Lin G, et al. - In a meta-analysis, experts assessed the impact of continuous positive airway pressure (CPAP) on endothelin-1 (ET-1) levels in obstructive sleep apnea (OSA). They searched the Embase, and Cochrane Library and PubMed before March, 2018. They measured the overall effects by the standardized mean difference (SMD) with a 95% confidence interval (CI). Findings suggested a significant association of CPAP treatment among OSA patients to a decrease in ET-1 levels. CPAP therapy was aso affected by apnea–Hypopnea Index (AHI), CPAP therapy duration, and sample size; as seen on subgroup analysis.