Comparison of safety and healthcare utilization following sleeve gastrectomy or gastric bypass among medicare beneficiaries using sex as a biologic variable

Abstract

Background: Bariatric surgery is a common operation, but differences in outcomes between males and females are unknown.

Objectives: To compare the risk of mortality, complications, reintervention, and healthcare utilization after sleeve gastrectomy or gastric bypass using sex as a biologic variable.

Setting: United States.

Methods: Retrospective cohort study of adults undergoing sleeve gastrectomy or gastric bypass from January 1, 2012 to December 31, 2018 using Medicare claims data. We performed a heterogeneity of treatment effect analysis to determine the impact of sleeve gastrectomy versus gastric bypass comparing males to females. The primary outcome was safety (mortality, complications, and reinterventions) up to 5 years after surgery. The secondary outcome was healthcare utilization (hospitalization and emergency department use).

Results: Among 95,405 patients the majority (n = 71,348; 74.8%) were female and most (n = 57,008; 59.8%) underwent sleeve gastrectomy. For all patients, compared to gastric bypass, sleeve gastrectomy was associated with a lower risk of complications and reintervention but a higher risk of revision. Compared to gastric bypass, sleeve gastrectomy was associated with a lower risk of mortality for females (adjusted hazard ratio .86, 95% CI .75-.96) but not males. We found no difference in procedure treatment effect by sex for mortality, hospitalization, emergency department use, or overall reintervention when comparing sleeve to gastric bypass.

Conclusions: Females and males have similar outcomes following bariatric surgery. Females have a lower risk of complications but a higher risk of reintervention. Decisions surrounding treatment for this common procedure should be tailored to include a discussion of sex-specific differences in treatment outcome.

Keywords: Bariatric surgery; Sex as a biologic variable.