To investigate the hemoglobin (Hb) variability in maintenance hemodialysis patients, and analyze the influence factors on Hb fluctuation.

Patients undergoing maintenance hemodialysis for over 12 months in Zhongshan Hospital from June 2011 to December 2011 were enrolled. Target value of Hb was 110-120 g/L and hemoglobin fluctuation referred to the fluctuation in Hb ≥ 10 g/L between 2 continuous months. The influence factors on Hb fluctuation were evaluated with multivariate logistic regression analysis.

In 163 patients enrolled, the baseline Hb value was (107.52±15.47) g/L and the 6-month mean Hb was (106.57±15.22) g/L. The distributions of Hb were similar before and during the entire follow-up period. Among them, 46.6%-56.4% patients didn′t reach the Hb target range (Hb 110-120 g/L). Only 1.2% patients were always within the target range during the 6 months of follow-up. The average Hb variability was (8.15±5.01) g/L and the fluctuation ratio was 27.0%. Short-term fluctuations were common in the majority of hemodialysis patients, but a few patients were with chronic Hb instability. The dialysis age and the basal Hb values of the non-fluctuation group were significantly higher than those of the fluctuation group (t=-5.602, P=0.048; t=-1.731, P=0.010), and the erythropoietin (EPO) dose was significantly lower than that of the fluctuation group (t=6.218, P< 0.001). Multivariate logistic regression analysis showed that, after adjustment by dialysis age<24 months and basic Hb<100 g/L, the EPO dose≥200 U/kg/w) remained significantly and independently associated with the Hb variability in patients with maintenance hemodialysis (OR=4.7, 95% CI 3.2-9.3, P=0.030).

Hemoglobin fluctuation is common in patients with maintenance hemodialysis and a few patients are with chronic Hb instability. Patients with substantial Hb fluctuation during maintenance hemodialysis need to use greater doses of EPO.