Ferrara, Christine T.Geyer, Susan M.Evans-Molina, CarmellaLibman, Ingrid M.Becker, Dorothy J.Wentworth, John M.Moran, AntoinetteGitelman, Stephen E.Redondo, Maria J.2019-06-042019-06-042017-12-01Ferrara, C. T., Geyer, S. M., Evans-Molina, C., Libman, I. M., Becker, D. J., Wentworth, J. M., … Type 1 Diabetes TrialNet Study Group (). The Role of Age and Excess Body Mass Index in Progression to Type 1 Diabetes in At-Risk Adults. The Journal of clinical endocrinology and metabolism, 102(12), 4596–4603. doi:10.1210/jc.2017-01490https://hdl.handle.net/1805/19526Background: Given the global rise in both type 1 diabetes incidence and obesity, the role of body mass index (BMI) on type 1 diabetes pathophysiology has gained great interest. Sustained excess BMI in pediatric participants of the TrialNet Pathway to Prevention (PTP) cohort increased risk for progression to type 1 diabetes, but the effects of age and obesity in adults remain largely unknown. Objective: To determine the effect of age and sustained obesity on the risk for type 1 diabetes in adult participants in the TrialNet PTP cohort (i.e., nondiabetic autoantibody-positive relatives of patients with type 1 diabetes). Research Design and Methods: Longitudinally accumulated BMI >25 kg/m2 was calculated to generate a cumulative excess BMI (ceBMI) for each participant, with ceBMI values ≥0 kg/m2 and ≥5 kg/m2 representing sustained overweight or obese status, respectively. Recursive partitioning analysis yielded sex- and age-specific thresholds for ceBMI that confer the greatest risk for type 1 diabetes progression. Results: In this cohort of 665 adults (age 20 to 50 years; median follow-up, 3.9 years), 49 participants developed type 1 diabetes. Age was an independent protective factor for type 1 diabetes progression (hazard ratio, 0.95; P = 0.008), with a threshold of >35 years that reduced risk for type 1 diabetes. In men age >35 years and women age <35 years, sustained obesity (ceBMI ≥5 kg/m2) increased the risk for type 1 diabetes. Conclusions: Age is an important factor for type 1 diabetes progression in adults and influences the impact of elevated BMI, indicating an interplay of excess weight, age, and sex in adult type 1 diabetes pathophysiology.en-USPublisher PolicyAgingAutoantibodiesBody Mass IndexDiabetes Mellitus -- Type 1Disease progressionInsulin antibodiesObesityArticle