Evaluating the endothelial and metabolic effects of CPAP therapy in obstructive sleep apnea patients: Insights from a comprehensive meta-analysis.

Across a growing body of research, continuous positive airway pressure (CPAP) therapy has been consistently explored as a treatment for obstructive sleep apnea (OSA) due to its potential to mitigate vascular and metabolic risk factors. While the primary benefit of CPAP is its ability to alleviate symptoms of OSA, the broader physiological impacts, particularly on vascular health and metabolic profiles, have garnered increasing attention. This summary evaluates the effect of CPAP on endothelial function, as well as on lipid and glucose metabolism. Across 74 studies, CPAP therapy in adults with OSA was associated with a significant improvement in endothelial function (FMD) and modest, favorable shifts in lipid and glucose profiles. Total cholesterol, LDL-C, and triglycerides decreased; HDL-C showed no meaningful change. Fasting blood sugar declined, whereas HbA1c, insulin, and HOMA-IR generally showed directionally favorable but non-significant pooled effects. Publication bias appeared limited overall (more likely for HbA1c), and sensitivity analyses supported the robustness of the FMD benefit. Study-level moderators (age, sex, BMI, AHI, follow-up) did not consistently explain heterogeneity, although an exploratory ecological meta-regression suggested greater HbA1c reductions tracked with larger FMD gains.