Obstructive sleep apnea and risk of cardiovascular disease and all-cause mortality: A meta-analysis of prospective cohort studies

Background: The association between obstructive sleep apnea (OSA) and the incidence of cardiovascular disease (CVD) has been examined in many studies. However, the findings are not entirely consistent across studies. Our goal was to evaluate the association between OSA and risk of CVD and all-causemortality by performing a meta-analysis of prospective cohort studies. Methods: We used generalized least squares regression models to estimate the dose-response relationship. Heterogeneity, subgroup, and sensitivity analyses and publication bias were performed. Results: Twelve prospective cohort studies involving 25,760 participants were included in the meta-analysis. The overall combined relative risks for individuals with severe OSA compared with individuals with an AHI of < 5 were 1.79 (95% confidence interval [CI]: 1.47 to 2.18) for CVD, 1.21 (95% CI: 0.75 to 1.96) for incident fatal and non-fatal coronary heart disease, 2.15 (95% CI: 1.42 to 3.24) for incident fatal and non-fatal stroke, and 1.92 (95% CI: 1.38 to 2.69) for deaths from all-causes. A positive association with CVD was observed for moderate OSA but not for mild OSA. The results of the dose-response relationship indicated that per 10-unit increase in the apnea-hypopnea index was associated with a 17% greater risk of CVD in the general population. Conclusions: This meta-analysis of prospective cohort studies suggests that severe OSA significantly increases CVD risk, stroke, and all-cause mortality. A positive association with CVD was observed for moderate OSA but not for mild OSA. (C) 2013 Published by Elsevier Ireland Ltd.