TY - JOUR T1 - Sarcoidosis in Iceland—a nationwide study epidemiology, clinical picture, and environmental exposure JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00550-2021 SP - 00550-2021 AU - Sigridur Olina Haraldsdottir AU - Jon Gunnlaugur Jonasson AU - Kristin Bara Jorundsdottir AU - Haraldur Jon Hannesson AU - Thorarinn Gislason AU - Bjorn Gudbjornsson Y1 - 2021/01/01 UR - http://openres.ersjournals.com/content/early/2021/09/29/23120541.00550-2021.abstract N2 - Background This nationwide study aimed to elucidate the incidence and clinical characteristics of tissue-verified sarcoidosis in Iceland. A secondary aim was to analyse sex differences and identify possible environmental factors contributing to the pathological process.Materials and Methods This is a descriptive study covering 36 years (January 1st, 1981, through December 31st, 2016). Histopathological reports and electronic hospital discharge registries were reviewed in context for granulomas and/or sarcoidosis. National data were used for comparison regarding smoking habits and occupation, adjusted for age, gender and year of diagnosis. The data were stored in FileMaker and calculations were made by extracting data from this database to the statistical software package R.Results A total of 418 patients (54% females) were diagnosed with tissue-verified sarcoidosis. The incidence rate was 4.15/100 000/year, similar among females and males. The average age at diagnosis was higher among females (53.0±14.2 years) than males (48.2±13.8 years). Fatigue was the most frequent single symptom (49.7%), but when all respiratory symptoms were grouped, they were the most frequent symptoms (60%). No significant difference was found between smoking status and sarcoidosis. Possible hazardous exposure in the workplace was reported by 19.4% of the cases.Conclusion The incidence of sarcoidosis in Iceland was higher than in an Asian population where the same inclusion criteria were applied. The clinical picture diverges partly from that in the Asian population but resembles that among other Caucasians. Fatigue and respiratory symptoms were predominant. The biphasic pattern of age at disease debut seen elsewhere among females was not evident in Iceland.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Sigríður Ólína Haraldsdóttir reports support for the present manuscript from The Science Fund of Landspitali, University Hospital of Iceland, and The Icelandic Respiratory Society.Conflict of interest: Jon Gunnlaugur Jonasson has nothing to disclose.Conflict of interest: Kristin Bara Jorundsdottir has nothing to disclose.Conflict of interest: Haraldur Jon Hannesson reports support for the present manuscript from The Science Fund of Landspitali, University Hospital of Iceland.Conflict of interest: Thorarinn Gislason has nothing to disclose.Conflict of interest: Bjorn Gudbjornsson reports consulting fees from Novartis, outside the submitted work. Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Amgen and Novartis, outside the submitted work. ER -