Healthcare resource use and clinical events associated with neutropenia among adult kidney transplant recipients receiving valganciclovir or ganciclovir prophylaxis: a matched case-control cohort study.

Background: Cytomegalovirus prophylaxis with valganciclovir and ganciclovir is associated with increased neutropenia risk in kidney transplant recipients. This study assessed the association between neutropenia and short-term healthcare resource utilization (HCRU) and clinical events for adults receiving valganciclovir and/or ganciclovir prophylaxis post-kidney transplantation in the United States.

Methods: Adult kidney transplant recipients from 2012 to 2020 who received valganciclovir and/or ganciclovir prophylaxis were identified in the TriNetX database. Patients with a neutropenia event during the 1-year post-kidney transplant were identified as cases and those without were identified as controls. Cases and controls were matched 1:1 on patient characteristics in the 1-year period before the kidney transplant. HCRU and clinical event rates in the year following the first neutropenia event were compared between the cases and controls.

Results: Of 3564 identified case-control pairs, the average age was 52 years and 59.57% were male. Cases had higher HCRU in the first year after neutropenia than controls, characterized by 1.40-, 1.28-, and 1.33-times higher rates of inpatient, outpatient, and emergency department visits (all p < 0.001). Cases also had higher incident rates for cytomegalovirus-related events, use of granulocyte colony stimulating factor, and opportunistic infections (all adjusted incident rate ratios >1 with p < 0.01), and greater risks of death, graft loss, and acute graft rejection (all adjusted hazard ratios >1 with p < 0.001).

Conclusion: Higher HCRU and clinical burden were observed within the first year following post-transplant neutropenia. New options for cytomegalovirus prophylaxis that are less likely to induce neutropenia are needed to improve patient outcomes.