Sex- and metabolic-specific association between cumulative body mass index and incident chronic kidney disease: A prospective community-based cohort study

Background and aim

Difference in metabolic status may cause inconsistent association between body mass index (BMI) and chronic kidney disease (CKD) in men and women. This study aimed to quantify sex-specific association between cumulative BMI (cumBMI) and incident CKD by different metabolic status.

Methods and results

Participants free of CKD from the Kailuan Study were followed biennially from baseline (June 2006 to October 2007) to December 2019. cumBMI was calculated by use of follow-up BMI and follow-up time and was divided into low weight (<18.5 kg/m²), normal weight (18.5–23.9 kg/m²), overweight (24–27.9 kg/m²), and obesity (≥28 kg/m²) according to Chinese criteria. Metabolic health was defined as the absence of hypertension, dyslipidemia, and diabetes at baseline. CKD was defined as having estimated glomerular filtration rate <60 mL/min/1.73 m². This study included 76984 participants, with a mean age of 50.0 ± 11.6 years and 80.0 % of men. Overweight (HR = 1.24, 95 % CI: 1.16–1.31) and obesity (HR = 1.94, 95 % CI: 1.77–2.12) were associated with higher risk of incident CKD in men regardless of metabolic status. Corresponding population attributable risk percentages for overweight and obesity were 10.3 % (95%CI: 7.1–12.9) and 12.7 % (95%CI: 10.6–14.7), respectively. However, low weight (HR = 1.56, 95 % CI: 1.05–2.30) and obesity (HR = 1.32, 95 % CI: 1.01–1.73) were associated with higher risk of incident CKD in metabolically healthy women but not in metabolically unhealthy women.

Conclusions

This study demonstrated sex- and metabolic-specific associations between BMI and CKD occurrence and advocates an individualized weight management strategy.