Short and Long-Term Outcomes in Kidney Transplant Recipients with Neutropenia or Leukopenia Following CMV Prophylaxis

Background Neutropenia and leukopenia following kidney transplant are linked to poor transplant outcomes. One factor that can contribute to neutropenia or leukopenia following transplant is the use of valganciclovir as a cytomegalovirus prophylaxis. Objective This study aimed to evaluate post-transplant neutropenia and leukopenia and the associated resource use and costs among kidney transplant recipients receiving valganciclovir prophylaxis. Methods Adults receiving kidney transplant with a claim for valganciclovir 30 days post-transplant were included (Merative™ MarketScan® with Medicare supplemental database, January 2012–March 2021). Incidence of, and risk factors for, neutropenia and leukopenia were assessed 1 year post-transplant. Clinical outcomes, resource use, and costs were assessed through 5 years post-transplant. Results A total of 3121 and 357 individuals were included for the 1-year and 5-year analyses, respectively. Cumulative incidence of neutropenia or leukopenia 1 year post-transplant was 32.5%. Resource use was greater among patients with myelotoxicities than those without, driven by emergency department and inpatient visits. Among those with resource use, the total unadjusted median cost was greater in patients with vs without myelotoxicities ($82 536 vs $68 652 per patient per year, respectively; P < .0001). A greater proportion of those with myelotoxicities experienced clinical complications and resource use 2 to 5 years post-transplant. Conclusions Of kidney transplant recipients receiving valganciclovir prophylaxis, myelotoxicity claims were present in approximately one-third at 1 year post-transplant. Neutropenia or leukopenia in kidney transplant recipients is associated with high resource use and costs through 5 years post-transplant.