Serum C-peptide levels as a predictor of beta-cell function in children with type 1 diabetes

Abbas Abed Khazaal; Miami Kadhim Yousif; Ahmed Jaafar Hendi; Dhaighum Imad Atwan

Abbas Abed Khazaal Department of Pediatrics, College of Medicine, University of Basrah, Basrah, Iraq
Miami Kadhim Yousif Department of Pediatrics, Al-Zahraa Medical College, University of Basrah, Basrah, Iraq https://orcid.org/0000-0003-2500-596X
Ahmed Jaafar Hendi Department of Pediatrics, Al-Zahraa Medical College, University of Basrah, Basrah, Iraq
Dhaighum Imad Atwan Department of Pediatrics, Al-Zahraa Medical College, University of Basrah, Basrah, Iraq

Keywords: autoantibodies, B-cell function, control group, thyrotropin

Abstract

C-peptide levels are important for assessing residual insulin secretion from β cells in individuals with Type 1 diabetes (T1DM). This study aimed to evaluate serum C-peptide levels in pediatric patients with T1DM and correlate them with various clinical and laboratory parameters. In a case-control study, 80 children aged 2–15 years with T1DM were enrolled, and an additional 80 non-diabetic healthy children were included as a control group. Laboratory data encompassed plasma glucose, C-peptide, hemoglobin A1c (HbA1c), pancreatic autoantibodies (anti-GAD), Thyrotropin, and Tissue transglutaminase antibodies-IgA (Anti-TTG-IgA). We conducted correlation analyses between C-peptide levels and clinical/laboratory parameters among children with T1DM. The chi-square test was employed, with a significance threshold set at p≤0.05. The mean age at diagnosis of T1DM was 8.11 years, with a mean disease duration of 3.84 years. The average HbA1c level was 10.94%. Twenty-seven out of eighty patients had a positive family history of diabetes, and the average GAD antibody level was 118.128 IU/ml. Serum C-peptide levels in children with T1DM were significantly lower than those in non-diabetic children (0.189 ng/ml vs. 2.960 ng/ml, respectively), indicative of reduced residual B-cell function. Correlation analyses revealed associations between C-peptide levels and age at diagnosis, disease duration, BMI, and fasting blood sugar, but not with HbA1c or anti-GAD levels. Patients with lower C-peptide levels tended to be diagnosed at a younger age and had a longer mean disease duration. Fasting C-peptide levels are valuable indicators for predicting beta-cell function in pediatric T1DM patients. Early initiation of treatment may be essential to preserve pancreatic beta-cell function.