Baseline Psychosocial, Environmental, Health, and Behavioral Correlates of 1- and 3-Year Weight Loss After Bariatric Surgery.

Purpose: Weight loss surgery is an effective, long-term treatment for severe obesity but individual response to surgery varies widely. The purpose of this study was to test a comprehensive theoretical model of factors that may be correlated with the greatest surgical weight loss at 1-3 years following surgery. Such a model would help determine what predictive factors to measure when patients are preparing for surgery that may ensure the best weight outcomes.

Materials And Methods: The Bariatric Experience Long Term (BELONG) study collected self-reported and medical record-based baseline information as correlates of 1- and 3-year % total weight loss (TWL) in n = 1341 patients. Multiple linear regression was used to determine the associations between 120 baseline variables and %TWL.

Results: Participants were 43.4 ± 11.3 years old, Hispanic or Black (52%; n = 699), women (86%; n = 1149), and partnered (72%; n = 965) and had annual incomes of ≥ $51,000 (60%; n = 803). A total of 1006 (75%) had 3-year follow-up weight. Regression models accounted for 10.1% of the variance in %TWL at 1-year and 13.6% at 3 years. Only bariatric operation accounted for a clinically meaningful difference (~ 5%) in %TWL at 1-year. At 3 years after surgery, only bariatric operation, Black race, and BMI ≥ 50 kg/m were associated with clinically meaningful differences in %TWL.

Conclusions: Our findings combined with many others support a move away from extensive screening and selection of patients at the time of surgery to a focus on improving access to this treatment.