Features and clinical implications of fasting intact proinsulin to insulin molar (P/I) ratio 2: Analysis on the correlation between P/I ratio and each factor in the type 2 diabetes mellitus

We examined the characteristics of plasma intact proinsulin to insulin molar (P/I) ratio at fasting in the morning, using type 2 diabetic patients. P/I ratio showed a significant correlation with HOMA-β and Insulinogenic Index. In multivariate analysis, fasting plasma insulin was well associated with BMI, and intact proinsulin was associated with BMI and fasting plasma glucose. On the other hand, P/I ratio was associated with duration of diabetes in addition to the above. P/I ratio of the patients who were positive for family history showed significantly higher value than the non-family history group. Moreover, P/I ratio of the patients with diabetic complications showed significantly higher value than the non-complication group. Furthermore, P/I ratio of glibenclamide or glimepiride group, were significantly higher than that of the diet group. These results suggest that P/I ratio could be useful to understand pancreatic β cell dysfunction in type 2 diabetes mellitus, either for estimating the stage of diabetes or titrating the optimal drug therapy.