Meta-Analysis of Randomized Controlled Trials of Pharmacologic Agents in Non-alcoholic Steatohepatitis

Currently, there is no standardized treatment regimen for non-alcoholic steatohepatitis.

We performed a metaanalysis of high quality randomized controlled trials that evaluated treatment response to metformin, thiazolidinediones (TZDs), and vitamin E in adult patients with non-alcoholic steatohepatitis. Outcome measures were improvement in liver histology, biochemical, and anthropometric measures.

Nine trials met inclusion criteria (3 with TZD, 3 with Metformin, 2 with Vitamin E and 1 with both TZD and Vitamin E.).

With metformin, weighted liver histologic scores for steatosis, ballooning, and fibrosis did not demonstrate significant improvement and lobular inflammation worsened significantly (weighted mean increase 0.21, 95% CI 0.11 to 0.31, P < 0.0001). The liver histology score including steatosis (OR 3.51, 95% CI 2.14 to 5.78) and lobular inflammation (OR 2.65, 95% CI 1.69 to 4.15) improved with TZDs. Hepatic fibrosis (OR 1.58, 95% CI 0.98 to 2.54) and ballooning scores (OR 1.84, 95% CI 0.94 to 3.58) did not demonstrate significant improvement. With Vitamin E, weighted liver histologic scores for steatosis (weighted mean decrease -0.60, 95% CI -0.85 to -0.35, P < 0.0001), lobular inflammation (weighted mean decrease - 0.40, 95% CI -0.61 to -0.20, P = 0.0001) and ballooning (weighted mean decrease -0.30, 95% CI -0.54 to -0.07, P = 0.01) demonstrated significant improvement compared to placebo. Fibrosis did not significantly change.

In patients with NASH, TZDs and Vitamin E improve liver histologic scores but metformin does not. Insulin resistance also improves with both TZDs and metformin. Fibrosis does not improve with any of the agents.