Variability in hemoglobin levels: clinical implications. Case study of the anemic patient

A historical, prospective, multicenter, observational study was conducted on data from October 1996 to December 1997 to determine the impact of hemoglobin (Hb) variability on the interpretation of maintenance anemia management outcomes in hemodialysis patients. Trends in mean Hb levels were retrospectively analyzed to determine whether there were any differences between 1-month Hb averages versus 3- or 6-month rolling averages. Results showed that: (a) Hb measurements exhibit wide variability between patients and within patients, regardless of the assessment method used, and (b) it is difficult to maintain patients within the 1 g/dL Hb spread recommended by NKF-K/DOQI. The largest variations in Hb readings were observed in 1-month readings, while 6-month rolling averages exhibited the least variability. These data illustrate the importance of assessing long-term trends in laboratory data before making incremental or decremental modifications in the anemia prescription.