Impact of continuous positive airway pressure treatment on left ventricular ejection fraction in patients with obstructive sleep apnea: a meta-analysis of randomized controlled trials.

BACKGROUND: It has been known for a long time that obstructive sleep apnea (OSA) is associated with a decreased left ventricular ejection fraction (LVEF). Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA; however, it is unknown whether or not CPAP treatment will improve the LVEF. The aim of the current study was to assess whether or not CPAP treatment improves the LVEF. A meta-analysis was conducted to determine the effect of CPAP treatment on the LVEF among patients with OSA. METHODS: A literature search of PubMed, the Web of Science, and Cochrane Collaboration's database were utilized to identify eligible reports for this trial. Ten randomized controlled trails were examined and the meta-analysis was performed using STATA 11. RESULTS: A significant improvement in the LVEF was observed after CPAP treatment (weighted mean difference(WMD) = 3.59, 95% CI = 1.74-5.44; P<0.001). Subgroup analysis revealed that patients with OSA and heart failure had a significant improvement in the LVEF after CPAP treatment (WMD = 5.18, 95% CI = 3.27-7.08; P