This study aimed to assess the association between body mass index and perioperative outcomes and survival after radical cystectomy for bladder cancer in an Australian cohort.
We conducted a retrospective single-centre study of patients undergoing radical cystectomy between 2008 and 2021. Preoperative body mass index (BMI) was analysed categorically and continuously. Outcomes included overall survival (OS), Clavien-Dindo grade ≥2 complications and length of hospital stay. Survival was analysed using Kaplan-Meier methods and multivariable Cox regression adjusting for age, sex, tumour stage, nodal status and chemotherapy. Restricted cubic splines were used to explore non-linear associations.
The cohort comprised 135 patients (median age 70 years; median BMI 27.2 kg/m2). Overweight patients had superior OS compared with normal-weight and obese patients (adjusted hazard ratio [HR] 0.42, 95% CI 0.24-0.76). Obesity was associated with higher complication rates and longer hospital stay (p < 0.05). BMI analysed as a continuous variable was not independently associated with OS. Spline modelling demonstrated no significant non-linear association, although the lowest estimated risk occurred in the overweight range.
Overweight BMI was associated with improved survival following radical cystectomy, while obesity was linked to greater perioperative morbidity. These findings are consistent with the obesity paradox and underscore the limitations of BMI alone for perioperative risk stratification.
BJUI compass. 2026 Jul 08*** epublish ***
Samiha Arulshankar, Xinyi Wei, Charis Ting, Tran Ngoc An Huynh, Yashvrdhan Khanna, Kylie Lim, Munad Khan, James Huang, Nieroshan Rajarubendra, Kevin Chu, Matthew Harper, Scott Donnellan, Weranja Ranasinghe
Department of Urology Monash Health Victoria Australia., Faculty of Medicine, Nursing and Health Science Monash University Melbourne Australia.