Sex- and Age-Specific Associations of Triglyceride-Glucose Index with Impaired Renal Function: A Cross-Sectional Study.

Purpose: Triglyceride-glucose (TyG) index, a surrogate marker of insulin resistance, has emerged as a potential predictor of cardiovascular and metabolic diseases. However, its relationship with renal function impairment (RFI) and the influence of age and sex remain unclear. This study aimed to investigate the association between the TyG index and RFI in a large Chinese adult population and to evaluate its potential as an independent risk marker across sex and age groups. Patients and Methods: We conducted a cross-sectional study involving 21,224 adults aged 16-93 years who underwent health examinations at a tertiary hospital in China. Anthropometric and laboratory data were collected. RFI was defined as an estimated glomerular filtration rate of <60 mL/min/1.73 m Results: The overall prevalence of RFI was 23.5% with a higher prevalence observed in men than in women. Higher TyG index quartiles were associated with increased body mass index (BMI), mean arterial pressure (MAP), triglyceride, fasting glucose, and RFI prevalence. After adjustment for BMI and MAP, the TyG index remained significantly associated with RFI only in females aged ≥50 years (adjusted odds ratio for Q4 vs Q1: 1.603, 95% confidence interval: 1.313-1.957, p < 0.001). Conclusion: An elevated TyG index was independently associated with RFI in older women. Owing to its simplicity and cost-effectiveness, TyG index may be a useful tool for early screening of renal risk, particularly among postmenopausal women. Nonetheless, longitudinal studies are needed to confirm a causal relationship.