Abstract

Summary Background : Increased insulin resistance is the major pathogenic mechanism in the development of non‐alcoholic steatohepatitis. Aim : To investigate the therapeutic effect of metformin, a well‐known insulin‐sensitizing agent, in the treatment of non‐alcoholic steatohepatitis. Methods : Thirty‐six patients with non‐alcoholic steatohepatitis were randomized into two groups. The first group was given lipid and calorie‐restricted dietary treatment alone, and the second group was given metformin 850 mg b.d. plus dietary treatment, for 6 months. The changes in biochemical, sonographic and histological parameters were compared. Results : The mean serum alanine/aspartate aminotransferase, insulin and C‐peptide levels decreased and the index of insulin resistance improved significantly from baseline in the group given metformin. The mean changes in these parameters in the metformin group were significantly greater than those in the group given dietary treatment alone. Although more patients in the metformin group showed improvement in the necro‐inflammatory activity, compared with the group given dietary treatment alone, no significant differences in necro‐inflammatory activity or fibrosis were seen between the groups. Conclusion : The data suggest that improvement of the insulin sensitivity with metformin may improve the liver disease in patients with non‐alcoholic steatohepatitis.