besity Epidemiology of obesity Objectives Body Mass Index = Weight (kg) Height (m 2 ) U.S. Adults with BMI 30 BRFSS, 1986

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1 Objectives besity Dr A Qureshi MB ChB (Edin), MD (Lon), CCST (Lon), FRCP (Lon) Consultant in Endocrinology, Diabetes and General Internal Medicine w w w. e n d o c r i n o l o g y s p e c i a l i s t. c o m Epidemiology of obesity The aetiology of the epidemic Obesity and co-morbidities The financial cost of obesity Treatment of obesity Private practice Clementine Churchill Garden Hospital Wellington Hospital NHS practice Northwick Park Hospital Developing obesity services Body Mass Index BMI CLASSIFICATION = Weight (kg) Height (m 2 ) BMI Healthy weight 2-25 Overweight 25-3 Obese 3-35 Severely obese 35-4 Morbidly obese >4 Epidemiology of obesity BRFSS, 1985 BRFSS, 1986 No Data <1% 1% 14% No Data <1% 1% 14%

2 BRFSS, 1987 BRFSS, 1988 No Data <1% 1% 14% No Data <1% 1% 14% BRFSS, 1989 BRFSS, 199 No Data <1% 1% 14% No Data <1% 1% 14% BRFSS, 1991 BRFSS, 1992 No Data <1% 1% 14% 15% 19% No Data <1% 1% 14% 15% 19%

3 BRFSS, 1993 BRFSS, 1994 No Data <1% 1% 14% 15% 19% No Data <1% 1% 14% 15% 19% BRFSS, 1995 BRFSS, 1996 No Data <1% 1% 14% 15% 19% No Data <1% 1% 14% 15% 19% BRFSS, 1997 BRFSS, 1998 No Data <1% 1% 14% 15% 19% 2 No Data <1% 1% 14% 15% 19% 2

4 BRFSS, 1999 BRFSS, 2 No Data <1% 1% 14% 15% 19% 2 No Data <1% 1% 14% 15% 19% 2 BRFSS, 21 BRFSS, 22 No Data <1% 1% 14% 15% 19% 2% 24% 25% No Data <1% 1% 14% 15% 19% 2% 24% 25% BRFSS, 23 BRFSS, 24 No Data <1% 1% 14% 15% 19% 2% 24% 25% No Data <1% 1% 14% 15% 19% 2% 24% 25%

5 Prevalence of obesity in UK Prevalence of obesity Prevalence of obesity (BMI>3) Women Men Prevalence (%) >4 BMI (kg/m2) CDC, National Center for Health Statistics, National Health and Nutrition Examination Survey. Health, United States, 22. Flegal et. al. JAMA. 22;288: NIH, National Heart, Lung, and Blood Institute, Clinical Guidelines on the Identification, Evaluation and Treatment of Overweight and Obesity in Adults, BMI in patients in NWP diabetes clinic BMI in children Percentage of all patients >4 BMI (kg/m2) n=282 Obesity in children in the UK Obesity in children in UK Prevalence of obesity Boys Girls Health Survey for England 22

6 Summary of epidemiology Classification of obesity by BMI Rising prevalence of obesity Female>male In children The aetiology of the epidemic Its my metabolic rate! London has high rates of childhood obesity National Food Survey Calorie content of food constituents Since 195 s average energy intake increased per household Constituent Calories/gms Peaked in 197 Declining intake since then However, the following were not included Alcoholic/soft beverages Fat 9 Alcohol 7 Protein 4 Carbohydrate 4 Restaurant/take-away foods Calories in beverages Sedentary life style Beverage Kcal Beer, Bitter, 1 Pint 18 Coke, Coca Cola*1 Can/33ml 139 Orange Juice, 2ml 92 White Wine, 12ml 87 Coffee, Semi-Skimmed Milk, 2ml 14 Tea, With Semi-Skimmed Milk, 2ml 14

7 Physical activity CHILDREN High school PE (>2 minutes per day) % % Walking and bicycling: 4% decline between 1977 and 1995 Increase in time: watching television playing video games computer Calories expended in activity Activity Calories burnt/hr Lying down or sleeping 9 Driving 15 Walking (2 mph) 198 Football (touch, vigorous) 498 Aerobic Dancing 546 Interesting facts 1 digestive biscuit = ½ hour walk Resting metabolic rate accounts for 65% of your energy used ALL movements (including exercise) account for the remainder Resting metabolic rate is dependent on Sex Age Height WEIGHT Summary of the aetiology of the obesity epidemic Obesity epidemic is due to Increased calorie intake Sedentary life-style Genetics does not explain the epidemiological changes Obese patients do not have a low metabolic rate Obesity and co-morbidities Obesity and co- morbidities Obstructive Sleep Apnoea Obesity Hypoventilation Syndrome Asthma Pulmonary hypertension Diabetes mellitus Dyslipidaemia Hypertension Cardiomyopathy CCF Ischemia heart disease Cerebrovascular accidents Deep vein thrombosis and pulmonary embolism Gallbladder disease Arthritis Reproductive complications Depression Social Discrimination Cancers Endometrial Breast Colon Kidney

8 Co- morbidities in obesity Relative risk of type II diabetes with rising BMI Co-morbidity Relative risk women Relative risk-men T2DM Hypertension MI Ca colon Angina Gall bladder disease Ovarian ca Osteoarthritis CVA Relative risk >35 BMI (kg/m2) Colditz Am J Epi , Relative risk of hypertension with rising BMI All cause mortality and obesity (women) Relative risk Relative risk >35 BMI (kg/m2) >36 BMI (kg/m2) Adapted from National Health and Nutrition Examination Survey. Health, United States, 22. Manson JE, Willet WC, Stampfer MJ (1995). Bodyweight and mortality among women. NEJM Abuse Psychological aspects of obesity 6yr old children perceive obese children as lazy, dirty, stupid, ugly, liars and cheats (Wadden TA et al., 1985) Weight discrimination (Gortmaker SL et al., 1993) Eating disorders Binge eating Night eating disorder Physical/verbal/sexual abuse in childhood Summary of co-morbidities in obesity Numerous co-morbidities Physical Mental Relative risk rises with increasing BMI

9 Financial burden of obesity The financial cost of obesity Direct NHS costs 5 million in 1998 Indirect costs 1,7 to 1,9 million in 1998 (3.5-4% NHS expenditure) 3.6 billion by 21 Costs now rival those for smoking NICE guidelines, 21 Centers for Disease Control and Prevention. Tobacco information and prevention source. Finkelstein EA, Fiebelkorn IC, Wang G. State-level estimates of annual medical expenditures attributable to obesity. Obesity Research. January 24;18-24 The cost of obesity Breakdown of treatment costs of obesity Day cases Outpatients Prescriptions Admissions GP consultation Cost ( million) Treating obesity Treating the consequences of obesity Hypertension CHD Diabetes Osteoarthritis Cancers Stroke Cost ( million) National Audit estimates National Audit estimates Which patient is most expensive? Prevalence of obesity Prevalence (%) >4 BMI (kg/m2) CDC, National Center for Health Statistics, National Health and Nutrition Examination Survey. Health, United States, 22. Flegal et. al. JAMA. 22;288: NIH, National Heart, Lung, and Blood Institute, Clinical Guidelines on the Identification, Evaluation and Treatment of Overweight and Obesity in Adults, 1998.

10 Relative risk of type II diabetes with rising BMI Prevalence x relative risk ( ) Relative risk >35 BMI (kg/m2) Prevalence x relative risk of type II diabetes >25 >3 >4 BMI (kg/m2) Colditz Am J Epi , CDC, National Center for Health Statistics, National Health and Nutrition Examination Survey. Health, United States, 22. Flegal et. al. JAMA. 22;288: NIH, National Heart, Lung, and Blood Institute, Clinical Guidelines on the Identification, Evaluation and Treatment of Overweight and Obesity in Adults, 1998 AND Colditz Am J Epi , Costs ($) 2, 15, 1, 5, Annual per-person medical costs BMI 3-35 BMI >35 Norm al BMI 25-3 Sm oker Cauasian females Age (yrs) Summary of costs of obesity Burden equates to that of smoking 4 times as much is spent on co-morbidities than on treating obesity 3 major co-morbidities (financially) Hypertension Coronary heart disease Type 2 diabetes 2-22 Medical Expenditure Panel Survey (MEPS) Figures not adjusted for survival Stakeholders Managing obesity Food standards agencies Employers Individual Department of health Department of education Consumer representatives Voluntary bodies Group Community Society Food industry Local education authorities Commercial slimming organisations Media Sport England Strategic health authorities Health professionals

11 Benefits of a 1% weight loss in obesity Mortality 2-25% fall in total mortality 3-4% fall in diabetesrelated deaths 4-5% fall in obesity-related cancer deaths Blood pressure Fall of 1 mm Hg systolic Fall of 2 mm Hg diastolic Angina 91% reduction in symptoms 33% increase in exercise tolerance Lipids 1% fall in total cholesterol 15% fall in LDL cholesterol 3% fall in triglycerides 8% increase in HDL cholesterol Diabetes >5% reduction in risk of developing diabetes 3-5% fall in fasting blood glucose 15% fall in HbA 1c Medical treatment of obesity Mechanisms of Action of Weight-Loss Drugs Three broad categories 1. Decrease food intake 2. Decrease nutrient absorption NICE guidelines on anti- obesity drugs 3. Increase energy expenditure NICE guidelines on orlistat, 21 Adult tried life-style measures BMI 28 kg/m2 and co-morbidity or BMI 3 kg/m2 Lost >2.5 kg prior to prescription May require vitamin supplements Only continue for >3 months if at least 5% weight loss Only continue for >6 months if at least a 1% weight loss Treatment limit 24 months Estimated finances Direct = 6M and indirect = 3M NICE guidelines on sibutramine, 21 Adult tried life-style measures BMI 27 kg/m2 and co-morbidity or BMI 3 kg/m2 Only continue > 4 weeks if weight loss of at least 2 kg Only continue > 3 months if weight loss of at least 5% Treatment limit 12 months Monitor BP and pulse regularly rule of 1 Estimated finances 8.4 million in first yr 19.2 million after 3 years

12 Sibutramine Orlistat Percentage weight loss n= Week Placebo Sibutramine 5mg Sibutramine 3mg Percentage weight loss Hypocaloric diet Eucaloric diet Week Placebo Orlistat Orlistat Bray GA et al, Obes Res 1999; 7:189 Sjostrom L et al, Lancet 1998; 352:167 Typical weight fluctuation Tanaka M, Itoh K, Abe S, Imai K, Masuda T, Koga R, Itoh H, Konomi Y, Kinukawa N, Sakata T. Irregular patterns in the daily weight chart at night predict body weight regain. Exp Biol Med (Maywood). 24 Oct;229(9):94-5.

13 Why does weight loss plateau? Surgical treatment of obesity Calorie intake Time (days) Weight Resting metabolic rate Surgery Gastric balloon Restrictive Gastric balloon Vertical banded gastroplasty Adjustable gastric banding Malabsorptive Gastric bypass Jejunoileal bypass All require intense pre-treatment workup Vertical banded gastroplasty Adjustable gastric banding Banding Vs gastroplasty long-term weight loss (5yrs)

14 Roux-en-Y gastric bypass Gastric bypass Vs gastroplasty Jejunoileal bypass Greater weight loss operative mortality revision rates J-I bypass Vs gastric bypass weight loss complications Weight Loss 66% at 1 to 2yrs 6% at 5 years 5% at 1 years Effectiveness of surgery Jejunoileal bypass versus medical More effective at 12 months 43kg Vs 6kg, p<.1 Vertical banded gastroplasty Vs VLCD As effective at 12 months; 23kg Vs 18kg More effective at 24 months; 32kg Vs 9kg, p=<.5 Weight loss can be maintained beyond 8yrs Cost of surgery in obesity Surgery and pre-operative assessment 1 year 53 Costs of surgical therapy are half those for VLCD (when maintaining weight loss for 2-6yrs) Surgery is more cost-effective than medical treatment 11, over 1yrs Equivalent to 1yrs of orlistat Surgical costs may be further reduced by laproscopic techniques Complications of surgery Operative mortality Dumping syndrome Malabsorption Stomach rupture NICE guidelines Morbidly obese (BMI>4kg/m2) Adults receiving intensive input in obesity clinic No clinical or psychological contra-indications Accept long-term follow up Only after multi-disciplinary team assessment Do not distinguish between types of surgery

15 Evidence-based algorithm for treatment of obesity Summary of management of obesity BMI 3 or 25 with co-morbidities Medical profession is only part of global strategy Lifestyle advice Use of life-style measures in all Progress no yes Weight maintenance Medication 1% loss and poorly sustained Short trials BMI 3 or 27 with co-morbidities BMI 4 or 35 with co-morbidities Surgery Pharmacological therapy Lifestyle Surgery if other attempts have failed Greater sustained weight loss than other treatments Require multi-disciplinary team Example SHA proposals Developing obesity services Training healthcare workers to give lifestyle advice Encourage walking / cycling Working with local authorities Promoting active recreation Healthy school environment Specialist obesity clinics Primary care and obesity Survey of 12 GPs (n=428) and 12 practice nurses (n=627) 66% of GPs consider primary care as an opportunity to treat obesity 64% of GPs believed the treatment available to them were not effective 75% of GPs believe they have a role in referring patients for management of obesity 75% of nurses wanted guidelines Only 25% were able to refer to specialist opinion Managing obesity at NWP Currently 1 extra-contractual referral per week to obesity clinics No specialist dietician obesity psychologist exercise specialist surgical service no long-term support specialist obesity clinic adequate equipment

16 Role of an obesity clinic Stakeholders Referral avenue for primary care Very low calorie diets Food standards agencies Department of health Medical and surgical treatment Specialised dietician-led follow up Psychologist Exercise specialist Clinical trials Treatment guidelines Employers Consumer representatives Voluntary bodies Individual Group Community Society Department of education Food industry Local education authorities Liaises with SHA/primary care/local health authority Commercial slimming organisations Media Sport England Strategic health authorities Health professionals