Bariatric surgery: an Bariatric surgery: an effective effective

‘psychotherapy’ for ‘psychotherapy’ for food addictionfood addiction

David Schroeder

Surgical Obesity Service

Hamilton/Wellington

Disadvantages:Cutting and stapling of stomach & bowel and portion of digestive track is bypassedReduced absorption of essential nutrientsSide effects due to malabsorption NonadjustableMore operative complications Higher mortality rate than LAP-BAND® procedure

Advantages:Rapid initial weight lossCan be done via keyhole approachAlmost immediate improvement in Type II Diabetes

REY Gastric bypass

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

Sleeve Gastrectomy

Sleeve Gastrectomy

Adjustable gastric bandingA silicone band is placed around theupper part of the stomach

A small pouch is createdInduces variable feeling of satiety: ‘not

hungry’Evaluated every 2-6 weeks initially for

gradual tightening if necessaryDisadvantagesSlower initial weight loss than gastric

bypassRegular follow-up critical for optimal results

43

Possible Complications-Death 0%

General operative risksbleeding, 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%

43

Possible ComplicationsREYGB 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%

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

Mechanisms of surgeryBypass- 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

Effects of surgery on hormonal release

Gut peptidesCentral effects on appetite

Alterations due to RGB

Ghrelin

PPY

GLP-1

CCK

Insulin

Leptin

Psychology of addiction

Nucleus accumbens

Prefrontal cortex-inhibited by depressiontirednessalcoholsmokingBMI

Neocortex

CNSUpregulation of D2 receptorsActivation of hippocampus related satiety centres via vagus nerve

Changes in reward centre responses to energy dense foods

Are these changes universal & permanent?

SometimesMajor 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

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?

% excess weight loss after LREYGB

With wrap around

Without wrap around

Surgery does offer an effective way to switch off food addictionWe are not sure of the mechanismsThe results are very variableMaximum effect is in the first year- variable thereafterWe can improve outcomes by understanding the

mechanisms of addiction & encouraging self-careIt is as safe as gallbladder surgeryIt is expensive short term, but saves money in the long

term