title: Prognostic implication of obstructive sleep apnea diagnosed by post-discharge sleep study in patients presenting with acute coronary syndrome.
abstract: OBJECTIVE
  We aimed to determine the prognostic implications of obstructive sleep apnea (OSA) diagnosed during the recovery phase of acute coronary syndrome (ACS).
  
  
  METHODS
  Patients presenting with ACS and treated with percutaneous coronary intervention were recruited prospectively for a home-based sleep study within 30 days of hospital discharge. Major adverse cardiac and cerebrovascular events (MACCEs) assessed included cardiac death, myocardial infarction, stroke, unplanned revascularization, and hospitalization for heart failure.
  
  
  RESULTS
  Of the 85 patients recruited, 68 successfully completed the study. The median time from percutaneous coronary intervention to sleep study was 14 days (interquartile range: 7.5-27 days). OSA was diagnosed in 24 patients (35.3%) (apnea-hypopnea index > or =15). A drug-eluting stent was implanted into the target lesion in 45 patients (66.2%). None of the study patients had received treatment for OSA. At 24-month follow-up, the MACCE incidence was 34.9% in the OSA group and 5.1% in the non-OSA group (P=0.008, log-rank test). After adjusting for the possible confounding effect of age, gender, coronary intervention indications, hypertension, smoking, and body mass index, OSA remained an independent predictor of MACCEs (adjusted hazard ratio, 6.95; 95% confidence interval, 1.17-41.4; P=0.033).
  
  
  CONCLUSIONS
  OSA diagnosed in patients treated with percutaneous coronary intervention for ACS by post-discharge sleep studies conducted 2 weeks after percutaneous coronary intervention was independently associated with MACCEs at 24-month follow-up.
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Germaine
authors.initials: G
authors.lastname: Loo
authors.affiliation: Division of Respiratory and Critical Care Medicine, National University Health System, Singapore.
authors.forename: Adeline Y
authors.initials: AY
authors.lastname: Tan
authors.affiliation: Department of Cardiology, National University Heart Centre Singapore, Singapore.
authors.forename: Chieh-Yang
authors.initials: CY
authors.lastname: Koo
authors.affiliation: Saw Swee Hock School of Public Health, National University of Singapore, Singapore.
authors.forename: Bee-Choo
authors.initials: BC
authors.lastname: Tai
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Cardiology, National University Heart Centre Singapore, Singapore.
authors.forename: Mark
authors.initials: M
authors.lastname: Richards
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Cardiology, National University Heart Centre Singapore, Singapore. Electronic address: mdclchr@nus.edu.sg.
authors.forename: Chi-Hang
authors.initials: CH
authors.lastname: Lee
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications* / Q000401:mortality / Q000601:surgery; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000175:diagnosis*
keywords: Acute coronary syndrome; Cardiovascular events; Outcomes; Recovery period; Sleep apnea; Stents