Choice of Acid Suppressant Therapy and Long-Term Graft Outcomes After Kidney Transplantation

Study Objective: The purpose of this study was to comprehensively evaluate the long-term adverse effects of proton pump inhibitors (PPIs) compared with histamine-2 receptor antagonists (H2RAs) in kidney transplant recipients. Methods: This retrospective cohort compared 582 patients treated with PPI with 705 patients treated with H2RA and evaluated adverse effects throughout their course of acid suppressant therapy to a maximum of nine years posttransplant. The primary outcome of interest was renal function at 1 year posttransplant; secondary outcomes included renal function at 30 days, 3, 5, and 9 years posttransplant as well as rejection, electrolyte and laboratory abnormalities, osteoporosis, pneumonia, and Clostridium difficile infections. Results: Renal function did not significantly differ at any timepoint posttransplant. Rejection rates and Clostridium difficile infections were similar between groups; osteoporosis and pneumonia rates were numerically higher in the PPI treated arm but did not reach statistical significance. Proton pump inhibitor (PPI) treated patients were more likely to experience hypomagnesemia requiring supplementation. High dose PPI treated patients had significantly higher rates of pneumonia and osteoporosis compared with H2RA treated patients. Patients were maintained on PPI therapy for an average of 5 years and H2RA therapy for 3 years posttransplant, the majority without a clear indication for therapy. Conclusions: There was no difference in renal function, rejection, or graft loss between PPI and H2RA treated patients. The majority of patients were maintained on PPI therapy for several years posttransplant without a clear indication; critical evaluation of ongoing need for acid suppressant therapy in the posttransplant course should be an area of future focus.