ObjectiveChronic kidney disease (CKD) is a recognized predictor of long-term survival, frequently coexisting with peripheral arterial disease (PAD). Estimated glomerular filtration rate (eGFR) is a more accurate marker of renal function than creatinine. This study sought to determine the graded impact of CKD, defined by eGFR, on infrainguinal lower extremity bypass (LEB) outcomes. MethodsThis retrospective study examined 44,332 patients from the Vascular Quality Initiative database who underwent LEB between January 2003 and November 2019. The GFR was estimated using the Modification of Diet in Renal Disease equation. Multivariable logistic regression was used to study perioperative mortality and Kaplan-Meier survival estimation and multivariable Cox regression were used to evaluate 5-year mortality, 1-year major amputation, and major amputation/death. ResultsThe 30-day mortality odds was increased for CKD 3 (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.32-1.91; P < .001) and CKD 5 (OR, 3.08; 95% CI, 2.45-3.87; P < .001) relative to CKD 1 to 2. Comparing CKD stages 3, 4, and 5 with CKD 1 and 2, there was a stepwise increase in the adjusted hazard of 5-year mortality (hazard ratio [HR], 1.18; 95% CI, 1.09-1.27; P < .001), (HR, 1.73; 95% CI; 1.47-2.03; P < .001) and (HR, 2.58; 95% CI, 2.33-3.84; P < .001), respectively. Although the risk of 1-year death or major amputation did not differ for CKD 3 compared with CKD 1, this was 50% higher for CKD 4 (HR, 1.50; 95% CI, 1.26-1.78; P < .001) and doubled for CKD 5 (HR, 2.07; 95% CI, 1.87-2.29; P < .001) compared with CKD 1 and 2. The adjusted HR for major amputation in 1 year was 0.81 (95% CI, 0.71-0.92; P = .002), 1.14 (95% CI, 0.84-1.54; P = .396) and 1.56 (95% CI,1.31-1.84; P < .001) for CKD 3, 4, and 5, respectively, compared with CKD 1 and 2. ConclusionsThe estimated GFR is a useful predictor of postoperative mortality, overall survival, and/or amputation after LEB in patients with PAD. It should be considered in the preoperative risk-benefit analysis process to guide patient selection in the population with concomitant PAD and CKD being considered for LEB.