Treatment of Sleep Apnea with Positive Airway Pressure and Its Association with Diastolic Dysfunction: A Systematic Review and Meta-Analysis

Background: This meta-analysis assessed the effect of long-term (> 6 weeks) noninvasive positive airway pressure (PAP) on diastolic function in patients with obstructive sleep apnea (OSA). Methods: We searched the databases for randomized clinical trials including Ovid MEDLINE, Ovid Embase Scopus, Web of Science, Google Scholar, and EBSCO CINAHL from inception up to December 20, 2019. The search was not restricted to time, publication status, or language. Two independent investigators screened the studies and extracted the data, in duplicate. Risk of bias was assessed using Cochrane collaboration tools. Results: A total of 2,753 abstracts were resulted from literature search. A total of 9 randomized clinical trials assessing the effect of long-term (> 6 weeks) PAP on diastolic function in patients with OSA including 833 participants were included. The following echo parameters were found in treated patients: a decrease in deceleration time (-39.49 ms CI [-57.24, -21.74]; p = 0.000), isovolumic relaxation time (-9.32 ms CI [-17.08, -1.57]; p = 0.02), and the ratio of early mitral inflow velocity to mitral annular early diastolic velocity (-1.38 CI [-2.6, -0.16]; p = 0.03). However, changes in left-atrial volume index and the ratio of early to late mitral inflow velocities were not statistically different. The risk of bias was mild to moderate among the studies. Conclusion: Our results suggest that chronic treatment of moderate to severe OSA with noninvasive PAP is associated with improvement in echocardiographic findings of diastolic dysfunction.