The Impact of a Preoperative Cognitive Behavioural Therapy (CBT) on Dysfunctional Eating Beahaviours, Affective Symptoms and Body Weight 1 Year after Bariatric Surgery: A Randomised Controlled Trial.

Background To examine whether a preoperative cognitive behavioural therapy (CBT) intervention exceeds usual care in the improvements of dysfunctional eating behaviours, mood, affective symptoms and body weight 1 year after bariatric surgery. Methods This is a 1-year follow-up of a single centre parallel-group randomised controlled trial (http://​clinicaltrials.​gov/​ct2/​show/​NCT01403558). A total of 80 (55 females) patients mean (SD) age 44 (10) years were included. The intervention group received 10 weeks of CBT prior to bariatric surgery, and the control group received nutritional support and education. Both groups were assessed at baseline (T0), post CBT intervention/preoperatively (T1), and 1 year postoperatively (T2). Using a mixed modelling statistical approach, we examined if the CBT group improved more across time than the control group. Results Our hypothesis was not supported as both groups had comparable improvements in all outcomes except for anxiety symptoms. Body weight declined by 30.2 % (37.3 kg) in the CBT group and by 31.2 % (40.0 kg) in the control group from baseline to follow-up, p = 0.82. There were statistically significant reductions in anxiety and depression symptoms in the CBT group between T0 and T1 and between T1 and T2 for depression only. However, in the control group, the anxiety score did not change significantly. The CBT group showed an earlier onset of improvements in all eating behaviours and affective symptoms than the control group. Conclusion The 10-week CBT intervention showed beneficial effects preoperatively, but the non-significant group differences postoperatively indicate a genuine effect of surgery