1. Bariatric surgery: an effective ‘psychotherapy’ for food addiction David Schroeder Surgical Obesity Service Hamilton/Wellington

2. Disadvantages: Cutting and stapling of stomach & bowel and portion of digestive track is bypassed Reduced absorption of essential nutrients Side effects due to malabsorption Nonadjustable More operative complications Higher mortality rate than LAP-BAND® procedure Advantages: Rapid initial weight loss Can be done via keyhole approach Almost immediate improvement in Type II Diabetes REY Gastric bypass

3. Sleeve Gastrectomy

5. Adjustable gastric banding A silicone band is placed around the upper part of the stomach A small pouch is created Induces variable feeling of satiety: ‘not hungry’ Evaluated every 2-6 weeks initially for gradual tightening if necessary Disadvantages Slower initial weight loss than gastric bypass Regular follow-up critical for optimal results

6. 43 Possible Complications-Death 0% General operative risks bleeding, liver or spleen damage, infection, etc- <1% blood clots- 0% Band specific: Complications of the band: Slippage - 2% Erosion- 0.5% Complications of the port: Infection-0.5% Tilting, Damage-1%

7. 43 Possible Complications REYGB and sleeve gastrectomy specific: Leak - 0.16% Bleeding higher than banding- 1% Stricture - 3% Longterm REYGB: Vitamin deficiency- everyone who doesn’t take supplements Ulcers- 1% Bowel obstruction 2%->0% Gallstones- 12% 1212%

8. Mechanisms of surgery Bypass- probably hormonally mediated decrease in insulin resistance and increase in satiety Band- probably vagus nerve mediated increase in satiety Sleeve- probably mixture but decreased ghrelin

9. Effects of surgery on hormonal release Gut peptidesCentral effects on appetiteAlterations due to RGB Ghrelin PPY GLP-1 CCK Insulin Leptin

10. Psychology of addiction Nucleus accumbens Prefrontal cortex- inhibited by depression tiredness alcohol smoking BMI Neocortex

11. CNS Upregulation of D2 receptors Activation of hippocampus related satiety centres via vagus nerve Changes in reward centre responses to energy dense foods

12. Are these changes universal & permanent? Sometimes Major business in US to help people who have regained weight after REYGB Some can lose only 4-20 kg in a year Blame placed on operation or patient: pouch dilatation, stoma enlargement

14. Non-hungry eating Revert to old ways of eating: high carb, low protein Ignoring satiety Not changing habits Reactivation of cravings by memory Losing motivation to keep going Expectations not met Not telling people they have had surgery Why?

15. % excess weight loss after LREYGB With wrap around Without wrap around

16. Surgery does offer an effective way to switch off food addiction We are not sure of the mechanisms The results are very variable Maximum effect is in the first year- variable thereafter We can improve outcomes by understanding the mechanisms of addiction & encouraging self-care It is as safe as gallbladder surgery It is expensive short term, but saves money in the long term