Health Expenditures After Bariatric Surgery: A Retrospective Cohort Study.

Abstract

Bariatric surgery leads to substantial improvements in weight and weight-related conditions, but prior literature on post-surgical health expenditures is equivocal. In a retrospective cohort study, we compared expenditures between surgical and matched non-surgical patients. In a retrospective study, total, outpatient, inpatient and medication expenditures 3 years before and 5.5 years after surgery were compared between 22,698 bariatric surgery (n=7,127 RYGB, 15,571 sleeve gastrectomy) patients from 2012-2019 and 66,769 matched non-surgical patients, using generalized estimating equations. We also compared expenditures between patients receiving the two leading surgical procedures in weighted analyses. Surgical and non-surgical cohorts were well matched, 80-81% female, with mean body mass index (BMI) of 44, and mean age of 47 (RYGB) and 44 (SG) years. Estimated total expenditures were similar between surgical and non-surgical groups 3 years before surgery ($27 difference, 95% confidence interval (CI): -42, 102)), increased 6 months prior to surgery for surgical patients, and decreased below pre-period levels for both groups after 3-5.5 years to become similar (difference at 5.5y=-$61, 95% CI: -166, 52). Long-term outpatient expenditures were similar between groups. Surgical patients' lower long-term medication expenditures ($314 lower at 5.5y, 95% CI: -419, -208) were offset by a higher risk of hospitalization. Total expenditures were similar between RYGB and SG patients 3.5 to 5.5 years after surgery. Bariatric surgery translated into lower medication expenditures than matched controls, but not lower overall long-term expenditures. Expenditure trends appear similar for the two leading bariatric operations.