title: Obstructive sleep apnea is common among patients referred for coronary artery bypass grafting and can be diagnosed by portable monitoring.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is common among patients with coronary artery disease. However, OSA remains largely under recognized. The lack of clinical suspicion and difficulties to access full polysomnography (PSG) are limiting factors. The aim of this study was to evaluate, among patients referred to coronary artery bypass grafting (CABG): (i) the prevalence of OSA, (ii) the association of OSA with clinical symptoms, (iii) the performance of overnight unattended portable monitoring (PM) as an alternative method for the diagnosis of OSA.
  
  
  METHODS
  Consecutive patients referred for CABG were evaluated by standard physical evaluation and validated questionnaires (Berlin questionnaire and Epworth Sleepiness Scale) and underwent full PSG and PM (Stardust II).
  
  
  RESULTS
  We studied 70 consecutive patients (76% men), age 58±7 years (mean±SD), BMI [median (interquartile range)] 27.6 kg/m (25.8-31.1). The prevalence of OSA (full PSG) using an apnea-hypopnea index of at least 5 events/h was 87%. Commonly used clinical traits for the screening of OSA such as the Epworth Sleepiness Scale and neck circumference had low sensitivities to detect OSA. In contrast, the Berlin questionnaire showed a good sensitivity (72%) to detect OSA. PM showed good sensitivity (92%) and specificity (67%) for the diagnosis of OSA.
  
  
  CONCLUSIONS
  OSA is strikingly common among patients referred for CABG. The Berlin questionnaire, but not symptom of excessive daytime sleepiness is a useful tool to screen OSA. PM is useful for the diagnosis of OSA and therefore is an attractive tool for widespread use among patients with coronary artery disease.
authors: Sleep Laboratory, Pulmonary Division, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil. naurynurse@gmail.com
authors: Naury de Jesus
authors: NJ
authors: Danzi-Soares
authors: Pedro Rodrigues
authors: PR
authors: Genta
authors: Flávia Baggio
authors: FB
authors: Nerbass
authors: Rodrigo Pinto
authors: RP
authors: Pedrosa
authors: Flávia Souza Nunes
authors: FS
authors: Soares
authors: Luis Antonio Machado
authors: LA
authors: César
authors: Luciano F
authors: LF
authors: Drager
authors: Robert
authors: R
authors: Skomro
authors: Geraldo
authors: G
authors: Lorenzi-Filho
mesh_terms: D000368:Aged; D001938:Brazil / Q000453:epidemiology; D016009:Chi-Square Distribution; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000453:epidemiology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000295:instrumentation / Q000379:methods*; D011237:Predictive Value of Tests; D015995:Prevalence; D012372:ROC Curve; D012017:Referral and Consultation; D012680:Sensitivity and Specificity; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000453:epidemiology; D011795:Surveys and Questionnaires