Better HbA1c during the first years after diagnosis of type 1 diabetes is associated with residual C peptide 10 years later

Objective To identify the factors associated with residual C peptide production at least 10 years after diagnosis in children and adolescents with type 1 diabetes. Research design and methods 73 children and adolescents ( Results C peptide was detectable in 38% of participants. The C peptide concentration was 4.3±5.3 pmol/L. At onset of type 1 diabetes, participants were on average approximately 5 years of age, and their average HbA1c was 9.4% (79 mmol/mol). During the first 3 years after diagnosis, HbA1c was lower in the group with detectable C peptide at follow-up ≥10 years later. Moreover, detectable C peptide was more common among female participants. Body mass index SD scores had not increased since the 1-year follow-up, but were higher in patients with measurable C peptide. Nine participants (12%) had been diagnosed with celiac disease and two (3%) with hypothyreosis. Eighteen (25%) participants had retinopathy. Conclusions Children and adolescents with detectable C peptide after more than 10 years of diabetes duration were predominantly female and had better HbA1c than others during the first 3 years after diagnosis.