Bladder cancer is a common condition in the field of urology. Numerous studies have identified the Controlling Nutritional Status (CONUT) score as a valuable tool for predicting tumor-related outcomes. This study aims to investigate whether patients with bladder cancer who exhibit higher CONUT scores prior to undergoing radical cystectomy are at increased risk of developing severe postoperative complications, defined as Clavien-Dindo Grade ≥ 3. The findings may offer important insights for guiding clinical decision-making.

Clinical questions were formulated using evidence-based principles and the PICO framework. Relevant keywords and MeSH terms were applied, and Boolean logic was used to conduct comprehensive searches in databases including PubMed, the Cochrane Library, and the Airiti Library. An initial search yielded 8 articles. After removing duplicates and studies that did not meet the inclusion criteria or align with the PICO focus, 2 articles were selected for final analysis. The quality of the included non-randomized studies was assessed using the ROBINS-I (Risk Of Bias In Non-randomized Studies - of Interventions).

A total of 462 patients were included across the two selected studies. Meta-analysis was performed using Review Manager software (version 5.4). The results demonstrated that patients with higher CONUT scores had a significantly increased risk of developing high-grade postoperative complications compared to those with lower scores. The calculated risk ratio (RR) was 2.27 (95% confidence interval: 1.58–3.27, p < 0.01, I² = 78%).

Based on the literature review and meta-analysis, patients with higher CONUT nutritional scores are more likely to experience severe postoperative complications following radical cystectomy for bladder cancer. These findings suggest that the CONUT score may serve as a useful predictive tool in preoperative assessments, enabling clinicians to identify high-risk patients and tailor management strategies accordingly to enhance patient outcomes and well-being.