Association between absolute blood eosinophil count and CKD stages among cardiac patients

Elevated eosinophil count was shown to be associated with the development of cholesterol embolization syndrome, a potentially life-threatening condition, after catheter-based procedures. We investigated the association between stages of chronic kidney disease (CKD) and the absolute eosinophil count (AEC) among cardiac patients. CKD stages were determined solely on the estimated glomerular filtration rate or requirement for hemodialysis. Eosinophilia is defined as an eosinophil count exceeding 500/μL. A total of 1022 patients were enrolled in the current study, and eosinophil counts (/μL) in the first through fourth eosinophil count quartiles were <88, 88 to 154, 155 to <238, and 238 ≤, respectively, and 29 patients (2.8 %) had eosinophilia. Correlation coefficient between the AEC and age was -0.188 (P = 0.001) in women and -0.042 (n.s.) in men (by Spearman's correlation test). Patients with higher CKD stages had a higher prevalence of the highest AEC quartile or eosinophilia. Logistic regression analysis using severe renal dysfunction (i.e., CKD stage 4 or 5) as the dependent variable, the highest AEC quartile had a significant positive association with an odds ratio of 1.99 (95 % confidence interval, 1.20-3.31, P < 0.01) after adjustment for sex, age, systolic blood pressure, and total white blood cell count. Similarly, after adjustment for the same variables, eosinophilia was associated with severe renal dysfunction with an odds ratio of 2.60 (95 % confidence interval, 1.08-6.26, P < 0.05). Eosinophil count was positively associated with higher CKD stages among cardiology patients, some fraction of which might be related to subclinical cholesterol embolization.