The Obesity Epidemic. John Ganser, MD, FACS Associate Professor UNSOM.

Transcription

1 The Obesity Epidemic John Ganser, MD, FACS Associate Professor UNSOM

2 The Obesity Epidemic - Outline Statistics of the Epidemic Magnitude of the problem Mechanisms of Obesity Metabolic Disease Comorbid conditions associated and their effect on mortality Effect of weight loss surgery on comorbid conditions and mortality Complications of bariatric surgery

3 Body Mass Index (BMI) Obesity is measured by a formula called body mass index (BMI) weight in kg/height m2. A healthy BMI is about A BMI of 30 or more signals obesity. A BMI of 35 or more reflects severe (morbid) obesity.

4 Body Mass Index (BMI) Body Mass Index (BMI) Measures obesity based on weight and height Weight Category BMI (kg/m 2 ) Healthy Weight Overweight Obese Severely Obese Morbidly Obese 40 Weight (lbs) Height (ft/in) Please note BMI does not distinguish between fat and muscle. A heavily muscled person could have a BMI in excess of 25 without having any increased health risks.

5 Classification of Obesity Clinical Terms Used to Describe Various Levels of Body Fat Normal Weight (BMI* 18.5 to 24.9) Overweight (BMI 25 to 29.9) Obese (Class I) (BMI 30 to 34.9) Obese (Class II) (BMI 35 to 39.9 ) Extremely Obese (Class III) (BMI 40 or more) * BMI (Body Mass Index): A measurement of an individual s weight in relation to height (kg/m 2 ). 1. National Institutes of Health/National Heart, Lung and Blood Institute Clinical Guidelines Evidence Report. NIH Publication , September 1998.

6 The Obesity Epidemic U.S. More than 69% of adults are overweight or obese 34.9% of U.S. adults are obese (BMI > 30) 78.6 million people 6.4% of adults are morbidly obese (BMI>40) 32% of children are overweight or obese (2-19) 17% are obese 365,000 obesity-related deaths occur annually NHANES National Health and Nutrition Examination Survey

7 The obesity Epidemic -Worldwide Global Burden of Disease Study 3.4 million deaths worldwide Worldwide increase 28.8% to 36.9% in men BMI>30 Worldwide increase 29.8% to 38.0% in women BMI >30 Prevalence in children 23.8% boys, 22.6% girls No nation has reported success in reducing the prevalence of obesity in 33 years The Lancet, Volume 384, issue 9945, P , 30 Aug 2014

8 The Obesity Epidemic Economic Impact Total medical cost for obesity $168 billion (1998 $78.5 billion) 9.1% of annual spending on medical care Individual annual medical cost $1,429 higher than normal weight (42% Increase) 80% higher prescription drug costs than for normal weight individuals

9 What Is Morbid Obesity? A chronic, life-threatening disease. Recognized as a disease by AMA in 2013 Excessive body fat accumulation resulting in a negative effect on health BMI > 35 kg/m 2 Risk factor for 30+ medical conditions. Medical, psychological, social, physical and economic impact.

10 Health Conditions Related Comorbidities Heart Disease Type 2 Diabetes Mellitus Hypertension Strokes Certain types of Cancer Endometrial Breast Prostate Colon Dyslipidemia Gallbladder disease Sleep apnea Asthma Reduced fertility Osteoarthritis

11 Comorbidities (continued) Low-back and disk disease Pulmonary emboli Obesity hypoventilation Pulmonary hypertension Gout Depression Urinary-stress incontinence Gastroesophageal reflux disease Liver and biliary gallstones Soft tissue infections Early death

12 Obesity Impacts Nearly Every Organ System Pulmonary disease abnormal PFTs obstructive sleep apnea hypoventilation syndrome Non-alcoholic fatty liver disease steatosis steatohepatitis cirrhosis Gall bladder disease Gynecologic abnormalities abnormal menses infertility polycystic ovarian syndrome stress incontinence Reference 5 Osteoarthritis Skin Gout Depression Stroke GERD Cardio/Metabolic Syndrome diabetes (80% type 2) dyslipidemia hypertension metabolic syndrome Severe pancreatitis Cancer (42% Breast/Colon) breast, uterus, cervix colon, esophagus, pancreas kidney, prostate Phlebitis venous stasis Premature Death

13 Fact An adult with a BMI of 35 or more has a 33% chance of living to age 65 as that of a normal weight person.

14 Relationship between BMI and Health Risk Diabetes Hypertension Sleep apnea Depression Joint pain Infertility Cancer GERD Asthma Calle EE, Michael MJ, Petrelli JM, et al. Body-mass index and mortality in a prospective cohort of US adults. N Eng J Med. 1999;341(15):

15 Relative Risk of Obesity Berrington de Gonzalez A, Hartge P, Cerhan JR, et al. (December 2010). "Body-mass index and mortality among 1.46 million white adults". N. Engl. J. Med. 363 (23):

16 Relative Risk of Obesity Berrington de Gonzalez A, Hartge P, Cerhan JR, et al. (December 2010). "Body-mass index and mortality among 1.46 million white adults". N. Engl. J. Med. 363 (23):

17 Prevalence of Self-Reported Obesity Among U.S. Adults by State and Territory The data were collected through the Behavioral Risk Factor Surveillance System (BRFSS), an ongoing, state-based, telephone interview survey conducted by state health departments with assistance from CDC. Obesity: Body Mass Index (BMI) of 30 or higher.

18 1985 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% Source: BRFSS, CDC

19 1991 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% Source: BRFSS, CDC

20 1993 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% Source: BRFSS, CDC

21 1996 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% Source: BRFSS, CDC

22 1999 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% 20 Source: BRFSS, CDC

23 2002 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% 20% 24% 25% Source: BRFSS, CDC

24 2004 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% 20% 24% 25% Source: BRFSS, CDC

25 2007 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person No Data <10% 10% 14% 15% 19% 20% 24% 25% 29% 30% Source: BRFSS, CDC

26 2010 Obesity* Trends Among U.S. Adults *BMI > 30 or ~ 30 lbs overweight for 5 4 person

27 Prevalence* of Self-Reported Obesity Among U.S. Adults by State and Territory, BRFSS, 2011 WA CA OR NV ID UT MT WY CO ND SD NE KS MN IA MO WI IL VT NY MI PA IN OH WV VA KY ME NH MA RI CT NJ DE MD DC AZ NM OK AR TN NC SC AK TX LA MS AL GA FL HI GUAM PR 15% <20% 20% <25% 25% <30% 30% <35% 35%

28 Prevalence* of Self-Reported Obesity Among U.S. Adults by State and Territory, BRFSS, 2013 WA CA OR NV ID UT MT WY CO ND SD NE KS MN IA MO WI IL VT NY MI PA IN OH WV VA KY ME NH MA RI CT NJ DE MD DC AZ NM OK AR TN NC SC AK TX LA MS AL GA FL HI GUAM PR 15% <20% 20% <25% 25% <30% 30% <35% 35%

29 Causes of Obesity Obesity results from an energy imbalance Intake of calories > Expenditure Body weight is the result of genes, metabolism, behavior, environment, culture, and socioeconomic status People don t just decide to become overweight

30 Obesity: A Multifactorial Disease Genetic Environmental Behavioral

31 Causes of Obesity The way we eat has changed dramatically Processed foods Eat out more Sugar filled drinks Cheap food is often bad food Convenience ( Fast food ) Limited access to healthy options in poor areas

32 Causes of Obesity: Dietary Energy Supply "EarthTrends: Nutrition: Calorie supply per capita". World Resources Institute. 2009

33 Causes of Obesity Our activities have changed Less outdoors play More TV, videogames Drive everywhere Sedentary work environment Unsafe to walk/play in inner cities Convenience or Inconvenience

34 Causes of Obesity Poorly understood environmental variables Nutrition during fetal development Stress Sleep deprivation Viral infections Gut microbial composition

35 Causes of Obesity Obesity is a Metabolic Disease

36 Metabolic Pathways of Weight Control

37 Metabolic Pathways of Weight Control The Fat-o-Stat Built-in mechanisms to maintain stable weight Humans biased in favor of storing fat Genetic susceptibility - the FTO gene 40,000 people s genomes studied Carriers of FTO gene (Fxn unknown) 3 kg heavier Therapeutic possibilities for weight reduction?

38 Metabolic Pathways of Weight Control THE BRAIN The Hypothalamus - Grand Central Station Old animal studies: Destroy one area» Obesity Destroy another» Starvation Identified as Satiety or Feeding centers

39 Metabolic Pathways of Weight Control Brain Signals Many Substances influence appetite: Glucose Insulin Cholecystokinin Leptin 1994 Friedman, Rockefeller Univ. Inherited gene mutation in mice Active in fat cells - made non-functional protein Inject functional Leptin lowered weight by decreasing appetite and increasing energy expenditure

40 Metabolic Pathways of Weight Control LEPTIN Rare cause of early obesity in humans First Fat Cell hormone that reflects energy storage Triglyceride storage - Leptin production

41 Metabolic Pathways of Weight Control Leptin Resistance Most people with obesity have no known genetic mutations that could explain their condition Leptin levels are actually higher than lean individuals Leptin Resistance proteins, normally modulate Leptin signals in brain In Obesity, these proteins overcompensate for high Leptin levels

42 Metabolic Pathways of Weight Control Visceral Responses Full stomach Nerve response via stretch receptors Liver Energy status transmitted via Vagus nerve Gut Hormones Insulin - Suppress appetite CCK - short-term satiety Peptide PYY - small intestine, short-term satiety

43 Metabolic Pathways of Weight Control Grehlin Only gut peptide known to appetite Released from stomach before feeding Depresses metabolism Increases dramatically during weight loss provoking increased hunger, inability to keep weight off Decreases after Bariatric Surgery

44 Metabolic Pathways of Weight Control Adiponectin Produced and excreted exclusively by fat cells Improves glucose and lipid processing Fasting raises levels in CSF, triggers release of appetite stimulating peptide NPY Decreased circulating levels in Obesity (Leads to insulin resistance) Starvation Signal

45 Obesity Comorbidities Pulmonary disease abnormal PFTs obstructive sleep apnea hypoventilation syndrome Non-alcoholic fatty liver disease steatosis steatohepatitis cirrhosis Gall bladder disease Gynecologic abnormalities abnormal menses infertility polycystic ovarian syndrome stress incontinence Osteoarthritis Skin Gout Depression Stroke GERD Cardio/Metabolic Syndrome diabetes (80% type 2) dyslipidemia hypertension metabolic syndrome Severe pancreatitis Cancer (42% Breast/Colon) breast, uterus, cervix colon, esophagus, pancreas kidney, prostate Phlebitis venous stasis Premature Death

46 Obesity Comorbidities Prevalence of Significant Morbidities per Weight JAMA 2003

47 Comorbidities: The Metabolic Syndrome Estimated to impact 47 million U.S. adults Presence of 3 or more of the following Central obesity (Waist circumference >40 men, >35 women) Elevated fasting triglycerides (>150 mg/dl) Low blood HDL cholesterol (<40 men, <50 women) High blood pressure (> 130 systolic / 85 diastolic) Elevated fasting glucose (> 100 mg/dl or drug Rx)

48 Comorbidities: The Metabolic Syndrome

49 Comorbidities: The Metabolic Syndrome Pathophysiology of Metabolic Syndrome Central Obesity Complex interaction between genetic, metabolic, and environmental factors Dyslipidemia Insulin Resistance Hyper-Insulinemia Type 2 Diabetes Heart Disease Recent studies suggest metabolic syndrome may be an inflammatory state. Hypertension

50 Comorbidities: Obstructive Sleep Apnea

51 Comorbidities: Obstructive Sleep Apnea Results: 0-10 Normal Mild to Moderate Sleep Apnea 16+ Severe Sleep Apnea >11 warrants further testing

52 Comorbidities: Obstructive Sleep Apnea Results in excess daytime sleepiness Decreased alertness Increased risk of driving accidents Increased risk of diabetes and heart disease Depression Fatty liver disease 4.8 times higher risk of cancer mortality

53 Comorbidities: Obstructive Sleep Apnea Before surgery One year later Morning Headaches Always 18% 0 Sometimes 32% 16% Never 50% 84% Waking Unrefreshed Always 56% 4% Sometimes 24% 31% Never 20% 65% Habitual snoring 82% 14% Sleep apnea 33% 2% Nocturnal choking 24% 0 Atkinson RL., et al. JAMA, 2000, 283(24):

54 Comorbidities: Obstructive Sleep Apnea 100 Patients with symptoms of OSA Prospectively evaluation with Polysomnography 13 No OSA 29 Mild 58 Severe Severity did not correlate with BMI Pre and Post-op Epworth Sleepiness Scale, Respiratory Disturbance Index Rasheid et.al. Obesity Surgery 2003;

55 Comorbidities: Obstructive Sleep Apnea n Preop Postop Up to 21 months BMI ESS RDI SpO Rasheid et.al. Obesity Surgery 2003;

56 Comorbidities: Cancer Esophagus Pancreas Colon and rectum Breast (After menopause) Endometrium Kidney Thyroid Gallbladder

57 Comorbidities: Cancer 34,000 new cancer cases in men (4%) 50,500 new cancer cases in women (7%) As much as 40% of endometrial and esophageal adenocarcinomas An increase in BMI of 5 kg/m 2 increases cancer mortality risk 10%

58 Comorbidities: Cancer Mechanisms of cancer in obesity Fat tissue produces excess amounts of estrogen Increased levels of insulin and IGF-1 Fat cells produce Adipokines Leptin: Promotes cell growth Direct and indirect effects on tumor growth regulators mtor, AMP-activated protein kinase Increased levels of inflammatory mediators Chronic inflammation Altered immune response

59 Comorbidities: Cancer Swedish Obesity Study (SOS) 13 year follow-up after bariatric surgery showed significant decrease in incidence of first cancer in women (p=.0009) Improved natural killer cell function

60 The Obesity Epidemic - Solutions INVOLVES MANY LEVELS Change diet Drink water Increase physical activity Limit TV, Video games School Health Advisory Council Improve food offered to children

61 The Obesity Epidemic - Solutions Employer sponsored programs Work site health programs Healthy food options Health insurance wellness benefits Improve access to healthy Government sponsored Farmers markets Incentivize stores to open in less desirable areas

62 Obesity Treatment Options Diet Only 3% to 5% of patients lose an appreciable amount of weight. Few keep it off. Exercise Behavioral Pharmaceuticals Surgery

63 Obesity Treatment Pyramid SURGERY BMI 35+ with comorbidities BMI 40+ PHARMACOTHERAPY BMI 27+ with comorbidities BMI 30+ LIFESTYLE MODIFICATIONS BMI 25+

64 Obesity Treatment Options

65 Obesity Treatment Options: Behavior 5 Weight change (kg) Very-low-calorie diet Modified diet plus behaviour therapy Very-low-calorie diet plus behaviour therapy -20 intervention Source: Bray GA, Bouchard C and Jones WPT eds. Handbook of Obesity. New York, NY: Marcel Dekker; 1998:31-40 from data in Wadden TA et. al. Int J Obes 1989;13 Suppl 2:39-46

66 High Attrition Rate of Commercial Diet % participating Weeks after commencement of program

67 Obesity Treatment Options Surgery Severe obesity can be treated successfully. Bariatric surgery is the standard of care. Only surgery has proven effective over the long term for most patients with clinically severe obesity - National Institutes of Health Consensus Development Conference Statement

68 Types of Surgery: A Long History Restrictive Vertical Banded Gastroplasty (VGB) Gastric Banding (Lap Band) Vertical Sleeve Gastrectomy Malabsorptive Jejunoileal Bypass (JIB) Biliopancreatic Diversion (BPD) Duodenal Switch Long Limb Gastric Bypass Intermediate Roux-en-Y Gastric Bypass (LRYGB)

69 Most Common Bariatric Procedures Roux-en-Y Gastric Bypass Bypass a portion of the small intestine and create a 15-30cc stomach pouch Adjustable Gastric Banding Place implantable device around upper most part of stomach Sleeve Gastrectomy Resect approximately 80% of the stomach

70 Metabolic Effect of Bariatric Surgery

71 Resolution of Comorbidities after Bariatric Surgery

72 Improved Survival with Surgery 5 year Follow up 6.17% (n=5746) mortality rate among NON-SURGICAL group (control Group) 0.68% (n=1035) mortality rate among SURGICAL GROUP Average of Control (%) Average of Surgical (%) 89% reduction in relative risk of mortality in 5 year period 1 0 Christou et al. Ann Surg. 2004; 240:

73 Bariatric Surgery - Low Incidence of Mortality *When performed at a Bariatric Surgery Center of Excellence

74 Bariatric Surgery Risks/Complications There are different complication associated with the different surgeries Gastric Bypass: Leak or Blockage requiring re-operation Gastric Banding: Band slip, band erosion or port flip Gastric Sleeve: Leak, stricture, dilatation

75 Bariatric Surgery Intra-op Complications Equipment failure stapler misfire, suture disruption, bleeding Anatomical variances Weak anastamosis Laparoscopy related complications pneumo-thorax, low venous return, inadequate workspace

76 Bariatric Surgery Post-op Complications Anastamotic leak (0.1-10%) Tachycardia Low grade fever Low urine output Signs of sepsis EXAM AND PAIN ARE NOT RELIABLE

77 Bariatric Surgery Post-op Complications Atelectasis (10%) DVT ( %) Gastric distension (distal divided stomach) Hypoxia (Obesity Hypoventilation Syndrome (OHS)) Sleep Apnea Pulmonary Embolism

78 Bariatric Surgery Late Complications Malnutrition/Malabsorption Anemia B12, Iron def. Hypocalcemia Bone Loss, secondary Hyper PTH Marginal Ulcers (3-9%) Stomal Stenosis (4-20%) Hernia (3-30%)

79 Roux-En-Y Gastric Bypass: Results Gastric Bypass provides durable weight control - Weights fell from preoperative mean of lb to * lb. At 1 yr. * lb at 5 yr. * lb at 10 yr. N=608 patients * lb at 14 yr Poires WJ, Swanson MS MacDonald KG et al. Who would have thought it? An operation proves to be the most effective therapy for adult onset diabetes mellitus. Ann Surg 1995; 222:339-52

80 Husband and Wife 1 Year Post-op

81 The Obesity epidemic - Conclusions Obesity is rapidly increasing worldwide due to a complex interaction of social, environmental, genetic and metabolic factors There are numerous health risks associated with obesity which lead to a significant reduction in life expectancy and have a large economic impact on society

82 The Obesity epidemic - Conclusions Comorbid conditions are often under diagnosed and inadequately treated Bariatric surgery is an option when all other attempts at weight reduction have failed, and provides excellent resolution of most obesity related conditions

83 Now It s Your Turn Audience Question and Answer Session