Post-operative bed and anhedonia may affect bariatric surgery results: a prospective study

Obesity is a severe disease with a decreased life expectancy and impaired quality of life. Bariatric surgery leads to long-term weight loss and improvement of psychiatric and medical comorbidities, even after accounting for weight regain. Although several researches have explored possible pre-operative psychiatric predictors of weight loss, results were inconsistent. There is a growing interest in understanding how psychological post-operative factors may influence weight loss. Data identifying the predictive validity of post-operative psychiatric features are still lacking. Binge eating disorder (BED) was associated with weight loss with mixed results. Anhedonia is a core symptom of depressive disorder and is related to a reduced feeling of pleasure from activities previously found enjoyable. Few studies have explored the relationship between anhedonia and eating disorders. The purpose of this study was to explore whether post-operative binge eating disorder (BED) and anhedonia can be used to predict outcome of bariatric surgery. Methods A group of 105 individuals, 36 % men and 64 % women, with a mean age of 45 (range 20–65) underwent a psychiatric counselling before and 1 year after bariatric surgery. Weight loss after surgery was measured with %EWL. Results One-way ANOVA showed significant lower %EWL at 1 year in those with a preoperative psychiatric disorder (F (1103) = 3,7696, p = 0.5). Regression analysis showed that post-operative BED (p.001) and anedhonia (p = 0.03) were significant and independent predictors of lower %EWL after surgery (AdjR2 .29, p.0001). Conclusions The presence of post-operative BED significantly predicted poorer weight loss at 1 -year follow-up. We found that the presence of anhedonia, regardless of whether the participant had BED, significantly predicted poorer weight loss at 1 -year follow-up. Post-operative anhedonia may represent a trigger leading to the development of maladaptive eating behavior, higher consumption of palatable food, with poorer outcome in terms of weight loss or may constitute a risk factor itself.