Pre-surgical factors related to latent trajectories of 5-year weight loss for a diverse bariatric surgery population

Background Analyzing trajectories of weight loss may address how particular groups of patients respond to metabolic and bariatric surgery. Objectives The Bariatric Experience Long Term (BELONG) study was designed to use a theoretical model to examine determinants of weight loss and recurrence. Setting Large integrated health system in Southern California with 11 surgical practices and 23 surgeons. Methods A total of n = 1338 patients who had metabolic and bariatric surgery were surveyed before surgery to measure factors related to median percent total weight loss (%TWL) over 5 years. Longitudinal weight data were available for n = 1024 (76.5% of the sample). Data were analyzed using latent growth mixture models (GMM) to estimate trajectories of weight change separately for gastric sleeve and bypass operations. These trajectories were then described using relevant variables from the baseline survey. Results For both gastric sleeve (n = 733) and bypass (n = 291) operations, 3 latent trajectories of median %TWL were found corresponding to most, moderate, and least %TWL. Sleeve trajectories were distinguished by body mass index at surgery and geocoded environmental factors. Bypass trajectories varied by self-reported and geocoded environmental factors, comorbidity burden, race, experiential avoidance, and weight control strategies. Conclusions Future research should examine the role of the built and perceived environment in surgical weight loss. Bariatric practices should focus less on the presurgical period for predictors of long-term weight loss and begin efforts to monitor real-time patient-reported outcomes to help tailor intervention strategies for patients who either do not lose an expected amount of weight or who begin to experience weight recurrence.