title: Hemoglobin variability does not predict mortality in peritoneal dialysis patients.
abstract: BACKGROUND
  Hemoglobin variability in hemodialysis patients treated with erythropoiesis-stimulating agents has been used to evaluate mortality and comorbidity. Different outcomes have been reported in American and European hemodialysis patients. There are, however, few studies of the effects of hemoglobin variability in peritoneal dialysis patients.
  
  
  METHODS
  We investigated hemoglobin variability in 363 peritoneal dialysis patients over 2 years to evaluate mortality and the association with comorbidity, peritonitis, and hospitalization. The hemoglobin of all patients selected for the study had been monitored for at least 6 months (April 2008 to September 2008). We assessed hemoglobin variability as fluctuations from the target hemoglobin level (11-12.5 g/dL). We defined the following 6 patient groups on the basis of hemoglobin patterns: consistently low (< 11 g/dL), consistently target range (11-12.5 g/dL), consistently high (> 12.5 g/dL), low-amplitude fluctuation with low hemoglobin levels, low-amplitude fluctuation with high hemoglobin levels, and high amplitude fluctuation.
  
  
  RESULTS
  Only 2% of patients maintained a stable hemoglobin level within the target range and 46.8% of patients exhibited consistently low hemoglobin levels. After 2 years of observation, there was no difference in mortality as assessed by Kaplan-Meier analysis. There were also no differences in peritonitis and hospitalization between the 6 groups. However, the length of hospital stay was longer in the high amplitude fluctuation group (p = 0.008).
  
  
  CONCLUSIONS
  Hemoglobin variability does not predict mortality in peritoneal dialysis patients.
authors.affiliation: Department of Nephrology, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyun, Taiwan.
authors.forename: Ho-Ching
authors.initials: HC
authors.lastname: Chen
authors.forename: Kuan-Hsing
authors.initials: KH
authors.lastname: Chen
authors.forename: Yu-Jr
authors.initials: YJ
authors.lastname: Lin
authors.forename: Chee-Jen
authors.initials: CJ
authors.lastname: Chang
authors.forename: Ya-Chung
authors.initials: YC
authors.lastname: Tian
authors.forename: Chih-Wei
authors.initials: CW
authors.lastname: Yang
authors.forename: Cheng-Chieh
authors.initials: CC
authors.lastname: Hung
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006454:Hemoglobins / Q000378:metabolism*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000401:mortality*; D012189:Retrospective Studies
chemical_list: D006454:Hemoglobins