BACKGROUND AND OBJECTIVES: Endovascular repair (EVAR) is a common treatment for abdominal aortic aneurysm (AAA). However, its long-term effects on renal function remain unclear. We aimed to assess long-term renal dysfunction after EVAR using a contemporary estimate of GFR and to compare long-term renal outcomes in patients after EVAR with open aneurysm repair (OAR) and in patients without an AAA.DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS: We performed a nested case-matched analysis of 726 patients (using a prospectively maintained database for repairs that took place between January 2000 and May 2010 in a tertiary center): 121 patients undergoing OAR (with data at baseline and 5 years postrepair) were case matched (age, sex, smoking, diabetes, baseline eGFR) to patients undergoing suprarenal and infrarenal fixation EVAR (242 in each group) and to 121 patients undergoing carotid endarterectomy (CEA) without AAA. Changes in eGFR were compared (1 and 5 years).RESULTS: The OAR patients lost an average of 7.4 ml/min per 1.73 m2 at 5 years (95% confidence interval [95% CI], 4.8 to 10.6), compared with 8.2 ml/min per 1.73 m2 (95% CI, 6.5 to 10.8; P<0.001) for infrarenal-fixation EVAR, 16.9 ml/min per 1.73 m2 (95% CI, 13.0 to 21.9, P<0.001) for suprarenal-fixation EVAR, and 5.4 ml/min per 1.73 m2 (95% CI, 1.7 to 7.5; P<0.001) for CEA. The decrease in eGFR was steeper during the first postoperative year, with each group losing -2.2 ml/min per 1.73 m2 (infrarenal-fixation EVAR), -10.7 ml/min per 1.73 m2 (suprarenal-fixation EVAR), and -4.6 ml/min per 1.73 m2 (OAR), compared with -1.9 ml/min per 1.73 m2 for CEA.CONCLUSIONS: Elective EVAR is associated with a significant decline in eGFR after 5 years, which is steeper in the first postoperative year and more pronounced compared with a similar population with atherosclerotic disease.