Bariatric surgery decreases the number of first-time hospital admissions for cancer in severely obese patients. A retrospective analysis of the National Inpatient Sample database.

BACKGROUND

According to the U.S. Centers for Disease Control, cancers linked to overweight or obesity accounted for roughly 40% of all U.S. malignancies in 2014.

OBJECTIVES

The primary aim of this epidemiologic study was to assess whether bariatric surgery might have any preventative role against obesity-linked cancers among individuals with obesity.

SETTING

Hospitals across the United States participating in the National Inpatient Sample database, created, updated, and monitored by the U.S. Healthcare Cost and Utilization Project.

METHODS

National Inpatient Sample data collected from 2010 to 2014 were examined to identify any difference in the number of first cancer-related hospitalizations, as a proxy for cancer incidence, between patients with a history of prior bariatric surgery (cases) and those without (controls). Patients with any prior cancer diagnosis were excluded. To match the body mass index ≥35 kg/m generally required for bariatric surgery, all controls had to have a body mass index ≥35 kg/m. International Classification of Diseases-9 codes were employed to identify admissions for 13 obesity-linked cancers. Multivariate logistic regression analysis was performed to identify any case-control differences, after matching for all baseline demographic, co-morbidity, and cancer risk-factor variables. All percentages and means (with confidence intervals) were weighted, per Healthcare Cost and Utilization Project guidelines.

RESULTS

Among 1,590,579 controls and 247,015 bariatric surgery cases, there were 29,822 (1.93%; 95% confidence interval 1.91-1.96) and 3540 (1.43%; 1.38-1.47) first hospitalizations for cancer (adjusted odds ratio 1.17; 1.13-1.23; P < .0001).

CONCLUSIONS

Preliminary findings from a large U.S. database suggest that bariatric surgery may reduce the incidence of cancer in patients considered at high risk because of severe obesity.