The association between peripheral eosinophil count and chronic kidney disease: evidence from NHANES 1999–2018

Background Renal impairment has been previously linked to peripheral eosinophil count (PEC), prompting an investigation into its potential relationship with chronic kidney disease (CKD). This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES 1999–2018) to comprehensively explore the association between PEC and CKD.Methods Survey-weighted generalized multivariate linear regression was employed to evaluate the associations between PEC, urinary albumin-to-creatinine ratio (UACR), and estimated glomerular filtration rate (eGFR), with meticulous adjustment for potential covariates. To assess non-linear correlations, a restricted cubic spline analysis was conducted. Sensitivity analysis was performed to test the stability of results.Results The study included a total of 9224 participants with non-dialysis CKD. In the multivariate linear regression model, after comprehensive adjustment for potential covariates, PEC showed a negative association with eGFR (β per 100 cells/uL increase in PEC, −0.71; 95% CI, −1.04, −0.37), while demonstrating a positive trend with UACR (β per 100 cells/uL increase in PEC, 10.21; 95% CI, 1.37, 19.06). The restrictive cubic spline curve analysis suggested that these associations occurred within the range of 0 to 400 cells/uL for PEC. Sensitivity analysis supported the stability of the observed results.Conclusions Circulating eosinophil levels are negatively correlated with eGFR and demonstrate a positive trend with UACR, when PEC falls within the range of less than 400 cells/uL among adults with CKD. Further research is warranted to validate these findings.