Cardiovascular Morbidity and Mortality Related to Non-alcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

Whether non-alcoholic fatty liver disease (NAFLD) is a cardiovascular (CV) risk factor is debated. We performed a systematic review and meta-analysis to assess the CV morbidity and mortality related to NAFLD in the general population, and to determine whether CV risk is comparable between lean and non-lean NAFLD phenotypes. We searched multiple databases, including PubMed, Embase, and the Cochrane Library, for observational studies pub-lished through 2022 that reported the risk of CV events and mortality. Pooled odds ratios (ORs) and 95% confi-dence intervals (CIs) for all-cause mortality, CV mor-tality, myocardial infarction (MI), stroke, atrial fibrillation (AF), and major adverse cardiovascular and cerebrovascular events (MACCE) were assessed through random-effect meta-analysis. We identified 33 studies and a total study population of 10,592,851 indi-viduals (mean age 53 +/- 8; male sex 50%; NAFLD 2, 9%). Mean follow-up was 10 +/- 6 years. Pooled ORs for all-cause and CV mortality were respectively 1.14 (95% CI, 0.78-1.67) and 1.13 (95% CI, 0.57-2.23), indicating no significant association between NAFLD and mortal-ity. NAFLD was associated with increased risk of MI (OR 1.6; 95% CI, 1.5-1.7), stroke (OR: 1.6; 95% CI, 1.2-2.1), atrial fibrillation (OR: 1.7; 95% CI, 1.2-2.3), and MACCE (OR: 2.3; 95% CI, 1.3-4.2). Compared with non-lean NAFLD, lean NAFLD was associated with increased CV mortality (OR: 1.50; 95% CI, 1.1-2.0), but similar all-cause mortality and risk of MACCE. While NAFLD may not be a risk factor for total and CV mortality, it is associated with excess risk of non-fatal CV events. Lean and non-lean NAFLD phe-notypes exhibit distinct prognostic profiles and should receive equitable clinical care. (Curr Probl Cardiol 2023;48:101643.)