title: Clustering of autoimmune diseases in patients with rosacea.
abstract: BACKGROUND
  Rosacea is a common inflammatory skin condition that shares genetic risk loci with autoimmune diseases such as type 1 diabetes mellitus (T1DM) and celiac disease. A recent genomewide association study identified 90 genetic regions associated with T1DM, celiac disease, multiple sclerosis, and/or rheumatoid arthritis, respectively. However, a possible association with rosacea was not investigated.
  
  
  OBJECTIVE
  We evaluated the association between rosacea and T1DM, celiac disease, multiple sclerosis, and rheumatoid arthritis, respectively.
  
  
  METHODS
  We performed a population-based case-control study. A total of 6759 patients with rosacea were identified and matched with 33,795 control subjects on age, sex, and calendar time. We used conditional logistic regression to calculate crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs).
  
  
  RESULTS
  After adjustment for smoking and socioeconomic status, patients with rosacea had significantly increased ORs for T1DM (OR 2.59, 95% CI 1.41-4.73), celiac disease (OR 2.03, 95% CI 1.35-3.07), multiple sclerosis (OR 1.65, 95% CI 1.20-2.28), and rheumatoid arthritis (OR 2.14, 95% CI 1.82-2.52). The association was mainly observed in women.
  
  
  CONCLUSIONS
  We were unable to distinguish between the different subtypes and severities of rosacea.
  
  
  CONCLUSIONS
  Rosacea is associated with T1DM, celiac disease, multiple sclerosis, and rheumatoid arthritis, respectively, in women, whereas the association in men only reached statistical significance for rheumatoid arthritis.
authors.affiliation: National Allergy Research Center, Department of Dermato-Allergology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark. Electronic address: alexander.egeberg@gmail.com.
authors.forename: Alexander
authors.initials: A
authors.lastname: Egeberg
authors.affiliation: Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: Peter Riis
authors.initials: PR
authors.lastname: Hansen
authors.affiliation: Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Danish Heart Foundation, Copenhagen, Denmark; National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
authors.forename: Gunnar Hilmar
authors.initials: GH
authors.lastname: Gislason
authors.affiliation: National Allergy Research Center, Department of Dermato-Allergology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: Jacob Pontoppidan
authors.initials: JP
authors.lastname: Thyssen
mesh_terms: D000328:Adult; D017677:Age Distribution; D001327:Autoimmune Diseases / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology; D016022:Case-Control Studies; D002446:Celiac Disease / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology; D016000:Cluster Analysis; D015897:Comorbidity; D016001:Confidence Intervals; D016208:Databases, Factual; D003718:Denmark / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology; D005260:Female; D055106:Genome-Wide Association Study; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D012213:Rheumatic Fever / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology; D018570:Risk Assessment; D012393:Rosacea / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology*; D017678:Sex Distribution; D055815:Young Adult
keywords: celiac disease; diabetes; epidemiology; multiple sclerosis; rheumatoid arthritis; rosacea