Association between vitamin E and non-alcoholic steatohepatitis: a meta-analysis

Non-alcoholic fatty liver disease (NAFLD) generally has a relatively favorable clinical course; however, non-alcoholic steatohepatitis (NASH) was much more frequently progresses to cirrhosis and hepatocellular carcinoma. We performed a systematic review and meta-analysis of clinical trials to examine the effects of vitamin E supplementation in improving liver histology in NASH. We performed a comprehensive search of the PubMed, Embase and Cochrane databases through October 2014. Weighted mean differences (WMDs) and their respective 95% confidence intervals (CIs) were calculated to assess the efficacy of vitamin E in improving liver histological scores by using fixed effects or random effects. Standard methods were performed to explore statistical heterogeneity and publication bias. Compared with controls, vitamin E supplementation significantly improved all histological parameters, including steatosis (WMD = -0.62, 95% CI: -0.95, -0.77, P = 0.0002), hepatocyte ballooning (WMD = -0.30, 95% CI: -0.56, -0.04, P = 0.03), lobular inflammation (WMD = -0.39, 95% CI: -0.67, -0.11, P = 0.007) and fibrosis (WMD = -0.39, 95% CI: -0.72, -0.06, P = 0.02). Our analysis also indicated the absence of publication bias between NASH and Vitamin E intake. This meta-analysis indicates that vitamin E supplementation had a significant and positive effect in the improvement of steatosis, ballooning degeneration, lobular inflammation and fibrosis in patients with NASH.