Predictors of Blood Pressure Fall With Continuous Positive Airway Pressure Treatment in Hypertension With Coronary Artery Disease and Obstructive Sleep Apnea.

Background: The present study aimed to investigate the predictors of changes in blood pressure (BP) with continuous positive airway pressure (CPAP) treatment in hypertensive patients with coronary heart disease (CHD) and obstructive sleep apnea (OSA).

Methods: Seventy-one hypertensive patients with CHD and OSA were enrolled in this study. Daytime systolic BP (SBP), diastolic BP (DBP), Epworth Sleepiness Scale (ESS), and anthropometric characteristics were assessed at baseline and follow-up.

Results: Sixty-six patients completed the study. The median follow-up period was 36 months (interquartile range, 24-60 months). The mean duration of CPAP application was 4.3 ± 1.2 hours per night. From baseline to follow-up, SBP and DBP were reduced by 5.6 mm Hg (95% confidence interval [CI], 3.0-8.1) and 3.0 mm Hg (95% CI, 0.8-5.3), respectively. Daytime somnolence was significantly improved (ESS, from 9.5 ± 3.4 at baseline to 3.6 ± 2.0 at follow-up; P < 0.001); the mean improvement in ESS was 6.0 (95% CI, 5.1-6.9). Correlation analysis of the fall in mean BP (MBP) showed that baseline MBP, change in ESS, heart rate, and CPAP compliance showed a positive correlation, whereas the baseline body mass index (BMI) and ESS had an inverse relationship. Stepwise multiple linear regression analysis, however, indicated that only baseline BMI, baseline MBP, and CPAP compliance were independently correlated with the fall in MBP.

Conclusions: Long-term CPAP treatment reduces BP in hypertensive patients with CHD and moderate/severe OSA; baseline BMI, baseline MBP, and CPAP compliance are independent predictors of the decrease in BP with CPAP treatment in these patients.