title: Quality-adjusted life-years gain and health status in patients with OSAS after one year of continuous positive airway pressure use.
abstract: OBJECTIVE
  To estimate the health utility score and quality-adjusted life-years (QALY) index of obstructive sleep apnea syndrome (OSAS) in patients over 1 y of continuous positive airway pressure (CPAP) treatment.
  
  
  METHODS
  Longitudinal interventional study.
  
  
  METHODS
  The study was carried out in Sao Paulo Sleep Institute, Brazil.
  
  
  METHODS
  Ninety-five patients with OSAS and with apnea-hypopnea index (AHI) > 20 of either sex, body mass index < 40 kg/m(2), and no previous contact with CPAP were included.
  
  
  METHODS
  The participants underwent baseline and titration polysomnographies, clinical evaluation, and ambulatory blood pressure (BP) measurement, completed Short-Form 6 Dimension Health Survey (SF-6D) and Epworth Sleepiness Scale (ESS) questionnaires, and implementation of CPAP. The patients were followed for 1 y.
  
  
  RESULTS
  The mean AHI and age were 57.6 ± 29.2 events/h and 53.3 ± 9.3 y, respectively. One year of CPAP treatment increased the health utility score from 0.611 ± 0.112 to 0.710 ± 0.121 (P < 0.01). Therefore, CPAP resulted in a mean gain of 0.092 QALY/patient. The improvements in utility scores were associated with decreases in the ESS after 1 mo, in systolic BP after 1 y, and in diastolic BP at 6 mo. BP normalization group (≤ 130/85 mmHg) showed higher QALY than that of the non-normalization group (0.10 ± 0.09 versus 0.05 ± 0.10; P = 0.03). One-year ESS score (P = 0.03), diastolic BP reduction P = 0.01) and baseline utility scores (P < 0.01) were significantly associated with QALY gain.
  
  
  CONCLUSIONS
  This study showed a significant QALY/patient gain after 1 y of regular CPAP use. In addition, BP normalization was associated with higher QALY gain. Thus, utility studies can provide more complete analyses of the total benefits of CPAP treatment in patients with OSAS and should be encouraged.
authors.affiliation: Sleep Medicine and Biology Discipline, Psychobiology Department, Universidade Federal de Sao Paulo, Sao Paulo, Brazil.
authors.forename: Camila F
authors.initials: CF
authors.lastname: Rizzi
authors.affiliation: Sleep Medicine and Biology Discipline, Psychobiology Department, Universidade Federal de Sao Paulo, Sao Paulo, Brazil: Sao Paulo Center for Health Economics - GRIDES, Universidade Federal de Sao Paulo, Sao Paulo, Brazil.
authors.forename: Marcos B
authors.initials: MB
authors.lastname: Ferraz
authors.affiliation: Sleep Medicine and Biology Discipline, Psychobiology Department, Universidade Federal de Sao Paulo, Sao Paulo, Brazil.
authors.forename: Dalva
authors.initials: D
authors.lastname: Poyares
authors.affiliation: Sleep Medicine and Biology Discipline, Psychobiology Department, Universidade Federal de Sao Paulo, Sao Paulo, Brazil.
authors.forename: Sergio
authors.initials: S
authors.lastname: Tufik
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D018660:Blood Pressure Monitoring, Ambulatory; D015992:Body Mass Index; D001938:Brazil; D045422:Continuous Positive Airway Pressure / Q000706:statistics & numerical data; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D019057:Quality-Adjusted Life Years; D012890:Sleep / Q000502:physiology; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology* / Q000523:psychology / Q000628:therapy*; D011795:Surveys and Questionnaires; D013997:Time Factors; D016896:Treatment Outcome
keywords: CPAP; obstructive sleep apnea (OSA); quality-adjusted life-years (QALY); utility