Proactive Cystoscopic Debris Removal for Reducing Catheter Blockage in Patients with Long-Term Indwelling Catheters: A Prospective Self-Selected Cohort Study with Exploratory Subgroup Analysis on Urinary Tract Infections.

Background: Catheter-associated urinary tract infections (CAUTIs) are a major concern in patients with long-term indwelling urinary catheters, especially those with neurogenic bladder. This study assessed whether proactive cystoscopic removal of bladder debris reduces symptomatic UTI incidence and catheter blockage. Methods: This prospective, self-selected cohort study was conducted between January 2022 and December 2025 at a tertiary center in Taiwan. Enrollment occurred from January 2022 to June 2024, with follow-up completed by December 2025. Patients chose standard CDC-guided care (control, n = 63) or standard care plus flexible cystoscopy every 3 months for gentle low-volume evacuation (<100 mL normal saline) of dependent bladder debris (intervention, n = 141). Inverse probability of treatment weighting (IPTW) was used to address selection bias. Symptomatic UTIs were prospectively recorded using strict criteria. Cumulative incidence was analyzed with Kaplan-Meier methods and multivariable Cox regression. Results: After IPTW, baseline characteristics were well balanced. Median follow-up was 26 months (IQR 18-34). The incidence of catheter blockage was significantly lower in the intervention group (7.8% vs. 22.2%, p = 0.004). In the overall cohort, the reduction in symptomatic UTI incidence did not reach statistical significance (49.2% vs. 36.9%, p = 0.092). In the pre-specified spinal cord injury (SCI) subgroup (n = 71), the intervention was associated with improved UTI-free survival (log-rank p = 0.03; adjusted HR 0.52, 95% CI 0.28-0.96, p = 0.037; treatment × SCI interaction p = 0.042). All adverse events were Clavien-Dindo Grade I. No major complications occurred. Conclusions: Proactive gentle cystoscopic debris removal was associated with reduced catheter blockage. A signal toward lower symptomatic UTI risk was observed in the SCI subgroup, but not in the overall cohort. Due to the self-selected design and residual confounding, these findings are hypothesis-generating.