To evaluate long‐term renal function in patients with chronic kidney disease (CKD) Stage IIIa who underwent radical cystectomy and orthotopic neobladder (RC/ONB) compared to matched controls.

Using our Institutional Review Board‐approved institutional database, patients with a glomerular filtration rate (GFR) of 45–59.9 mL/min/1.73 m² who underwent RC/ONB were identified. A control group of patients with a GFR of ≥60 mL/min/1.73 m² was selected. Groups were matched based on age, baseline hypertension/diabetes mellitus, perioperative chemotherapy, and preoperative hydronephrosis. A decrease in GFR of >10 mL/min/1.73 m² during the follow‐up was considered significant. A multivariate Cox regression analysis was performed to identify predictors of GFR decline in each group.

Of 1237 patients who underwent RC/ONB, 508 patients were included (254 per group). The mean preoperative GFR was 53.3 mL/min/1.73 m² in the study group and 78.8 mL/min/1.73 m² in controls. The median follow‐up was 3.7 years. During follow‐up, GFR stayed at or above baseline in 51% of the study patients compared to 46% of the controls (P = 0.5). The mean time to a significant GFR decline in the study patients was significantly longer compared to the controls (5.6 vs 2 years, respectively; P < 0.001). In multivariate analysis, neoadjuvant chemotherapy was found to be the strongest predictor of a significant GFR decline as well as GFR decline below baseline (hazard ratio [HR] 2.15, 95% confidence interval [CI] 1.4–3.29, P = 0.004; and HR 2.15, 95% CI 1.4–3.29, P < 0.001, respectively).

Patients with CKD Stage IIIa who undergo ONB appear to have comparable long‐term renal function to those with a GFR of ≥60 mL/min/1.73 m². An ONB reconstruction is a safe option for patients with CKD Stage IIIa desiring a continent diversion.