Efficacy and safety of low-dose aspirin on preventing transplant renal artery stenosis: a prospective randomized controlled trial

Background:Transplant renal artery stenosis(TRAS)is a vascular complication after kidney transplantation associated with poor outcomes.This study aimed to analyze the efficacy and safety of low-dose aspirin for preventing TRAS.Methods:After kidney transplantation,patients were enrolled from January 2018 to December 2020 in Henan Provincial People’s Hospital.A total of 351 enrolled recipients were randomized to an aspirin group with low-dose intake of aspirin in addition to standard treatment(n=178),or a control group with only standard treatment(n=173).The patients was initially diagnosed as TRAS(id-TRAS)by Doppler ultrasound,and confirmed cases were diagnosed by DSA(c-TRAS).Results:In the aspirin and control groups,15.7%(28/178)and 22.0%(38/173)of the recipients developed id-TRAS,respectively,with no statistical difference.However,for c-TRAS,the difference of incidence and cumulative incidence was statistically significant.The incidence of c-TRAS was lower in the aspirin group compared with the control group(2.8%[5/178]vs.11.6%[20/173],P=0.001).Kaplan–Meier estimates and Cox regression model identified the cumulative incidence and hazard ratio(HR)of TRAS over time in two groups,showing that recipients treated with aspirin had a significantly lower risk of c-TRAS than those who were not treated(log-rank P=0.001,HR=0.23,95%confidence interval[CI]:0.09–0.62).The levels of platelet aggregation rate(P<0.001),cholesterol(P=0.028),and low-density lipoprotein cholesterol(P=0.003)in the aspirin group were decreased compared with the control group in the third-month post-transplantation.For the incidence of adverse events,there was no statistical difference.Conclusion:Clinical application of low-dose aspirin after renal transplant could prevent the development of TRAS with no significant increase in adverse effects.Trial Registration:Clinicaltrials.gov,NCT04260828.