BACKGROUND
Proinsulin is raised in people with NIDDM. Hyperproinsulinemia is thought to be a predictor for the subsequent development of NIDDM. We studied to investigate whether hyperproinsulinemia can predict the development of NIDDM in Korean subjects. METHOD: This study was performed as a nested case-control study. The case group was 67 newly developed diabetic patients out of 1193 initially non-diabetic cohott in Yonchon county. We have also selected 66 age-sex-B541-WHR matched control group who remain non-diabetic for 2 years. We compared baseline insulin, proinsulin and proinsulin/insulin ratio between two groups, RESULTS: There was no significant difference in baseline fasting insulin levels[46,77+/-17.3 vs 42.87+/- 11.6(pmol/L)] between converters to diabetes and non-converters. However, the baseline proinsulin levels in converters to diabetes were higher than those in non-converters.[16.07+/-14.3 vs 8.72+/-5.2(pmol/L)) The baseline proinsulin/imulin ratio in converters was also higher than those in non-converters. [0.30+/-0.17 vs 0.20+/-0.10] CONCLUSION: The results suggest that fasting hyper-proinsulinemia may be a predictor for subsequent development of NIDDM in Korean subjects.