Evaluation of subclinical cardiac damage in biopsy-proven nonalcoholic fatty liver disease: a systematic review and meta-analysis

BACKGROUND: Data on the association of nonalcoholic fatty liver disease (NAFLD) with subclinical cardiac damage are scanty. We performed a systematic review to provide comprehensive information on subclinical cardiac alterations among NAFLD subjects. METHODS: PubMed and the Cochrane Library were searched to identify studies comparing subclinical cardiac damage between NAFLD and healthy adults. We also searched PROSPERO to check for any similar meta-analysis in progress in order to avoid duplication with our study. Conference abstracts and the reference lists of relevant studies and systematic reviews were perused. The Newcastle-Ottawa quality assessment scale for case-control and cohort studies were used to assess study quality. RESULTS: Seven studies were finally included in the meta-analysis (1 cross sectional and 6 case-control), with a total of 602 individuals (362 patients with NAFLD). Epicardial fat thickness were statistically significantly higher in patients with NAFLD than in controls (mean difference [MD] 1.17, 95% confidence interval [CI] 0.45-1.89, I(2)=89%). Global longitudinal strain was lower in NAFLD, to a statistically significant degree (MD -3.17, 95%CI -5.09 to -1.24, I(2)=89%). However, significant heterogeneity of the findings was observed. CONCLUSIONS: Our findings indicate that NAFLD is related to subclinical cardiac damage. Further studies with a larger number of biopsy-proven NAFLD patients are needed to confirm this finding. Preventive and therapeutic interventions early in the course of the disease might decrease morbidity in this high-risk patient group.