BARIATRIC SURGERY AND TREATMENT OF TYPE 2 DIABETES Bradley Schwack, MD Assistant Professor, Surgery NYU School of Medicine NYU Weight Management Program BARIATRIC SURGERY Definition of obesity determined by height and weight Body Mass Index (BMI)= kg/m2 100 lbs overweight Degrees of Obesity NORMAL BMI 18.5 – 24.9 OVERWEIGHT BMI 25 – 29.9 OBESE BMI 30 – 34.9 SEVERE OBESE BMI 35 – 39.9 MORBIDLY OBESE BMI 40 What does it mean to be obese? Medical Implications: hypertension hyperlipidemia diabetes mellitus respiratory insufficiency obesityhypoventilation sleep apnea asthma cardiomyopathy/MI GERD PE/DVT CVA stress incontinence DJD wt-bearing joints low back pain venous stasis/ulcers cholelithiasis amenhorrhea infertility problems skin infections/inflammation accident proneness - cancer (uterus, breast, colon, prostate) Obesity is a U.S. public health epidemic: 64% Americans overweight 30% Americans obese 10% morbidly obese 400,000 deaths /year from obesity related causes [90,000 deaths/yr from colon + breast ca] #2 cause of preventable deaths #1 is smoking Bariatric Surgery Bariatrics: The study of Obesity and its Treatments Surgery: The science of operations Bariatric surgery: A therapeutic intervention to understand and treat the cause and sequelae of morbid obesity. Rising Use of Weight Loss Surgery Steinbrook, N Engl J Med, 2004 Bariatric Surgery and Diabetes Meta-analysis (Buchwald et al – 2009) Overall remission rate of 78% < 2 years since surgery 80% >2 years since surgery 75% Results seen with all operations, yet most dramatic with the gastric bypass Not much data beyond 5 years **If treated within 5 years of DM diagnosis— higher long term remission rates (Brethauer et al, 2013) – possible progressive loss of beta cell function Bariatric Surgery and Diabetes International Diabetes Federation (2011) Journal of Diabetes (3(2011): 261-264) “Bariatric surgery is an appropriate treatment of people with T2D and obesity who are not achieving recommended treatment targets with existing medical therapies, especially in the presence of other major comorbidities” <1% of those eligible actually have WLS for diabetes What do you do when you have 100 lbs to lose? 1991 NIH Consensus Statement Bariatric Surgery At BMI 40: risk of surgery < risk of morbid obesity CONSENSUS STATEMENT* Bariatric Surgery for Morbid Obesity: Health Implications for Patients, Health Professionals, and Third-Party Payers H. Buchwald, J Am Coll Surg 2005; 200:593 Criteria for surgery BMI > 40 kg/m2 -ORBMI > 35 kg/m2 and major medical complications of obesity -AND Failure of other approaches to long-term weight loss no substance abuse, psychoses or uncontrolled depression How does surgery work? Restrictive - restrict amount of food ingested Decreases appetite/hunger Early satiety Behavior modification Malabsorptive- limits digestion and absorption Decreases length of intestine exposed to digested food 25% of fat is absorbed Behavior modification Gastric Banding (Lap Band) Roux-en Y Gastric bypass (RYGB) Sleeve Gastrectomy Biliopancreatic Diversion, Duodenal Switch (BPD/DS) All operations can be performed open or laparoscopically Laparoscopic Roux en Y Gastric Bypass Laparoscopic Roux en Y Gastric Bypass 1960s invented by Drs. Mason and Ito Restrictive: small gastric pouch (15-20cc) Intestinal anatomy: Redirect the alimentary tract so that the gastric contents are directed 75-150cm distal to the ligament of Treitz . Redirection of intestines has 2 fold impact: Avoid the reflux of bile and pancreatic juices into the gastric pouch Variable malabsorbtive effect. -Gastric pouch: 15-20 ml •Food bypasses 95% stomach and duodenum •2 anastomoses •12 mm stoma •Inaccessible gastric remnant •Require life-long vitamin supplements •Side effects: •dumping, •stomal stricture •Deficiencies- iron, calcium •Theoretically reversible, but very difficult. Gastric Bypass The gastric bypass has been a recognized treatment of morbid obesity for over 40 years. Laparoscopic: 1994 Wittgrove and Clark 5-6 small abdominal incisions (0.5-2.0cm) Inflate the peritoneal cavity with gas to create space to work Reduces trauma, operative exposure, surgical insult, and postoperative pain. Proven an equally safe and effective means of weight loss. Level of comfort with procedure is a matter of surgeon opinion, training, and experience. Wittgrove et al. 1994 Higa et al., 2001. Lugan et al, 2004. Gastric Bypass Gastric Bypass 1.5-2 years 60-68% excess weight loss Majority of weight loss in first 9 months Plateau at 1.5 years 5 years may regain 15%-20% excess wt Gastric Bypass Complications Pneumonia Blood clots in legs Bleeding Infection Perotinitis intestinal leakage (2-3%) Popped staples Death: 1 in 200 Nutritional Risks Lifelong vitamins (Calcium, Fe, B-12) Daily multivitamin Bi-annual labs Watch for anemia Wait >18months before pregnancy Dehydration Bypass and Diabetes Pories et al (1995)-Greenville, NC (ECU) >600 patients 83% w/ T2DM—normal glc, HbA1c, insulin 99% w/ glc intolerance—normal “No other therapy has produced such durable and complete control of diabetes mellitus.” Ann Surg (1995; 222: 339-52) Bypass and Diabetes Bypass shows more promising resolution of diabetes than the sleeve or band. Parikh et al (2013)—Meta-analysis (1389pts) Remission rates (1 year): 33% Lap band 54% Sleeve 64% Gastric Bypass Buchwald et al (2009) Resolution of T2DM 57% Lap band patients 80% Gastric bypass patients Bypass and Diabetes Unique to bypass—DM resolution can come before weight loss Rubino et al (2006) – animal studies Bypassing a short segment of proximal intestine directly ameliorates T2DM, independent of food intake, body weight, etc. Potentially undiscovered factors from proximal small bowel contributing to pathophysiology of DM Bypass and Diabetes Theories as to “why” (and factors unique to bypass?) Weight loss Ghrelin suppression (bypassed stomach) Metabolic due to exclusion of the proximal small intestines (unsure of reasons why) Sleeve Gastrectomy Sleeve Gastrectomy Purely restrictive Partial gastrectomy of greater curvature Leaves tube of stomach sized to 32 French Bougie No long term data Sleeve Gastrectomy 1-2% risk of leak at upper stomach from staple line Possible re-operation Death Lengthy hospitalization Possible re-operation for completion Gastric bypass or malabsorbtive procedure Lap Band Re-sleeve gastrectomy Sleeve Gastrectomy and Diabtes “New Kid on the Block” Mechanism most likely related to acute weight loss ? Ghrelin suppression No part of GI tract is bypassed Sleeve Gastrectomy and Diabetes Sleeve has been done as a primary operation for a few years Small studies showing improvement of diabetes with weight loss Some show equal remission to and some show a bit less remission than with bypass Factors may be higher vs lower BMI Insulin insensitivity vs low insulin production The Laparoscopic Adjustable Gastric Band System A silicone band is placed around the upper part of the stomach A small pouch is created Slows down gastric pouch emptying Early feeling of satiety Surgical appetite suppressant Purely restrictive Quick recovery Adjustable restriction through mediport Reversible (if necessary) Depends on surgeon and patient commitment (much f/u) LAP-BAND Adjustability Unfilled Band Filled Band Adjustments are made in the office % Excess Weight Loss 90 80 70 60 LapBand 50 GB 40 BPD 30 20 10 0 0 1 yr 2 yrs 3 yrs 4 yrs 5 yr 1 Pories 1995 2 Marceau, 1998; Hess 1998; Scopinaro 1998 3 O’Brien 1999; Cadiere 2000; Fielding1999; Dargent 1999; Belachew 1998 Advantages Disadvantages No intestinal surgery No stapling/cutting of stomach No nutritional risks Adjustable Reversible Safe Foreign body Frequent follow-up visits Needs more commitment Easy to cheat Complications of the Band Slippage (5%)—gastric prolapse Erosion (0.1%)—band erodes into lumen Antibiotics Weight loss failure (5%) Replace in day surgery Port infection (0.5%) Need laparoscopic removal Tubing breakage (1%) Need reoperation laparoscopically Remove laparoscopically and do a RNY Death: 1 in >3000 LAGB and Diabetes Dolan and Fielding. Obes Surg, 2004 88 patients, BMI 45, Type II DM 2 years after surgery 51% EWL 65% patients off all medications (insulin, oral) 30% EWL by 6 months after surgery--> more likely to be off all DM medications Lap Band and Diabetes Sultan et al (2010: SOARD 6:373-376.) 102 patients LAGB (5 year mean EWL 48.3%) 88% preop on meds for DM, 46.5% on @5yrs 14.9% preop on insulin for DM, 8.5% @ 5yrs HbA1c: 7.53 avg preop; 6.58 avg 5 yrs later DM resolved—no meds, glc, HbA1c—in 40% of LAGB 5 years out Combined improvement/remission rate was 80% at 5 years Lap Band and Diabetes Dixon et al (2012: Obesity Reviews 13:5767) Remission improvement rates varied from 5370% within 2 years after LAGB placement Look at success of weight loss in lap band populations as well Varied results Surgery Deters Progression of Illness Incidence (%) 50 45 40 35 30 25 20 15 10 5 0 49 41 29 27 24 24 22 Control 17 8 8 7 1 2 YR 10 YR DM Sjöström et al., NEJM 2004,352:2683 2 YR HTN 10 YR 2 YR TG 10 YR Surgery Surgery Decreases Long-term Mortality Study Mortality with Surgery Mortality without Surgery MacDonald, 1997 9% 28% Christou, 2004 0.7% 6.1% O’Brien, 2006 0.3% 10.6% Restrictive Bariatric Surgery A tool against obesity Not a magic bullet Patient follow up and compliance is necessary Restrictive Bariatric Procedures and Diabetes BARIATRIC PROCEDURES HAVE BEEN SHOWN TO BE SUPERIOR TO CONSERVATIVE THERAPY IN THE MANAGEMENT OF TYPE 2 DIABETES Schauer et al (2012: N Engl J Med 366: 15671576) Dixon et al (2011: SOARD 7: 433-447) “Internation Diabetes Federation taskforce” The Conclusion. . . .? Type 2 Diabetes BMI < 35 Moderate response to conservative/medical treatment Will Bariatric Surgery be a treatment option and will insurance companies cover such a procedure?? This is not necessarily the goal of Bariatric Surgeon The Goal is to be Healthy 55 – 70% of the excess weight off Feeling less tired and sick Off high blood pressure meds Control and possible remission of Diabetes