The cost of obesity in radical cystectomy

The prevalence of obesity is on the rise in the Unites States, and obesity has been associated with increased complications and costs in a variety of complex surgeries. However, the contribution of obesity to the overall costs of radical cystectomy has not been studied in detail using contemporary data. Our objective is to assess the variation in healthcare costs due to obesity on the index hospitalization for radical cystectomy in the United States between 2003 and 2015.

This was a retrospective cohort study, using the Premier Healthcare Database, of 1,242 patients who underwent radical cystectomy and were either overweight (25  ≤  body mass index [BMI] < 30), obese (30  ≤  BMI < 40), or morbidly obese (BMI ≥ 40). The primary outcome costs of the index hospitalization for each BMI category. Multivariable median regression was used to identify drivers of increased costs.

The cost of the index hospitalization for cystectomy was $24,596 (95% confidence interval [CI], $22,599-$26,592) for overweight patients. The costs for obese and morbidly obese patients were $2,158 (95% CI, -$80 to $4,395, P = 0.059) and $5,308 (95% CI, $2,652-$7,964, P < 0.001) higher compared to overweight patients, respectively. After adjustment for operative time or length of stay in the multivariable models, there were no longer any differences in cost. Operative time was prolonged as BMI increased (median operative time for overweight, obese, and morbidly obese: 346, 391, and 420 minutes, respectively P = 0.0001). Median length of stay was 1 day shorter for overweight vs. morbidly obese patients (P = 0.0030), with each additional day costing $1,738 (95% CI, $1,654 to $1,821, P < 0.0001) on multivariable analysis.

The cost of radical cystectomy is greater for obese and morbidly obese patients compared to overweight patients. The increased financial cost is driven by increased operative times and longer length of stay.