Endocrine Abstracts

JOINT2937

Background: New biomarkers are needed to assess prognosis and metabolic control at the time of diagnosis in pediatric patients with type 1 diabetes (T1D). Studies in adults with type 2 diabetes showed that patients with a low postprandial c-ceptide/glucose ratio had worse metabolic control. However, there is a lack of knowledge on this biomarker ratio in children with T1D. We aimed to investigate the relationship between the c-peptide/glucose ratio (CGR) at the diagnosis time and short- or long-term metabolic control in T1D.

Materials and Methods: We included children diagnosed with T1D between 2013 and 2019, who had measured pre-treatment c-peptide and glucose levels, and were followed up for 3-5 years. Relevant data were obtained from medical records retrospectively. Results are presented as mean ± standard deviation or median (25-75th percentile) based on the normality of distribution.

Results: The study was conducted with 97 patients (54. 6% female, age 8. 9 ± 3. 8 years). Of these, 46. 4% (n = 45) were diagnosed with diabetic ketoacidosis (DKA) and 44. 3% (n = 43) with diabetic ketosis. At the diagnosis, serum glucose was 446 (303-537) mg/dL, c-peptide was 0. 36 (0. 2-0. 6) ng/mL, insulin was 2. 9 IU/mL (1. 7-4. 0 IU/mL; n = 88), and HbA1c was 11. 6±1. 8%. During the follow-up, 31 patients (32%) observed the honeymoon period for a median of 15 (7-21) months. The CGR (x1000) at the diagnosis was 0. 80 (0. 48-1. 54), and the insulin/glucose ratio (x1000) was 62. 5 (35. 9-115. 9). The insulin/glucose ratio correlated positively with age, initial pH, HCO3, and c-peptide levels (P < 0. 05) and negatively with HbA1c in the first year of T1D (P = 0. 028). The CGR was positively correlated with age, pH, HCO3, and insulin levels at the first admission (P < 0. 001). Also, it was negatively correlated with the mean HbA1c in the first year after the diagnosis (P = 0. 031), but not with HbA1c in 2 to 5 years (p>0. 05). The ratio was higher in patients who had honeymoon period (1. 29 vs 0. 74; P = 0. 020). A CGR of >0. 46 predicted severe DKA (sensitivity: 83. 3%, specificity: 81. 4%, AUC=0. 795, P = 0. 002).

Conclusions: In this study, we found that the CGR in children with T1D can predict the presence and severity of DKA at the diagnosis, as well as metabolic control during and the first year. Also, it can be a useful marker to predict the honeymoon period. These results highlighted the importance of close monitoring and adjusting treatment plans of children with T1D who had lower c-peptide responses to hyperglycemia and reduced beta cell reserve at the diagnosis time.