title: Increased risk of psoriasis following obstructive sleep apnea: a longitudinal population-based study.
abstract: BACKGROUND
  This study aims to investigate the risk of psoriasis or psoriatic arthritis in patients with obstructive sleep apnea (OSA) compared with age- and gender-matched unaffected individuals, using a nationally representative population-based dataset.
  
  
  METHODS
  We used data from the Taiwan "Longitudinal Health Insurance Database 2000." The study consisted of 2258 patients with OSA and 11,255 matched comparison patients as the study cohort. Each selected subject (n=13,513) in this study was individually traced for a three-year period from their index ambulatory care visits to identify patients who had been diagnosed with psoriasis during the follow-up period. A stratified Cox proportional hazard regression was used to compute the risk of psoriasis between patients with and without OSA.
  
  
  RESULTS
  It showed that, of 13,513 sampled subjects, 0.27% (n=36) had psoriasis during the three-year follow-up period; the percentage was 0.49% and 0.22% for sampled subjects with and without OSA, respectively. After adjusting for the patients' monthly incomes, geographic location, urbanization level, and obesity, the hazard of psoriasis during the three-year follow-up period was 2.30 (95% CI=1.13-4.69, p=0.022) times greater for patients with OSA than for comparison patients.
  
  
  CONCLUSIONS
  Our results suggest that OSA is associated with an increased risk of subsequent psoriasis or psoriatic arthritis.
authors.affiliation: Department of Dermatology, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Ya-Wen
authors.initials: YW
authors.lastname: Yang
authors.forename: Jiunn-Horng
authors.initials: JH
authors.lastname: Kang
authors.forename: Herng-Ching
authors.initials: HC
authors.lastname: Lin
mesh_terms: D000328:Adult; D015535:Arthritis, Psoriatic / Q000453:epidemiology*; D016022:Case-Control Studies; D016208:Databases, Factual / Q000706:statistics & numerical data; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007348:Insurance, Health / Q000706:statistics & numerical data; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011565:Psoriasis / Q000453:epidemiology*; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D013624:Taiwan / Q000453:epidemiology