Obstructive sleep apnea and cardiovascular risk: Meta-analysis of prospective cohort studies

Background: Previous studies suggest obstructive sleep apnea (OSA) may increase cardiovascular risk, but the results are inconclusive due to various limitations. We aimed to systematically evaluate the effect of OSA on the incidence of cardiovascular events by a meta-analysis of prospective cohort studies. Methods: We searched multiple electronic databases for studies that examined the prospective relationship between OSA and incidence of coronary heart disease (CHD), stroke, or total cardiovascular diseases (CVD) among adults. Either fixed-or random-effects models were used to calculate the pooled risk estimates. Sensitivity analysis was conducted to examine the robustness of pooled outcomes. Results: Of 17 studies included, 9 reported results on total CVD, 7 reported on fatal or non-fatal CHD, and 10 reported on fatal or non-fatal stroke. The pooled relative risks (95% confidence interval) for individuals with moderate-severe OSA compared with the reference group were 2.48 (1.98-3.10) for total CVD, 1.37 (0.95-1.98) for CHD, and 2.02 (1.40-2.90) for stroke. These results did not materially change in the sensitivity analyses according to various inclusion criteria. Conclusions: In conclusion, findings from this meta-analysis supported that moderate-severe OSA significantly increased cardiovascular risk, in particular stroke risk. (C) 2013 Elsevier Ireland Ltd. All rights reserved.