Validation of the Diabetes Prevention Trial-Type 1 Risk Score in the TrialNet Natural History Study

Abstract

Objective: We assessed the accuracy of the Diabetes Prevention Trial-Type 1 Risk Score (DPTRS), developed from the Diabetes Prevention Trial-Type 1 (DPT-1), in the TrialNet Natural History Study (TNNHS).

Research design and methods: Prediction accuracy of the DPTRS was assessed with receiver-operating characteristic curve areas. The type 1 diabetes cumulative incidence within the DPTRS intervals was compared between the TNNHS and DPT-1 cohorts.

Results: Receiver-operating characteristic curve areas for the DPTRS were substantial in the TNNHS (P < 0.001 at both 2 and 3 years). The type 1 diabetes cumulative incidence did not differ significantly between the TNNHS and DPT-1 cohorts within DPTRS intervals. In the TNNHS, 2-year and 3-year risks were low for DPTRS intervals <6.50 (<0.10 and <0.20, respectively). Thresholds ≥7.50 were indicative of high risk in both cohorts (2-year risks: 0.49 in the TNNHS and 0.51 in DPT-1).

Conclusions: The DPTRS is an accurate and robust predictor of type 1 diabetes in autoantibody-positive populations.

Figure 1

Plots of the observed type 1 diabetes risks at 2 years (A) and 3 years (B) according to DPTRS intervals are shown for the DPT-1 and TNNHS cohorts. The risks were derived from type 1 diabetes cumulative incidence curves for DPT-1 and the TNNHS within each of the intervals. There were no significant differences at 2 years and 3 years between the DPT-1 and TNNHS cumulative incidence curves within any of the intervals.