Previous trials suggested continuous positive airway pressure (CPAP) therapy did not yield a cardiovascular benefit in patients with coronary artery disease (CAD) and obstructive sleep apnea (OSA); however, researchers noted enrollment criteria that excluded patients with OSA with excessive daytime sleepiness (EDS) may have led to the null findings, given those patients could be more likely to benefit from CPAP.
Lead author, Christine Eulenburg, and colleagues performed a secondary analysis of the RICCADSA trial to examine the effect of concurrent EDS in patients with CAD and OSA, and whether the cardiovascular effects of CPAP therapy differed between patients with or without EDS. Based on their findings, investigators concluded adverse cardiovascular outcomes were not meaningfully different between patients with or without EDS. The study was presented in Annals of the American Thoracic Society.
Lack of CPAP Benefit Persists in OSA With EDS
The analysis included 155 patients with CAD and OSA (defined by apnea-hypopnea index ≥15/h) with EDS (defined by Epworth Sleepiness Scale ≥10) who were assigned to CPAP and 244 patients without EDS who were randomized between CPAP and no CPAP. Participants in the non-CPAP group or nonadherent participants in the CPAP group were compared with adherent patients at year 1.
Inverse probability of treatment weighting was applied to mimic randomization of EDS. The primary end point was the first instance of repeat revascularization, myocardial infarction, stroke, or cardiovascular mortality.
At a median follow-up of 52.2 months, the incidences of the primary end point events did not significantly differ between the EDS and non-EDS groups overall. Authors did note, however, that patients who were adherent to CPAP without EDS were associated with significantly decreased cardiovascular risk compared with patients with EDS (adjusted hazard ratio, 0.41; 95% CI, 0.20-0.85; P=.02).
The study’s authors summarized that “adverse cardiovascular outcomes did not differ by degrees of EDS for patients with CAD with OSA who were untreated or nonadherent to treatment,” and that CPAP adherence was associated with reduced adverse outcomes in participants without EDS.
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