The association between CALLY index and obesity in adolescents: a comparative analysis with traditional inflammatory markers

OBJECTIVE: To investigate the association between the C-reactive protein-Albumin-lymphocyte (CALLY) index and obesity in adolescents, and evaluate its predictive performance compared to traditional inflammatory markers. METHODS: ) and discrimination were evaluated, with sensitivity analyses for model specifications. RESULTS: The CALLY index was inversely associated with obesity (OR = 0.968, 95% CI 0.958-0.977, p < 0.001), with each 1-unit increase reducing obesity odds by 3.20%. This association remained significant after multivariate adjustment and varied by age, race, and physical activity. The standalone AUC of CALLY (0.743) significantly outperformed traditional markers (PLR: 0.515, NLR: 0.546, SII: 0.593, SIRI: 0.598). Combined with covariates, AUC increased to 0.774 (DeLong test p < 0.001). At the cutoff of 15.10, CALLY achieved > 80% sensitivity with a positive likelihood ratio near 2.0. CONCLUSIONS: The CALLY index is a robust and independent predictor of obesity in adolescents, outperforming traditional inflammatory markers. Its integration with traditional covariates further enhances predictive accuracy, suggesting that the CALLY index could be a valuable tool for early screening and intervention in adolescent obesity.