Association of proinsulin and insulin resistance with coronary artery disease in non-diabetic south Indian men

Aims To evaluate the association of plasma proinsulin and insulin resistanc e (IR) with coronary artery disease (CAD) in non-diabetic subjects. Methods In this case control study, 41 normoglycaemic men with angiographic evidence of CAD were compared with 41 control men matched for age and glyc aemia and with no history or evidence of cardiac diseases. Estimations of p lasma glucose, lipids, fasting plasma specific insulin (SI) and proinsulin (PI) were performed. IR was calculated by the homeostasis model assessment (HOMA) method. Multiple logistic regression analysis was performed to test the association of the variables with the prevalence of CAD. Results Subjects with CAD had a higher body mass index (BMI) (25.4 +/- 4.3 vs. 22.9 +/- 3.2 kg/m(2), P = 0.003) and waist to hip ratio (WHR) (0.95 +/- 0.05 vs. 0.89 +/- 0.09, P = 0.001) and a lower high-density lipoprotein (H DL) cholesterol level (0.97 +/- 0.2 vs. 1.1 +/- 0.2 mmol/l, P = 0.002). The y also had higher mean SI values (107.5 vs. 62.3 pmol/l, P = 0.002), PI val ues (19.3 vs. 5.7 pmol/l, P < 0.0001), PI/SI ratios (21.4 vs. 10.3, P < 0.0 001) and HOMA IR (4.2 vs. 2.4, P = 0.004) compared with non-CAD subjects. T hese variables were associated with CAD in the unadjusted multiple regressi on analysis. In the multiple regression with the forward entry of the varia bles, WHR and PI only showed independent association with CAD. Conclusions Subjects with CAD had higher levels of obesity and WHR. CAD sho wed an association with low HDL cholesterol, circulating PI, PI/SI ratios a nd IR.