Continuous positive airway pressure for adults with obstructive sleep apnea and cardiovascular disease: a meta-analysis of randomized trials.

BACKGROUND: It remains uncertain whether continuous positive airway pressure (CPAP) therapy would significantly impact hard clinical outcomes in patients with obstructive sleep apnea (OSA). This meta-analysis aimed to assess the effects of CPAP in survival and secondary prevention of major cardiovascular events in patients with OSA and cardiovascular disease (CVD).

METHODS: PubMed, Cochrane CENTRAL, LILACS, and SciElo databases (up to January 2018) were searched for randomized trials that compared CPAP with no active treatment in adults with OSA and CVD. The primary outcomes were all-cause death, cardiovascular death, acute myocardial infarction, stroke, and any major cardiovascular event. We used risk ratios (RR) and 95% confidence interval (CI) as the effect measures for dichotomous data, and weighted mean difference (WMD) and 95% CI for continuous variables. We used the random-effects method for meta-analysis.

RESULTS: Nine trials involving 3314 patients contributed data for meta-analysis of at least one outcome. The duration (median) of CPAP treatment varied from one month to 56.9 months. The pooled RR (95% CI) was 0.86 (0.60-1.23, I2  = 0.0%) for all-cause death, 0.58 (0.19-1.74, I2  = 47%) for cardiovascular death, 1.11 (0.76-1.62, I2  = 0.0%) for myocardial infarction, 0.77 (0.46-1.28, I2  = 16%) for stroke, and 0.93 (0.70-1.24, I2  = 49%) for any major cardiovascular event. The quality of evidence for these outcomes was low.

CONCLUSIONS: Low-quality evidence suggests that CPAP therapy does not significantly improve survival or prevent major cardiovascular events in adults with OSA and cardiovascular disease.