Preservation of β-cell function in autoantibody-positive youth with diabetes

CJ Greenbaum, AM Anderson, LM Dolan… - Diabetes …, 2009 - Am Diabetes Assoc
CJ Greenbaum, AM Anderson, LM Dolan, EJ Mayer-Davis, D Dabelea, G Imperatore…
Diabetes care, 2009Am Diabetes Assoc
OBJECTIVE To determine the extent of β-cell function in youth with diabetes and GAD65
and/or IA2 autoantibodies. RESEARCH DESIGN AND METHODS Fasting C-peptide levels
from 2,789 GAD65-and/or IA2 autoantibody-positive youth aged 1–23 years from the
SEARCH for Diabetes in Youth study were used. Preserved β-cell function was defined on
the basis of cut points derived from the Diabetes Control and Complications Trial
(DCCT)(fasting C-peptide≥ 0.23 ng/ml) and from the US adolescent population of the …
OBJECTIVE
To determine the extent of β-cell function in youth with diabetes and GAD65 and/or IA2 autoantibodies.
RESEARCH DESIGN AND METHODS
Fasting C-peptide levels from 2,789 GAD65- and/or IA2 autoantibody-positive youth aged 1–23 years from the SEARCH for Diabetes in Youth study were used. Preserved β-cell function was defined on the basis of cut points derived from the Diabetes Control and Complications Trial (DCCT) (fasting C-peptide ≥0.23 ng/ml) and from the U.S. adolescent population of the National Health and Nutrition Examination Survey (NHANES) 5th percentile for fasting C-peptide (≥1.0 ng/ml). We compared the clinical characteristics between those with and without preserved β-cell function.
RESULTS
Within the first year of diagnosis, 82.9% of youth had a fasting C-peptide ≥0.23 ng/ml and 31.2% had values ≥1.0 ng/ml. Among those with ≥5 years of diabetes duration, 10.7% had preserved β-cell function based on the DCCT cutoff and 1.0% were above the 5th percentile of the NHANES population.
CONCLUSIONS
Within the 1st year of diagnosis, four of five youth with autoantibody-positive diabetes have clinically significant amounts of residual β-cell function and about one-third have fasting C-peptide levels above the 5th percentile of a healthy adolescent population. Even 5 years after diagnosis, 1 of 10 has fasting C-peptide above a clinically significant threshold. These findings have implications for clinical classification of youth with diabetes as well as clinical trials aimed to preserve β-cell function after diabetes onset.
Am Diabetes Assoc