Effect of nicotinamide on C-peptide levels in insulin-dependent diabetes mellitus

The aim of this study is to assess the effect of nicotinamide to c-peptide levels in children during the first six weeks of insulin-dependent diabetes mellitus (IDDM). Thirty-eight children and adolescents, with recent diagnosis (≤ 6 weeks) of IDDM were studied. Patients were randomized in two groups. In Group A patients received insulin and placebo, while in group B insulin and nicotinamide. Serum c-peptide levels were measured at 0, 3, 6, 9 and 12 months. The total dose of insulin administered the day preceding each sampling was recorded. Results: there was a significant difference between the various average values of c-peptide levels during the second trimester with p=0.01 for group A and p=0.02 for group B. No statistically significant difference was found between the two groups. Similar findings were observed for insulin-dose. Toxicity was negligible and similar in both groups. In conclusion, the treatment of newly diagnosed IDDM with NA does not significantly affect c-peptide levels for a period of time exceeding 6 months. However, this small-size pilot study should be confirmed by a large randomized study with different design involving NA treatment before clinical IDDM.