Weight-adjusted waist index as a practical predictor for diabetes, cardiovascular disease, and non-accidental mortality risk.

BACKGROUND AND AIM: Identifying a more suitable marker among various measures of adiposity, demonstrating strong associations and predictive ability for clinical use, remains a topic of debate. Weight-adjusted waist index (WWI) has been proposed as a novel index of adiposity, yet its exploration is limited, especially in Chinese populations. This study seeks to examine the associations between body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHTR), weight-adjusted waist index (WWI), waist circumference divided by body mass to the power of 0.333 (WC/M0.333), visceral adiposity index (VAI), lipid accumulation product (LAP), and the incidence of diabetes, cardiovascular disease, and non-accidental mortality in Chinese populations. Furthermore, our goal is to compare the respective predictive values of these measures for these health outcomes.

METHODS AND RESULTS: This prospective cohort study included 21,750 subjects with a 9-year follow-up period. Cox proportional hazard models were used to investigate the relationship between eight anthropometric indexes and the incidence of diabetes, cardiovascular disease, and non-accidental mortality. The predictive value of these eight indexes was compared using the area under the curve metric. Significant positive associations were found between WWI and the risk of diabetes. Using the first quartile (Q1) of WWI as the reference group, hazard ratios with 95% confidence intervals for the risk of diabetes were 1.58 (0.98-2.55) for Q2, 2.18 (1.34-3.35) for Q3, and 2.27 (1.41-3.67) for Q4. Significant associations were observed with the highest quartile of WWI for the risk of cardiovascular disease [Q2: HR 1.45 (95% CI 1.06-1.98); Q3: 1.33 (0.97-1.83); Q4: 1.55 (1.13-2.14)] and risk of non-accidental mortality [Q2: 0.94 (0.80-1.11); Q3: 1.24 (1.04-1.48); Q4: 1.44 (1.16-1.79)]. Receiver operating characteristic analysis revealed that WWI exhibited superior discrimination and accuracy in predicting cardiovascular disease and non-accidental mortality compared to other adiposity indexes (BMI, WC, WHR, WHTR, WC/M0.333, VAI, and LAP).

CONCLUSION: WWI exhibited the most robust and consistent association with the incidence of cardiovascular disease and non-accidental mortality. Given its simplicity and widespread use, WWI emerges as a novel and practical predictor of diabetes, cardiovascular disease, and non-accidental mortality among the eight adiposity indexes investigated in this study.