene kontaktet en kvinne som da var i 30-årene lege på grunn av intermitterende luftveisplager, økende tretthet, uro og synsforstyrrelser. Hun utviklet et sammensatt sykdomsbilde med symptomer fra flere organsystemer. Det skulle gå mer enn 30 år før den sannsynlige årsaken til plagene var identifisert.

• Abrahamsen, Regine; Svendsen, Martin Veel; Henneberger, Paul K.; Gundersen, Gølin Finkenhagen; Torén, Kjell & Kongerud, Johny [Show all 7 contributors for this article] (2016). Non-response in a cross-sectional study of respiratory health in Norway. BMJ Open. 6(1). doi: 10.1136/bmjopen-2015-009912. Full text in Research Archive
• Roth, Steffen & Fell, Anne Kristin Møller (2016). Multiple subcutaneous granulomas and severe rhinitis after intradermal deposition of epoxy: A case report. Journal of Occupational Medicine and Toxicology. 11(30). doi: 10.1186/s12995-016-0120-y. Full text in Research Archive
• Fell, Anne Kristin Møller; Abrahamsen, Regine; Henneberger, Paul K; Svendsen, Martin Veel; Andersson, E. & Toren, K. [Show all 7 contributors for this article] (2016). Breath-taking jobs: a case-control study of respiratory work disability by occupation in Norway. Occupational and Environmental Medicine. ISSN 1351-0711. 73(9), p. 600–606. doi: 10.1136/oemed-2015-103488. Full text in Research Archive Show summary

  Background The current knowledge on respiratory work disability is based on studies that used crude categories of exposure. This may lead to a loss of power, and does not provide sufficient information to allow targeted workplace interventions and follow-up of patients with respiratory symptoms. Objectives The aim of this study was to identify occupations and specific exposures associated with respiratory work disability. Methods In 2013, a self-administered questionnaire was mailed to a random sample of the general population, aged 16–50, in Telemark County, Norway. We defined respiratory work disability as a positive response to the survey question: ‘Have you ever had to change or leave your job because it affected your breathing?’ Occupational exposures were assessed using an asthma-specific job-exposure matrix, and comparison of risks was made for cases and a median of 50 controls per case. Results 247 workers had changed their work because of respiratory symptoms, accounting for 1.7% of the respondents ever employed. The ‘breath-taking jobs’ were cooks/chefs: adjusted OR 3.6 (95% CI 1.6 to 8.0); welders: 5.2 (2.0 to 14); gardeners: 4.5 (1.3 to 15); sheet metal workers: 5.4 (2.0 to 14); cleaners: 5.0 (2.2 to 11); hairdressers: 6.4 (2.5 to 17); and agricultural labourers: 7.4 (2.5 to 22). Job changes were also associated with a variety of occupational exposures, with some differences between men and women. Conclusions Self-report and job-exposure matrix data showed similar findings. For the occupations and exposures associated with job change, preventive measures should be implemented.

• Fell, Anne Kristin Møller; Aasen, Tor Olav Brøvig & Kongerud, Johny (2014). Arbeidsrelatert kols. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 134(22), p. 2158–2163. doi: 10.4045/tidsskr.14.0255. Full text in Research Archive
• Nordby, Karl-Christian; Fell, Anne Kristin Møller; Notø, Hilde Pettersen; Wijnand, Eduard; Skogstad, Marit & Thomassen, Yngvar [Show all 9 contributors for this article] (2011). Exposure to thoracic dust, airway symptoms, and lung function in cement production workers. European Respiratory Journal. ISSN 0903-1936. 38(6), p. 1278–1286. doi: 10.1183/09031936.00007711. Full text in Research Archive Show summary

  Cement dust exposure has previously been associated with airway symptoms and ventilatory impairment. The aim of the present study was to examine lung function and airway symptoms among employees in different jobs and at different levels of exposure to thoracic dust in the cement production industry. At the start of a 4-yr prospective cohort study in 2007, exposure to cement dust, symptoms and lung function were recorded cross-sectionally in 4,265 employees in 24 European cement plants. Bronchial exposure was assessed by 2,670 full-shift dust samples with cyclones collecting the thoracic aerosol fraction. A job exposure matrix was constructed by grouping dust concentrations according to job type and plant. Elevated odds ratios for symptoms and airflow limitation (range 1.2–2.6 in the highest quartile), but not for chronic bronchitis, were found in the higher quartiles of exposure compared with the lowest quartile. Forced expiratory volume in 1 s (FEV1) showed an exposure–response relationship with a 270-mL deficit of FEV1 (95% CI 190–300 mL) in the highest compared with the lowest exposure level. The results support the hypothesis that exposure to dust in cement production may lead to respiratory symptoms and airway obstruction.

• Fell, Anne Kristin Møller; Notø, Hilde Pettersen; Skogstad, Marit; Nordby, Karl-Christian; Wijnand, Eduard & Svendsen, Martin Veel [Show all 9 contributors for this article] (2011). A cross-shift study of lung function, exhaled nitric oxide and inflammatory markers in blood in Norwegian cement production workers. Occupational and Environmental Medicine. ISSN 1351-0711. 68(11), p. 799–805. doi: 10.1136/oem.2010.057729. Full text in Research Archive Show summary

  Objectives To study possible effects of aerosol exposure on lung function, fractional exhaled nitric oxide (FeNO) and inflammatory markers in blood from Norwegian cement production workers across one work shift (0 to 8 h) and again 32 h after the non-exposed baseline registration. Methods 95 workers from two cement plants in Norway were included. Assessment of lung function included spirometry and gas diffusion pre- and post-shift (0 and 8 h). FeNO concentrations were measured and blood samples collected at 0, 8 and 32 h. Blood analysis included cell counts of leucocytes and mediators of inflammation. Results The median respirable aerosol level was 0.3 mg/m3 (range 0.02–6.2 mg/m3). FEV1, FEF25–75% and DLCO decreased by 37 ml (p=0.04), 170 ml/s (p<0.001) and 0.17 mmol/min/kPa (p=0.02), respectively, across the shift. A 2 ppm reduction in FeNO between 0 and 32 h was detected (p=0.01). The number of leucocytes increased by 0.6×109 cells/l (p<0.001) across the shift, while fibrinogen levels increased by 0.02 g/l (p<0.001) from 0 to 32 h. TNF-α level increased and IL-10 decreased across the shift. Baseline levels of fibrinogen were associated with the highest level of respirable dust, and increased by 0.39 g/l (95% CI 0.06 to 0.72). Conclusions We observed small cross-shift changes in lung function and inflammatory markers among cement production workers, indicating that inflammatory effects may occur at exposure levels well below 1 mg/m3. However, because the associations between these acute changes and personal exposure measurements were weak and as the long-term consequences are unknown, these findings should be tested in a follow-up study.

• Fell, Anne Kristin Møller; Sikkeland, Liv Ingunn Bjoner; Svendsen, Martin Veel & Kongerud, Johny (2010). Airway inflammation in cement production workers. Occupational and Environmental Medicine. ISSN 1351-0711. 67(6), p. 395–400. doi: 10.1136/oem.2009.047852. Full text in Research Archive
• Fell, Anne Kristin Møller; Sikkeland, Liv Ingunn Bjoner; Svendsen, MV & Kongerud, Johny (2009). Airway Inflammation in Cement Production Workers. Occupational and Environmental Medicine. ISSN 1351-0711. doi: 10.1136/oem.2009.047852. Full text in Research Archive
• Fell, Anne Kristin M.; Thomassen, Thomas R.; Kristensen, Petter; Egeland, Thore & Kongerud, Johny (2003). Respiratory symptoms and ventilatory function in workers exposed to portland cement dust. Journal of Occupational and Environmental Medicine. ISSN 1076-2752. 45(9), p. 1008–1014. doi: 10.1097/01.jom.0000083036.56116.9d. Full text in Research Archive Show summary

  The healthy worker effect and incomplete exposure information have been problems in former studies regarding the association between exposure to Portland cement dust and respiratory effects. We included former workers and made an individual estimation of particle exposure to reduce the selection bias in this controlled cross-sectional study on the effects of cement dust exposure on respiratory symptoms and ventilatory function in long-term exposed Norwegian cement plant workers. A total of 119 workers from the largest cement plant in Norway and 50 workers from a nearby control plant, born 1918 to 1938, performed spirometry and gave information on respiratory symptoms in 1998 and 1999. The prevalence of symptoms and mean pulmonary function indices were similar for exposed workers and controls. There was no dose-response-related increase in symptoms or decrease in lung function indices. The estimated power to detect a true difference between forced expiratory volume in one second (FEV1) in the two groups of 0.3l was 0.90, assuming 95% significance level. The prevalence of chronic obstructive pulmonary disease was 14.3% in the exposed group and 14.0% among the controls. These findings do not support the hypothesis that cement dust exposure has a negative impact on lung function or gives an increase in respiratory symptoms.

View all works in NVA

• Oellingrath, Inger Margaret; Bortoli, Marit Müller De; Svendsen, Martin Veel & Fell, Anne Kristin Møller (2019). Lifestyle risk index, work ability and sick leave among Norwegian employees with and without physician-diagnosed asthma. Full text in Research Archive
• Bortoli, Marit Müller De; Oellingrath, Inger Margaret; Svendsen, Martin Veel & Fell, Anne Kristin Møller (2018). Lifestyle and work ability in a Norwegian general working population. Full text in Research Archive
• Fell, Anne Kristin Møller; Kim, Jeong-Lim; Abrahamsen, Regine; Svendsen, Martin Veel; Torén, Kjell & Henneberger, Paul K [Show all 7 contributors for this article] (2016). Household smoking and respiratory health in Telemark, Norway - 10 years after the introduction of a smoking ban. European Respiratory Journal. ISSN 0903-1936. Full text in Research Archive
• Abrahamsen, Regine; Fell, Anne Kristin Møller; Svendsen, Martin Veel; Andersson, Eva; Torén, Kjell & Henneberger, Paul K [Show all 7 contributors for this article] (2016). Occupational groups associated with asthma related respiratory symptoms in a cross-sectional study from Norway. Full text in Research Archive
• Fell, Anne Kristin Møller; Kim, Jeong-Lim; Abrahamsen, Regine; Svendsen, Martin Veel; Torén, Kjell & Henneberger, Paul K [Show all 7 contributors for this article] (2016). Household smoking and respiratory health in Telemark, Norway - 10 years after the introduction of a smoking ban. Full text in Research Archive
• Abrahamsen, Regine; Svendsen, Martin Veel; Henneberger, Paul K; Torén, Kjell; Kongerud, Johny & Fell, Anne Kristin Møller (2016). Exposure to damp and mould at home in relation to respiratory symptoms in the Telemark study, Norway. European Respiratory Journal. ISSN 0903-1936. Full text in Research Archive
• Fell, Anne Kristin Møller; Eikeland, Randi & Aaseth, Jan (2016). A woman in her thirties with cough, tremor, agitation and visual disturbances. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 14(136), p. 1233–1235. doi: 10.4045/tidsskr.15.0998. Full text in Research Archive
• Abrahamsen, Regine; Svendsen, Martin Veel; Henneberger, Paul K; Torén, Kjell; Kongerud, Johny & Fell, Anne Kristin Møller (2016). Exposure to damp and mould at home in relation to respiratory symptoms in the Telemark study, Norway. Full text in Research Archive
• Abrahamsen, Regine; Fell, Anne Kristin Møller; Svendsen, Martin Veel; Andersson, Eva; Torén, Kjell & Henneberger, Paul K [Show all 7 contributors for this article] (2016). Occupational groups associated with asthma related respiratory symptoms in a cross-sectional study from Norway. European Respiratory Journal. ISSN 0903-1936. Full text in Research Archive
• Svendsen, Martin Veel & Fell, Anne Kristin Møller (2016). Lungehelse i Telemark(Telemarkstudien). Ramazzini: norsk tidsskrift for arbeids- og miljømedisin. ISSN 0805-5238. 23(4), p. 18–20. Full text in Research Archive
• Abrahamsen, Regine; Svendsen, Martin Veel; Henneberger, Paul K; Gundersen, Gølin Finkenhagen; Torén, Kjell & Kongerud, Johny [Show all 7 contributors for this article] (2015). Non-response in a population-based study of respiratory health in Norway. Full text in Research Archive
• Abrahamsen, Regine; Svendsen, Martin Veel; Henneberger, Paul K; Gundersen, Gølin Finkenhagen; Torén, Kjell & Kongerud, Johny [Show all 7 contributors for this article] (2015). Non-response in a population-based study of respiratory health in Norway. European Respiratory Journal. ISSN 0903-1936. Full text in Research Archive
• Fell, Anne Kristin Møller; Abrahamsen, Regine; Henneberger, Paul K; Svendsen, Martin Veel; Torén, Kjell & Kongerud, Johny (2015). Late braking abstract: Breath-taking jobs: Respiratory work disability by occupation. ERS Poster discussion. European Respiratory Journal. ISSN 0903-1936. Full text in Research Archive
• Fell, Anne Kristin Møller; Abrahamsen, Regine; Henneberger, Paul K; Svendsen, Martin Veel; Torén, Kjell & Kongerud, Johny (2015). Late braking abstract: Breath-taking jobs: Respiratory work disability by occupation. ERS Poster discussion. Full text in Research Archive
• Fell, Anne Kristin Møller; Abrahamsen, Regine; Svendsen, Martin Veel; Torén, Kjell; Henneberger, Paul K & Kongerud, Johny (2014). Respiratory symptoms and change of workplace in the general population of Telemark. Full text in Research Archive
• Fell, Anne Kristin Møller (2014). Increased prevalance of astma Associated With accidental peak exposures. Full text in Research Archive
• Fell, Anne Kristin Møller; Sikkeland, Liv Ingunn Bjoner & Kongerud, Johny (2008). Airway Inflammation among Portland Cement Workers. Full text in Research Archive

View all works in NVA