Morten Ingvar Lossius

• Kostov, Konstantin Hrisimirov; Kostov, Hrisimir; Larsson, Pål Gunnar; Henning, Oliver Johannes; Aaberg, Kari Modalsli & Egge, Arild [Show all 8 contributors for this article] (2024). Norwegian population-based study of effectiveness of vagus nerve stimulation in patients with developmental and epileptic encephalopathies. Epilepsia Open. ISSN 2470-9239. doi: 10.1002/epi4.12908.
• Hlauschek, Gernot; Nicolo, John-Paul; Sinclair, Benjamin; Law, Meng; Yasuda, Clarissa L. & Cendes, Fernando [Show all 9 contributors for this article] (2023). Role of the glymphatic system and perivascular spaces as a potential biomarker for post-stroke epilepsy. Epilepsia Open. ISSN 2470-9239. p. 1–17. doi: 10.1002/epi4.12877. Full text in Research Archive
• Terman, Samuel W.; Slinger, Geertruida; Koek, Adriana; Skvarce, Jeremy; Springer, Mellanie V. & Ziobro, Julie M. [Show all 13 contributors for this article] (2023). Variation in seizure risk increases from antiseizure medication withdrawal among patients with well-controlled epilepsy: A pooled analysis. Epilepsia Open. ISSN 2470-9239. p. 333–334. doi: 10.1002/epi4.12880. Full text in Research Archive
• Hlauschek, Gernot; Lossius, Morten Ingvar; Schwartz, Daniel L; Silbert, Lisa C; Hicks, Amelia J & Ponsford, Jennie L [Show all 13 contributors for this article] (2023). Reduced total number of enlarged perivascular spaces in post-traumatic epilepsy patients with unilateral lesions – a feasibility study. Seizure. ISSN 1059-1311. 113, p. 1–5. doi: 10.1016/j.seizure.2023.10.006. Full text in Research Archive
• Villagran, Antonia; Lund, Caroline; Duncan, Roderick & Lossius, Morten Ingvar (2023). Adverse life events in patients with functional seizures: Assessment in clinical practice and association with long-term outcome. Epilepsy & Behavior. ISSN 1525-5050. 148, p. 1–7. doi: 10.1016/j.yebeh.2023.109456. Full text in Research Archive
• Hauger, Lisa Evju; Lossius, Morten Ingvar; Aaberg, Kari Modalsli; Helmstaedter, Christoph; Lossius, Johanne & Skogan, Annette Holth (2023). Screening of attention and executive functions in pediatric patients at a tertiary epilepsy center. European journal of paediatric neurology. ISSN 1090-3798. 46, p. 35–41. doi: 10.1016/j.ejpn.2023.06.006.
• Kloster, Ane G.; Opheim, Giske; Alfstad, Kristin Åshild; Larsen, Karen B.; Niehusmann, Pitt & Holm, Emil [Show all 16 contributors for this article] (2023). Postprocessing of MRIs Using FreeSurfer in Epilepsy Surgery Patients Provides an Excellent Imaging Marker of Hippocampal Sclerosis but Fails to Separate Subtypes. Acta Neurologica Scandinavica. ISSN 0001-6314. 2023, p. 1–10. doi: 10.1155/2023/2366355. Full text in Research Archive
• Kverneland, Magnhild; Nakken, Karl Otto; Hofoss, Dag; Skogan, Annette Holth; Iversen, Per Ole & Selmer, Kaja Kristine [Show all 7 contributors for this article] (2023). Health-related quality of life in adults with drug-resistant focal epilepsy treated with modified Atkins diet in a randomized clinical trial. Epilepsia. ISSN 0013-9580. 64(5). doi: 10.1111/epi.17585. Full text in Research Archive
• Villagran, Antonia; Lund, Caroline; Duncan, Roderick & Lossius, Morten Ingvar (2022). The effect of attachment style on long-term outcomes in psychogenic nonepileptic seizures: Results from a prospective study. Epilepsy & Behavior. ISSN 1525-5050. 135, p. 1–6. doi: 10.1016/j.yebeh.2022.108890. Full text in Research Archive
• Henning, Oliver Johannes; Alfstad, Kristin Åshild; Landmark, Cecilie Johannessen; Helmstadter, Cristoph; Lossius, Morten Ingvar & Skogan, Annette Holth (2022). Use of screening tools to assess comorbidities and adverse events in patients with epilepsy. A European Reference Network for Rare and Complex Epilepsies (EpiCARE) survey. Seizure. ISSN 1059-1311. 101, p. 237–243. doi: 10.1016/j.seizure.2022.09.008.
• Terman, Samuel W.; Wang, Chang; Wang, Lu; Braun, Kees P. J.; Otte, Willem M. & Slinger, Geertruida [Show all 11 contributors for this article] (2022). Reappraisal of the Medical Research Council Antiepileptic Drug Withdrawal Study: Contamination-adjusted and dose-response re-analysis. Epilepsia. ISSN 0013-9580. 63(7), p. 1724–1735. doi: 10.1111/epi.17273. Full text in Research Archive
• Svendsen, Torleiv; Brodtkorb, Eylert; Linge, Hanna Lande; Burns, Margrete Larsen; Johannessen, Svein Ivar & Nakken, Karl Otto [Show all 8 contributors for this article] (2022). Efficacy, tolerability and pharmacokinetic variability of brivaracetam in adults with difficult-to-treat epilepsy. Epilepsy Research. ISSN 0920-1211. 183, p. 1–6. doi: 10.1016/j.eplepsyres.2022.106946. Show summary

  Purpose: Brivaracetam (BRV) is one of our latest antiseizure medications (ASMs). It is an analogue of levetiracetam with limited real-life experience. The purpose of this study was to evaluate clinical experience with BRV with focus on efficacy, tolerability and pharmacokinetic variability among adult patients with difficult-to-treat epilepsy. Methods: We retrospectively collected clinical and laboratory data from patients aged > 18 years who initiated treatment with BRV during 2016-2019 and were followed for > one year or cessation of BRV. Results: The study cohort consisted of 120 adults with drug-resistant epilepsy. Serum concentrations of BRV were available in 72 patients. After one-year follow-up, the retention rate of BRV was 52%. Fifty-seven patients (48%) were responders (>50 reduction of seizure frequency), of whom six became seizure free. Adverse effects were reported in 78 patients (65%); 37 (31%) experienced psychiatric problems like increased irritability, anxiety and depressive symptoms. The mean daily BRV dose was 159 mg (SD 80 mg) and the mean serum concentration 5.4 μmol/L (SD 4.1 μmol/L). In 24 patients, BRV replaced levetiracetam. Pharmacokinetic variability between patients was considerable; 14-fold variation in concentration/dose (C/D)-ratios. Concomitant use of enzyme-inducing ASMs decreased the C/D-ratio by 48%. There were no significant differences in serum concentrations between responders vs. non-responders, or those who experienced adverse effects or not. Conclusion: After > 1 year of treatment with BRV, we found a responder rate of 48% in adult patients with difficult-to-treat epilepsy. The drug was largely well tolerated, but one third experienced psychiatric adverse effects. The combination of clinical and pharmacokinetic data provides insight into factors contributing to efficacy and tolerability of new ASMs. Keywords: Antiseizure medications; Efficacy; Epilepsy; Therapeutic drug monitoring; Tolerability. Copyright © 2022 Elsevier B.V. All rights reserved.

• Sabers, Anne; Aumüller-Wagner, Sophia; Christensen, Lars Rune; Henning, Oliver Johannes; Kostov, Konstantin Hrisimirov & Lossius, Morten Ingvar [Show all 11 contributors for this article] (2021). Feasibility of transcutaneous auricular vagus nerve stimulation in treatment of drug resistant epilepsy: A multicenter prospective study. Epilepsy Research. ISSN 0920-1211. 177. doi: 10.1016/j.eplepsyres.2021.106776.
• Kostov, Konstantin Hrisimirov; Kostov, Hrisimir; Larsson, Pål Gunnar; Henning, Oliver Johannes; Eckmann, Christian Alexander Cornelius & Lossius, Morten Ingvar [Show all 7 contributors for this article] (2021). Norwegian population-based study of long-term effects, safety, and predictors of response of vagus nerve stimulation treatment in drug-resistant epilepsy: The NORPulse study. Epilepsia. ISSN 0013-9580. doi: 10.1111/epi.17152. Full text in Research Archive
• Heminghyt, Einar; Herrman, Helle; Skogan, Annette Holth; Konglund, Ane; Egge, Arild & Lossius, Morten Ingvar [Show all 8 contributors for this article] (2021). Cognitive change after DBS in refractory epilepsy: A randomized-controlled trial. Acta Neurologica Scandinavica. ISSN 0001-6314. p. 1–8. doi: 10.1111/ane.13539. Full text in Research Archive
• Henning, Oliver Johannes; Buer, Charlotte; Nakken, Karl Otto & Lossius, Morten I. (2021). People with epilepsy still feel stigmatized. Acta Neurologica Scandinavica. ISSN 0001-6314. 144(3), p. 312–316. doi: 10.1111/ane.13449. Full text in Research Archive
• Villagran, Antonia; Eldøen, Guttorm; Duncan, Roderick; Aaberg, Kari Modalsli; Hofoss, Dag & Lossius, Morten (2021). Incidence and prevalence of psychogenic nonepileptic seizures in a Norwegian county: A 10-year population-based study. Epilepsia. ISSN 0013-9580. 62(7), p. 1528–1535. doi: 10.1111/epi.16949. Full text in Research Archive Show summary

  Objective: This study was undertaken to measure the incidence and prevalence of active psychogenic nonepileptic seizures (PNES) in a Norwegian county.Methods: Using the Norwegian patient registry, we identified patients in Møre and Romsdal County in Norway diagnosed with F44.5 (conversion disorder with seizures or convulsions) or R56.8 (convulsions, not elsewhere classified) in the period January 2010 to January 2020. A review of the patients' medical records and an assessment of diagnostic validity were performed. PNES were diagnosed according to the rec-ommendations by the International League Against Epilepsy Nonepileptic Seizures Task Force. Point prevalence of PNES on January 1, 2020 and incidence rates for the period 2010– 2019 were determined.Results: Based on PNES within the past 5 years, we found a PNES prevalence of 23.8/100 000 (95% confidence interval [CI] = 17.9– 29.6), including all lev-els of diagnostic certainty. For the highest level of diagnostic certainty (video- electroencephalographically confirmed), the prevalence was 10.6/100 000 (95% CI = 6.7– 14.5). The highest prevalence was found in the age group 15– 19 years, at 59.5/100 000 (95% CI = 22.6– 96.3). The mean annual incidence rate between 2010 and 2019 was 3.1/100 000/year (95% CI = 2.4– 3.7).Significance: We report for the first time a population- based estimate of the preva-lence of PNES. Our findings suggest that the prevalence of PNES is within the range of estimates from non- population- based data. We found a strikingly high prevalence of PNES in the 15– 19- year age group.KEYWORDSadolescents, diagnostic coding, epidemiology, psychogenic nonepileptic seizures

• Lossius, Ida Marie Bakke; Svendsen, Torleiv; Sødal, Hild Flatmark; Kjeldstadli, Kari Grandaunet; Lossius, Morten Ingvar & Nakken, Karl Otto [Show all 7 contributors for this article] (2021). Effect and tolerability of perampanel in patients with drug-resistant epilepsy. Epilepsy & Behavior. ISSN 1525-5050. 119. doi: 10.1016/j.yebeh.2021.107965. Full text in Research Archive Show summary

  Objective: Perampanel is one of the most recently approved antiseizure medications. The aim of the present study was to assess clinical efficacy and tolerability, in combination with pharmacokinetic variability, of perampanel treatment in patients at a tertiary referral center for epilepsy. Methods: We performed a retrospective observational study of patients given perampanel as adjunctive treatment in the period January 2013 - February 2019 at the National Center for Epilepsy at Oslo University Hospital, Norway. Results: Clinical data were available for 175 mainly adult patients with drug-resistant epilepsy with mean treatment duration of 16.1 months. We found that 23% (40 patients) were responders (i.e., achieving more than 50% reduction in seizure frequency), four of whom became seizure free, 29% (51 patients) experienced a modest effect, whereas for 29% (50 patients) perampanel had no seizure-reducing effect. A paradoxical effect, with seizure aggravation, was reported in 9% (15 patients). The responder rate was significantly higher in those with slow vs. fast dosage titration. Logistic regression analysis showed better efficacy among those with generalized vs. those with focal epilepsy. Adverse effects were reported by 135 patients (77%), ranging from mild (34%), to moderate (41%) and severe (2%). In 55 patients (41%), these adverse effects resulted in discontinuation of treatment with perampanel. The most frequent adverse effects were psychiatric symptoms (34%), dizziness (31%), and sleepiness (26%). Of the 31 patients for whom serum concentration measurements were available, the mean daily perampanel dose was 6.3 mg (SD 3.0), with a mean serum concentration at steady state of 1.03 μmol/L (range: 0.15-3.59 μmol/L). There were pronounced differences between patients, as demonstrated by a 12-fold variability in the range of concentration/dose (C/D)-ratios (0.06 to 0.69 μmol/L/mg), where enzyme inducers contributed. Conclusion: Our results demonstrate that perampanel had a modest seizure-reducing effect in this very treatment-resistant patient group. Predictors of treatment success were generalized epilepsy and slow dosage titration. In patients without a history of psychiatric problems, clinicians could consider increasing dose of perampanel beyond 6 mg daily, taking co-medication and serum concentrations into account. Keywords: Antiseizure medications drugs; Serum concentrations; Therapeutic drug monitoring. Copyright © 2021 Elsevier Inc. All rights reserved.

• Markuola, Sofia; Limpias, Andreas; Rubboli, Guido; Duncan, John; Velis, Demetrios & Schultze-Bonhage, Andreas [Show all 33 contributors for this article] (2020). A European Questionnaire survey on epilepsy monitoring units`current practice for postoperative psychogenic nonepileptic seizures`detection. Epilepsy & Behavior. ISSN 1525-5050. 112. doi: 10.1016/j.yebeh.2020.107355.
• Markhus, Rune; Henning, Oliver Johannes; Molteberg, Ellen; Hecimovic, Hrvoje; Ujvari, akos & hirsch, edouard [Show all 30 contributors for this article] (2020). EEG in fitness to drive evaluations in people with epilepsy-Considerable variations across Europe. Seizure. ISSN 1059-1311. 79. doi: 10.1016/j.seizure.2020.04.013.
• Zaidan, Sabreen; Nakken, Karl Otto; Lillestølen, Kari Mette; Alvestad, Silje & Lossius, Morten (2020). Assisted reproductive treatment in women with epilepsy. Tidsskrift for Den norske legeforening. ISSN 0029-2001. doi: 10.4045/tidsskr.19.0253.
• Henning, Oliver Johannes; Medalen, Tone Eline; Nakken, Karl Otto & Lossius, Morten (2020). How often do doctors discuss drug withdrawal with their seizure-free patients with epilepsy? Epilepsy & Behavior. ISSN 1525-5050. 108, p. 1–3. doi: 10.1016/j.yebeh.2020.107095. Full text in Research Archive
• Svendsen, Torleiv; Brodtkorb, Eylert; Baftiu, Arton; Lossius, Morten; Nakken, Karl Otto & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2019). Clinical experience combined with therapeutic drug monitoring of lacosamide. Acta Neurologica Scandinavica. ISSN 0001-6314. 00, p. 1–8. doi: 10.1111/ane.13206. Full text in Research Archive Show summary

  Objective: Lacosamide (LCM) is an antiepileptic drug (AED) with insufficient clinical experience in patients with intellectual disability (ID). They often have more severe epilepsy with comorbidities. The objective was to evaluate the efficacy and tolerabil-ity of lacosamide (LCM) in patients with refractory epilepsy with and without ID in a real-life setting, taking drug monitoring (TDM) data into account therapeutic.Methods: Retrospectively, we identified 344 patients using LCM from the TDM service covering the majority of the country, at the National Center for Epilepsy in Norway (2013-2018). Clinical and TDM data were available for 132 patients.Results: Forty-four of the 132 patients (33%) had ID. The retention rate was signifi-cantly higher in the ID vs the non-ID group after 1 year (84% vs 68%, P < .05). By combining clinical and TDM data, we demonstrated that 37/38 responding patients had serum concentrations above the lower limit of the reference range (>10 μmol/L), and 16/17 with lower concentrations were non-responders. Mean serum concentra-tion/dose ratios were similar in both groups, 0.06 and 0.07 μmol/L/mg. There were no significant differences regarding efficacy and tolerability. The risk of LCM with-drawal was significantly higher when LCM was added to sodium channel blockers, even if the latter was discontinued.Significance: Lacosamide was generally well tolerated in patients with drug-resistant epilepsy, where one third had ID, and in these patients the retention rate was higher. The combination of clinical and TDM data could possibly facilitate LCM therapy in these vulnerable patients.

• Henning, Oliver Johannes; Lossius, Morten; Lima, Maren Haugen; Mevåg, Morten Andreas; Villagran, Antonia & Nakken, Karl Otto [Show all 7 contributors for this article] (2019). Refractory epilepsy and nonadherence to drug treatment. Epilepsia Open. ISSN 2470-9239. 4(4), p. 618–623. doi: 10.1002/epi4.12367. Full text in Research Archive
• Henning, Oliver Johannes; Landmark, Cecilie Johannessen; Træen, Bente; Svendsen, Torleiv; Farmen, Anette Huuse & Nakken, Karl Otto [Show all 7 contributors for this article] (2019). Sexual function in people with epilepsy: Similarities and differences with the general population. Epilepsia. ISSN 0013-9580. 60(9), p. 1984–1992. doi: 10.1111/epi.16311. Full text in Research Archive Show summary

  OBJECTIVE: The potential impact of epilepsy on sexual function is important for patient welfare, but often neglected. This study explored the occurrences of different sexual problems in patients with both well-controlled and mostly refractory epilepsy, and compared these with equivalent information from the general population. METHODS: Between 2015 and 2017, a total of 221 adult inpatients and outpatients, mostly with intractable epilepsy, at the National Centre for Epilepsy in Norway, and 78 outpatients with well-controlled epilepsy at Lillehammer hospital participated in a questionnaire survey on sexual function. Information on the individual patient's epilepsy was collected. The results were compared with equivalent data on sexual function from 1671 adult Norwegians in the general population. RESULTS: Patients with epilepsy reported a significantly higher frequency of problems with orgasm, dyspareunia, erectile dysfunction, and feelings of sexual deviance. However, reduced sexual desire, premature ejaculation/climax, and vaginal dryness occurred at similar frequencies in the general population. After controlling for gender, we found no significant association between sexual problems and seizure control or use of enzyme-inducing antiepileptic drugs. In both genders, feelings of sexual deviance were associated with lower quality of life. Fewer patients with epilepsy were satisfied with their sex lives. The perception of sex as an important part of daily life was similar among women with epilepsy and women from the general population, whereas significantly fewer men with epilepsy than men in the general population reported that sex was an important part of their daily lives. Women with mostly refractory epilepsy reported asking for help with their sexual problems significantly more often than women in the other groups. SIGNIFICANCE: Some sexual problems occur significantly more often in patients with epilepsy than in the general population and feelings of sexual deviancy occur more frequently. No epilepsy-related factors could be identified as specific predictors. © 2019 The Authors. Epilepsia published by Wiley Periodicals, Inc. on behalf of International League Against Epilepsy. KEYWORDS: comorbidity; epilepsy; quality of life; sexual dysfunction; sexual problems

• Henning, Oliver Johannes; Alfstad, Kristin Åshild; Nakken, Karl Otto & Lossius, Morten (2019). A call for better information about epilepsy: The patients? perspective?An online survey. Seizure. ISSN 1059-1311. 69, p. 173–179. doi: 10.1016/j.seizure.2019.04.015.
• Henning, Oliver Johannes; Landmark, Cecilie Johannessen; Nakken, Karl Otto & Lossius, Morten (2019). Nonadherence to treatment regimens in epilepsy from the patient's perspective and predisposing factors: Differences between intentional and unintentional lack of adherence. Epilepsia. ISSN 0013-9580. 60(5), p. e58–e62. doi: 10.1111/epi.14734.
• Henning, Oliver Johannes; Landmark, Cecilie Johannessen; Henning, David; Nakken, Karl Otto & Lossius, Morten (2019). Challenges in epilepsy – the perspective of Norwegian epilepsy patients. Acta Neurologica Scandinavica. ISSN 0001-6314. 140(1), p. 40–47. doi: 10.1111/ane.13098. Full text in Research Archive
• Baud, Maxime O.; Perneger, Thomas; Rácz, Attila; Pensel, Max C.; Elger, Christian E. & Rydenhag, Bertil [Show all 40 contributors for this article] (2018). European trends in epilepsy surgery. Neurology. ISSN 0028-3878. 91(2), p. e96–e106. doi: 10.1212/WNL.0000000000005776.
• Henning, Oliver Johannes; Nakken, Karl Otto & Lossius, Morten (2018). People with epilepsy and their relatives want more information about risks of injuries and premature death . Epilepsy & Behavior. ISSN 1525-5050. 82, p. 6–10. doi: 10.1016/j.yebeh.2018.02.023.
• Farmen, Anette Huuse; Grundt, Jacob Holter; Nakling, Ole Jakob; Mowinckel, Petter; Nakken, Karl Otto & Lossius, Morten (2018). Increased rate of acute caesarean sections in women with epilepsy: results from the Oppland Perinatal Database in Norway. European Journal of Neurology. ISSN 1351-5101. p. 1–7. doi: 10.1111/ene.13865. Full text in Research Archive
• Hessen, Erik; Alfstad, Kristin Åshild; Torgersen, Halvor & Lossius, Morten (2018). Tested and reported executive problems in children and youth epilepsy. Brain and Behavior. ISSN 2162-3279. 8(5). doi: 10.1002/brb3.971. Full text in Research Archive
• Aaberg, Kari Modalsli; Bakken, Inger Johanne; Lossius, Morten; Søraas, Camilla Lund; Tallur, Kamath K. & Stoltenberg, Camilla [Show all 8 contributors for this article] (2018). Short-term seizure outcomes in childhood epilepsy. Pediatrics. ISSN 0031-4005. 141(6). doi: 10.1542/peds.2017-4016.
• Landmark, Cecilie Johannessen; Farmen, Anette Huuse; Burns, Margrete Larsen; Baftiu, Arton; Lossius, Morten & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2018). Pharmacokinetic variability of valproate in pregnancy-implications for the use of therapeutic drug monitoring. Epilepsy Research. ISSN 0920-1211. 141, p. 31–37. doi: 10.1016/j.eplepsyres.2018.02.004.
• Vogt, Viola Lara; Äikiä, Marja; del Barrio, Antonio; Boon, Paul; Borbély, Csaba & Bran, Ema [Show all 56 contributors for this article] (2017). Current standards of neuropsychological assessment in epilepsy surgery centers across Europe. Epilepsia. ISSN 0013-9580. 58(3), p. 343–355. doi: 10.1111/epi.13646.
• Kolstad, Eivind; Bjørk, Marte Helene; Gilhus, Nils Erik; Alfstad, Kristin Åshild; Clench-Aas, Jocelyne & Lossius, Morten (2017). Young people with epilepsy have an increased risk of eating disorder and poor quality diet. Epilepsia Open. ISSN 2470-9239. 3(1), p. 40–45. doi: 10.1002/epi4.12089. Full text in Research Archive
• Aaberg, Kari Modalsli; Surén, Pål; Søraas, Camilla Lund; Bakken, Inger Johanne; Lossius, Morten & Stoltenberg, Camilla [Show all 7 contributors for this article] (2017). Seizures, syndromes, and etiologies in childhood epilepsy: The International League Against Epilepsy 1981, 1989, and 2017 classifications used in a population-based cohort. Epilepsia. ISSN 0013-9580. 58(11), p. 1880–1891. doi: 10.1111/epi.13913.
• Landmark, Cecilie Johannessen; Burns, Margrete Larsen; Baftiu, Arton; Farmen, Anette Huuse; Lossius, Morten & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2017). Pharmacokinetic variability of valproate in women of childbearing age. Epilepsia. ISSN 0013-9580. 58(10), p. 142–146. doi: 10.1111/epi.13872.
• Aaberg, Kari Modalsli; Gunnes, Nina; Bakken, Inger Johanne; Søraas, Camilla Lund; Berntsen, Alexander & Magnus, Per [Show all 10 contributors for this article] (2017). Incidence and prevalence of childhood epilepsy: A nationwide cohort study. Pediatrics. ISSN 0031-4005. 139(5). doi: 10.1542/peds.2016-3908. Show summary

  BACKGROUND AND OBJECTIVES: Epilepsy affects 0.5% to 1% of children and is the most frequent chronic neurologic condition in childhood. Incidence rates appear to be declining in high-income countries. The validity of epilepsy diagnoses from different data sources varies, and contemporary population-based incidence studies are needed. METHODS: The study was based on the Norwegian Mother and Child Cohort Study. Potential epilepsy cases were identified through registry linkages and parental questionnaires. Cases were validated through medical record reviews and telephone interviews of parents. RESULTS: The study population included 112 744 children aged 3 to 13 years (mean 7.4 years) at end of registry follow-up (December 31, 2012). Of these, 896 had registry recordings and/or questionnaire reports of epilepsy. After validation, 587 (66%) met the criteria for an epilepsy diagnosis. The incidence rate of epilepsy was 144 per 100 000 person-years in the first year of life and 58 per 100 000 for ages 1 to 10 years. The cumulative incidence of epilepsy was 0.66% at age 10 years, with 0.62% having active epilepsy. The 309 children (34%) with erroneous reports of epilepsy from the registry and/or the questionnaires had mostly been evaluated for nonepileptic paroxysmal events, or they had undergone electroencephalography examinations because of other developmental or neurocognitive difficulties. CONCLUSIONS: Approximately 1 out of 150 children is diagnosed with epilepsy during the first 10 years of life, with the highest incidence rate observed during infancy. Validation of epilepsy diagnoses in administrative data and cohort studies is crucial because reported diagnoses may not meet diagnostic criteria for epilepsy.

• Lossius, Morten Ingvar; Villagran, Antonia; Karterud, Hilde; Henning, Oliver Johannes & Nakken, Karl Otto (2016). Psykogene ikke-epileptiske anfall hos barn. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 136(23-24), p. 1993–1995. doi: 10.4045/tidsskr.16.0312.
• Svendsen, Torleiv; Alfstad, Kristin Åshild; Lossius, Morten Ingvar & Nakken, Karl Otto (2016). Langtidsbivirkninger av antiepileptika. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 136(4), p. 324–327. doi: 10.4045/tidsskr.15.0220.
• Kobulashvili, Teia; Höfler, Julia; Dobesberger, Judith; Ernst, Florian; Ryvlin, Philippe & Cross, J Helen [Show all 31 contributors for this article] (2016). Current practices in long-term video-EEG monitoring services: A survey among partners of the E-PILEPSY pilot network of reference for refractory epilepsy and epilepsy surgery. Seizure. ISSN 1059-1311. 38, p. 38–45. doi: 10.1016/j.seizure.2016.03.009.
• Mouthaan, Brian E; Rados, Matea; Barsi, Peter; Boon, Paul; Carmichael, David W & Carrette, Evelien [Show all 55 contributors for this article] (2016). Current use of imaging and electromagnetic source localization procedures in epilepsy surgery centers across Europe. Epilepsia. ISSN 0013-9580. 57(5), p. 770–776. doi: 10.1111/epi.13347.
• Lossius, Morten; Nakken, Karl Otto; Mowinckel, Petter; Taubøll, Erik & Gjerstad, Leif (2016). Favorable change of lipid profile after carbamazepine withdrawal. Acta Neurologica Scandinavica. ISSN 0001-6314. 134(3), p. 219–223. doi: 10.1111/ane.12534. Show summary

  Objective Patients treated with carbamazepine (CBZ) have increased serum levels of total cholesterol (TC), high-density lipoproteins (HDL), and low-density lipoproteins (LDL). We aimed to investigate whether these changes of serum lipids are reversible after CBZ withdrawal. Material and methods We used a prospective, randomized double-blinded design. A total of 160 patients who had been seizure free on anti-epileptic drug monotherapy for more than 2 years were included and randomized to withdrawal or not. The intervention was completed by 150 (80 females, 53%) patients. Serum samples from before and 4 months after completed withdrawal or no withdrawal were obtained from 130 patients (63 females, 48%). Of these, 84 were treated with CBZ, 28 with valproate, nine with phenytoin, four with phenobarbital, and five with lamotrigine. Of the patients who had been treated with CBZ, 47 were randomized to the withdrawal group, and 37 were randomized to the non-withdrawal group. Results Among the CBZ-treated patients, a significant decrease in serum levels of TC, LDL, and apolipoprotein B (ApoB) were found in the withdrawal group compared with the non-withdrawal group. Mean differences in change were as follows: TC 0.68 mmol/l (P = 0.005, CL – 1.15 to −0.21); LDL – 0.67 mmol/l (P = 0.001, CL – 1.03 to −0.29); ApoB – 0.13 g/l (P = 0.02, CL – 0.23 to −0.03). No significant changes in HDL, apolipoprotein A, and C-reactive protein were detected. Conclusion Our results indicate that CBZ may have unfavorable effects on serum levels of TC, LDL, and ApoB. However, these changes seem to be reversible even after years of treatment.

• Aaberg, Kari Modalsli; Bakken, Inger Johanne; Lossius, Morten; Søraas, Camilla Lund; Håberg, Siri Eldevik & Stoltenberg, Camilla [Show all 8 contributors for this article] (2016). Comorbidity and Childhood Epilepsy: A Nationwide Registry Study. Pediatrics. ISSN 0031-4005. 138(3). doi: 10.1542/peds.2016-0921. Full text in Research Archive
• Aurlien, Dag; Rath-Olsen, Trude; Taubøll, Erik; Gjerstad, Leif; Lossius, Morten & Nakken, Karl Otto (2016). Plutselig, uventet epilepsirelatert død. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 136(2), p. 131–135. doi: 10.4045/tidsskr.14.0640.
• Hansen, Berit Marina Hjelde; Alfstad, Kristin Åshild; Van Roy, Betty; Henning, Oliver Johannes & Lossius, Morten (2016). Sleep problems in children and adolescents with epilepsy: Associations with psychiatric comorbidity. Epilepsy & Behavior. ISSN 1525-5050. 62, p. 14–19. doi: 10.1016/j.yebeh.2016.06.015.
• Henning, Oliver Johannes; Nakken, Karl Otto; Træen, Bente; Mowinckel, Petter & Lossius, Morten (2016). Sexual problems in people with refractory epilepsy. Epilepsy & Behavior. ISSN 1525-5050. 64, p. 174–179. doi: 10.1016/j.yebeh.2016.08.015.
• Lossius, Morten; Alfstad, Kristin Åshild; Van Roy, Betty; Mowinckel, Petter; Clench-Aas, Jocelyne & Gjerstad, Leif [Show all 7 contributors for this article] (2016). Early sexual debut in Norwegian youth with epilepsy: A population-based study. Epilepsy & Behavior. ISSN 1525-5050. 56, p. 1–4. doi: 10.1016/j.yebeh.2015.12.014.
• Farmen, Anette Huuse; Grundt, Jacob Holter; Tomson, Torbjørn; Nakken, Karl Otto; Nakling, Ole Jakob & Mowinckel, Petter [Show all 8 contributors for this article] (2016). Age-specific birth rates in women with epilepsy: a population-based study. Brain and Behavior. ISSN 2162-3279. 6(8). doi: 10.1002/brb3.492.
• Alfstad, Kristin Åshild; Torgersen, Halvor; Van Roy, Betty; Hessen, Erik; Hansen, Berit Marina Hjelde & Henning, Oliver Johannes [Show all 10 contributors for this article] (2016). Psychiatric comorbidity in children and youth with epilepsy: An association with executive dysfunction? Epilepsy & Behavior. ISSN 1525-5050. 56, p. 88–94. doi: 10.1016/j.yebeh.2016.01.007.
• Realfsen, Martha Seim; Bø, Siri M. Hylleraas; Lossius, Morten & Nakken, Karl Otto (2015). Førstegangs generalisert tonisk-klonisk krampeanfall. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 135(14), p. 1256–1258. doi: 10.4045/tidsskr.14.0654.
• Farmen, Anette Huuse; Grundt, Jacob Holter; Tomson, Torbjörn; Nakken, Karl Otto; Nakling, Ole Jakob & Mowinckel, Petter [Show all 7 contributors for this article] (2015). Intrauterine growth retardation in foetuses of women with epilepsy. Seizure. ISSN 1059-1311. 28, p. 76–80. doi: 10.1016/j.seizure.2015.02.026. Show summary

  Various factors may affect intrauterine foetal growth, amongst which conditions such as epilepsy and the use of anti-epileptic drugs (AED) may play a role. This study investigated intrauterine growth of foetuses in women with epilepsy, as compared with controls, and explored whether intrauterine growth was affected by prenatal exposure to AED. Method Data were obtained from prospectively registered data regarding pregnancy and prenatal and perinatal factors in women in Oppland County in Norway. The final analysis included information from 166 mothers with epilepsy and 287 children. The control group consisted of 40,553 pregnancies in women without epilepsy registered in the same database. Results There was a significantly higher risk of the ponderal index being below the 10th percentile and infants being small for gestational age (SGA) in the epilepsy group; exposure to AED increased the risk. The frequency of SGA and low ponderal index was highest in Lamotrigine exposed infants. In the AED group, head circumference was significantly smaller among Carbamazepine exposed. Conclusion Impaired intrauterine growth of foetuses in women with epilepsy was identified. The frequency of SGA and low ponderal index was highest in Lamotrigine exposed infants. The epilepsy group had a higher risk profile for having smaller babies, in being younger at age, lower in body weight and more frequent smokers. However despite these differences, the effects of epilepsy and AED exposure were significant. The ponderal index may be a useful supplement to more established measures assessing intrauterine growth in epilepsy.

• Kolstad, Eivind; Gilhus, Nils Erik; Veiby, Gyri; Reiter, Simone B. C. Frizell; Lossius, Morten & Bjørk, Marte Helene (2015). Epilepsy and eating disorders during pregnancy: Prevalence, complications and birth outcome. Seizure. ISSN 1059-1311. 28, p. 81–84. doi: 10.1016/j.seizure.2015.02.014.
• Nakken, Karl Otto; Sætre, Erik; Markhus, Rune & Lossius, Morten (2013). Epilepsi hos eldre. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 133(5), p. 528–531. doi: 10.4045/tidsskr.12.0781.
• Hessen, Erik; Lossius, Morten & Gjerstad, Leif (2013). Repeated neuropsychological assessment in well-controlled epilepsy. Acta Neurologica Scandinavica. ISSN 0001-6314. 127(1), p. 53–60. doi: 10.1111/j.1600-0404.2012.01682.x.
• Bremer, Anna; Lossius, Morten & Nakken, Karl Otto (2012). Dravet syndrome - considerable delay in making the diagnosis. Acta Neurologica Scandinavica. ISSN 0001-6314. 125(5), p. 359–362. doi: 10.1111/j.1600-0404.2011.01609.x.
• Lund, Caroline; Anna, Bremer; Lossius, Morten; Selmer, Kaja Kristine; Brodtkorb, Eylert & Nakken, Karl Otto (2012). Dravets syndrom som årsak til epilepsi og utviklingshemning. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 132(1), p. 44–47. doi: 10.4045/tidsskr.11.0539.
• Nakken, Karl Otto & Lossius, Morten (2011). Buccal midazolam or rectal diazepam for treatment of residential adult patients with serial seizures or status epilepticus. Acta Neurologica Scandinavica. ISSN 0001-6314. 124(2), p. 99–103. doi: 10.1111/j.1600-0404.2010.01474.x.
• Alfstad, Kristin Åshild; Lossius, Morten; Røste, Geir Ketil; Mowinckel, Petter ; Scheie, David & Borota, Olivera Casar [Show all 8 contributors for this article] (2011). Acute postoperative seizures after epilepsy surgery - a long-term outcome predictor? Acta Neurologica Scandinavica. ISSN 0001-6314. 123(1), p. 48–53. doi: 10.1111/j.1600-0404.2010.01343.x.
• Hessen, Erik; Lossius, Morten & Gjerstad, Leif (2011). Improvement in verbal memory after withdrawal of carbamazepine and valproate in patients with well-controlled epilepsy: a randomized, double-blind study. Acta Neurologica Scandinavica. ISSN 0001-6314. 123(6), p. 385–389. doi: 10.1111/j.1600-0404.2010.01452.x.
• Alfstad, Kristin Åshild; Clench-Aas, Jocelyne; Van Roy, Betty; Mowinckel, P; Gjerstad, Leif & Lossius, Morten (2011). Psychiatric symptoms in Norwegian children with epilepsy aged 8-13 years: Effects of age and gender? Epilepsia. ISSN 0013-9580. 52(7), p. 1231–1238. doi: 10.1111/j.1528-1167.2011.03042.x.
• Alfstad, Kristin Åshild; Clench-Aas, Jocelyne; Van Roy, Betty; Mowinckel, Petter ; Gjerstad, Leif & Lossius, Morten (2011). Gender differences in risk-taking behaviour in youth with epilepsy: a Norwegian population-based study. Acta Neurologica Scandinavica. ISSN 0001-6314. 124, p. 12–17. doi: 10.1111/j.1600-0404.2011.01537.x.
• Farmen, Anette Huuse; Lossius, Morten & Nakken, Karl Otto (2009). Flerumettede fettsyrer og epilepsi. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 129(1), p. 26–28.
• Hessen, E; Lossius, Morten & Gjerstad, Leif (2009). Antiepileptic monotherapy significantly impairs normative scores on common tests of executive functions. Acta Neurologica Scandinavica. ISSN 0001-6314. 119(3), p. 194–198. doi: 10.1111/j.1600-0404.2008.01109.x.
• Lossius, Morten; Taubøll, Erik; Mowinckel, Petter & Gjerstad, Leif (2009). Reversible effects of antiepileptic drugs on thyroid hormones in men and women with epilepsy: A prospective randomized double-blind withdrawal study. Epilepsy & Behavior. ISSN 1525-5050. 16(1), p. 64–68. doi: 10.1016/j.yebeh.2009.07.014.
• Lund, Caroline; Haraldsen, Ira Hebold; Lossius, Morten; Bjørnæs, Helge; Lossius, Rasmus Brochmann & Nakken, Karl Otto (2009). Psykogene ikke-epileptiske anfall. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 129(22), p. 2348–2351.
• Hessen, Erik; Lossius, Morten; Reinvang, Ivar & Gjerstad, Leif (2008). Improvement in speeded cognitive processing after anti-epileptic drug withdrawal - A controlled study in mono-therapy patients. In Cummings, Jeffrey L. (Eds.), Progress in neurotherapeutics and neuropsychopharmacology. Cambridge University Press. ISSN 9780521862554. p. 199–210.
• Lossius, Morten; Hessen, E; Mowinckel, P; Stavem, K; Erikssen, J & Gulbrandsen, Pål [Show all 7 contributors for this article] (2008). Consequences of antiepileptic drug withdrawal: A randomized. double-blind study (Akershus Study). Epilepsia. ISSN 0013-9580. 49. doi: 10.1111/j.1528-1167.2007.01323.x.
• Hessen, E; Lossius, Morten; Reinvang, Ivar & Gjerstad, Leif (2007). Slight improvement in mood and irritability after antiepileptic drug withdrawal: A controlled study in patients on monotherapy. Epilepsy & Behavior. ISSN 1525-5050. 10. doi: 10.1016/j.yebeh.2007.01.014.
• Hessen, E; Lossius, Morten; Reinvang, Ivar & Gjerstad, Leif (2007). Influence of major antiepileptic drugs on neuropsychological function: Results from a randomized, double-blind, placebo-controlled withdrawal study of seizure-free epilepsy patients on monotherapy. Journal of the International Neuropsychological Society. ISSN 1355-6177. 13. doi: 10.1017/S13556177070555.
• Hessen, Erik; Lossius, Morten; Reinvang, Ivar & Gjerstad, Leif (2006). Predictors of neuropsychological impairment in seizure-free epilepsy. Epilepsia. ISSN 0013-9580. 47, p. 1870–1878.
• Hessen, Erik; Lossius, Morten; Reinvang, Ivar & Gjerstad, Leif (2006). Influence of major antiepileptic drugs on attention, reaction time and speed of processing. Epilepsia. ISSN 0013-9580. 47, p. 2038–2045.
• Lossius, Morten; Rønning, Ole Martin; Slapø, Geir D; Mowinckel, Petter & Gjerstad, Leif (2005). Poststroke epilepsy: Occurrence and predictors - A long-term prospective controlled study (Akershus stroke study). Epilepsia. ISSN 0013-9580. 46(8), p. 1246–1251.
• Lossius, Morten; Rønning, Ole M.; Slapø, Geir D.; Mowinckel, Petter & Gjerstad, Leif (2005). Poststroke epilepsy: occurrence and predictors--a long-term prospective controlled study. Epilepsia. ISSN 0013-9580. 46(8), p. 1246–1251.
• Lossius, Morten; Rønning, Ole M. & Gjerstad, Leif (2004). [Post-stroke epilepsy]. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 124(5), p. 620–622.

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• Henning, Oliver Johannes; Nakken, Karl Otto & Lossius, Morten Ingvar (2022). All patients with epilepsy, whether at high or low risk of SUDEP, should have access to individually tailored SUDEP information. Epilepsy & Behavior. ISSN 1525-5050. 127. doi: 10.1016/j.yebeh.2021.108418.
• Villagran, Antonia; Duncan, Roderick; Hofoss, Dag & Lossius, Morten Ingvar (2021). Response: The true prevalence of psychogenic nonepileptic seizures is much higher than this. Epilepsia. ISSN 0013-9580. 62(11). doi: 10.1111/epi.17054.
• Alvestad, Silje; Bjørnvold, Marit; Molteberg, Ellen; Lossius, Morten & Landmark, Cecilie Johannessen (2019). Valproat fortsatt viktig for kvinner med generalisert epilepsi. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 139(7), p. 1–2. doi: 10.4045/tidsskr.19.0220.
• lossius, ida marie; Sødal, Hild Flatmark; Nakken, Karl Otto; Svendsen, Torleiv; Lossius, Morten & Landmark, Cecilie Johannessen (2019). Kliniske erfaringer med perampanel – et nytt antiepileptisk legemiddel .
• Svendsen, Torleiv; Lossius, Morten; Nakken, Karl Otto; Baftiu, Arton; Johannessen, Svein Ivar & Landmark, Cecilie Johannessen (2018). Efficacy and tolerability of brivaracetam in patients with refractory epilepsy. An open prospective follow-up study.
• Hansen, Berit M Hjelde; Alfstad, Kristin Åshild; Van Roy, Betty; Henning, Oliver Johannes & Lossius, Morten (2017). Subjectively reported sleep problems in children and youth with epilepsy- associated with objective measures of sleep?
• lossius, ida marie; Landmark, Cecilie Johannessen & Lossius, Morten (2017). Tapering of antiepileptic drugs and liver function.
• Landmark, Cecilie Johannessen; Farmen, Anette Huuse; Burns, Margrete Larsen; Baftiu, Arton; Lossius, Morten & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2017). Pharmacokinetic variability of valproate in women with epilepsy during pregnancy .
• Svendsen, Torleiv; Brodtkorb, Eylert; Lossius, Morten; Nakken, Karl Otto; Baftiu, Arton & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2017). Efficacy and tolerability of lacosamide as add-on treatment in patients with refractory epilepsy and intellectual disability .
• Landmark, Cecilie Johannessen; Farmen, Anette Huuse; Burns, Margrete Larsen; Baftiu, Arton; Lossius, Morten & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2017). Farmakokinetisk variasjon med valproat hos gravide kvinner.
• Landmark, Cecilie Johannessen; Farmen, Anette Huuse; Burns, Margrete Larsen; Baftiu, Arton; Lossius, Morten & Johannessen, Svein Ivar [Show all 7 contributors for this article] (2016). Pharmacokinetic variability of valproate in women of childbearing age and during pregnancy .
• Realfsen, Martha Seim; Bø, Siri M. Hylleraas; Lossius, Morten & Nakken, Karl Otto (2015). Re: Førstegangs generalisert tonisk-klonisk krampeanfall. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 135(22), p. 2025–2026. doi: 10.4045/tidsskr.15.1194.
• Hansen, Berit Marina Hjelde; Alfstad, Kristin Åshild; Van Roy, Betty & Lossius, Morten (2013). Self- and parent- reported sleep problems in children and youths with epilepsy.
• Lossius, Morten; Clench-Aas, Jocelyne; Alfstad, KÅ & Gjerstad, Leif (2011). ATTITUDE TOWARD SCHOOL AND SCHOOLWORK IN NORWEGIAN YOUTH WITH EPILEPSY A POPULATION BASED STUDY-THE AKERSHUS HEALTH PROFILE STUDY. Epilepsia. ISSN 0013-9580. 52, p. 139–139.
• Nakken, Karl Otto & Lossius, Morten (2011). BUCCAL MIDAZOLAM OR RECTAL DIAZEPAM FOR ONGOING SEIZURES - WHAT IS BEST? Epilepsia. ISSN 0013-9580. 52, p. 75–75.
• Lossius, Morten (2010). Skader etter krampeanfall. Tidsskrift for Den norske legeforening. ISSN 0029-2001. 130(11).
• Alfstad, K; Clench-Aas, Jocelyne; Van Roy, Betty; Kristensen, H; Gjerstad, L & Lossius, M (2009). Social anxiety in Norwegian children with epilepsy. A population based study. The Akershus Health Profile Study. Epilepsia. ISSN 0013-9580. 50, p. S231–S231. doi: 10.1111/j.1528-1167.2009.02063.x.
• Lossius, Morten; Erik, T; Mowinckel, P & Gjerstad, Leif (2009). REVERSIBLE EFFECTS OF ANTIEPILEPTIC DRUGS ON THYROID HORMONES IN MEN AND WOMEN WITH EPILEPSY - A PROSPECTIVE RANDOMIZED DOUBLE-BLIND WITHDRAWAL STUDY. Epilepsia. ISSN 0013-9580. 50, p. 146–146.
• Alfstad, Kristin; Clench-Aas, Jocelyne; van Roy, B; Gjerstad, L & Lossius, MI (2009). Changing prevalence of psychiatric symptoms in children and youth with epilepsy. A population based study - The Akershus health profile study. Epilepsia. ISSN 0013-9580. 50, p. 205–206. doi: 10.1111/j.1528-1167.2009.02377_3.x.
• Clench-Aas, Jocelyne; Alfstad, K; Van Roy, B; Gjerstad, L & Lossius, M (2008). Top level sports and use of enhancing drugs in Norwegian youths with epilepsy. A population based study - The Akershus health profile study. Epilepsia. ISSN 0013-9580. 49, p. 214–214.
• Alfstad, K; Clench-Aas, Jocelyne; Van Roy, B; Gjerstad, L & Lossius, M (2008). Early sexual debut in Norwegian youth with epilepsy. A population based study - The Akershus Health Profile Study. Epilepsia. ISSN 0013-9580. 49.
• Clench-Aas, Jocelyne; Lossius, MI & Gjerstad, L (2007). Psychosocial problems in children with epilepsy compared to children with diabetes, asthma and healthy controls - Akershus health profiles for children and youth study. Epilepsia. ISSN 0013-9580. 48, p. 114–115.
• Lossius, Morten; Glench-Aas, J; Mowinkel, P & Gjerstad, Leif (2004). Risk-taking behaviour in patients with epilepsy in junior and senior high school in Norway (the Akershus county health profile for children and youth study). Epilepsia. ISSN 0013-9580. 45, p. 103–103.
• Lossius, Morten; Gjerstad, Leif & Gulbrandsen, Pål (2008). Consequences of withdrawal of antiepileptic drugs on seizure-relapse, cognition, quality of life, heart rate variability, sex hormones, and aspects of behaviour. Unipub forlag.

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