Associations of serum bisphenol A levels with incident chronic kidney disease risk

Associations of bisphenol A (BPA) levels with renal disease are inconsistent. The present prospective study aims to evaluate the association of serum BPA levels with chronic kidney disease (CKD) in a Chinese middle-aged and elderly population. At baseline 1370 participants (mean age 61.7 years, 58.8% females) free of kidney disease and cancer were followed up nearly 10 years. Baseline serum BPA concentration was measured with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). Estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Multivariable logistic regression model was used to investigate relationship between serum BPA levels and incident CKD risk. During a 10-year follow-up, 246 individuals developed CKD. Baseline serum BPA concentration was 2.92 (1.00, 5.27) ng/mL. At baseline, after adjustment for multiple covariates serum BPA levels were negatively correlated with eGFR levels (β = -0.068, P = 0.009). Compared to those with low levels of serum BPA, participants with high levels had a significant negative association with CKD [ORs (95% CI) = 0.35 (0.25, 0.50), P < 0.001], and this association was not modified by conventional risk factors. The negative associations remained in females but not in males (P for interaction = 0.016). Significant interaction between baseline eGFR and serum BPA levels on CKD risk was also found (P for interaction = 0.027), Except subjects with 60-70 mL/min/1.73 m² eGFR at baseline, inverse association robustly existed between serum BPA levels and incident CKD risk in the other eGFR subgroups. Further studies are needed to validate our findings.