title: Autoimmune diseases in adults with atopic dermatitis.
abstract: BACKGROUND
  An increased susceptibility to autoimmune disease has been shown in patients with atopic dermatitis (AD), but data remain scarce and inconsistent.
  
  
  OBJECTIVE
  We examined the co-occurrence of selected autoimmune diseases in adult patients with AD.
  
  
  METHODS
  Nationwide health registers were used. Adult patients with a hospital diagnosis of AD in Denmark between 1997 and 2012 were included as cases (n = 8112) and matched with controls (n = 40,560). The occurrence of autoimmune diseases was compared in the 2 groups. Logistic regression was used to estimate odds ratios.
  
  
  RESULTS
  AD was significantly associated with 11 of 22 examined autoimmune diseases. In addition, AD was associated with having multiple autoimmune comorbidities. Patients with a history of smoking had a significantly higher occurrence of autoimmune comorbidities compared to nonsmokers.
  
  
  CONCLUSIONS
  This study was limited to adult patients with AD. No information about AD severity or degree of tobacco consumption was available. Results from a hospital population of AD patients cannot be generalized to the general population.
  
  
  CONCLUSIONS
  Our results suggest a susceptibility of autoimmune diseases in adult patients with AD, especially in smokers. While we cannot conclude on causality based on these data, an increased awareness of autoimmune comorbidities in patients with AD may be warranted.
authors.affiliation: Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark. Electronic address: yuki.maria.fukuda.andersen.01@regionh.dk.
authors.forename: Yuki M F
authors.initials: YM
authors.lastname: Andersen
authors.affiliation: Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: Alexander
authors.initials: A
authors.lastname: Egeberg
authors.affiliation: Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; The Danish Heart Foundation, Copenhagen, Denmark; The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
authors.forename: Gunnar H
authors.initials: GH
authors.lastname: Gislason
authors.affiliation: Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: Lone
authors.initials: L
authors.lastname: Skov
authors.affiliation: Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; The National Allergy Research Centre, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark.
authors.forename: Jacob P
authors.initials: JP
authors.lastname: Thyssen
mesh_terms: D000328:Adult; D001327:Autoimmune Diseases / Q000150:complications*; D003876:Dermatitis, Atopic / Q000150:complications* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male
keywords: atopic dermatitis; autoimmune disease; comorbidity; epidemiology