title: Post-renal transplantation anemia at 12 months: prevalence, risk factors, and impact on clinical outcomes.
abstract: OBJECTIVE
  To investigate any association between post-transplantation anemia (PTA) and clinical outcomes following living donor kidney transplantation.
  
  
  METHODS
  We retrospectively evaluated 887 patients who received living donor kidney transplantations at our medical center between January 2006 and December 2012 to evaluate whether PTA, defined as serum hemoglobin (Hb) levels of <130 g/l in men and <120 g/l in women, at 12 months is associated with post-transplant outcomes, including graft function, death-censored graft survival, or patient survival.
  
  
  RESULTS
  The prevalence of PTA at 1, 3, 6, and 12 months was 84.3, 39.5, 26.2, and 21.6 %, respectively. Donor age [hazard ratio (HR), 1.03; 95 % confidence interval (CI) 1.01-1.05] and acute rejection (HR 2.13; 95 % CI 1.28-3.54) were found to be independent risk factors for PTA at 12 months. Recipient age (HR 0.98; 95 % CI 0.95-1.00), pre-transplantation Hb levels (HR 0.99; 95 % CI 0.98-1.00), and estimated glomerular filtration rates (eGFRs) at 12 months (HR 0.96; 95 % CI 0.94-0.97) were found to confer slight protection against PTA at 12 months. PTA at 12 months was associated with increased graft loss (HR 1.046; 95 % CI 1.045-1.046). For each increase in anemia degree, there was a 2.77-fold greater risk of graft loss (HR 2.77; 95 % CI 1.50-5.13). When stratified according to eGFR, PTA was found to be a predictor of graft loss in patients with an eGFR of <60 ml/min/1.73 m(2) (HR 4.57; 95 % CI 1.98-10.56) but not in patients with an eGFR of >60 ml/min/1.73 m(2) (HR 1.89; 95 % CI 0.13-27.78). PTA was not found to be a predictor of patient survival.
  
  
  CONCLUSIONS
  Anemia is common after kidney transplantation, and its prevalence declines with time after transplantation. Presence of anemia at 12 months post-transplant was an independent predictor of graft loss, with higher risk of graft loss in patients with anemia and poorer kidney functions.
authors.affiliation: Department of Urology, West China Hospital, Sichuan University, Guoxue Xiang #37, Chengdu, 610041, Sichuan, People's Republic of China.
authors.forename: Zhongli
authors.initials: Z
authors.lastname: Huang
authors.forename: Turun
authors.initials: T
authors.lastname: Song
authors.forename: Lei
authors.initials: L
authors.lastname: Fu
authors.forename: Zhengsheng
authors.initials: Z
authors.lastname: Rao
authors.forename: Dongyang
authors.initials: D
authors.lastname: Zeng
authors.forename: Yang
authors.initials: Y
authors.lastname: Qiu
authors.forename: Xianding
authors.initials: X
authors.lastname: Wang
authors.forename: Libo
authors.initials: L
authors.lastname: Xie
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wei
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Tao
authors.initials: T
authors.lastname: Lin
mesh_terms: D000328:Adult; D000740:Anemia / Q000453:epidemiology* / Q000209:etiology; D002681:China / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006085:Graft Survival; D006801:Humans; D007676:Kidney Failure, Chronic / Q000401:mortality / Q000601:surgery*; D016030:Kidney Transplantation / Q000009:adverse effects*; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D015995:Prevalence; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D013997:Time Factors