The Cost of Obesity for Nonbariatric Inpatient Operative Procedures in the United States: National Cost Estimates Obese versus Nonobese Patients

Objective: To evaluate the economic impact of obesity on hospital costs associated with the commonest nonbariatric, nonobstetrical surgical procedures. Background: Health care costs and obesity are both rising. Nonsurgical costs associated with obesity are well documented but surgical costs are not. Methods: National cost estimates were calculated from the Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database, 2005–2009, for the highest volume nonbariatric nonobstetric procedures. Obesity was identified from the HCUP-NIS severity data file comorbidity index. Costs for obese patients were compared with those for nonobese patients. To control for medical complexity, each obese patient was matched one-to-one with a nonobese patient using age, sex, race, and 28 comorbid defined elements. Results: Of 2,309,699 procedures, 439,8129 (19%) were successfully matched into 2 medically equal groups (obese vs nonobese). Adjusted total hospital costs incurred by obese patients were 3.7% higher with a significantly (P < 0.0001) higher per capita cost of $648 (95% confidence interval [CI]: $556–$736) compared with nonobese patients. Of the 2 major components of hospital costs, length of stay was significantly increased in obese patients (mean difference = 0.0253 days, 95% CI: 0.0225–0.0282) and resource utilization determined by costs per day were greater in obese patients due to an increased number of diagnostic and therapeutic procedures needed postoperatively (odds ratio [OR] = 0.94, 95% CI: 0.93–0.96). Postoperative complications were equivalent in both groups (OR = 0.97, 95% CI: 0.93–1.02). Conclusions: Annual national hospital expenditures for the largest volume surgical procedures is an estimated $160 million higher in obese than in a comparative group of nonobese patients.