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Diabetes autoantibodies do not predict progression to diabetes in adults: the Diabetes Prevention Program
1Department of Epidemiology, University of Colorado at Denver, Colorado School of Public Health, Aurora, CO, USA.
Aims:
To determine if the presence of diabetes autoantibodies predicts the development of diabetes among participants in the Diabetes Prevention Program.
Methods:
A total of 3050 participants were randomized into three treatment groups: intensive lifestyle intervention, metformin and placebo. Glutamic acid decarboxylase (GAD) 65 autoantibodies and insulinoma-associated-2 autoantibodies were measured at baseline and participants were followed for 3.2 years for the development of diabetes.
Results:
The overall prevalence of GAD autoantibodies was 4.0%, and it varied across racial/ethnic groups from 2.4% among Asian-Pacific Islanders to 7.0% among non-Hispanic black people. There were no significant differences in BMI or metabolic variables (glucose, insulin, HbA(1c), estimated insulin resistance, corrected insulin response) stratified by baseline GAD antibody status. GAD autoantibody positivity did not predict diabetes overall (adjusted hazard ratio 0.98; 95% CI 0.56-1.73) or in any of the three treatment groups. Insulinoma-associated-2 autoantibodies were positive in only one participant (0.033%).
Conclusions:
These data suggest that 'diabetes autoimmunity', as reflected by GAD antibodies and insulinoma-associated-2 autoantibodies, in middle-aged individuals at risk for diabetes is not a clinically relevant risk factor for progression to diabetes.
Insights
Diabetes autoantibodies, such as GAD autoantibodies, do not predict diabetes development in at-risk middle-aged adults. This finding suggests diabetes autoimmunity is not a significant risk factor for progression to diabetes.
Area of Science:
- Endocrinology
- Immunology
- Diabetes Research
Background:
- Diabetes Prevention Program (DPP) investigated interventions to prevent type 2 diabetes.
- Autoimmunity plays a role in type 1 diabetes, but its role in type 2 diabetes progression is less clear.
- Glutamic acid decarboxylase (GAD) 65 autoantibodies are markers of autoimmune diabetes.
Purpose of the Study:
- To assess if diabetes autoantibodies predict diabetes development in DPP participants.
- To evaluate the association between GAD 65 autoantibodies and insulinoma-associated-2 autoantibodies with diabetes incidence.
Main Methods:
- 3050 participants randomized into lifestyle, metformin, or placebo groups.
- Baseline measurement of GAD 65 and insulinoma-associated-2 autoantibodies.
- Follow-up for an average of 3.2 years for diabetes development.
Main Results:
- GAD autoantibodies were present in 4.0% of participants, with variations across racial/ethnic groups.
- GAD autoantibody positivity did not predict overall diabetes development (aHR 0.98; 95% CI 0.56-1.73).
- Insulinoma-associated-2 autoantibodies were rare (0.033%).
Conclusions:
- Diabetes autoimmunity, indicated by GAD and insulinoma-associated-2 autoantibodies, is not a clinically relevant risk factor for diabetes progression in at-risk middle-aged individuals.
- These findings do not support routine screening for these autoantibodies in this population for predicting diabetes risk.
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Type II Diabetes II: Pathophysiology

