Combined triglyceride-glucose index and body mass index for early cardiovascular risk stratification in adults under 45: Findings from the Kailuan cohort.

BACKGROUND AND AIM: Early-onset cardiovascular disease (CVD) in adults aged<45 years represents an increasing global health challenge. We aimed to evaluate the potential effects of the triglyceride-glucose (TyG) index and body mass index (BMI) on CVD risk in young adults.

METHODS AND

RESULTS

We analyzed 65,291 CVD-free adults aged 18-44 years from the Kailuan Cohort (2006-2018). Participants were categorized by BMI (normal:<24 kg/m2; overweight:24-<28 kg/m2; obesity: ≥28 kg/m2) and TyG index (<8.45 vs ≥ 8.45). Cox proportional hazards models, interaction analyses, and ROC curves were applied. Over a median 7.2 years, 566 CVD events occurred. Obesity was associated with higher CVD risk regardless of TyG (obesity + TyG <8.45: HR = 1.55; 95%CI = 1.03-2.34; obesity + TyG ≥8.45: HR = 1.64; 95%CI = 1.23-2.18). Overweight participants showed increased risk only when TyG ≥8.45 (HR = 1.37; 95%CI = 1.05-1.79), whereas metabolically healthy overweight individuals (TyG <8.45) had no excess risk. Normal-weight participants with high TyG did not exhibit a significant risk increase (HR = 1.13; 95%CI = 0.84-1.53). No significant additive or multiplicative interaction between BMI and TyG was observed. Predictive performance improved when both measures were combined (0.623) compared with BMI (0.587) or TyG (0.601) alone (P < 0.001).

CONCLUSIONS

The combined assessment of TyG and BMI may facilitate early risk stratification and enhance risk awareness for CVD in adults aged<45 years. Obesity remains a high-risk phenotype regardless of metabolic status, whereas overweight confers increased risk only in metabolic dysfunction. This integrated approach supports a tiered prevention strategy: prioritizing weight management in obesity, targeting metabolic dysfunction in overweight individuals, and monitoring normal-weight individuals with elevated TyG for long-term risk.