Lipid Accumulation Product Index and Triglyceride-Glucose Index as Predictors of Metabolic Syndrome in Young Adults: A Cross-Sectional Study

Abstract

Background: Metabolic syndrome (MetS) is a cluster of interrelated metabolic abnormalities comprising central obesity, insulin resistance, dyslipidaemia, hypertension, and impaired fasting glucose, collectively increasing the risk of type 2 diabetes mellitus, cardiovascular disease, and cerebrovascular disease. The Lipid Accumulation Product (LAP) index and the Triglyceride-Glucose (TyG) index have been proposed as simple, inexpensive surrogate markers of visceral adiposity and insulin resistance, respectively. However, head-to-head comparative data in Indian young adults are limited. Objectives: To evaluate and compare the diagnostic accuracy of the LAP index and the TyG index in predicting metabolic syndrome among young adults aged 20-40 years, and to correlate both indices with individual components of metabolic syndrome. Methods: This cross-sectional study enrolled 189 participants aged 20-40 years at SVMCH & RC, Puducherry from December 2025 to March 2026. Metabolic syndrome was defined per NCEP ATP III criteria with Asian waist circumference cut-offs. The LAP index was calculated as sex-specific formulae using waist circumference and serum triglycerides. The TyG index was calculated as Ln (fasting TG [mg/dL] x fasting glucose [mg/dL] / 2). ROC analysis was performed to derive optimal cut-off values. Results: The overall prevalence of metabolic syndrome was 27.5% (n=52). Both LAP (56.8 ± 12.5 vs. 28.4 ± 10.2, p<0.001) and TyG (9.1 ± 0.6 vs. 8.2 ± 0.5, p<0.001) indices were significantly elevated in the MetS group. ROC analysis revealed an AUC of 0.91 for the LAP index (sensitivity 85%, specificity 83%, cut-off 45.5) and 0.88 for the TyG index (sensitivity 82%, specificity 79%, cut-off 8.6). The LAP index showed stronger correlation with waist circumference (r=0.72) and triglycerides (r=0.81), while the TyG index correlated more strongly with fasting glucose (r=0.82). Conclusion : Both the LAP index and the TyG index are reliable, cost-effective surrogate tools for early identification of metabolic syndrome in young adults. The LAP index demonstrated marginally superior overall diagnostic accuracy. These indices merit integration into routine clinical practice for early metabolic risk stratification.