Risk factors of transplant renal artery stenosis in kidney transplant recipients

Background: Transplant Renal Artery Stenosis (TRAS) is a recognized vascular complication after kidney trans-plantation. The overall risk predictors of TRAS are poorly understood. Methods: Retrospective analysis of patients with suspected TRAS (Doppler ultrasound PSV > 200 cm/s) who underwent angiographic study in a single center between 2007 and 2014. All patients with stenosis > 50% were considered with TRAS. Stenosis restricted in the body of the artery was also analyzed in a subgroup. Results: 274 patients were submitted to a renal angiography and 166 confirmed TRAS. TRAS group featured an older population (46.3 +/- 11.0 vs. 40.9 +/- 14.2 years; p = 0.001), more frequent hypertensive nephropathy (30.1% vs. 15.7%; p = 0.01), higher incidence of Delayed Graft Function (DGF) (52.0% vs. 25.6%; p < 0.001) and longer Cold Ischemia Time (CIT) (21.5 +/- 10.6 vs. 15.7 +/- 12.9h; p < 0.001). In multivariable analyses, DGF (OR = 3.31; 95% CI 1.78-6.30; p < 0.0001) was independent risk factors for TRAS. DM and CIT showed a ten-dency towards TRAS. The compound discriminatory capacity of the multivariable model (AUC = 0.775; 95% CI 0.718-0.831) is significantly higher than systolic blood pressure and creatinine alone (AUC = 0.62; 95% CI 0.558 & minus;0.661). In body artery stenosis subgroup, DGF (OR = 1.86; 95% CI 1.04-3.36; p = 0.03) and Dia-betes Mellitus (DM) (OR = 2.44; 95% CI 1.31-4.60; p = 0.005) were independent risk factors for TRAS. Conclusion: In our transplant population, DGF increased more than 3-fold the risk of TRAS. In the subgroup analy-sis, both DGF and DM increases the risk of body artery stenosis. The addition of other factors to hypertension and renal dysfunction may increase diagnostic accuracy. TRAS Trial registred: clinicaltrials.gov (n degrees NCT04225338).

Automated summary

In the population of kidney transplant recipients, Delayed Graft Function (DGF) increases the risk of Transplant Renal Artery Stenosis (TRAS) by more than 3-fold. In the subgroup analysis, DGF and Diabetes Mellitus (DM) are independent risk factors for stenosis in the body artery. Adding other factors to hypertension and renal dysfunction may improve diagnostic accuracy.