B. T. Fox1, E. Y. Chen1, A. Suzo2, S. A. Jolles1, J. A. Greenberg1, G. M. Campos1, M. J. Garren1, C. I. Voils3,4, L. M. Funk1 3Center For Health Services Research In Primary Care,Department Of Veterans Affairs,Durham, NC, USA 4Duke University Medical Center,Department Of Medicine,Durham, NC, USA 1University Of Wisconsin,Department Of Surgery,Madison, WI, USA 2Ohio State University,Department Of Surgery,Columbus, OH, USA
Introduction
Identifying morbidly obese patients who will succeed following bariatric surgery remains challenging. While numerous studies have focused on preoperative factors associated with weight loss following bariatric surgery, the critical nutritional and psychological characteristics remain unclear. The purpose of this study was to measure the association between preoperative nutritional and psychological characteristics and the likelihood of successful weight loss among bariatric patients.
Methods
Our study is a retrospective cohort study of all patients who underwent primary laparoscopic Roux-en-Y gastric bypass from September 1, 2011 to June 1, 2013 at the University of Wisconsin Hospital and Clinics (124 patients). Patient demographics, comorbidities, nutritional and psychological factors, and excess weight loss were collected from the electronic medical record. “Successful” weight loss was defined as loss of ≥ 50% of excess body weight one year after surgery. To evaluate bivariate associations between predictors and successful weight loss, Fisher’s exact and student’s T-tests were used for categorical and continuous variables, respectively. Variables significant (p<.05) in bivariate analyses were included in a multivariable logistic regression model with successful weight loss as the outcome.
Results
78% (n=97) of patients had at least one year of follow-up data and were included in analyses. Of those, 69% (67) experienced successful weight loss. Mean excess body weight loss was 69.0% (+/- 16.6%) for these patients vs. 39.0% (+/- 9.4%) for patients with suboptimal weight loss (p=0.01). In bivariate analyses, successful weight loss was associated with lower preoperative weight (268.1 vs. 301.4 lbs, p=0.02), a lower maximum past weight loss attempt (40.0 vs. 65.6 lbs, p=0.01), no diabetes history (81.4% of non-diabetics vs. 59.3% of diabetics were successful, p=0.03), being able to quit soda consumption before surgery (81.8% who quit vs. 59.3% with unchanged drinking habits were successful, p=0.04) and greater autonomy (mean percentile rank of 68.7% in successful vs. 38.8% in unsuccessful patients, p=0.01). On multivariate analysis, diabetes and a past weight loss > 50 lbs were inversely associated with success (Table 1).
Conclusion
Dietary habits and psychological characteristics were not associated with weight loss success after adjusting for measurable confounders. Identification of predictive dietary and psychological variables for patients in our program remains elusive. Diabetic patients warrant especially close follow-up after surgery given their propensity to experience suboptimal weight loss.
