Relationship between anemia and clinic outcomes in maintenance hemodialysis patients

Objective To analysis the relationship between anemia and clinic outcomes retrospectively in maintenance hemodialysis patients for Renji Hospital, Shanghai Jiao Tong University School of Medicine, China. Methods This study enrolled all maintenance hemodialysis（MHD）patients between 1 January, 2007 and 31 December, 2014 at the Renji Hospital. They were followed up until death, cessation of hemodialysis, transfer to other centers or to the end of the study (31 December, 2014). Laboratory parameters, including hemoglobin concentrations, transferrin saturation, ferritin, serum albumin, were measured every 3 months. According to the Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines, the patients were divided into target-hemoglobin group (110≤Hb ≤120 g/L) and non target-hemoglobin group ( 120 g/L), and then the compliance rate of Hb, Ferritin, transferrin saturation, and the influence factors of compliance rate of Hb as well as its relationship with the prognosis were analyzed. Results Total 517 maintenance hemodialysis patients were involved in this study. The mean age was (63.76±14.78) years and 59.96% patients were male. Only 35.20%, 91.26% and 31.18% of them met the K/DOQI defined targets for hemoglobin, transferrin saturation and ferritin levels. The average levels of TSAT and Ferritin had no significant difference between the target-hemoglobin group and the non target-hemoglobin group. Compared with patients in non target-hemoglobin group, the target-hemoglobin group had significantly higher qualified rate of transferrin saturation (94.97% vs 89.41%, P=0.045) and Ferritin (37.22% vs 28.13%, P=0.036). Multivariate logistic regression analysis showed that the serum albumin, blood intact parathyroid hormone (iPTH) and dialysis vintage were independent risk factors that affected whether hemoglobin was up to the target. Kaplan-Meier analysis showed that the 8-year survival rate and cardiovascular survival rate in target-hemoglobin group were obviously higher than that in the non target-hemoglobin group (86.70% vs 75.30%, χ2Log rank=7.134, P=0.008; 93.80% vs 85.30%, χ2Log rank=6.134, P=0.013, respectively). Dialysis frequency, age and ferritin were independent risk factors of all-cause mortality for non target-hemoglobin group, and Dialysis frequency was independent risk factors of cardio-cerebral vascular disease mortality for non target-hemoglobin group. Conclusions The compliance rate of hemoglobin in MHD patients is still not steady controlled. Blood iPTH, serum albumin and dialysis vintage are independent risk factors that affect whether hemoglobin is up to the target in MHD patients. Sub-standard hemoglobin increases both all-cause mortality and cardio-cerebral vascular disease mortality in MHD patients.