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

## TL;DR

This study finds that patients with higher baseline blood pressure experience greater reductions after CPAP therapy for sleep apnea.

## Contribution

Identifies baseline 24-h mean arterial pressure as a predictor of blood pressure reduction following CPAP therapy in OSA patients.

## Key findings

- Baseline 24-h MAP ≥ 96 mmHg predicts greater blood pressure reductions after CPAP treatment.
- CPAP therapy significantly reduces blood pressure in OSA patients.
- Higher baseline MAP correlates with larger absolute and relative reductions in blood pressure measures.

## Abstract

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.

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.

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.

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

CPAP therapy induces a modest reduction in blood pressure among patients with OSA.Patients with a baseline 24‐h MAP of ≥ 96 mmHg experience greater absolute and relative reductions in all blood pressure measures after CPAP treatment than those with a lower MAP.

CPAP therapy induces a modest reduction in blood pressure among patients with OSA.

Patients with a baseline 24‐h MAP of ≥ 96 mmHg experience greater absolute and relative reductions in all blood pressure measures after CPAP treatment than those with a lower MAP.