The Changing Shape of Bariatric Surgery

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1 Measuring Obesity The Changing Shape of Bariatric Surgery D. Scott Diamond, MD FACS Determined by height and weight Comparison to ideal body weight/height BMI = weight(kg) height(m) 2 BMI = weight(lb)* 703 height(in) 2 Various Levels of BMI 1985 Normal Weight (BMI 19 to 24.9) What does obesity look like? *based on female 5 4 tall Overweight Obese (Class I) (BMI 25 to 29.9) (BMI 30 to 34.9) Obese (Class II) (BMI 35 to 39.9 ) Morbidly Obese (BMI 40 or more) 130# BMI # BMI # BMI # BMI # BMI 40 No Data <10% 10% 14% Agency for Healthcare Research and Quality. Screening for obesity in adults. Accessed June 22, 2010 from Dugdale DC. Obesity. MedlinePlus. Accessed June 22, 2010 from No Data <10% 10% 14% No Data <10% 10% 14% 15% 19%

2 % 14% 15% 19% 10% 14% 15% 19% 20% 2000 Obesity Trends* Among U.S. Adults % 14% 15% 19% 20% 10% 14% 15% 19% 20% 24% 25% % 19% 20% 24% 25% 15% 19% 20% 24% 25%

3 2008 Obesity Does Not Discriminate No Data < 10% 10%-14% 15%-19% 20%-24% 25%-29% 30% Prevalence of obesity, diabetes, and obesity-related health risk factors Mokdad AH, Ford ES, Bowman BA, et al 2003;289:76-79 Increases in obesity and diabetes among US adults continue in both sexes, all ages, all races, and all educational levels An Epidemic Within an Epidemic The Future is Now Children Age % obese % obese Adolescents % obese % obese Sturm R. Increases in morbid obesity in the USA: Public Health (2007) 121, Comorbidities (The diseases that accompany obesity) Metabolic Syndrome/Syndrome X Diabetes High Blood Pressure High Cholesterol Heart disease Asthma Sleep apnea Gallstones Liver Swelling (NASH) Urinary incontinence Acid reflux Arthritis and gout Infertility and menstrual problems High Risk Pregnancy Blood Clots Depression Immobility Cancer Breast Colorectal Prostate Endometrial Accident proneness Constellation of metabolic disorders Increase Risk Of cardiovascular disease Major features Central Obesity Hypertriglyceridemia Low HDL Hyperglycemia Hypertension

4 Metabolic syndrome Metabolic syndrome Estimated in 47 million US adults 1 Central Morbid Obesity Identified by the presence of 3 or more of the following: 2 Elevated waist circumference ( 102 cm men or 88 cm women) Elevated triglycerides ( 150 mg/dl or drug treatment) Reduced HDL-C (< 40 mg/dl men, < 50 mg/dl women or drug treatment) Elevated blood pressure ( 130 mm Hg systolic or 85 mm Hg diastolic or drug treatment) Elevated fasting glucose ( 100 mg/dl or drug treatment) Insulin Resistance Hyper-Insulinemia Dyslipidemia Type 2 Diabetes Hypertention Heart Disease 1 National Institutes of Health. What is metabolic syndrome? Revised January Accessed May 17, 2010 from 2 Grundy SM, Cleeman JI, Daniels SR, et al. Diagnosis and Management of the Metabolic Syndrome: An American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement: Executive Summary. Circulation. 2005; 112:e285-e290. Adapted from Lee YH, Pratley RE. The evolving role of inflammation in obesity and the metabolic syndrome. Curr Diab Rep. 2005;5:70-75 Prevalence of Metabolic syndrome Metabolic Syndrome & Inflammation Increases with Age Per National Health and Nutritional Examination Survey(NHANES) III 34% Men 35% Women Native Americans Nearly 60% women aged % men aged Proinflammatory cytokines increased IL-1,IL-6,IL-18,resistin,TNFα,CRP Increased production by adipose tissue derived macrophages Adiponectin decreased Anti-inflammatory cytokine/inhibits steps in inflammatory process Enhances insulin sensitivity In liver enhances expression of gluconeogenic ezymes and glucose production In muscle increases glucose transport, enhances fatty acid oxidation Metabolic Syndrome & Inflammation Metabolic syndrome/associated diseases Obesity is a chronic inflammatory state Increased Vascular reactivity Tilt toward a thrombotic state Fibrinogen, Plasminogen activator inhibitor 1 Decreased insulin sensitivity Increased sympathetic nervous activity Cardiovascular disease 1.5-3X relative risk in absence of diabetes Type 2 Diabetes 3-5X Nonalcoholic Fatty Liver Disease Hyperuricemia Obstructive Sleep Apnea

5 Medical Therapy for Obesity What Are Realistic Expectations? An optimal and continuous program which uses - Medications - Behavior modification -Diet -Exercise can be expected to achieve and maintain a weight loss of 20 pounds if continued permanently Treating Obesity Diet and exercise Behavior modifications Weight loss programs Appetite suppressants Hypnosis, jaw-wiring, counseling % Remaining in program High Attrition Rates of Commercial Weight Reduction Programs Comparison of Atkins, Ornish, Weight Watchers, and Zone Diets Randomized trial of 160 patients with average BMI of 35 (enrollment 2000 to 2002) Medically supervised Each diet reduced the LDL/HDL ratio by 10 percent Type of Diet Completing One Year Weight Loss at One Year Weeks after commencement of program Atkins 21/40 (53%) 2.1 kg (4 lbs.) Zone 26/40 (65%) 3.2 kg (7 lbs.) Weight Watchers 26/40 (65%) 3.0 kg (6 lbs.) Ornish 20/40 (50%) 3.3 kg (7 lbs.) Dansinger ML, Gleason JI, Griffith JL, et al. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease reduction. JAMA 2005;293(1) Atkins is a registered trademark of Atkins Nutritionals, Inc. Weight Watchers is a registered trademark of Weight Watchers International, Inc. Very Low Calorie Diet +/- Behavioral Modification Weight change (kg) Very-low-calorie diet Modified diet plus behavior therapy Very-low-calorie diet plus behavior therapy According to the NIH 1993 Surgery is the most effective option in achieving sustained weight loss in the morbidly obese patient population. -20 intervention Years after intervention

6 Roux-en Y Gastric Bypass Gastric Bypass Gastric pouch: ml Stomach holds less food Induces feeling of satiety Small opening in pouch Gastric remnant not removed Theoretically reversible, but very difficult Advantages Rapid initial weight loss Minimally invasive approach is possible Longer experience Minimal diet restrictions Dumping syndrome limits sugar intake Less follow-up required No foreign body implanted Disadvantages Anatomy is altered More operative complications than with LAGB Nonadjustable Reported higher mortality rate than LAGB/Gastric Sleeve procedures Extremely difficult to reverse Possibility of stretching pouch Laparoscopic Adjustable Gastric Band Laparoscopic Adjustable Gastric Band A silicone band is placed around the upper part of the stomach A small pouch is created Stomach holds less food Induces feeling of satiety OR time = 1 hour Overnight hospital stay Return to work in 1 week Evaluated every 6-8 weeks for gradual tightening if necessary Advantages Adjustable customized per patient Least invasive option No anatomic changes Removable Lowest operative complication rate rare leaks Low malnutrition risk Satiety-inducing procedure OR time = 1 hour or less Outpatient surgery sometimes possible Disadvantages Slower initial weight loss than gastric bypass Regular follow-up critical for optimal results Compliance is critical Foreign body Less long-term follow-up than bypass in US patients Erosion, slippage, infection Sleeve Gastrectomy Sleeve Gastrectomy No foreign body Weight loss comparable to other operations--gastric bypass, band No rearranging of intestines Disadvantage: NOT reversible--part of stomach permanently removed Not as good for patients with acid reflux/hiatal hernia

7 Long Term Results Gastric Bypass Mean Percent Weight Change during a 15-Year Period in the Control Group and the Surgery Mean Percent Weight Change during a 15-Year Period in the Group, According to the Method of Bariatric Surgery Control Group and the Surgery Group, According to the Method of Bariatric Surgery Sjostrom L et al. N Engl J Med 2007;357: Sjostrom L et al. N Engl J Med 2007;357: Weight Loss of Various Treatments for Morbid Obesity Treatment Lifestyle / Pharmacologic Treatments 1 (Diets, lifestyle programs, sibutramine, orlistat, rimonabant) Excess Weight Loss <10%* Laparoscopic Adjustable Gastric Banding 2 48% Sleeve Gastrectomy 3 55% Gastric Bypass Surgery 2 62% Appetite Control Hormones Important in metabolism, appetite, and satiety regulation. Hormones made by the cells in the stomach and intestines act on the brain. Regulate body weight by controlling appetite (ghrelin), satiety (PYY,CCK), and body metabolism (leptin, melanocortin). * Average Weight Loss from baseline; meta-analysis of various studies up to 4 years in length. 1 Bray GA. Lifestyle and pharmacologic approaches to weight loss: Efficacy and safety. J Clin Endocrinol Metab, 2008; 93(11): Buchwald H, Avidor Y, Braunwald E et al. Bariatric surgery: A review and meta-analysis. JAMA 2004; 292(14): Meta-analysis of studies with at least 30 days of follow-up, with the majority of followup at two years or less. 3 Brethauer SA, Hammel JP, Schauer PR. Systematic review of sleeve gastrectomy as staging and primary bariatric procedure. Surg Obes Relat Dis. 2009;5: Meta-analysis of studies from 3 to 60 months followup. Cummings DE, Schwartz MW. Genetics and pathophysiology of human obesity. Annu Rev Med 2003;54: Ghrelin Peptide YY Hormone secreted predominantly by gastric cells,upper intestine cells; recognized in 1999 as a mediator of growth-hormone release 1 Increases an hour or two before a meal and goes into a trough-like level after eating 2 Weight loss of 17 percent of body weight from dieting is associated with a 24 percent increase in the 24-hour ghrelin profile 2 Weight loss of 36 percent of body weight following gastric bypass surgery resulted in a 77 percent decrease in ghrelin levels from normal-weight controls and a 72 percent decrease in matched obese controls 2 Activated by the presence of dietary lipids 3 1. Kojima M, Hosoda H, Date Y, et al. Ghrelin is a growth-hormone-releasing acylated peptide from stomach. Nature 2009; 402: Cummings DE, Weigle DS, Frayo RS. Plasma ghrelin levels after diet-induced weight loss or gastric bypass surgery. NEJM 2002 May 23;346(21): Kirchner H, Gutierrez JA, Solenberg PJ, et al. GOAT links dietary lipids with the endocrine control of energy balance. Nature Medicine. 2009; 15(7): Released by intestinal endocrine L-Cells of distal gut Released in proportion to calories ingested Inhibits gastric, pancreatic and intestinal secretions and gastric motility Promotes satiety Increased secretion following malabsorbtive procedures Roux-En-Y and BPD Probably from gut hypertrophy(weight regain?)

8 Leptin/CCK Melanocortin Cholecystokinin Inhibits gastric Motility Induces feeling of satiety Not affected by surgery Leptin Released by adiposites As fat stores rise leptin rises, signaling we have enough to eat Obese people have high leptin levels Resistance to their actions Levels fall after surgery increasing satiety, decreasing hunger Melanocortin-4 receptor gene (MC4R) variants are associated with obesity and binge-eating disorder (BED) 300 patients (233 women, 67 men) with a mean BMI of 43.5 and a mean age of 42 Laparoscopic Adjustable Gastric Banding 36-month follow-up All MC4R patients had BED, compared to 18 percent in noncarriers MC4R patients showed less weight loss and five times more gastric complications 1. Potoczna N, Branson R, Kral JG, et al. Gene variants and binge eating as predictors of comorbidity and outcome of treatment in severe obesity. J Gastrointest Surg 2004;8: " Other Appetite Control Hormones Other Appetite Control Hormones GLP-1 Secreted by lower intestinal endocrine L cells to induce satiety Glocoregulatory improves glycemic control by inhibiting glucose dependent inhibition of glucagon secretion Slows gastric emptying Enteroglucagon Family(GLP-1,GLP-2, oxyntomodulin) Distal intestinal L cell secretion IV infusions decrease hunger and calorie intake Increased in dumping syndrome Glucose-dependent Insulinotropic polypeptide(gip) Secreted within minutes of nutrient ingestion Promotes energy storage by inducing βcell proliferation Promotes increased bone formation through osteoblast formation Pancreatic Polypeptide Released by pancreas in response to food intake Decreases food intake and gastric emptying Increases energy expenditure Helps create negative energy balance Decreases Leptin produced in adipose cells Glucose-dependent Insulinotropic polypeptide(gip) Secreted within minutes of nutrient ingestion Promotes energy storage by inducing βcell proliferation Promotes increased bone formation through osteoblast formation Government Agencies and Scientific Societies that Endorse Bariatric Surgery As A Standard of Care for Severe Obesity BARIATRIC SURGERY Losing 50% to 70% of excess weight 1 may be just the beginning Centers For Medicare and Medicaid Services National Institute of Health US Department of Veteran Affairs US Department of Defense The Obesity Society American College Of Physicians American Diabetes Association American Dietetic Association American Association of Clinical Endocrinology Association for Metabolic and Bariatric Surgery American College of Surgeons Society for Surgery of the Alimentary Tract Society of American Gastrointestinal and Endoscopic Surgeons

9 Surgery and Diabetes/Insulin Resistance Why Risk Bariatric Surgery? Decrease in Fat mass with weight loss All procedures Roux-en-Y bypass most studies and accepted as best treatment for diabetes Sleeve gastrectomy newer but studies suggest it does as well Anti-inflammatory factor adiponectin increased post surgery Favorably impacts insulin resistance Helps remission/improvement of diabetic state Journal Title Who would have thought it? An operation proves to be the most effective therapy for adult-onset diabetes mellitus Authors Pories WJ, Swanson MS, MacDonald KG Y;vol:pp 1995;222: Key point Surgery is more effective than medical therapy in treating obesity related diabetes Surgery and Diabetes/Insulin Resistance ADA Position statement on diabetes care 1 : Bariatric surgery should be considered for adults with BMI 35 kg/m 2 and type 2 diabetes, especially if the diabetes is difficult to control with lifestyle and pharmacologic therapy. Patients with type 2 diabetes who have undergone bariatric surgery need life-long support and medical Effect of Bariatric Surgery On Comorbid Medical Conditions Condition % Resolved % Improved Diabetes Hypertension Sleep Apnea Hyperlipidemia Buchwald H, Avidor Y, Braunwald E, et al: Bariatric Surgery: A Systemic Review and Meta-analysis. JAMA 292:1724, American Diabetes Association. Standards of medical care for diabetes Diabetes Care. 32(S1); S13-S44. January Impact of Bariatric Surgery on Diabetes Impact of All Surgery Types and Gastric Bypass, in Specific on Diabetes TOTAL* GASTRIC BYPASS OUTCOME t (n/n) % [95%CI] t (n/n) % [95% CI] % Patients Diabetes Resolved 63 (1,846) 76.8 [70.7, 82.9] 26 (989) 83.7 [77.3, 90.1] Impact of Bariatric Surgery on Hypertension Impact of All Surgery Types and in Specific Gastric Bypass on Hypertension TOTAL* GASTRIC BYPASS OUTCOME t (n/n) % [95%CI] t (n/n) % [95% CI] HbA1C (%) Reduction (Diabetics)** 6 (171) -2.4 [-3.8, -1.0] 4 (88) -3.0 [-5.0, -1.1] Patients Hypertension Resolved 67 (4,805) 61.7 [55.6, 67.8] 20 (2,115) 67.5 [58.4, 76.5] Fasting Glucose (mmol/l)** 14 (296) -4.0 [-5.2, -2.7] 7 (164) -3.4 [-5.2, -1.7] Fasting Insulin (pmol/l)** 36 (1,460) [ ] 6 (93) [ ] THE MAJORITY OF MORBIDLY OBESE DIABETICS EXPERIENCE RESOLUTION OF DIABETES AFTER BARIATRIC SURGERY * Total All bariatric procedures including gastric bypass surgery, Vertical Banded Gastroplasty (VBG), Laparoscopic Adjustable Gastric Banding, Biliopancreatic Diversion, and Duodenal Switch; Normal Ranges: HbA1c < 6.0 percent, Fasting glucose = mmol/l, Fasting insulin = pmol/l t = number of studies or treatment groups; n = number of patients with this characteristic; N = number of patients evaluated; Diabetes resolved Numerator = discontinued treatment or condition disappeared; denominator includes patients evaluated for resolution. Buchwald H, Avidor Y, Braunwald E, et al. Bariatric Surgery A Systematic Review of the Literature and Meta-analysis. Journal of the American Medical Association 2004 Oct 13;292(14). HYPERTENSION IS RESOLVED OR IMPROVED IN MOST PATIENTS FOLLOWING BARIATRIC SURGERY * Total All bariatric procedures including gastric bypass surgery, Vertical Banded Gastroplasty (VBG), Laparoscopic Adjustable Gastric Banding, Biliopancreatic Diversion, and Duodenal Switch. t = number of studies or treatment groups; n = number of patients with this characteristic; N = number of patients evaluated; Hypertension resolved numerator = discontinued treatment or condition disappeared; denominator includes patients evaluated for resolution. Buchwald H, Avidor Y, Braunwald E, et al. Bariatric Surgery A Systematic Review of the Literature and Meta-analysis. Journal of the American Medical Association 2004 Oct 13;292(14).

10 Surgery and Diabetes/Insulin Resistance Sleeve Vs. Roux-En-Y Decrease in Fat mass with weight loss All procedures Roux-en-Y bypass most studies and accepted as best treatment for diabetes Sleeve gastrectomy newer but studies suggest it does as well Anti-inflammatory factor adiponectin increased post surgery Favorably impacts insulin resistance Helps remission/improvement of diabetic state Sleeve Gastrectomy Roux En Y Bypass Total Cholesterol 75% 100% Improvement/resolution Resolution of 64.3% 74.4% Hypertension Remission of Diabetes 96% 85.7% Benaiges D, Goday, A, Ramon, JM, Hernandez E, Pera M, Cano, JF: Laparoscopic Sleeve Gastrectomy and Laparoscopic Gastric Bypass Are Equally Effective for Reduction of Cardiovascular Risk in Severely Obese Patients at One Year Follow-up. Surgery for Obesity and Related Diseases; 7(2011): Methods: Study Design Sleeve Vs. Roux-En-Y Observational two-cohort study Subjects: 1,035 morbidly obese patients treated with bariatric surgery at the McGill University Health Centre, Montreal Controls 5,746 matched morbidly obese patients who had not undergone surgery Controls matched for age, BMI, date of first diagnosis of M/O, gender, and disease status Inception time for bariatric cohort was surgery date. Inception time for controls was date of surgery of their match Christou NV, Sampalis JS, Liberman M, et al. Surgery Decreases Long-Term Mortality, Morbidity, and Health Care Use in Morbidly Obese Patients. Annals of Surgery 2004;240(3): Sleeve Gastrectomy Roux En Y Bypass Total Cholesterol 75% 100% Improvement/resolution Resolution of 64.3% 74.4% Hypertension Remission of Diabetes 96% 85.7% Benaiges D, Goday, A, Ramon, JM, Hernandez E, Pera M, Cano, JF: Laparoscopic Sleeve Gastrectomy and Laparoscopic Gastric Bypass Are Equally Effective for Reduction of Cardiovascular Risk in Severely Obese Patients at One Year Follow-up. Surgery for Obesity and Related Diseases; 7(2011): Impact of Bariatric Surgery on Hyperlipidemia Impact of All Surgery Types and in Specific Gastric Bypass on Hyperlipidemia TOTAL* GASTRIC BYPASS OUTCOME t (n/n) % [95%CI] t (n/n) % [95% CI] % Patients Improved Hyperlipidemia 23 (846/1,019) 79.3 [68.2, 90.5] 6 (125) 96.9 [93.6, 100.0] Hypercholesterolemia 14 (2,051) 71.3 [55.5, 87.0] 5 (439) 94.9 [90.7, 99.1] Hypertriglyceridemia 11 (983) 82.4 [71.1, 93.7] 4 (271) 91.2 [83.6, 98.8] Total Cholesterol (mmol/l) 36 (2,573) -0.9 [-1.1, -0.6] 7 (307) [-1.2, -0.8] HDL Cholesterol (mmol/l) 30 (2,003) 0.1 [-0.0, 0.1] 6 (163) 0.05 [-0.1, 0.2] LDL Cholesterol (mmol/l) 21 (879) -0.8 [-1.1, -0.5] 5 (81) [-1.2, -0.6] Triglycerides (mmol/l) 34 (2,149) -0.9 [-1.1, -0.7] 7 (304) [-1.5, -0.7] HYPERLIPIDEMIA AND HYPERCHOLESTEROLEMIA IMPROVE IN MOST PATIENTS FOLLOWING BARIATRIC SURGERY * Total All bariatric procedures including gastric bypass surgery, Vertical Banded Gastroplasty (VBG), Laparoscopic Adjustable Gastric Banding, Biliopancreatic Diversion, and Duodenal Switch. t = number of studies or treatment groups; n = number of patients with this characteristic; N = number of patients evaluated; Patients Improved numerator includes patients described by study authors as having improved by virtue of elimination or reduction in therapy and patients reported to have improved lipid parameters. Buchwald H, Avidor Y, Braunwald E, et al. Bariatric Surgery A Systematic Review of the Literature and Meta-analysis. Journal of the American Medical Association 2004 Oct 13;292(14). Baseline Cohorts Baseline Characteristics BARIATRIC CONTROLS Number of Subjects 1,035 5,746 Mean Age (SD) 45.1 (11.6) 46.7 (13.1) Male Gender N (%) 356 (34.4%) 2,068 (36.0%) Mean Follow-up (SD) 2.5 (1.4) 2.6 (1.5) Christou NV, Sampalis JS, Liberman M, et al. Surgery Decreases Long-Term Mortality, Morbidity, and Health Care Use in Morbidly Obese Patients. Annals of Surgery 2004;240(3):

11 Significant Relative Risk Reduction in Morbidity and Mortality at Five Years Reduction in Incidence of Co-morbidities at Five Years 5-Year Mortality Reduction Surgical Patients had Nine Times Lower Mortality Rate within the Study Period * p < * Includes perioperative (30-day) mortality of 0.4% p-value Christou NV, Sampalis JS, Liberman M, et al. Surgery Decreases Long-Term Mortality, Morbidity, and Health Care Use in Morbidly Obese Patients. Annals of Surgery 2004;240(3): Christou NV, Sampalis JS, Liberman M, et al. Surgery Decreases Long-Term Mortality, Morbidity, and Health Care Use in Morbidly Obese Patients. Annals of Surgery 2004;240(3): Reduction in Healthcare Utilization Five-Year Healthcare Utilization BARIATRIC MEAN (SD) CONTROLS MEAN (SD) P-VALUE Hospitalizations 2.75 (3.44) 3.17 (3.22) Hospital Days (38.97) (25.41) Physician Visits 9.62 (15.8) (21.74) Christou NV, Sampalis JS, Liberman M, et al. Surgery Decreases Long-Term Mortality, Morbidity, and Health Care Use in Morbidly Obese Patients. Annals of Surgery 2004;240(3): Summary Similar to the above study, there are multiple others demonstrating that bariatric surgery is safe with a lower mortality rate than the general morbidly obese population. Bariatric surgery patients have a lower mortality rate in the long-term follow-up. Bariatric surgery patients have significant risk reductions for developing all major categories of chronic, inflammatory conditions. Surgery patients had significantly fewer hospitalizations, inhospital days, and outpatient physician visits.. Direct healthcare costs are significantly lower in the surgery cohort with surgical costs recovered within 2 years.