Identification of Peripheral Blood Endotypes Associated With Age in Pediatric Type 1 Diabetes.

Aims: This study aimed to identify age-related peripheral immune endotypes in pediatric patients with type 1 diabetes (T1D) at disease onset and assess their metabolic control 1 year post-diagnosis. Methods: Immune cell subpopulations (T and B lymphocytes, myeloid cells, and natural killer NK cells) were analyzed via multicolor flow cytometry in pediatric T1D patients and age- and sex-matched controls, grouped as 12 years. Sociodemographic, clinical, and metabolic data were collected, including autoantibodies, bicarbonate (HCO3), C-peptide, HbA1c, and time in range (TIR), with follow-up for 1 year to evaluate partial remission (PR) likelihood and metabolic control. Results: Patients 12 years, while anti-glutamic acid decarboxylase 65 (GAD65) positivity remained constant. Younger patients had lower PR rates and poorer glycemic control at 1 year. Conclusions: Younger patients face greater immune dysregulation and β-cell loss, while older patients show better immune maturity and metabolic outcomes. These differences underline the need for age-specific T1D therapies.