Background and Objectives
Post transplantation anemia (PTA) is common among kidney transplant patients with a prevalence rate of 20-51% and is associated with increased graft loss and in most studies with increased mortality.
PTA could be early PTA, commonly defined as anemia during the first six months after transplantation or late PTA, defined as anemia that occurs more than six months after transplantation (prevalent in up to 36% of the population).
However, data on the effect of the severity of anemia on these associations is ambiguous. This study investigated the association between anemia severity and etiology and long-term prognosis.
Methodology
This study was a single-center retrospective cohort study, using the Rabin Medical Center (RMC) kidney transplant registry. The study methodology was as described in Table 1.
Key Results
Effect of anemia on Outcomes
Multivariate analysis demonstrated that anemia was significantly associated with the following outcomes:
In the early period:
Graft loss or mortality [hazard ratio (HR)=2.94, p<0.001]
All-cause mortality (HR=2.27, p=0.015)
Death censored graft loss (HR=3.14, p=0.001)
In the early period:
Death censored graft loss (HR=1.853, p=0.024)
Effect of Anemia severity on outcomes
The association between severe anemia and mortality remained significant in the multivariate analysis (HR=5.42, p<0.001).
Severe anemia was significantly associated with death censored graft survival, at both the early and late periods [HR=7.6, p<0.001 (for the early period) and HR=2.61, p=0.021 (for the late period)].
Effect of specific causes of anemia on outcomes
When death censored graft loss during the early period was evaluated, the following variables were found to be significantly associated with increased mortality:
Anemia due to acute kidney injury (AKI) (HR=4.49, p=0.002)
Anemia due to acute rejection (HR=4.27, p=0.001)
When all-cause mortality during the early period was evaluated, only anemia with AKI and acute rejection (HR=12.94, p<0.001) was found to be significantly associated with this outcome.
Conclusion
PTA is associated with graft loss and mortality especially during the first three years. Anemia severity affects this association. An anemia workup is recommended for PTA.
Source: Schechter A, Gafter-Gvili A, Shepshelovich D, et al. BMC Nephrology. 2019;20:Article number 51.
