Decreased Beta Cell Function and Insulin Sensitivity Contributed to Coronary Artery Disease in Patients with Normal Glucose Tolerance

AIM: To investigate the association among insulin sensitivity, insulin secretion, beta cell function and coronary artery disease (CAD) in patients with normal glucose tolerance. METHODS: One hundred eighty-nine patients with normal glucose tolerance (NGT) participated in this study and underwent coronary angiography. We estimated the severity of CAD by counting the number of diseased vessels and Gensini score using coronary angiography. The HOMA-IR index and Matsuda index were used to estimate insulin sensitivity. Insulin secretion was assessed using the HOMA-β index, insulinogenic index and AUC-insulin/glucose. Beta cell function was assessed using the basal disposition index, early-phase disposition index and total disposition index. We finally determined the relationship between CAD and these indices. RESULTS: There were statistically significant differences in the HOMA-IR, Matsuda index, basal disposition index, early-phase disposition index and total disposition index both in the single- and multiple-diseased vessel groups when compared to the 0-diseased vessel group; however, there was no significant difference between the single- and multiple- diseased vessel groups. Moreover, HOMA-β, the insulinogenic index and AUC-ins/glu showed no significant difference among the three groups. Multivariate logistic regression analysis suggested that the HOMA-IR, Matsuda index, early-phase disposition index and total disposition index were independent risk factors for the presence of CAD. CONCLUSION: Insulin resistance and beta cell function were closely related to the incidence of CAD in patients with normal glucose tolerance.