Association of non-alcoholic fatty liver disease with major adverse cardiovascular events: A systematic review and meta-analysis

Increasing evidence connects non-alcoholic fatty liver disease (NAFLD) to cardiovascular disease (CVD). The aim of this study is to assess whether and to what extent the excess risk of CVD is conferred by NAFLD in a meta-analysis. We systematically searched PubMed, EmBase, Web of Science, and Cochrane Library for reports published between 1965 and July 3, 2015. Studies that reported data on association between NAFLD and adverse cardiovascular events or mortality were included. Thirty-four studies (164,494 participants, 21 cross-sectional studies, and 13 cohort studies) were included. NAFLD was not associated with overall mortality (HR = 1.14, 95% CI: 0.99-1.32) and CVD mortality (HR = 1.10, 95% CI: 0.86-1.41). However, NAFLD was associated with an increased risk of prevalent (OR = 1.81, 95% CI: 1.23-2.66) and incident (HR = 1.37, 95% CI: 1.10-1.72) CVD. For some specific CVDs, NAFLD was associated with an increased risk of prevalent (OR = 1.87, 95% CI: 1.47-2.37) and incident (HR = 2.31, 95% CI: 1.46-3.65) coronary artery disease (CAD), prevalent (OR = 1.24, 95% CI: 1.14-1.36) and incident (HR = 1.16, 95% CI: 1.06-1.27) hypertension, and prevalent (OR = 1.32, 95% CI: 1.07-1.62) atherosclerosis. In conclusion, the presence of NAFLD is associated with an increased risk of major adverse cardiovascular events, although it is not related to mortality from all causes or CVD.