Effect of CPAP on Blood Pressure in Patients With OSA/Hypopnea

Background CPAP is considered the therapy of choice for OSA, but the extent to which it can reduce BP is still under debate. We undertook a systematic review and meta-analysis of randomized controlled trials (RCTs) to quantify the effect size of the reduction of BP by CPAP therapy compared with other passive (sham CPAP, tablets of placebo drug, conservative measures) or active (oral appliance, antihypertensive drugs) treatments. Methods We searched four different databases (MEDLINE, EMBASE, Web of Science, and the Cochrane Library) with specific search terms and selection criteria. Results From 1,599 articles, we included 31 RCTs that compared CPAP with either passive or active treatment. In a random-effects meta-analysis vs passive treatment (29 RCTs, 1,820 subjects), we observed a mean ± SEM net difference in systolic BP of 2.6 ± 0.6 mm Hg and in diastolic BP of 2.0 ± 0.4 mm Hg, favoring treatment with CPAP ( P I 2 , 34%-36%). Conclusions Therapy with CPAP significantly reduces BP in patients with OSA but with a low effect size. Patients with frequent apneic episodes may benefit the most from CPAP.