Effect of Continuous Positive Airway Pressure Treatment on Ambulatory Blood Pressures in High-risk Sleep Apnea Patients: a Randomized Controlled Trial

Study Objectives: The long-term effect of continuous positive airway pressure (CPAP) on 24-hour blood pressure (BP) in patients at high risk with obstructive sleep apnea (OSA) is uncertain. We aimed to determine the effect of CPAP treatment on ambulatory BP in individuals with moderate or severe OSA and cardiovascular disease or multiple cardiovascular disease risk factors without severe sleepiness.

Methods: In this randomized, controlled, parallel group study, 169 participants were randomly assigned to CPAP treatment or the control group. The primary outcome was the change in mean 24-hour systolic BP between groups from baseline to the average of 6- and 12-month measurements using mixed-effect linear regression models.

Results: The 24-hour systolic BP did not significantly differ by group, although there was a trend of decrease in the CPAP group (treatment effect -2.7 mm Hg [95% confidence interval -5.9 to 0.6]; = .105) compared with control. CPAP had the greatest effect on nighttime systolic BP (treatment effect -5.9 mm Hg [95% confidence interval -9.9 to -1.9]; = .004). Similar improvements in other nocturnal BP indices were observed.

Conclusions: In patients at high risk with moderate-severe OSA without severe sleepiness, CPAP resulted in modest BP improvements over 6 to 12 months of follow-up, with possibly larger effects for nocturnal BP. Use of office blood pressure may underestimate the effect of CPAP on BP profile in patients with OSA.

Clinical Trial Registration: Registry: ClinicalTrials.gov; Title: Sleep Apnea Intervention for Cardiovascular Disease Reduction; Identifier: NCT01261390; URL: https://clinicaltrials.gov/ct2/show/NCT01261390.

Citation: Zhao YY, Wang R, Gleason KJ, et al. Effect of continuous positive airway pressure treatment on ambulatory blood pressures in high-risk sleep apnea patients: a randomized controlled trial. . 2022;18(8):1899-1907.