Effects of continuous positive airway pressure treatment on aortic stiffness in patients with resistant hypertension and obstructive sleep apnea: A randomized controlled trial

Resistant hypertension (RHT) is associated with obstructive sleep apnea (OSA) and increased aortic stiffness, measured by carotid-femoral pulse wave velocity (cf-PWV). We aimed to evaluate in a randomized controlled trial, the effect of Continuous positive airway pressure (CPAP) treatment on cf-PWV in comparison with a control group in patients with RHT and moderate-severe OSA. One-hundred and sixteen patients were randomized to 6-month CPAP treatment (56 patients) or no therapy (60 patients), while keeping their antihypertensive treatment unchanged. Carotid-femoral pulse wave velocity was performed at the beginning and end of the 6-month period. Intention-to-treat intergroup differences in cf-PWV changes were assessed by a generalized mixed-effects model with the allocation group as a fixed factor and adjusted for age, sex, changes in mean arterial pressure and the baseline cf-PWV values. Subgroup sensitivity analyses were performed, excluding patients with low CPAP adherence and low cf-PWV at baseline. CPAP and control groups had similar clinic-laboratorial characteristics. Patients had a mean cf-PWV of 9.4 +/- 1.6 m/s and 33% presented cf-PWV > 10 m/s. During treatment, the control group had a mean increase in cf-PWV of +0.43 m/s (95% confidence interval [CI], +0.14 to +0.73 m/s; p = .005), whereas the CPAP group had a mean increase of +0.03 m/s (95% CI, -0.33 to +0.39 m/s; p = .87), resulting in a mean difference in changes between CPAP and control of -0.40 m/s (95% CI, -0.82 to +0.02 m/s; p = .059). Subgroup analyses did not change the results. In conclusion, a 6-month CPAP treatment did not reduce aortic stiffness, measured by cf-PWV, in patients with RHT and moderate/severe OSA, but treatment may prevent its progression, in contrast to no-CPAP therapy.