title: Sleep disordered breathing and mortality: eighteen-year follow-up of the Wisconsin sleep cohort.
abstract: BACKGROUND
  Sleep-disordered breathing (SDB) is a treatable but markedly under-diagnosed condition of frequent breathing pauses during sleep. SDB is linked to incident cardiovascular disease, stroke, and other morbidity. However, the risk of mortality with untreated SDB, determined by polysomnography screening, in the general population has not been established.
  
  
  METHODS
  An 18-year mortality follow-up was conducted on the population-based Wisconsin Sleep Cohort sample (n = 1522), assessed at baseline for SDB with polysomnography, the clinical diagnostic standard. SDB was described by the number of apnea and hypopnea episodes/hour of sleep; cutpoints at 5, 15 and 30 identified mild, moderate, and severe SDB, respectively. Cox proportional hazards regression was used to estimate all-cause and cardiovascular mortality risks, adjusted for potential confounding factors, associated with SDB severity levels.
  
  
  RESULTS
  All-cause mortality risk, adjusted for age, sex, BMI, and other factors was significantly increased with SDB severity. The adjusted hazard ratio (HR, 95% CI) for all-cause mortality with severe versus no SDB was 3.0 (1.4,6.3). After excluding persons who had used CPAP treatment (n = 126), the adjusted HR (95% CI) for all-cause mortality with severe versus no SDB was 3.8 (1.6,9.0); the adjusted HR (95% CI) for cardiovascular mortality was 5.2 (1.4,19.2). Results were unchanged after accounting for daytime sleepiness.
  
  
  CONCLUSIONS
  Our findings of a significant, high mortality risk with untreated SDB, independent of age, sex, and BMI underscore the need for heightened clinical recognition and treatment of SDB, indicated by frequent episodes of apnea and hypopnea, irrespective of symptoms of sleepiness.
authors: Department of Population Health Sciences, University of Wisconsin-Madison, Madison, WI, USA. tbyoung@wisc.edu
authors: Terry
authors: T
authors: Young
authors: Laurel
authors: L
authors: Finn
authors: Paul E
authors: PE
authors: Peppard
authors: Mariana
authors: M
authors: Szklo-Coxe
authors: Diane
authors: D
authors: Austin
authors: F Javier
authors: FJ
authors: Nieto
authors: Robin
authors: R
authors: Stubbs
authors: K Mae
authors: KM
authors: Hla
mesh_terms: D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000401:mortality; D002423:Cause of Death; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D016016:Proportional Hazards Models; D012306:Risk; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000175:diagnosis / Q000401:mortality*; D020521:Stroke / Q000401:mortality; D016019:Survival Analysis; D014922:Wisconsin