A cross-sectional study on anthropometric indices and hypertension in Chinese adults: comparison of discriminatory power and age-stratified analysis

Background Hypertension imposes a heavy public health burden in China. Simple anthropometric indicators help screen hypertension risk, yet the optimal index differs by age. This study compares five adiposity indices including WC, BMI, WHtR, ABSI, and BRI and their age-specific discriminatory ability among Chinese adults. Materials and methods In this cross-sectional analysis of 104,248 adults from a health check-up cohort in Southwest China, hypertension was defined as blood pressure ≥140/90 mmHg, a self-reported diagnosis, or current antihypertensive medication use. Multivariable logistic and linear regression models were employed to examine the associations between a one-standard-deviation increase in the Z-score of each index and hypertension prevalence or blood pressure levels. Discriminatory power was compared using the area under the receiver operating characteristic curve (AUC) overall and within age groups. Results Per standard deviation increase, WC, BMI, WHtR, ABSI, and BRI were associated with a 61% (OR 1.61, 95% CI: 1.58–1.64), 61% (1.61, 1.58–1.64), 60% (1.60, 1.57–1.63), 9% (1.09, 1.07–1.11), and 56% (1.56, 1.54–1.59) higher hypertension risk, respectively. WHtR and BRI showed the highest and identical AUC (both 0.676), followed by WC (0.653). ABSI had the lowest AUC (0.612). Discriminatory ability was strongest in adults aged 18–35 years, with WC performing best (AUC = 0.763). The associations for all indices significantly weakened with age ( P for interaction < 0.001). Conclusions WHtR and BRI demonstrated the strongest overall associations with hypertension, whereas WC was the best indicator in young adults. The performance of anthropometric indices varied by age, suggesting that age-specific considerations may enhance their utility for preliminary hypertension risk screening in practice.