1. Metabolic Effects of Bariatric Surgery on Diabetes Mr Paras Jethwa BSc MD FRCS FRCS(Gen Surg) Consultant Laparoscopic Surgeon

2. Definitions Body Mass Index = weight/height 2 < 20 = underweight 20-25 = normal 25-30 = overweight 30-40 = obese > 40 = morbidly obese Excess Weight = Current Weight – Ideal Weight

3. BMI > 301991

4. BMI > 301992

5. BMI > 301993

6. BMI > 301994

7. BMI > 301995

8. BMI > 301996

9. BMI > 301997

10. BMI > 301998

11. BMI > 301999

12. BMI > 302000

13. BMI > 30 2001

18. Obesity Related Mortality

19. Type 2 DM >80% have BMI >25 50% obese, 10%>40% Modest weight loss helps control BUT - 95% will fail with diet Proposed in mid 90’s that T2DM – “Surgical disease” – Foregut hormone stimulation

20. Surgical Options Restrictive vs. malabsorption Restrictive: – Generating saiety signals Malabsorpative: – Gastric restriction – Duodenal and upper jejunal bypass Extreme (BPD & Switch) – Only last 50cm of SB used for digestion

21. Laparoscopic Gastric Band Mean = 47% EWL Best for – BMI < 47 kg/m 2 – Regular meal patterns – Non sweet eaters Mortality risk 1:800 Morbidity risk 1:100 15% bands need revision

22. Laparoscopic Gastric Bypass Mean = 72% EWL Best for – All BMI – Sweet eaters and grazers – Diabetics Mortality risk 1:300 Morbidity risk 1:75

23. Laparoscopic Sleeve Mean = 75% EWL? Easy maintence One long suture line Poorer longterm Removes Ghrelin producing cells Mortality risk 1:400 Morbidity risk 1:100

24. Laparoscopic Mini Gastric Bypass Mean = 80% EWL Best for – All BMI – Grazers – T2DM Mortality risk 1:500 Morbidity risk 1:80 Lower long term risk of metabolic complications Extensively practiced in US

25. MGB success

26. What mechanisms are at work? Bypass factors Foregut vs. Hindgut theories – Gherlin – Glucagon like peptide – Gut derived glucadonotropic signalling Diabetic effect seen before weight loss – Clear division contributes – RYB vs. Banding for speed of control

27. Weight loss factors Improvements insulin action/reduced resistance Relieve secretory pressure on ß cells Early effect: – Calorific reduction - increase insulin sensitivity Later effect: – Absolute weight loss  glycaemic control

28. Are the effects longlasting? Maximum wt loss is at 1-2 years 30-50% excess wt loss at 6/12 10-14 years post op - more favourable levels of : – Cholesterol – DM – HT

29. Benefits 621 studies with 135, 246 patients Mean age - 40.2 years Mean BMI - 47.9 80% Female 56% EBWL 78% resolution of diabetes BPD>RYB>LAGB Effect static at 2 years

30. Case controlled prospective study Surgery v control 4047 patients 99.9% follow up Average 10.9 year follow up Prospective SOS trial: – Glucose/lipids/BP 10.9 year FU - 30%  mortality

31. Non T2DM effects SOS study 50% reduction in IHD 85% reduction in sleep apnoea Life expectancy improves up to 89% Up to 40% reduction in premature death 60% reduction in cancer deaths Fatal IHD halved

32. Resolution / improvement of comorbidities

33. Prognostic factors for DM remission Type of op Pro: – Early rapid weight loss – Preoperative insulin dose Against: – Diabetes dutation (B cell mass) – High HbA 1c – Insulin vs. oral therapy – Diabetic complications (retinopathy etc.) Unsure: – FH – Late onset type 1

34. Risks Remarkably safe Mortality 0.1% to BPD 1.1% 5-10% acute comps – Bleeds – Int. hernia – Anastomotic issues – Nutrition – Emotional Hypoglycaemia if medication unaltered

35. Metabolic Surgery  BMI > 40 or BMI >35 with Comorbidity  NICE: CG43  Exhausted non surg methods  Fit for op  Willing  First line for BMI>50  Part of MDT  In young in exceptional circumstances  psychological factors etc.

36. Diabetes Bypass: – Type 2 - 87% resolution Band – Type 2 - 73% resolution 92% mortality risk reduction Clinically and cost effective for moderate to severe obesity

37. Role of banding? RCT of 80 patients 2 year follow up 87% v 22% excess weight loss Significant reduction in metabolic syndrome

38. 50-77% of obese adolescents carry their obesity into adulthood

39. Adolescents Rapidly growing group in US – Sequential family members Extremely obese teen – Treatment of choice? Radical step BUT……. – T2DM not uncommon in teens now – Given that we are following US trends…

40. Summary Obesity plays a key role in pathophysiology Roux en Y bypass most effective Effects not just related weight related Useful adjunct in obesity esp. when DM difficult to control Surgical diversion leads to release of incretin Type 2 DM evaluated at MDT