Residual C-peptide in patients with Type 1 diabetes and multiethnic backgrounds

OBJECTIVE: To evaluate serum C-peptide in 88 patients from a multiethnic population with Type-1 diabetes and variable disease durations. METHOD: Eighty-eight patients with a mean disease duration of 8.1+/-7.6 years were included and underwent C-peptide measurement before and after glucagon stimulation. Chi-squared and Mann Whitney U-tests were used to compare the variables between groups (all two-tailed, alpha = 0.05). Spearmans correlation coefficient was used to test the association between the continuous variables. Logistic regression was used for the multivariate analysis. Twenty-eight (31.8%) individuals had significantly detectable C-peptide levels after stimuli, particularly those with a shorter disease duration (p<0.001). RESULTS: Patients with detectable C-peptide levels required lower insulin doses (p<0.009) and had similar HbA1C results (p = 0.182) and fewer chronic complications (p = 0.029). CONCLUSION: C-peptide detection was common in Type-1 diabetics, particularly shortly after being diagnosed. This result may have clinical implications.