The Impact of Hemoglobin Levels on Patient and Graft Survival in Renal Transplant Recipients

BACKGROUND: It remains unclear whether low hemoglobin levels are associated with increased mortality or graft loss after renal transplantation. This study assessed the relationship of hemoglobin levels with patient and graft survival in 3859 patients with functioning renal transplants more than 6-months posttransplantation. METHODS: Detailed data was prospectively collected as part of the pharmacovigilance Long Term Efficacy and Safety Surveillance project. RESULTS: Lower hemoglobin levels were associated with graft loss on multivariate analysis adjusted for demographic characteristics, comorbidity, and biochemical variables; lower hemoglobin was associated with mortality on univariate, but not adjusted analysis; hemoglobin variability was associated with mortality and graft loss on univariate, but not multivariate analysis. Older recipient age, lower serum albumin, raised urea, increased comorbidity (Charlson Index), and angiotensin-converting enzyme inhibitor (ACEi)/angiotensin II receptor blocker (ARB) non-use were also associated with mortality. Younger recipients, male recipients and those with lower serum albumin, lower body mass index, higher systolic blood pressure, and impaired allograft function experienced higher graft failure rates. CONCLUSIONS: This study suggests that full correction of hemoglobin levels to improve mortality in renal transplant recipients is unjustified; further study is required to assess the effect of hemoglobin correction in delaying graft failure. It also highlights other nonimmunologic risk factors for adverse outcomes in renal transplant recipients.