Outcomes in coronary artery disease patients with sleepy obstructive sleep apnoea on CPAP

Abstract

Coronary artery disease (CAD) patients with obstructive sleep apnoea (OSA) have increased risk for major adverse cardiovascular and cerebrovascular events (MACCEs) compared with CAD patients without OSA. We aimed to address if the risk is similar in both groups when OSA patients are treated. This study was a parallel observational arm of the RICCADSA randomised controlled trial, conducted in Sweden between 2005 and 2013. Patients with revascularised CAD and OSA (apnoea-hypopnoea index (AHI) >= 15 events.h(-1)) with daytime sleepiness (Epworth Sleepiness Scale score. 10) were offered continuous positive airway pressure (CPAP) (n = 155); CAD patients with no OSA (AHI < 5 events.h(-1)) acted as controls (n = 112), as a randomisation of sleepy OSA patients to no treatment would not be ethically feasible. The primary end-point was the first event of MACCEs. Median follow-up was 57 months. The incidence of MACCEs was 23.2% in OSA patients versus 16.1% in those with no OSA (adjusted hazard ratio 0.96, 95% CI 0.40-2.31; p = 0.923). Age and previous revascularisation were associated with increased risk for MACCEs, whereas coronary artery bypass grafting at baseline was associated with reduced risk. We conclude that the risk for MACCEs was not increased in CAD patients with sleepy OSA on CPAP compared with patients without OSA.