Abstract
Objective: The weight-adjusted waist circumference index (WWI) is a more robust indicator of visceral obesity than body mass index (BMI). Cross-sectional studies have demonstrated an association between the WWI and an increased incidence of chronic kidney disease (CKD). However, longitudinal evidence to support this relationship is neither conclusive nor sufficient. This study aimed to prospectively evaluate the relationship between the WWI and CKD.
Methods: This was a prospective cohort study of 10200 community residents aged ≥ 45 years without CKD who were recruited from the Chinese Healthand Longevity Longitudinal Study (CHARLS) and who were followed for up to 8.0 years. Both men and women were categorized into four groups based on the sex-specific quartile of the WWI at the time of inclusion in the trial. CKD was based on self-reported physiciandiagnoses. The relationship between the WWI and CKD occurrence was analyzed through log-rank tests and survival curves before using nonrestricted cubic splines. Finally, we performed a sensitivity analysis to check the robustness of our findings.
Results: In total, 4809 men and 5391 women were included in the trial, with an average age of 67.43 ± 9.55 years. A total of 723 patients were diagnosed with CKD during the 8-year follow-up period. The prevalence of CKD in each group was 5.86%, 4.89%, 6.16%, and 6.83%, respectively, in the female subgroup. After adjusting for covariates, the hazard ratio (HR) (95% CI) in the lowest quartile was 1.56 (1.04 - 2.34), that in the third quartile was 1.59 (1.08 - 2.34), and that in the highest quartile was 1.53 (1.01 - 2.31) compared to that in the second quartile. However, in the male subgroup, the prevalence of CKD in each group was 8.80%, 8.51%, 7.85%, and 8.37%, respectively. After adjusting for various variables, the incidence of CKD did not significantly differ among the groups (P>0.05).
Conclusion: In summary, this study showed that the WWI is significantly linked to the risk of CKD in women, even after adjusting for covariates. This finding underscores the important role of weight management in the prevention and treatment of CKD among the female population. Thus, the adoption of measures to control central obesity among the female population is essential for preventing CKD.