Anthropometry-adjusted TyG indices improve insulin resistance estimation: an exploratory euglycemic-hyperinsulinemic clamp study in Japanese adults without diabetes.
Level 4 - case-series / case-control
Cross-sectional diagnostic validation study comparing surrogate indices against a reference standard in a single cohort
PubMed 41948418 · doi:10.1007/s13340-026-00883-9
What was done
Researchers evaluated the diagnostic accuracy of anthropometry-adjusted triglyceride-glucose (TyG) indices against the gold-standard euglycemic-hyperinsulinemic clamp (EHC) in 61 Japanese adults without diabetes. Insulin resistance (IR) was defined as an insulin sensitivity index (ISI) below the 25th percentile. They compared surrogate markers—HOMA-IR, the original TyG index, TyG-BMI, TyG-waist circumference (TyG-WC), and TyG-waist-to-height ratio (TyG-WHtR)—using Spearman's rank correlations, receiver operating characteristic (ROC) curves, and pairwise DeLong tests.
What was found
TyG-BMI and TyG-WHtR correlated more strongly with clamp-derived ISI (ρ = -0.544 and ρ = -0.546, respectively) than HOMA-IR or unadjusted TyG. For identifying clamp-defined IR, TyG-BMI achieved an area under the curve (AUC) of 0.810 (optimal cutoff 203.7) and TyG-WHtR achieved an AUC of 0.829, outperforming conventional markers on DeLong testing. The optimal cutoff for HOMA-IR was approximately 2.5.
Why it matters
Incorporating simple anthropometric measures (BMI or waist-to-height ratio) into the TyG index improves surrogate estimation of insulin resistance when hyperinsulinemic clamp testing is not feasible.
Limits
The study had a very small sample size (n = 61) and evaluated only Japanese adults without diabetes, limiting generalizability to other ethnic groups and individuals with established diabetes. IR was defined using an arbitrary internal cohort distribution cutoff (bottom 25th percentile of ISI). Exact numerical values and confidence intervals for several indices (such as unadjusted TyG AUC) were not provided in the abstract.
Cited by
- supports The euglycemic hyperinsulinemic clamp is the gold standard for measuring insulin resistance.