White blood cells as a novel mortality predictor in haemodialysis patients

Background. Many conventional cardiovascular risk factors in the general population are not as predictive in end‐stage renal disease (ESRD). As absolute neutrophil count and total white blood cell (WBC) count are associated with adverse cardiovascular outcomes and all‐cause mortality, this analysis was undertaken to explore the associations of WBC variables with mortality risk in ESRD. Methods. Of a total study population of 44 114 ESRD patients receiving haemodialysis during 1998 at facilities operated by Fresenius Medical Care, North America, 25 661 patients who underwent differential white cell count and had complete follow‐up were included. Information on case mix (age, gender, race), clinical (diabetes, body mass index), and laboratory variables (haematocrit, albumin, creatinine, potassium, calcium, phosphorus, bicarbonate, ferritin, transferrin saturation and differential WBC count) was obtained. Associations between lymphocyte count, neutrophil count and demographic and clinical variables were examined using linear regression. Associations between WBC variables and survival were estimated using Cox proportional hazard regression. Results. A higher lymphocyte count was associated with higher serum albumin and creatinine, lower age and black race. High neutrophil count was associated with lower serum albumin and creatinine, younger age and white race (all Ps