Background and aim: C-peptide is an important indicator of endogenous insulin release. Our aim was to investigate the association of serum C-peptide levels with age, BMI and insulin doses in newly diagnosed type 1 diabetic (DM1) children.
Metods: The patients with newly diagnosed DM1 were enrolled the study and classified as DM1A and DM1B. Clinical and laboratory findings of all the patients were recorded. Daily insulin doses, BMI and its z score were calculated. Fasting and two hours after the meal serum samples were obtained for C-peptide levels. The statistical analyses were performed using the SPSS.
Results: Although serum C-peptide levels of DM1B patients were higher (fasting and postprandial 0.53±0.80 and 0.98±1.29 ng/ml, respectively) than those of DM1A patients (fasting and postprandial 0.41±0.39 ng/ml, 0.43±0.36 ng/ml, respectively), we found only significant difference in postprandial C-peptide levels between the groups (P <0.05). There was a significant positive correlation between both fasting and postprandial C-peptide levels and age, BMI, and BMI z score (P<0.001). There was no significant correlation between serum C-peptide levels and insulin doses.
Conclusions: C-peptide levels might be affected by body fat and age as well as pancreatic beta-cell function. It is known that body fat is to be related to insulin resistance. However, there are only a few studies evaluating the effect of BMI on C-peptide levels in children with DM1. We found a strong correlation between serum C-peptide levels and BMI and its z score. Therefore, it is important to evaluate serum C-peptide levels according to age and BMI while performing clinical assessment and differential diagnosis.
27 - 29 Sep 2018
European Society for Paediatric Endocrinology