RESUMO
BACKGROUND: It has not been clearly established whether insulin resistance/deficiency leads directly to atherogenesis or through its association with other risk factors such as lipoprotein(a) [Lp(a)]. OBJECTIVE: This project aimed at studying the association between basal insulin, lipids and lipoprotein(a) levels in patients with type 2 diabetes mellitus. METHODS: Fasting blood samples were analyzed for Insulin, Lipoprotein(a), total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), glucose and glycosylated hemoglobin (HbA1c) levels in 60 patients with type 2 Diabetes Mellitus (DM) and 28 healthy subjects. We divided patients into two groups based on basal insulin levels: > or = 10 microIU/ml and < 10 microIU/ml. RESULTS: Insulin levels were higher in diabetic versus control individuals [p < 0.05]. TC (p< 0.01), LDL-C (p< 0.05), TC/HDL ratio (p< 0.01) and TG levels (p< 0.05) were higher and HDL- C levels were significantly lower (p < 0.001) in both diabetic groups as compared to control. Lp(a) levels were significantly higher in both diabetic groups, when compared to the control group. Lp(a) levels were significantly lower in diabetics with basal insulin > or =10 microIU/ml when compared to those with basal insulin < 10 microIU/ml (p < 0.05). Regression analysis revealed a significant relationship of Lp(a) with insulin levels (r = 0.262, p < 0.05) and Insulin Glucose ratio (r = 0.257, p < 0.05). CONCLUSION: Lp(a) levels correlate inversely with insulin levels in Type 2 diabetic patients. Lp(a) may be one of the cardiovascular risk factor in type 2 diabetic patients with longer duration of DM.