Obstructive sleep apnea (OSA) is associated with increased cardiovascular events in observational studies. Randomized trials have demonstrated continuous positive airway pressure (CPAP) therapy reduces blood pressure, markers of oxidative stress and insulin insensitivity.  Yet, it remains unclear whether treatment with CPAP reduces cardiovascular events.  In the largest study of its kind, 2717 patients aged 45 to 75 years with moderate-to-severe OSA and coronary or cerebrovascular disease were randomized in open-label fashion to receive CPAP treatment or usual care alone. The primary composite end point included cardiovascular death, myocardial infarction, stroke and heart failure with secondary end-points including day-time sleepiness, mood and quality of life indices. At a mean follow-up of 3.7 years, the trial was neutral with no difference in the primary end-point between the CPAP (17.0%) and the usual-care groups (15.4%) (P=0.34), and no difference in the individual components of the primary end-point.  CPAP however significantly improved snoring, daytime sleepiness, mood and health-related quality of life.

Conclusions

This large trial demonstrates no benefit in CPAP over usual care in reducing the burden of cardiovascular events or death in patients with OSA and cardiovascular disease.  CPAP continues to improve patient’s symptoms and quality of life indices and in this regard remains a valuable therapy.

McEvoy RD, Antic NA, Heeley E, Luo Y, Ou Q, Zhang X, Mediano O, Chen R, Drager LF, Liu Z, Chen G, Du B, McArdle N, Mukherjee S, Tripathi M, Billot L, Li Q, Lorenzi-Filho G, Barbe F, Redline S, Wang J, Arima H, Neal B, White DP, Grunstein RR, Zhong N, Anderson CS; SAVE Investigators and Coordinators.  CPAP for Prevention of Cardiovascular Events in Obstructive Sleep Apnea.  N Engl J Med. 2016 Sep 8;375(10):919-31.

Hussain Contractor & James M. McCabe