Obesity Surgery : Is it only for losing weight ? Joint Hospital Surgical Grand Round Simon Chu Prince of Wales Hospital

Obesity Classification WHO ClassAsian Underweight < 18.5 Normal 18.8 – 22.9 Overweight >23 Obese I >25 Obese II >30 Obese III N/a WHO guidelines 2005

Figures in Hong Kong Burden of Obesity – lessons learnt from Hong Kong Chinese Obesity Reviews (2008) 9 (Suppl. 1,) 35-40

Gastric Banding Reversibility Ability to calibrate Less destructive to stomach

Sleeve Gastrectomy Preserve normal food passage Second stage procedure is possible Serious complications

Gastric Bypass Most common procedures performed in U.S. Better long term outcome than pure gastric restrictive technique Persistent nutritional problems

Biliopancreatic diversion with duodenal switch Achieved best weight loss Possible for 2-stage procedure High operative complications

Intragastric balloon Artificial bezoar Increase in satiety  reduction of food intake Part of a diet programme Temporary procedure to aid further conventional intervention

1st element of assessing the efficacy of an bariatric surgery Where is the evidence of  GOOD WEIGHT REDUCTION = IMPROVEMENT OF CO- MORBIDITIES Meta-analysis : Surgical treatment of Obesity Ann Intern Med 2005; 142 :

Swedish Obese Subjects (SOS) Prospective non-randomized, interventional trial Patients undergo bariatric surgery vs conventionally treated patients Effects of weight loss on risk factors and hard end points Changes in cardiovascular risk factors over follow-up periods

Bariatric Surgery is a viable option for treatment of severe obesity as 1.Result in long term weight loss 2.Amelioration in risk factors

Another prospective study using the same group of patients published in 2007 To determine association between weight loss and mortality rate Study period : 10.9 years Weight loss from baseline : at least more than 15% Adjusted hazard ratio 0.76 surgery group New England Journal Of Medicine Vol 347, No 8 Aug 23, 2007

Apart from weight reduction…..

Apart from weight reduction Circulation 2004; 110 :

Asia patients : Abdominal obesity Men : 90cm Women : 80cm

Any help? Significant improvement in all parameters after gastric bypass surgery at post-operative 6 months Remission of Metabolic Syndrome : A study of 140 patients Six Months after Roux-en-Y Gastric Bypass Obesity Surgery ( 2008 ) 18: Gastric Bypass Surgery induces persistent and considerable improvement in MetS prevalence compared with patients treated conventionally Effect of Bariatric Surgery on the Metabolic Syndrome : A population based, Long-term Controlled Study Mayo Clinic Proceedings : Aug 2008 : 83, 8

JAMA 2008; 299 (3) : Unblinded randomized controlled trial 60 patients with BMI between 30 and 40 and recently diagnosed type 2 DM Conventional diabetes therapy vs laparoscopic adjustable gastric banding Outcomes : Remission of type 2 diabetes ( Fasting glucose < 7 mmol/L and HbA1c < 6.2% while not on glycemic therapy ) Diabetic Remission : 22/30 (73%) in surgical group 4/30 (13%) in conventional group at 2 years

The Future..

Metabolic Surgery Return to euglycaemia and normal insulin levels are observed within days after bypass surgery Weight loss alone cannot explain the association “ Rearrangement of gastrointestinal anatomy as a primary mediator of surgical control of diabetes ?“

Open questions for clinical Research Surgical treatment for Diabetes in patients 1.BMI < 30 ? 2.Or with normal BMI ?

Conclusion Bariatric Surgery is effective in promoting weight loss in morbid obesity which has a long lasting effect Effect of weight loss can be transferred to reduction in mortality rate Apart from weight loss, remission of metabolic syndrome and type 2 diabetes are the other clinical outcomes associated with bariatric surgery