RATIONALE:
Obstructive sleep apnea is common in patients with coronary artery disease, many of whom do not report daytime sleepiness. First-line treatment for symptomatic obstructive sleep apnea is continuous positive airway pressure, but its value in patients without daytime sleepiness is uncertain.
OBJECTIVE:
To determine the effects of continuous positive airway pressure on long-term adverse cardiovascular outcome risk in coronary artery disease patients with nonsleepy obstructive sleep apnea.
METHODS:
This single-center, prospective, randomized, controlled, open-label, blinded evaluation trial was conducted between December 2005 and November 2010. Consecutive patients with newly revascularized coronary artery disease and obstructive sleep apnea (apnea-hypopnea index ≥15/h) without daytime sleepiness (Epworth Sleepiness Scale score <10) were randomized to auto-titrating continuous positive airway pressure (n=122) or no positive airway pressure (n=122).
MEASUREMENTS:
The primary endpoint was the first event of repeat revascularization, myocardial infarction, stroke or cardiovascular mortality.
MAIN RESULTS:
Median follow-up was 57 months. The incidence of the primary endpoint did not differ significantly in patients who did versus did not receive positive airway pressure (18.1% vs. 22.1%; hazard ratio 0.80; 95% confidence interval 0.46-1.41; P=0.449). Adjusted on-treatment analysis showed a significant cardiovascular risk reduction in those who used continuous positive airway pressure for ≥4 vs <4 h/night or did not receive treatment (hazard ratio 0.29; 95% confidence interval 0.10-0.86; P=0.026).
CONCLUSIONS:
Routine prescription of continuous positive airway pressure to coronary artery disease patients with nonsleepy obstructive sleep apnea did not significantly reduce long-term adverse cardiovascular outcomes in the intention-to-treat population. There was a significant reduction after adjustment for baseline comorbidities and compliance with the treatment. Clinical trial registration available at www.clinicaltrials.gov, ID NCT00519597.