C-peptide and clinical presentation follow-up study in newly onset diabetes of the young

To evaluate the change of insulin secretary function of beta cells by measuring the follow-up C-peptide level in newly onset diabetes of the young in Korea, we examined, retrospectively, 65 patients aged between 15 and 35 years who were admitted within 1 year after the clinical onset and who had been followed-up for more than 2 years. According to the basal C-peptide level at the initial visit, patients were divided into three groups (G1, <0.6 ng/ml; G2, 0.6-1.0 ng/ml; and G3, >1.0 ng/ml). The clinical characteristics, laboratory parameters and follow-up basal C-peptide level were measured and the results obtained showed that BMI ((in G3 compared to G1 and G2) 23.1 +/- 4.7 vs. 17.6 +/- 1.5, 18.8 +/- 2.1, p < 0.01) and family history ((FH) 53 vs. 0%, 29%, p < 0.05) were significantly higher. In the follow-up measurement of basal C-peptide level, almost all patients (7/8) in G1 showed decreased basal C-peptide and these seven were classified as IDDM. In G2, 53% (9/17) of patients had a decreased follow-up basal C-peptide, and all of these nine patients except one were classified clinically as IDDM. In G3, 18% (7/40) of the patients had prominent deteriorations of the p cell function, and among these seven patients had a high ICA positivity (60%). So ICA might be a significant marker in predicting the secretary capacity of beta cell function in these patients. In conclusion, the follow-up of serum C-peptide level is a useful parameter for the classification of newly onset young diabetic patients.