Cardiovascular outcomes in patients with coronary artery disease and nonsleepy versus sleepy obstructive sleep apnoea phenotypes in the RICCADSA trial

Abstract

Background: Recent data suggests that obstructive sleep apnoea (OSA) patients with sleepy phenotype have poorer prognosis compared to nonsleepy patients. Less is known regarding the interaction between sleepiness and adverse outcomes in cardiac patients. Aims: We investigated the incidence of major adverse cardiovascular and cerebrovascular events (MACCE) in coronary artery disease (CAD) patients with OSA. Methods: In a secondary analysis of the RICCADSA trial, data were analyzed from 399 patients (apnoea-hypopnoea index [AHI] ≥15/hr) with nonsleepy (Epworth Sleepiness Scale [ESS]<10) OSA, who were randomized to continuous positive airway pressure (CPAP) (n=122), or no-CPAP (n=122), and 155 sleepy (ESS≥10) patients, who were allocated to CPAP. Untreated/non-users, intermittent CPAP users, and frequent users were compared (0, 0.1-3.9, and ≥4 hours/day, respectively). Propensity scoring was applied to mimic randomization. The primary endpoint was the first event of MACCE. Median follow-up was 52.2 months. Results: The primary outcome did not differ between CAD patients with sleepy vs nonsleepy OSA among untreated/non-CPAP users and intermittent users. In the frequent user group, the sleepy phenotype had a significant risk increase (adjusted hazard ratio 3.08, 95% CI 1.20-7.89; p=0.019) compared with the nonsleepy patients. Conclusions: CAD patients with sleepy and nonsleepy OSA have a similar risk profile when they are untreated or less adherent to CPAP. At least 4 hours of CPAP usage reduces the risk in nonsleepy OSA. Patients with sleepy OSA may need to use the device longer in order to achieve cardiovascular benefits.