title: Autoimmune comorbid diseases associated with lichen planus: a nationwide case-control study.
abstract: BACKGROUND
  Lichen planus (LP) is a chronic inflammatory disorder with unknown aetiology. The association between LP and various autoimmune diseases has been reported, but nationwide study of the relationship of LP with associated diseases is quite limited.
  
  
  OBJECTIVE
  Our study aims to clarify the association between LP and a variety of autoimmune diseases in Taiwanese.
  
  
  METHODS
  Data were obtained from the National Health Insurance Research Database (NHIRD) of Taiwan from 1997 to 2011. In total, 12,427 patients with LP and 49,708 age- and gender-matched controls were enrolled.
  
  
  RESULTS
  Among patients with LP, there were significant associations with systemic lupus erythematosus (SLE) (multivariate odds ratio [mOR]: 2.87; 95% CI: 1.97-4.17), Sjögren's syndrome (mOR: 3.75; 95% CI: 2.66-5.28), dermatomyositis (mOR: 6.34; 95% CI: 1.82-22.16), vitiligo (mOR: 2.09; 95% CI: 1.31-3.32) and alopecia areata (mOR: 2.82; 95% CI: 2.20-3.62). On gender-stratified analyses, SLE and alopecia areata were significantly associated with LP in both genders. The association with Sjögren's syndrome was significant only in female patients. The associations with dermatomyositis and vitiligo became insignificant in both genders.
  
  
  CONCLUSIONS
  Lichen planus is associated with various autoimmune diseases. Further study is required to elucidate the possible underlying mechanisms and roles of autoimmunity in the aetiology of LP.
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: P-I
authors.initials: PI
authors.lastname: Chung
authors.affiliation: Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.|Department of Dermatology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: C-Y
authors.initials: CY
authors.lastname: Hwang
authors.affiliation: Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.|Department of Dermatology, Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Chen
authors.affiliation: Institute of Public Health, National Yang-Ming University, Taipei, Taiwan.
authors.forename: M-W
authors.initials: MW
authors.lastname: Lin
authors.affiliation: Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: T-J
authors.initials: TJ
authors.lastname: Chen
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: T-C
authors.initials: TC
authors.lastname: Hua
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: L-C
authors.initials: LC
authors.lastname: Wu
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: S-Y
authors.initials: SY
authors.lastname: Chu
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: C-C
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: D-D
authors.initials: DD
authors.lastname: Lee
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Y-T
authors.initials: YT
authors.lastname: Chang
authors.affiliation: Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Department of Dermatology, National Yang-Ming University, Taipei, Taiwan.|Department of Dermatology, National Defense Medical Center, Taipei, Taiwan.
authors.forename: H-N
authors.initials: HN
authors.lastname: Liu
mesh_terms: D001327:Autoimmune Diseases / Q000150:complications*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008010:Lichen Planus / Q000150:complications*; D008297:Male; D008875:Middle Aged; D013624:Taiwan