{"doi":"10.1210/clinem/dgac285","title":"Oral Glucose Tolerance Test Measures of First-phase Insulin Response and Their Predictive Ability for Type 1 Diabetes","abstract":"CONTEXT: Decreased first-phase insulin response (FPIR) during intravenous glucose tolerance testing (IVGTT) is an early indicator of β-cell dysfunction and predictor of type 1 diabetes (T1D). OBJECTIVE: Assess whether oral glucose tolerance test (OGTT) measures could serve as FPIR alternatives in their ability to predict T1D in autoantibody positive (Aab+) subjects. DESIGN: OGTT and IVGTT were performed within 30 days of each other. Eleven OGTT variables were evaluated for (1) correlation with FPIR and (2) T1D prediction. SETTING: Type 1 Diabetes TrialNet \"Oral Insulin for Prevention of Diabetes in Relatives at Risk for T1D\" (TN-07) and Diabetes Prevention Trial-Type 1 Diabetes (DPT-1) studies clinical sites. PATIENTS: TN-07 (n = 292; age 9.4 ± 6.1 years) and DPT-1 (n = 194; age 15.1 ± 10.0 years) Aab + relatives of T1D individuals. MAIN OUTCOME MEASURES: (1) Correlation coefficients of OGTT measures with FPIR and (2) T1D prediction at 2 years using area under receiver operating characteristic (ROCAUC) curves. RESULTS: Index60 showed the strongest correlation in DPT-1 (r = -0.562) but was weaker in TN-07 (r = -0.378). C-peptide index consistently showed good correlation with FPIR across studies (TN-07, r = 0.583; DPT-1, r = 0.544; P < 0.0001). Index60 and C-peptide index had the highest ROCAUCs for T1D prediction (0.778 vs 0.717 in TN-07 and 0.763 vs 0.721 in DPT-1, respectively; P = NS), followed by FPIR (0.707 in TN-07; 0.628 in DPT-1). CONCLUSIONS: C-peptide index was the strongest measure to correlate with FPIR in both studies. Index60 and C-peptide index had the highest predictive accuracy for T1D and were comparable. OGTTs could be considered instead of IVGTTs for subject stratification in T1D prevention trials.","journal":"The Journal of Clinical Endocrinology & Metabolism","year":2022,"id":272700,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":11,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9547,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":766368,"name":"Megan Warnock","orcid":null,"position":1,"is_corresponding":false},{"id":39913,"name":"Ping Xu","orcid":"0000-0003-1599-7408","position":2,"is_corresponding":false},{"id":421207,"name":"Susan Geyer","orcid":null,"position":3,"is_corresponding":false},{"id":513352,"name":"Jennifer B. Marks","orcid":"0000-0002-4551-7332","position":4,"is_corresponding":false},{"id":513353,"name":"Antoinette Moran","orcid":"0000-0002-2694-5147","position":5,"is_corresponding":false},{"id":512512,"name":"Jay M. Sosenko","orcid":"0000-0002-7204-8367","position":6,"is_corresponding":false},{"id":7388,"name":"Carmella Evans‐Molina","orcid":"0000-0001-7764-8663","position":7,"is_corresponding":false},{"id":336605,"name":"David A. Baidal","orcid":"0000-0001-7694-3265","position":0,"is_corresponding":true}],"reference_count":25,"raw_metadata":null,"created_at":"2026-07-19T00:27:47.926496Z","pmid":"35524749","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}