Introduction/Aims: Currently, the most successful long term treatment for obesity is bariatric surgery, however the underlying mechanisms are not fully understood. Changes in gastrointestinal and central neuroendocrine signalling have been postulated as mediators of psychological and eating behaviour changes following bariatric surgery. We aimed to investigate changes in eating behaviour and psychological factors pre- and 1 month post-very low calorie diet (VLCD) and 3-month post Roux-en-Y gastric bypass surgery (RYGB).
Methods: Prospective study of 22 obese diabetic subjects recruited through the Imperial Weight Centre. 15 questionnaires classified into psychological factors, personality traits, eating behaviours, food hedonics, health-related quality of life and alcohol use, were completed by patients pre- and post-intervention. Results were analysed using two-way ANOVA followed by post-hoc analysis using the Bonferroni method. Data presented as mean ± standard deviation.
Results: VLCD group: 11 subjects (5 females) with BMI 39.4±5.2 kg/m2 and age 51.5±9.0 year.
○ Increase in restraint scores (P=0.0002).
RYGB group: 11 subjects (9 females) with BMI 40.4±4.3 kg/m2 and age 46.4±13.4 year.
○ Healthier eating patterns characterised by a reduction in eating in response to emotional and external food-related stimuli (P=0.0012) and reduced desire and impulsivity for novel rewards (P=0.0352)
○ Improvement in Physical Functioning (P=0.0625) and pain (P=0.0424)
○ Trend towards the improvement in anxiety and depression scales (P=ns)
No significant changes were found in alcohol following either intervention.
Conclusions: Quality of life improvement and eating behavioural changes were seen post-RYGB in contrast with the VLCD group, emphasising the effectiveness of surgical intervention in ameliorating obesity-related symptoms whilst providing substantial, long-lasting weight-loss effects. There was no significant change in psychological characteristics, food hedonics and alcohol use, although the study may have been underpowered to detect this. The changes in eating behaviour may be an important contributor to long term weight maintenance after RYGB. The increase in restraint among post-VLCD patients warrants further research using longer-term studies.