Effect of vitamin E supplementation on aminotransferase levels in patients with NAFLD, NASH, and CHC: results from a meta-analysis

Abstract

Objective: The antioxidant vitamin E has been extensively employed to treat chronic liver diseases. The aim of this study was to assess the effect of vitamin E supplementation in lowering alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in patients with nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH), and chronic hepatitis C (CHC).

Methods: We searched all publications in PubMed, Web of Science, and Cochrane Library databases up to June 2013. In total, eight articles met the eligibility criteria, among which, two studies about NAFLD, four studies about NASH, and three studies about CHC, were identified and included in the meta-analysis.

Results: According to standardized mean difference and 95% confidence interval, 12.19 (-4.08 to 28.46) for ALT and 6.84 (-3.18 to 16.86) for AST in patients with NAFLD, 4.54 (1.62-7.46) for ALT and 3.55 (1.39-5.71) for AST in patients with NASH, and 0.61 (0.20-1.02) for ALT and 0.68 (0.07-1.29) for AST in patients with CHC, vitamin E supplementation could optimize ALT and AST levels in patients with NASH and CHC, although it was not statistically significantly associated with reduced ALT and AST levels in patients with NAFLD.

Conclusion: To summarize, the evidence currently available supported the theory that vitamin E supplementation can optimize aminotransferase levels for patients with NAFLD, NASH, and CHC, and more well-designed, large-scale clinical trials are encouraged to examine the therapeutic effect of vitamin E for these disorders.

Keywords: Aminotransferase; Chronic hepatitis C; Meta-analysis; Nonalcoholic fatty liver disease; Nonalcoholic steatohepatitis; Vitamin E.