Clinical Research Directory

Disordered Eating and Recurrent Weight Gain After MBS

Obesity represents an increasingly serious public health problem worldwide. According to the World Health Organization, one in eight individuals globally is affected by obesity. Bariatric surgery (BS) is recognized as the most effective treatment for severe obesity and has been shown to significantly improve obesity-related comorbidities. However, despite initially successful surgical outcomes, a substantial proportion of patients experience insufficient weight loss (IWL) or weight regain (WR) after surgery. Previous studies have identified multiple factors associated with post-bariatric IWL and WR, including older age, low socioeconomic status, higher baseline body mass index (particularly preoperative BMI \>50 kg/m²), type of surgical procedure, hormonal mechanisms, poor adherence to postoperative dietary recommendations, maladaptive eating behaviors, insufficient physical activity, and the presence of psychiatric comorbidities. Among these, behavioral factors appear to play a particularly critical role. Irregular eating patterns such as loss of control eating, maladaptive behaviors such as grazing, non-adherence to dietary guidelines, and a return to preoperative eating habits are frequently associated with weight regain. Additionally, physiological mechanisms, including increased appetite, food cravings, and altered hormonal regulation of energy intake, may further contribute to this process. Grazing behavior-defined as repetitive consumption of small amounts of food accompanied by a sense of loss of control-has been consistently associated with poorer weight outcomes after bariatric surgery. A large meta-analysis reported grazing prevalence rates between 16.6% and 46.6%, with weight regain observed in nearly half of post-bariatric patients. Moreover, lack of structured nutritional follow-up has been shown to significantly increase the risk of weight regain. Neurobehavioral changes also occur after surgery: while appetite and responsiveness to palatable foods typically decrease during the first postoperative year, these effects often diminish over time, with hunger, cravings, and portion sizes gradually increasing in some individuals. Long-term weight regain has been closely linked to disordered eating behaviors, including emotional eating, binge eating, compulsive eating, food addiction, and loss of control eating. Recent studies have demonstrated significant associations between weight regain and binge eating disorder, eating disinhibition, and impulsivity. Qualitative research further highlights that many patients struggle to manage emotional eating and require ongoing psychological and dietary support following surgery. Despite growing evidence emphasizing the behavioral and psychological components of post-bariatric outcomes, comprehensive studies that simultaneously evaluate nutritional status, eating disorders, and emotional factors in individuals experiencing IWL or WR remain limited. Therefore, the present study aims to assess nutritional status, eating disorder symptoms, and emotional factors in individuals who experience insufficient weight loss or weight regain after bariatric surgery. By integrating anthropometric, nutritional, behavioral, and emotional assessments within the same sample, this study seeks to provide a multidimensional perspective and contribute to the development of more effective multidisciplinary follow-up and psychodietetic interventions.

Naltrexone/Bupropion With or Without Very Low Calorie Ketogenic Diet for Weight Regain After Bariatric Surgery

The goal of this clinical trial is to evaluate the superiority of combined VLCKD, intensive lifestyle intervention and naltrexone/bupropion (N/B) versus standard of care with naltrexone/bupropion on weight loss for people with weight regain after bariatric surgery. The main questions it aims to answer are: Primary endpoint: • The percentage of weight loss at 26 weeks Secondary endpoints: * A weight loss percentage at 10 weeks, 16 weeks and at end of trial (= 52 weeks from start) * A proportion of patients with a weight loss percentage of 5% or more at 10, 16, 26 and 52 weeks * A proportion of patients with a weight loss percentage of 10% or more at 10, 16, 26 and 52 weeks * The time to reach a weight loss percentage of 5% and 10% * The dose of naltrexone/bupropion used at 10, 16, 26 and 52 weeks and at the end of the trial * The tolerability of VLCKD and NB * The adherence to VLCKD and NB * The Patient-Reported Outcome Measures (PROMs) of hunger and cravings at 0, 4, 10, 16, 26 and 52 weeks * The change in fasting glucose, lipids and blood pressure at 10, 16, 26 and 52 weeks Researchers will compare an experimental arm (N/B + Lifestyle + VLCKD) with comparator arm (NB + lifestyle) to see if combined VLCKD, intensive lifestyle and N/B is superior. Participants will: * get NB and lifestyle changes for 26 weeks * follow a VLCKD in the first 10 weeks on top of it, if they belong to the experimental arm * follow NB combined with lifestyle the remaining 16 weeks * be followed-up for an extension of 26 weeks * come to the hospital at week 1, 10, 16, 26, 52