MACE or death risk in obstructive sleep apnoea and the effect of positive airway pressure

Abstract

Rationale: Evidence regarding the efficacy of positive airway pressure (PAP) therapy in reducing the risks of non-fatal major cardiovascular events (NF-MACE) and mortality in patients with obstructive sleep apnoea (OSA) remains controversial. Objectives: This study aims to quantify the impact of PAP therapy on these risks and develop a predictive risk estimator. Methods: We conducted a multicentre, observational, prospective study involving 5358 individuals diagnosed with OSA, with a median follow-up of 14 years (IQR 10-15 years). We derived and validated a risk estimator of NF-MACE (including myocardial infarction, stroke, revascularisation procedures, and congestive heart failure) and all-cause mortality, incorporating PAP adherence alongside clinical and sleep-related data. Results: The cohort's mean (sd) for age was 55±11 years, the Body Mass Index 32.0±5.4 Kg·m-2, and an apnoea-hypopnea index (AHI) of 35 (±22) events/hour; 26% were females, and 1467 (37%) were PAP adherent. Over the follow-up period, 754 participants experienced NF-MACE, while 858 deaths were recorded. Significant predictors included prior cardiovascular events, non-HDL cholesterol 200 mg·dL-1, COPD diagnosis, AHI >30 events/hr, and age >60 years. PAP adherence was protective (OR 0.46; 95% CI: 0.38 to 0.56), and the absolute risk reduction varied depending on the baseline risk (median of 16%, IQR 12-18). The risk estimator yielded an AUROC of 0.75 and a Brier score of 0.17, with 64% sensitivity and 75% specificity. Conclusions: PAP therapy is associated with long-term risk reduction of NF-MACE and mortality in OSA patients, while the developed risk estimator enhances clinical decision-making regarding therapy initiation.