Blood pressure improvement with continuous positive airway pressure is independent of obstructive sleep apnea severity

Study Objectives: We sought to perform a patient-level meta-analysis using the individual patient data of the trials identified in our previous study-level meta-analysis investigating the effect of positive airway pressure (PAP) treatment for obstructive sleep apnea (OSA) on blood pressure (BP). Design: Patient-level meta-analysis. Setting: N/A. Participants: 968 adult OSA subjects without major comorbidities drawn from eight randomized controlled trials. Interventions: Therapeutic PAP versus non-therapeutic control conditions (sham-PAP, pill placebo or standard care) over at least one week. Measurements and Results: The mean reductions in BP between PAP and non-therapeutic control arms were -2.27 mm Hg (95% CI -4.01 to -0.54) for systolic BP and -1.78 mm Hg (95% CI -2.99 to -0.58) for diastolic BP. The presence of uncontrolled hypertension at baseline was significantly associated with a reduction in systolic BP of 7.1 mm Hg and diastolic BP of 4.3 mm Hg after controlling for OSA severity (apnea-hypopnea index, Epworth Sleepiness Scale score, PAP level), patient demographics (age, gender, body mass index, use of antihypertensive medication/s), and measures of PAP efficacy (PAP adherence and treatment duration). Conclusions: OSA patients with uncontrolled hypertension are likely to gain the largest benefit from PAP in terms of a substantial reduction in BP, even after controlling for disease severity.