Association between weight-adjusted waist index and new-onset hyperuricemia: a national prospective cohort study in Chinese adults

OBJECTIVE: This study aimed to explore the relationship between weight-adjusted waist index (WWI) and new-onset hyperuricemia, and to examine any possible effect modifiers among the middle-aged and elderly Chinese individuals. METHODS: We analyzed data from 6,250 participants in the China Health and Retirement Longitudinal Study (CHARLS). WWI was calculated using waist circumference divided by the square root of body weight. The study's primary outcome was the incidence of hyperuricemia, identified by serum uric acid levels ≥417 μmol/L in men and ≥357 μmol/L in women during the final assessment. RESULTS: During a median follow-up of 4 years, 550 participants (8.8%) developed hyperuricemia. A significant positive correlation existed between WWI and the risk of hyperuricemia [odds ratio (OR) per unit increase: 1.18; 95% confidence interval (CI): 1.08-1.30]. The risk was notably higher in the upper tertiles of WWI distribution compared to the lowest (Tertile 2: OR: 1.32, 95% CI: 1.04-1.68; Tertile 3: OR: 1.87, 95% CI: 1.45-2.42). Additionally, participants with hemoglobin A1c (HbA1c) levels ≥5.7% exhibited a stronger link between WWI and hyperuricemia risk (OR per unit increase: 1.48; 95% CI: 1.07-2.04) than those with HbA1c <5.7% (OR: 1.31; 95% CI: 1.02-1.69; P for interaction = 0.01). WWI did not exhibit better predictive ability compared with BMI and WC in the results of ROC curve. CONCLUSIONS: Our findings suggest that higher WWI values are independently associated with an increased risk of hyperuricemia, with a particularly strong association in those with elevated HbA1c levels. However, its predictive capability was not superior to conventional anthropometric indices.