THE EFFECT OF OBESITY ON FIBRINOLYTIC-ACTIVITY AND PLASMA-LIPOPROTEIN (A) LEVELS IN PATIENTS WITH TYPE-2 DIABETES-MELLITUS IN KOREA

To determine whether previously reported abnormalities in fibrinolytic activity and plasma lipoprotein (a) levels could reflect obesity rather than diabetes per se, plasma concentrations of tissue-type plasminogen activator (t-PA), type 1 plasminogen activator inhibitor (PAI-I), and lipoprotein (a) (Lp (a)) were investigated in sixty-four type 2 diabetic patients (56.1 +/- 9.5 years; body mass index, 24.6 +/- 3.3 kg/m(2)) and thirty-two control subjects (57.9 +/- 8.9 years; body mass index, 24.6 +/- 3.4 kg/m(2)). Both the plasma t-PA and PAI-I antigen levels were similar between the diabetic group (10.6 +/- 3.8 ng/ml; 27.7 +/- 11.6 ng/ml) and the control group (12.2 +/- 3.5 ng/ml; 27.7 +/- 9.6 ng/ml). The PAI-I levels were evenly distributed from 5.93 to 52.7 ng/ml in diabetic patients. The difference of Lp (a) levels between the two groups was negligible (the diabetic group, median 11 mg/dl (range 0-72 mg/dl); the control group, median 13 mg/dl (range 0-55 mg/dl)). Significant correlations between PAI-1 levels and body mass index (BMI) were observed in both groups. In the diabetic group, PAI-1 levels also correlated with fasting C-peptide levels (r = 0.54, P < 0.01) and serum triglyceride levels (r = 0.28, P < 0.05). However, we could not find a significant association between either t-PA or PAI-1 levels and Lp (a) levels in the diabetic and control groups. Stepwise forward regression analysis using BMI, fasting C-peptide levels, ages, systolic blood pressures, HbA(1c), triglycerides, t-PA and PAI-1 levels as independent variables showed that only the fasting C-peptide levels correlated with PAI-1 levels (F = 5.61, P < 0.05). These results suggest that the patients with type 2 diabetes do not seem to have lower fibrinolysis or higher Lp (a) levels than the controls with comparable age and BMI. It may not be the diabetes per se but the combined obesity that appeared to cause hypofibrinolysis and dyslipidemia in the diabetic patients.