The bariatric operations most commonly performed in the United States are vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB). However, helping patients determine which of these two operations may be the most appropriate treatment option can be challenging. Factors that influence this choice are body mass index (BMI), surgical risk, metabolic complications, and patient preference. Previous research has shown that psychological problems are common presurgery and may contribute to less than optimal weight loss. The purpose of this study was to investigate associations between psychological correlates and weight loss for patients who underwent RYGB or VSG.
The cohort of 422 patients (RYGB = 305; VSG = 117) included in the study underwent bariatric surgery between August 2012 and April 2015 at a multisite medical center. They completed presurgery screening questionnaires measuring depression, anxiety, sexual abuse, alcohol use, binge eating, night eating, food addiction, and weight management self-efficacy. Demographics and weight outcomes were extracted from our MBSAQIP database. Associations between demographics and screening questionnaires with percentage weight change from baseline to one and two year follow-up were evaluated using multivariable linear regression models separately for RYGB and VSG.
Presurgery demographics included: median age 48 years; female gender (76%); Caucasian (94%); and median BMI 45.3 kg/m2. The median percentage changes in weight from baseline to one and two year follow-up were -31.5% (Range: -52.2% to -9.2%) and -31.2% (Range: -50.0% to -1.2%) for RYGB, respectively. For VSG, the median percentage changes in weight from baseline to one and two year follow-up were -25.3% (Range: -49.8% to -4.7%) and -23.3% (Range: -58.9% to -1.6%), respectively. Linear regression models revealed that the only significant association with percentage weight change was age where younger patients lost significantly more weight than older patients at one year follow-up (RYGB <.0001; VSG P=.0001) and two year follow-up (RYGB P=0.005; VSG P=.002). Post hoc analyses comparing 1245 patients in the same cohort who did not undergo surgery to surgical patients revealed significantly higher rates of depression (P< .001), anxiety (P< .001), binge eating (P=.003), night eating (P<.001), food addiction (P=.042), and lower self-efficacy (P<.001) among nonsurgical patients.
Results suggest patients who are psychologically higher functioning may experience optimal weight loss outcome with either RYGB or VSG in the first two years after surgery. Yet, how poorly managed psychological problems presurgery may influence weight loss outcome postsurgery is unclear.