ABSTRACT
Recently, Nichalas Hales et al, have demonstrated that elevation of proinsulin levels predict morbidity and mortality with coronary artery disease in age above 27 years. Researchers found that an elevated level of proinsulin, but not insulin, was associated with about a two-fold increased risk of heart disease in nondiabetic men and women. Epidemiological studies have identified hyperproinsulinemia as an independent risk factor for the coronary artery disease [CAD]. In present study we evaluated the association of plasma proinsulin and insulin resistance [IR] with coronary artery disease [CAD] in non-diabetic subjects. Subjects: In this case control study, 41 Normrglycemia men with Angiographic evidence of CAD were compared with 41 control men matched for age and glycemia and with no history or evidence of cardiac diseases. Estimations of plasma glucose, lipids, fasting plasma specific insulin [SI] and proinsulin [PI] were performed. Insulin Resistance [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. Subjects with CAD had a higher body mass index [BMI] [25.4 +/- 4.3 vs. 22.9 +/- 3.2 kg/m2, P = 0.002] and a lower high-density lipoprotein [HDL] cholesterol level [17.5-21 Vs 19.8-23.4 mg/dl, P = 0.002]. They also had higher mean SI values [107.5 vs. 62.3 pmol/l, P = 0.002], P1 values [19.3 vs. 5.7 pmo, P < 0.0001], P1/SI ratios [21.4 vs. 10.3, P <0.00001] and HOMA IR [4.2 vs. 2.4, P = 0.004] compared with non-CAD subjects. These variables were associated with CAD in the unadjusted multiple regression analysis. In the multiple regression with the forward entry of the variables, P1 only showed independent association with CAD. Conclusions: Subjects with CAD had higher levels of obesity. CAD showed an association with low HDL cholesterol, circulating P P1/SI ratios and IR. So, Increased levels of proinsulin may predict an increased likelihood of coronary heart disease in men. Our finding suggests that proinsulin are useful for diagnosis of CAD in men. But this subject needs more researches