title: Sleep apnea and risk of pneumonia: a nationwide population-based study.
abstract: BACKGROUND
  Evidence evaluating the risk of pneumonia in patients with obstructive sleep apnea is limited and mostly focuses on patients who receive continuous positive airway pressure (CPAP) therapy or on pediatric patients. We aimed to explore the risk of incident pneumonia among adults with sleep apnea, either with or without the need of CPAP therapy.
  
  
  METHODS
  From Jan. 1, 2000, we identified adult patients with sleep apnea from the Taiwan National Health Insurance Research Database. A control cohort without sleep apnea, matched for age, sex and comorbidities, was selected for comparison. The 2 cohorts were followed until Dec. 31, 2010, and observed for occurrence of pneumonia.
  
  
  RESULTS
  Of the 34,100 patients (6816 study patients and 27,284 matched controls), 2757 (8.09%) had pneumonia during a mean follow-up period of 4.50 years, including 638 (9.36%) study patients and 2119 (7.77%) controls. Kaplan-Meier analysis showed a higher incidence of pneumonia among patients with sleep apnea (log rank test, p < 0.001). After multivariate adjustment, patients with sleep apnea experienced a 1.20-fold (95% confidence interval 1.10-1.31) increase in incident pneumonia. The risk was even higher among patients who received CPAP therapy.
  
  
  CONCLUSIONS
  Sleep apnea appeared to confer a higher risk for future pneumonia, possibly in a severity-dependent manner.
authors.forename: Vincent Yi-Fong
authors.initials: VY
authors.lastname: Su
authors.forename: Chia-Jen
authors.initials: CJ
authors.lastname: Liu
authors.forename: Hsin-Kai
authors.initials: HK
authors.lastname: Wang
authors.forename: Li-An
authors.initials: LA
authors.lastname: Wu
authors.forename: Shi-Chuan
authors.initials: SC
authors.lastname: Chang
authors.forename: Diahn-Warng
authors.initials: DW
authors.lastname: Perng
authors.forename: Wei-Juin
authors.initials: WJ
authors.lastname: Su
authors.forename: Yuh-Min
authors.initials: YM
authors.lastname: Chen
authors.forename: Elizabeth Ya-Hsuan
authors.initials: EY
authors.lastname: Lin
authors.forename: Tzeng-Ji
authors.initials: TJ
authors.lastname: Chen
authors.forename: Kun-Ta
authors.initials: KT
authors.lastname: Chou
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D016022:Case-Control Studies; D015897:Comorbidity; D045422:Continuous Positive Airway Pressure / Q000379:methods; D016208:Databases, Factual; D005260:Female; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D011379:Prognosis; D016016:Proportional Hazards Models; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D015996:Survival Rate; D013624:Taiwan / Q000453:epidemiology