Proton pump inhibitor use after kidney transplantation and graft outcomes: A matched national cohort study.

This study evaluates the impact of proton pump inhibitor (PPI) use on graft-related outcomes following renal transplant. Proton pump inhibitors (PPIs) are frequently continued after kidney transplantation, often without a clear ongoing indication. Although their use has been associated with adverse renal outcomes in non-transplant populations, their clinical relevance in transplant recipients remains uncertain. We performed a retrospective cohort study using the TriNetX database of US health networks. We included 23,306 patients from 2000-2021 enrolled 4-6 weeks following their transplant. Patients were stratified by post-transplant PPI use and propensity score matched. The primary outcome was graft survival over 5 years; secondary outcomes included need for dialysis, renal function, and re-transplantation. Among 23,306 recipients, 15,601 patients (66.9%) were on PPI therapy 1 month post-transplant; 7553 matched pairs were analyzed. Post-transplant PPI use was associated with increased graft failure within 1 year (16.8% vs 9.4%; HR 1.79 [1.59-2.01]; P < .001) and between 1 and 5 years (12.8% vs 4.7%; HR 2.63 [2.27-3.05]; P < .001). Survival curves demonstrated early and sustained separation through 5 years (72.6% vs 85.8%; log-rank test P < .001). PPI exposure was also associated with increased dialysis dependence, progressive decline in graft function, and repeat transplantation, with greater risk observed with prolonged use (all P < .001). Post-transplant PPI use was common among kidney transplant recipients and was associated with a significantly increased risk of graft failure and worse kidney transplant outcomes. Persistent PPI use after kidney transplantation may represent a modifiable aspect of care, supporting periodic reassessment of acid suppression in transplant recipients.