Ileal conduit versus neobladder: A propensity score-matched analysis of the effect on renal function

To analyze the long-term effects of continent (neobladder) compared with incontinent (ileal conduit) urinary diversion.

We carried out a retrospective review of our departmental database. Estimated glomerular filtration rate was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. Neobladder and ileal conduit patients were matched in a 1:2 ratio and a propensity score-matched analysis was carried out. Data were summarized using descriptive analysis. Trend plots were generated using baseline and follow-up creatinine values to compare estimated glomerular filtration rate at 3 months, then annually for 5 years. Variables associated with estimated glomerular filtration rate were assessed using multivariate linear analysis.

Our cohort consisted of 137 patients (neobladder n = 50 and ileal conduit n = 87) with a median follow-up time of 3 years (interquartile range 1-7 years). The ileal conduit group had shorter operative times (352 vs 444 min, P < 0.01), intracorporeal diversions were more common (66% vs 44%, P = 0.01), had prior abdominal surgery (66% vs 38%, P < 0.01) and had radiation (9% vs 0%, P = 0.03). The neobladder group more commonly had recurrent urinary tract infections (22% vs 3%, P < 0.01) and a steeper decrease in estimated glomerular filtration rate in the first year. On multivariate linear analysis, age/year (-0.59), body mass index per kg/m² (-0.52), preoperative estimated glomerular filtration rate per unit (0.51), recurrent urinary tract infections (-14.03) and time versus day 90 (year 1, -7.52; year 2, -9.06; year 3, -10.78) were significantly associated with estimated glomerular filtration rate.

Ileal conduits and neobladders showed a similar effect on the estimated glomerular filtration rate up to 5 years after robot-assisted radical cystectomy. Recurrent urinary tract infections were associated with a worse estimated glomerular filtration rate.