Abstract: Objective A retrospective study of hemoglobin variability in maintenance hemodialysis (MHD) patients to understand the relationship between hemoglobin variability and prognosis. Methods Patients newly initia between Jan 1, 2009 and May 31, 2013 were enrolled in this study. They were followed up until May 31, 2015. According to their hemoglobin levels throughout the 12 months observation period after they entered hemodialysis, they were classified into three hemoglobin variability groups: the rise type group, the wave type group, and the continuous low type group. Results This retrospective study was conducted in
205 patients newly treated with hemodialysis with the mean age of 60.45±13.26 years old. At the time of dialysis initiation, hemoglobin level was 92.60 ± 16.35 g/L, and hemoglobin level ≥110 g/L was found in 33 (16.10%) patients. Sixty-two patients were hospitalized during the follow-up period, and the cause of hospitalization was cardiovascular disease (CVD) in 41 (66.13%) patients. Thirty-nine died during the follow-up period, and 27 (69.23%) of them died of CVD. Multivariate Cox regression analysis showed that the hemoglobin variability of wave type and continuous low type were the risk factors for all-cause and CVD hospitalization; age and the hemoglobin variability of wave type and continuous low type were the risk factors for all-cause and CVD mortality. The risk of all-cause mortality in the continuous low type patients was 3.502 times higher that in the rise type patients (95%CI 1.293~9.485, P=0.014), while the risk of all-cause hospitalization was also higher in the continuous low type patients than in the rise type patients (RR=3.639, 95% CI 1.778~7.451, P＜0.001). The continuous low type patients had a higher risk of CVD mortality (RR=4.759, 95% CI 1.357~ 16.689, P=0.015) and CVD hospitalization (RR=8.424, 95% CI 2.511~28.259, P=0.001). Conclusions Correction of anemia and maintenance of a stable hemoglobin level can prolong survival time and reduce the
risks of all-cause and CVD hospitalization in MHD patients.

Key words: Maintenance hemodialysis, Hemoglobin variability, Cardiovascular disease, Prognosis