Low socioeconomic status is associated with lower weight-loss outcomes 10-years after Roux-en-Y gastric bypass.

Background: Roux-en-Y gastric bypass (RYGB) is the criterion standard operation for weight loss. Low socioeconomic status (SES) is common in the Veteran population undergoing bariatric surgery, but the impact of SES on long-term weight-loss outcomes is not known. We hypothesize that low socioeconomic status is associated with less weight loss after gastric bypass in long-term follow-up.

Methods: We performed a retrospective review of patients undergoing RYGB at a single Veterans Affairs (VA) hospital. Patients with at least 10 years of follow-up data in the electronic health record were included in the analysis. Weight loss was measured as percent excess body mass index loss (%EBMIL). The primary predictor variable, median household income, was determined using zip codes of patient residences matched to publicly available 2010 U.S. census data. Univariate relationships between income, weight loss, and other patient characteristics were evaluated. We calculated a multivariate generalized linear model of %EBMIL to estimate independent relationships with median household income quartile while controlling for patients' age, race, sex, and VA distance.

Results: Complete 10-year follow-up data were available for 83 of 92 patients (90.2%) who underwent RYGB between 2001 and 2007 and survived at least 10 years. The majority of patients were male (79.5%) and white (73.5%). The mean 10-year %EBMIL was 57.8% (SD: 29.5%, range - 36.0% - 132.8%). In univariate analysis, income was significantly associated with race (p < 0.001) and median distance to the VA bariatric center (p = 0.034), but income did not differ by gender (p = 0.73) or age (p = 0.45). Multivariate analysis revealed significantly lower 10-year %EBMIL for patients with the lowest income compared to patients with low-mid income (p = 0.03) and mid-high income (p = 0.01), after controlling for gender, race, age, and VA distance.

Conclusions: Low socioeconomic status is associated with lower weight-loss outcomes, 10 years after RYGB. Durable weight loss is observed in all income groups.