Effects of mandibular advancement devices vs. CPAP on blood pressure in obstructive sleep apnea: a systematic review and meta-analysis of randomized controlled trials

Background Continuous positive airway pressure (CPAP) is the gold standard for obstructive sleep apnea (OSA), but its clinical effectiveness in cardiovascular risk management is often limited by suboptimal adherence. Objective To systematically evaluate and compare the effects of mandibular advancement devices (MAD) vs. CPAP and inactive controls on blood pressure (BP), sleep-related respiratory events, and treatment adherence in patients with OSA. Methods We systematically searched PubMed, Embase, Cochrane Library, and Web of Science from database inception to February 2026. RCTs reporting ambulatory BP outcomes pre- and post-MAD treatment were included. Secondary outcomes included the apnea-hypopnea index (AHI), Epworth Sleepiness Scale (ESS), and objective treatment adherence. Data were pooled using mean differences ( MD ) and 95% confidence intervals (CIs). Results Fourteen independent RCTs (comprising 16 reports) encompassing a total of 1,141 patients, met the inclusion criteria. Compared with inactive controls, MAD showed overall trends of BP reduction. In head-to-head comparisons with CPAP, MAD demonstrated comparable cardiovascular benefits on 24-h and nighttime BP parameters. Notably, MAD achieved a significantly greater reduction in daytime systolic BP compared with CPAP ( MD = −1.99 mmHg, 95% CI: −3.82 to −0.17; p = 0.03). While CPAP demonstrated superior physiological efficacy in reducing AHI ( MD = 8.45 events/h, p 0.001), MAD and CPAP yielded comparable improvements in subjective sleepiness (ESS). Crucially, pooled objective tracking data revealed that MAD had significantly longer nightly adherence than CPAP ( MD = 0.71 h/night, 95% CI: 0.30 to 1.13; p 0.001). Conclusion Despite a physiological inferiority in reducing AHI, MAD appears to offer cardiovascular benefits comparable to CPAP and demonstrates a statistically significant reduction in daytime SBP, which may be partially facilitated by its superior objective adherence. Therefore, for OSA patients who cannot tolerate CPAP, MAD may serve as a viable alternative option for cardiovascular risk management. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD420261303916 , identifier: CRD420261303916.