RT Journal Article
SR Electronic
T1 Familial Aggregation and Heritability of Sarcoidosis: A Swedish Nested Case-Control Study
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 1800385
DO 10.1183/13993003.00385-2018
A1 Marios Rossides
A1 Johan Grunewald
A1 Anders Eklund
A1 Susanna Kullberg
A1 Daniela Di Giuseppe
A1 Johan Askling
A1 Elizabeth V. Arkema
YR 2018
UL http://erj.ersjournals.com/content/early/2018/06/14/13993003.00385-2018.abstract
AB Sarcoidosis is believed to be caused by both genetic and environmental risk factors, but the proportion of the susceptibility to sarcoidosis which is mediated by genetics remains unknown. We aimed to estimate the familial aggregation and heritability of sarcoidosis using a case-control-family study design and population-based Swedish registers.We identified 23 880 individuals with visits for sarcoidosis in the National Patient Register using ICD codes (1964‒2013). Information Löfgren's syndrome was available for a subset diagnosed at Karolinska University Hospital. General population controls were matched to cases (10:1). Relatives of cases and controls were identified from the Multi-Generation Register and ascertained for sarcoidosis in the Patient Register. We estimated familial relative risks (RR) for sarcoidosis using conditional logistic regression and the heritability using biometric models.Having ≥1 first degree relative with sarcoidosis was associated with a 3.7-fold increase in the risk for sarcoidosis (95% CI 3.4−4.1). The RR increased in those with ≥2 relatives (RR 4.7) and in Löfgren's syndrome (RR 4.1). The heritability was 39% (95% CI 12−65).This large investigation showed that having a relative with sarcoidosis is a very strong risk factor for the disease. Genetic variation is an important, albeit partial, contributing factor to the risk for sarcoidosis.FootnotesThis manuscript has recently been accepted for publication in the European Respiratory Journal. 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 ERJ online. Please open or download the PDF to view this article.Conflict of interest: Dr. Rossides has nothing to disclose.Conflict of interest: Dr. Grunewald has nothing to disclose.Conflict of interest: Dr. Eklund has nothing to disclose.Conflict of interest: Dr. Kullberg has nothing to disclose.Conflict of interest: Dr. Di Giuseppe has nothing to disclose.Conflict of interest: Dr. Askling has nothing to disclose.Conflict of interest: Dr. Arkema reports grants from Swedish Heart-Lung Foundation, grants from Swedish Society of Medicine, during the conduct of the study.