A new approach for diagnosing type 1 diabetes in autoantibody-positive individuals based on prediction and natural history.

Sosenko JM, Skyler JS, DiMeglio LA, Beam CA, Krischer JP, Greenbaum CJ, Boulware D, Rafkin LE, Matheson D, Herold KC, Mahon J, Palmer JP, Type 1 Diabetes TrialNet Study Group, Diabetes Prevention Trial-Type 1 Study Group
Diabetes Care. 2015 38 (2): 271-6

PMID: 25519451 · PMCID: PMC4302258 · DOI:10.2337/dc14-1813

OBJECTIVE - We assessed whether type 1 diabetes (T1D) can be diagnosed earlier using a new approach based on prediction and natural history in autoantibody-positive individuals.

RESEARCH DESIGN AND METHODS - Diabetes Prevention Trial-Type 1 (DPT-1) and TrialNet Natural History Study (TNNHS) participants were studied. A metabolic index, the T1D Diagnostic Index60 (Index60), was developed from 2-h oral glucose tolerance tests (OGTTs) using the log fasting C-peptide, 60-min C-peptide, and 60-min glucose. OGTTs with Index60 ≥2.00 and 2-h glucose <200 mg/dL (Ind60+Only) were compared with Index60 <2.00 and 2-h glucose ≥200 mg/dL (2hglu+Only) OGTTs as criteria for T1D. Individuals were assessed for C-peptide loss from the first Ind60+Only OGTT to diagnosis.

RESULTS - Areas under receiver operating characteristic curves were significantly higher for Index60 than for the 2-h glucose (P < 0.001 for both DPT-1 and the TNNHS). As a diagnostic criterion, sensitivity was higher for Ind60+Only than for 2hglu+Only (0.44 vs. 0.15 in DPT-1; 0.26 vs. 0.17 in the TNNHS) OGTTs. Specificity was somewhat higher for 2hglu+Only OGTTs in DPT-1 (0.97 vs. 0.91) but equivalent in the TNNHS (0.98 for both). Positive and negative predictive values were higher for Ind60+Only OGTTs in both studies. Postchallenge C-peptide levels declined significantly at each OGTT time point from the first Ind60+Only OGTT to the time of standard diagnosis (range -22 to -34% in DPT-1 and -14 to -27% in the TNNHS). C-peptide and glucose patterns differed markedly between Ind60+Only and 2hglu+Only OGTTs.

CONCLUSIONS - An approach based on prediction and natural history appears to have utility for diagnosing T1D.

© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

MeSH Terms (15)

Adult Autoantibodies Biological Assay Blood Glucose C-Peptide Diabetes Mellitus, Type 1 Early Diagnosis Epidemiologic Methods Fasting Female Glucose Tolerance Test Humans Male Middle Aged ROC Curve

Connections (2)

This publication is referenced by other Labnodes entities: