Troglitazone is effective in approximately 50% in patients with
type 2 diabetes (
NIDDM). In this study, we investigated the relations between serum
leptin levels and clinical efficacy of
troglitazone. Forty-five type 2 diabetic patients (23 men and 22 women) from our outpatient clinic were treated with
troglitazone 400 mg daily for 12 weeks. Fasting plasma
glucose (FPG), HbA1c,
body weight, serum
insulin and
leptin concentrations were measured before and after
troglitazone treatment. After 12 weeks of
troglitazone treatment, FPG (before versus after, 179+/-33 vs. 138+/-26 mg/dl, mean+/-SD), HbA1c (7.8+/-1.3 vs. 6.9+/-1.0%), IRI (8.3+/-4.3 vs. 6.3+/-3.4 microU/ml) and HOMA-R index (homeostasis model assessment of
insulin resistance) (3.8+/-2.4 vs. 2.2+/-1.3) decreased significantly, while body mass index (BMI) slightly increased (26.3+/-3.5 vs. 26.6+/- 3.6 kg/m(2)), and serum
leptin remained unchanged (8.5+/-7.2 vs. 9.1+/-8.7 ng/ml). Reduction in FPG (DeltaFPG) after
troglitazone treatment were correlated with reduction in HOMA-R (DeltaHOMA-R) (r=0.721, P<0.0001). DeltaFPG was correlated with serum
leptin (r=0.441, P<0.01), HOMA-R (r=0.460, P<0.01) and FPG (r=-0.781, P<0.0001) at baseline, but not with BMI and serum IRI at baseline. Furthermore, serum
leptin at baseline was significantly correlated with DeltaHOMA-R (r=0.634, P<0.01).
Leptin concentration before treatment therefore, can be used as an predictor for clinical efficacy of
troglitazone in patients with
type 2 diabetes.