Effects of continuous positive airway pressure on blood pressure in patients with resistant hypertension and obstructive sleep apnea: a systematic review and meta-analysis of six randomized controlled trials

OBJECTIVE To evaluate systematically the effects of continuous positive airway pressure (CPAP) on blood pressure in patients with resistant hypertension and obstructive sleep apnea (OSA). METHODS The Cochrane Library, PubMed, ScienceDirect, and the Web of Science were searched for studies investigating the effects of CPAP on blood pressure in patients with resistant hypertension and OSA. The selected studies underwent quality assessment and meta-analysis, as well as being tested for heterogeneity. RESULTS Six randomized controlled trials were included in the meta-analysis. The pooled estimates of the changes in mean systolic blood pressure and mean diastolic blood pressure (as assessed by 24-h ambulatory blood pressure monitoring) were -5.40 mmHg (95% CI: -9.17 to -1.64; p = 0.001; I2 = 74%) and -3.86 mmHg (95% CI: -6.41 to -1.30; p = 0.00001; I2 = 79%), respectively. CONCLUSIONS CPAP therapy can significantly reduce blood pressure in patients with resistant hypertension and OSA.