Effects of troglitazone on fat distribution in the treatment of male type 2 diabetes

We investigated the efficacy of additional administration of 400 mg troglit azone (+T), which became available as a treatment for type 2 diabetes follo wing the demonstration of its ability to reduce insulin resistance, in comb ination with diet (D + T) or sulfonylurea (S + T) therapy. Body fat area as determined by computed tomographic (CT) scanning at the umbilical level, a s well as several clinical and biochemical parameters of glycemic control a nd lipid metabolism, were compared before and after 3 months of additional treatment with troglitazone. The body mass index (BMI) tended to increase i n both groups (22.7 +/- 0.6 v 23.2 +/- 0.6 kg/m(2) in D + T, nonsignificant [NS]; 22.2 +/- 0.5 v 22.3 +/- 0.5 kg/m(2) in S + T, NS), while it tended t o decrease in the control group (only diet therapy, 23.6 +/- 0.6 v 23.1 +/- 0.8 kg/m(2), NS). Mean blood pressure ([BP] 96 +/- 3 v 89 +/- 4 mm Hg, P < .05) decreased significantly in the D + T group. Changes in the glycemic a nd lipid profile and leptin did not reach statistical significance. The D T group showed a significant decline in immunoreactive insulin ([IRI] 12.4 +/- 1.2 v 8.0 +/- 1.0 mu U/mL, P < .05), reflecting markedly reduced insul in resistance, as well as a significant increase in plasma insulin-like gro wth factor-1 ([IGF-1] 175.7 +/- 14.2 v 189.8 +/- 12.6 ng/mL, P < .05). A sl ight weight gain was associated with a tendency for subcutaneous fat to inc rease, while visceral fat decreased in both troglitazone-treated groups. Th e decrease in the visceral to subcutaneous fat ratio (V/S ratio) was statis tically significant in the D + T group (1.09 +/- 0.11 v 0.94 +/- 0.09, P < .05), while the V/S ratio in the control group did not change. A notable fi nding of this study is the difference in the response to troglitazone betwe en subcutaneous and visceral adipose tissue. It is suggested that troglitaz one may exert beneficial effects by reducing visceral fat. Copyright (C) 19 99 by W.B. Saunders Company.