Predicting Significant Blood Pressure Reduction Through Ambulatory Blood Pressure Monitoring in Patients With Obstructive Sleep Apnea Treated With Continuous Positive Airway Pressure.

OBJECTIVE: Continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea (OSA) results in a modest reduction in blood pressure. This study aimed to identify parameters from 24-h ambulatory blood pressure monitoring (ABPM) that are predictive of treatment response. METHODS: Treatment-naïve patients with OSA were prospectively recruited from the Centre for Sleep Medicine and Science at Beijing Anzhen Hospital between July 2023 and April 2025. All participants underwent 24-h ABPM assessments before and after 3-month CPAP therapy. Correlations between the baseline ABPM data and post-CPAP changes in blood pressure were analyzed. Multivariate analysis was used to determine whether specific baseline blood pressure cutoffs independently predicted a clinically significant reduction in blood pressure. RESULTS: Good CPAP adherence (median usage: 6.1 h/night and 6.0 days/week; residual apnea-hypopnea index: 1.7 events/h) was achieved among 51 recruited patients (92.2% male, median age 40.5 years). After 3 months of CPAP treatment, significant reductions were observed in nearly all blood pressure measurements. Baseline 24-h mean arterial pressure (MAP) was positively correlated with the reduction in all 24-h blood pressure measures, all nighttime blood pressure measures, and daytime MAP. Compared with patients with 24-h MAP < 96 mmHg, those with baseline 24-h MAP ≥ 96 mmHg experienced relatively high absolute and relative reductions in all blood pressure measures. CONCLUSIONS: Baseline 24-h MAP effectively predicts blood pressure reduction following CPAP therapy in patients with OSA, demonstrating the clinical value of an ABPM-guided strategy for managing patients with comorbid OSA and hypertension. TRIAL REGISTRATION: ChiCTR2300067728.