Association of weight-adjusted-waist index with all-cause and cardiovascular mortality in China: A prospective cohort study

Abstract

Background and aims

As a new simple anthropometric index, the weight-adjusted-waist index (WWI) appears to be superior to body mass index (BMI) and waist circumference (WC) in assessing both muscle and fat mass. We aimed to explore the association of WWI with all-cause and cardiovascular mortality in southern China.

Methods and results

A total of 12,447 participants (mean age, 59.0 ± 13.3 years; 40.6% men) in Jiangxi Province from the China Hypertension Survey study were included. WWI was defined as WC divided by the square root of weight. The outcome was all-cause and cardiovascular mortality. During a median follow-up of 5.6 years, 838 all-cause deaths occurred, with 390 cardiovascular deaths. Overall, there was a nonlinear positive relationship of WWI with all-cause and cardiovascular mortality. Accordingly, compared with participants in quartiles 1–3 (<11.2 cm/√kg), a significant higher risk of all-cause mortality (HR: 1.36, 95% CI: 1.17, 1.58) and cardiovascular mortality (HR: 1.43, 95% CI: 1.15, 1.77) were found in quartile 4 (≥11.2 cm/√kg). Further adjustment for BMI and WC did not substantially alter the results. No significant interactions were found in any of the subgroups (sex, age, area, physical activity, current smoking, current alcohol drinking, hypertension, and stroke).

Conclusion

Higher WWI levels (≥11.2 cm/√kg) were associated with increased the risk of all-cause and cardiovascular mortality in southern China. These findings, if confirmed by further studies, suggested that WWI may serve as a simple and effective anthropometric index in clinical practice.