Post-transplantation erythrocytosis in kidney transplant recipients—A retrospective cohort study

Objectives: To characterize risk factors for the development of post-transplant erythrocytosis (PTE), and its long-term effect on mortality, graft failure, and thrombosis. Methods: Retrospective study including all kidney transplant recipients in Rabin Medical Center (RMC) during the years 2005-2014. The primary outcome was a composite outcome of all-cause mortality or graft failure at the end of follow-up. Secondary outcomes included death censored graft loss, venous thromboembolism, major adverse cardiovascular events, and mortality. A matched control group was also evaluated. Univariate and multivariate time-varying Cox model analyses were conducted for outcome evaluation. Results: A total of 1304 patients were included, 169 of whom were diagnosed with PTE (12.9%). PTE was associated with male gender, higher glomerular filtration rate (GFR), and polycystic kidney disease. PTE was found to be associated with a reduced risk of the primary outcome (HR 0.355, CI 95% 0.151-0.89, P =.027) in a univariate time-varying Cox analysis, but was not associated with the composite outcome in a multivariate analysis. There was no difference in the primary outcome when the PTE group was compared with the matched control. Conclusion: PTE was not found to be associated with long-term outcomes of graft failure and poor survival.