title: A low lymphocyte percentage is a predictor of mortality and hospitalization in hemodialysis patients.
abstract: OBJECTIVE
  Lymphocyte percentage (LYM%), an independently measured value to reflect peripheral lymphocyte count and a possible nutritional marker, may be related to clinical outcome in maintenance dialysis (MHD) patients.
  
  
  METHODS
  We examined the associations of the baseline white blood cell count (WBC) and LYM% with 12-month mortality and three measures of hospitalization in a cohort of 1,283 MHD patients from 10 outpatient DaVita dialysis clinics in Los Angeles County, as well as in a subcohort of 372 MHD patients with additional measures of inflammation, nutrition and comorbidity. Multi-variate Cox and Poisson models that included 13 co-variates including case-mix features, dialysis dose, blood hemoglobin and serum albumin were explored.
  
  
  RESULTS
  Patients, aged 57.8 +/- 15.2 years, included 49% men and 49% diabetics. Baseline WBC was 7,353 +/- 2.427 per microl, and LYM% was 21.2 +/- 7.3%. LYM% had significant correlations with "malnutrition-inflammation score" and inverse correlations with serum interleukin-6. The WBC and LYM% had significant but opposite predicting values for mortality and hospitalization, indicating that a high WBC and a low LYM% were each independently associated with increased mortality. After dividing each variable into four quartiles, only the highest WBC quartile (> or = 8,500) but not the other middle two quartiles, predicted increased mortality. However, all three lower quartiles of LYM% vs. the highest quartile (based on quartile cutoffs of 16%, 20.3% and 25.5%) were significantly and progressively associated with greater risks of mortality and hospitalizations. The absolute lymphocyte count (LYM% times WBC/100) exhibited somewhat similar trends but its outcome predictability was not as strong as LYM%.
  
  
  CONCLUSIONS
  A high WBC and a low LYM% are associated with significant increase in mortality and hospitalization in MHD patients. Lymphocyte percentage, compared to absolute lymphocyte count, appears to be a better nutritional and anti-inflammatory marker and a more sensitive predictor of mortality and hospitalization in MHD patients.
authors.affiliation: Division of Nephrology and Hypertension, Research and Education Institute, Harbor-UCLA Medical Center, Torrance, CA 90509-2910, USA.
authors.forename: N
authors.initials: N
authors.lastname: Kuwae
authors.forename: J D
authors.initials: JD
authors.lastname: Kopple
authors.forename: K
authors.initials: K
authors.lastname: Kalantar-Zadeh
mesh_terms: D015415:Biomarkers; D005260:Female; D006760:Hospitalization; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D007676:Kidney Failure, Chronic / Q000097:blood / Q000401:mortality* / Q000628:therapy; D007958:Leukocyte Count; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D006435:Renal Dialysis
chemical_list: D015415:Biomarkers; D015850:Interleukin-6