Background: Knowledge about the prevalence of obstructive sleep apnea (OSA) in coronary artery disease (CAD) is insufficient. The aim of the current report was to evaluate the occurrence and predictors of OSA among revascularized patients with CAD within the framework of a randomized controlled trial (Randomized Intervention with CPAP in Coronary Artery Disease and Sleep Apnea [RICCADSA]), evaluating the impact of continuous positive airway pressure on cardiovascular outcomes in CAD patients with OSA.
Material and methods: All patients undergoing percutaneous coronary intervention or coronary artery bypass grafting between September 2005 and November 2010 (n = 1,291) were invited to participate. Anthropometrics and medical history were obtained, ambulatory sleep recording was performed, and all subjects completed the Epworth Sleepiness Scale (ESS) questionnaire.
Results: In total, 662 patients participated in the sleep study. OSA, defined as an apnea-hypopnea index equal to or greater than 15/hour, was found among 422 (63.7%). The prevalence of hypertension was 55.9%; obesity (body mass index ≥ 30 kg/m²), 25.2%; diabetes mellitus, 22.1%; and current smoking, 18.9%. The patients with CAD who did not participate in the study demonstrated an almost similar anthropometric and clinical profile compared with the studied group. The majority (61.8%) of the patients with OSA were nonsleepy (ESS score < 10). Patients with OSA had a higher prevalence of obesity, hypertension, diabetes mellitus, and history of atrial fibrillation, whereas current smoking was more common in the non-OSA group. Age, male sex, body mass index, and ESS score, but not comorbidities, were independent predictors of OSA.
Conclusions: The occurrence of unrecognized OSA in this revascularized CAD cohort was higher than previously reported. We suggest that OSA should be considered in the secondary prevention protocols in CAD.