Benefits of continuous positive airway pressure on blood pressure in patients with hypertension and obstructive sleep apnea: a meta-analysis

This meta-analysis was performed to determine the effects of continuous positive airway pressure (CPAP) on blood pressure (BP) in patients with systemic hypertension and obstructive sleep apnea (OSA). A systematic search was conducted using PubMed, Embase, Web of Science, Cochrane Library, and clinicaltrials.gov, without language restrictions. Randomized controlled trials on the treatment of hypertension and OSA with CPAP, compared with sham CPAP or no CPAP, were reviewed. Studies were pooled to obtain weighted mean differences (WMDs) with 95% confidence intervals (CIs). Nineteen trials (enrolling 1904 participants) met the inclusion criteria. CPAP had significant effects on 24-h systolic blood pressure (SBP) (WMD −5.01 mmHg, 95% CI −6.94 to −3.08; P < 0.00001), 24-h diastolic blood pressure (DBP) (WMD −3.30 mmHg, 95% CI −4.32 to −2.28; P < 0.00001), daytime SBP (WMD −4.34 mmHg, 95% CI −6.27 to −2.40; P < 0.0001), daytime DBP (WMD −2.97 mmHg, 95% CI −3.99 to −1.95; P < 0.00001), nighttime SBP (WMD −3.55 mmHg, 95% CI −5.08 to −2.03; P < 0.00001), nighttime DBP (WMD −2.33 mmHg, 95% CI −3.27 to −1.40; P < 0.00001), office SBP (WMD −3.67 mmHg, 95% CI −5.76 to −1.58; P = 0.0006), office DBP (WMD −2.61 mmHg, 95% CI −4.25 to −0.97; P = 0.002), and heart rate (WMD −2.79 beats/min, 95% CI −4.88 to −0.71; P = 0.009). CPAP treatment was associated with BP reduction in patients with systemic hypertension and OSA, except when the follow-up period was shorter than 3 months.