Positive airway pressure therapy in the prevention of obstructive sleep apnea associated cardiovascular disease: Controversy.

Obstructive sleep apnea (OSA) is a highly prevalent and heterogeneous disorder strongly associated with cardiovascular morbidity and mortality. This review examines the pathophysiological mechanisms linking OSA to cardiovascular disease, and evaluates current evidence regarding the impact of positive airway pressure (PAP) therapy on cardiovascular outcomes and mortality. OSA is an independent risk factor for hypertension, coronary artery disease, heart failure, arrhythmias, stroke, and metabolic dysfunction, mediated by mechanisms including intermittent hypoxia, sympathetic activation, oxidative stress, endothelial dysfunction, and systemic inflammation. Although PAP therapy improves symptoms, apnea-hypopnea index, and intermediate cardiometabolic parameters-particularly among adherent patients-randomized controlled trials have yielded inconsistent results for reducing cardiovascular events and mortality. Emerging evidence indicates that treatment adherence, disease severity, and distinct OSA phenotypes and endotypes substantially influence cardiovascular risk. Methodological limitations, population heterogeneity, and inadequate long-term follow-up continue to fuel controversy, highlighting the need for individualized, phenotype-driven research approaches.