Effects of Rosiglitazone on Body Fat Mass and Distribution in Type 2 Diabetic Patients

Kim, Hong Kyu; Yoon, Hyo Joong; You, Seung Min; Lee, Ki Young; Park, Hye Young; Kang, Moon Ho

Abstract

BACKGROUND: Rosiglitazone, an insulin-sensitizing drug of the thiazolidinediones class, has a high affinity for the ligands of the peroxisome proliferator activated receptor-gamma(PPAR-gamma), is highly expressed in adipose tissue, and plays an important role in the differentiation of adipocyte. The influence of rosiglitazone was investigated on the total fat mass and regional adiposity in type 2 diabetic patients.
METHODS
Rosiglitazone (4 mg/day) was administered for 6 months to type 2 diabetic patients (n=20) whose glycemic control was unacceptable with the use of other treatments. Measurements of the total, trunk and leg region body fats (by dual energy X-ray absorptiometry) and abdominal fat distributions (by computed tomography) were compared before and after treatment.
RESULTS
Nine patients received rosiglitazone monotherapy and 11 a combined therapy of sulfonylurea and/or metformin. The HbA1C, serum insulin level and homeostasis model assessment insulin resistance index were decreased following the rosiglitazone therapy, but the body weight and BMI were increased. As for the body fat changes, the total (19,382+/-4,786 vs. 22,940+/- 7,300 g, p<0.01), trunk (11,399+/- 2,678 vs. 13,960+/-4,698 g, p<0.01) and leg (4,734+/-1,319 vs. 6,203+/-2,231g, p<0.05) region fat masses were significantly increased. The percentage increase in the total, trunk and leg region fat masses were 20+/-25, 25+/-35 and 58+/-130%, respectively. As for abdominal fat distribution after the treatment, the visceral fat area (225+/-84 vs. 187+/-87 cm2, p<0.05) was significantly decreased, while the subcutaneous fat area tended to increase (178+/-83 vs. 201+/-80 cm2, NS), although these were not statistically significant. The visceral/subcutaneous fat ratio (V/S ratio) was significantly decreased (1.45+/- 0.64 vs. 0.95+/-0.25, p<0.05).
CONCLUSION
Although the total body fat mass was increased following the rosiglitazone therapy, a shift in the body fat distribution, from the visceral to the subcutaneous region, was observed, which may be associated with an improvement in insulin resistance. However, a long-term assessment of the consequences of an increasing total fat mass and change in the body fat distribution will be required.