Physical Activity and the Development of Islet Autoimmunity and Type 1 Diabetes in 5-15 Year Old Children Followed in the TEDDY Study

Objective: This study investigated physical activity and its association with the development of islet autoimmunity (IA) and type 1 diabetes in genetically at-risk 5-15 year old children. Research Design and Methods: As part of the longitudinal Environmental Determinants of Diabetes in the Young (TEDDY) study, annual assessment of activity using accelerometry was conducted from age 5. Time-to-event analyses using Cox proportional hazard models were used to assess the association between time spent in moderate-to-vigorous physical activity per day and the appearance of one or several autoantibodies and progression to type 1 diabetes in three risk groups: 1) 3869 IA negative children of whom 157 became single IA positive; 2) 302 single IA positive children of whom 73 became multiple IA positive; 3) 294 multiple IA positive children of whom 148 developed type 1 diabetes. Results: No significant association was found in risk group 1 or risk group 2. A significant association was seen in risk group 3 (HR = 0.920, 95% CI 0.856, 0.988 per 10 minutes, p = 0.021), particularly when GADA was the first autoantibody (HR = 0.883, 95% CI 0.783, 0.996 per 10 minutes, p=0.043). Conclusions: More daily minutes spent in moderate-to-vigorous physical activity was associated with a reduced risk of progression to type 1 diabetes in 5-15 year old children who had developed multiple islet autoantibodies.