Association of obesity and different metabolic status with prognosis in patients with bladder cancer: a retrospective cohort study

Background and objectives:Patients with bladder cancer (BC) are at high risk for recurrence rates and readmission costs. However, the evidence about obesity and metabolic abnormalities on the BC prognosis was inconsistent. Our primary aim was to determine the impact of obesity and different metabolic status on the readmission risk in patients with BC.Design and methods:We identified 16,649 patients with BC using the 2018 Nationwide Readmissions Database who were hospitalized from January to June 2018 and followed for 180 days. The primary outcome was 180-day readmission. The multivariate Cox regression analysis and ordered logistic regression were performed to analyze data.Results:Obesity and metabolic abnormalities were associated with an increased readmission risk in patients with BC [obesity: adjusted hazard ratio (aHR) = 1.08, 95% confidence interval (CI): 1.01-1.16; hyperglycemia: aHR = 1.11, 95% CI: 1.05-1.17; hypertension: aHR = 1.09, 95% CI: 1.03-1.15]. Compared with non-obese and no metabolic abnormalities, the risk of readmission was significantly increased in patients with metabolic abnormalities, irrespective of obesity (non-obese and metabolic abnormalities: aHR = 1.07, 95% CI: 1.02-1.13; obese and metabolic abnormalities: aHR = 1.20, 95% CI: 1.10-1.31), but not in obese and no metabolic abnormalities. These associations were consistent in patients aged 60 years or older and the surgery group. Moreover, hyperglycemia, hypertension, and a graded increment of metabolic risk were associated with an increased readmission risk. We also found increased length of stay for readmission in patients with obesity and metabolic abnormalities (aOR = 1.17, 95% CI: 1.00-1.36).Conclusion:Obesity with metabolic abnormalities and metabolic abnormalities alone were associated with higher readmission risks in patients with BC. It is suggested that prevention should focus not only on obesity but also on metabolic abnormalities to decrease the risk of readmission.