Longitudinal Assessment of Pancreas Volume by MRI Predicts Progression to Stage 3 Type 1 Diabetes

Objective This multicenter prospective cohort study compared pancreas volume as assessed by MRI, metabolic scores derived from oral glucose tolerance testing (OGTT), and a combination of pancreas volume and metabolic scores for predicting progression to Stage 3 type 1 diabetes (T1D) in individuals with multiple diabetes-related autoantibodies. Research Design and Methods Pancreas MRI were performed in 65 multiple autoantibody-positive participants enrolled in the Type 1 Diabetes TrialNet Pathway to Prevention study. Prediction of progression to Stage 3 T1D was assessed using pancreas volume index, OGTT-derived Index60 and Diabetes Prevention Trial-Type 1 Risk Score (DPTRS) scores, as well as a combination of pancreas volume index and DPTRS. Results Pancreas volume index, Index60, and DPTRS were all significantly different at study entry in 11 individuals who subsequently progressed to Stage 3 T1D compared with 54 participants who did not progress (p < 0.005). Pancreas volume indexdid not correlate with metabolic testing across individual study participants. Pancreas volume index declined longitudinally in the 11 individuals diagnosed with Stage 3 T1D, while Index60 and DPTRS increased. The area under the receiver operating curve for predicting progression to Stage 3 from measurements at study entry was 0.76 for pancreas volume index, 0.79 for Index60, 0.79 for DPTRS, and 0.91 for pancreas volume index and DPTRS. Conclusions These findings suggest that measures of pancreas volume and metabolism reflect distinct components of risk for developing Stage 3 type 1 diabetes and that combining these measures may provide superior prediction than either alone.