A randomized controlled trial investigating the effect of liraglutide on self-reported liking and neural responses to food stimuli in participants with obesity.

BACKGROUND/OBJECTIVES: Obesity is a complex condition and the mechanisms involved in weight gain and loss are not fully understood. Liraglutide, a GLP-1 receptor agonist, has been demonstrated to successfully promote weight loss in patients with obesity (OB). Yet, it is unclear whether the observed weight loss is driven by an alteration of food liking. Here we investigated the effects of liraglutide on food liking and the cerebral correlates of liking in OB. SUBJECTS/METHODS: This study was a randomized, single-center, double-blind, placebo-controlled, parallel group, prospective clinical trial. 73 participants with OB and without diabetes following a multidisciplinary weight loss program, were randomly assigned (1:1) to receive liraglutide 3.0 mg (37.40 ± 11.18 years old, BMI = 35.89 ± 3.01 kg) or a placebo (40.04 ± 14.10 years old, BMI = 34.88 ± 2.87 kg) subcutaneously once daily for 16 weeks. INTERVENTIONS/METHODS: We investigated liking during food consumption. Participants reported their hedonic experience while consuming a high-calorie food (milkshake) and a tasteless solution. The solutions were administered inside the scanner with a Magnetic Resonance Imaging (MRI)-compatible gustometer to assess neural responses during consumption. The same procedure was repeated during the pre- and post-intervention sessions. RESULTS: None of the effects involving the intervention factor reached significance when comparing liking between the pre- and post-intervention sessions or groups. Liking during food reward consumption was associated with the activation of the ventromedial prefrontal cortex (vmPFC) and the amygdala. The liraglutide group lost more weight (BMI post-pre = -3.19 ± 1.28 kg/m2) than the placebo group (BMI post-pre = -0.60 ± 1.26 kg/m2). CONCLUSIONS: These results suggest that liraglutide leads to weight loss without self-report or neural evidence supporting a concomitant reduction of food liking in participants with OB.

[Eating disorder and food addiction in a population candidates for a bariatric surgery]. / Troubles du comportement alimentaire, addiction à la nourriture et chirurgie bariatrique.

Non stabilized severe eating disorder is a contra-indication for bariatric surgery. Specific cares can stabilize this disorder, and therefore a surgery can be undertaken. In this respect, more and more attention is paid to the concept of food addiction even if its definition is still debated. Some authors, according to neurobiological data, consider food addiction as independent from eating disorder, but others see food addiction as a severe sub-type of eating disorder. To contribute to this debate, we performed a study in our department including 23 subjects candidates for a bariatric surgery and found a significant association between food addiction and eating disorder, independently of the body mass index. Clarification of the food addiction concept should permit to reconsider the specific cares needed by these obese patients.

Les troubles du comportement alimentaire (TCA) sévères non stabilisés sont une contre-indication à la chirurgie bariatrique. Une prise en charge spécifique peut permettre de stabiliser ces troubles et d'autoriser ainsi une chirurgie. Le concept d'addiction à la nourriture émerge de plus en plus même s'il reste encore débattu. Certains auteurs, en s'appuyant sur des bases neurobiologiques, le considèrent comme un trouble indépendant des TCA et d'autres l'envisagent plutôt comme un sous-type sévère. Une étude réalisée dans notre service chez 23 sujets candidats à la chirurgie bariatrique a montré une association significative entre les TCA et l'addiction à la nourriture, et ce indépendamment de l'indice de masse corporelle. Préciser le concept d'addiction à la nourriture permettrait de pouvoir repenser la prise en charge de ces patients.

[How to support obese patients in a long-term process of change?]. / Comment accompagner les patients obèses dans un processus de changement à long-terme?

It is illusory to think losing weight effectively by acting only on diet or physical activity. To lose weight satisfactorily and to maintain that weight loss, we should move more on lifestyle changes, namely changes in behavior on several axes. Through concrete examples of an obese patient wanting to lose weight, we will see what skills he must acquire to achieve its objective and what tools the therapist can use to help.

[Not all patients might benefit from gastric by-pass]. / Pas tous égaux devant le bypass gastrique.

Obesity is a chronic disease with a need for long-term follow-up. Bariatric surgery is very beneficial for patients who are not able to lose weight by lifestyle modifications alone. However, some patients present a weight regain after surgery. Predictive factors for the evolution of weight loss after bariatric surgery are not available today. For that reason, all preventive and therapeutic facilities should be used in order to reduce the risk of relapse after surgery. A recently introduced multidisciplinary therapeutic program for preparation of patients before bariatric surgery could be very valuable for a sustainable change of their lifestyle in order to minimize the risk of weight regain in the years after surgery.