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CLINICAL DILEMMAS IN OBESITY MANAGEMENT. Robert B. Baron MD MS Professor and Associate Dean UCSF School of Medicine Declaration of full disclosure: No conflict of interest. Case 1. 50 year old woman, in good health, no history of cigarettes, in for check up. BMI 29.
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CLINICAL DILEMMAS IN OBESITY MANAGEMENT • Robert B. Baron MD MS • Professor and Associate Dean • UCSF School of Medicine • Declaration of full disclosure: No conflict of interest
Case 1 • 50 year old woman, in good health, no history of cigarettes, in for check up. BMI 29. • Should you tell her she is overweight? • What further assessment and treatment should you begin?
CLASSIFICATION OF OVERWEIGHT AND OBESITY BY BMI • Obesity Class BMI (kg/m2) Underweight <18.5 Normal 18.5 – 24.9 • Overweight 25.0 – 29.9 • Obesity I 30.0 – 34.9 • II 35.0 – 39.9 • Extreme Obesity III >40
BMI AND MORTALITY: Overall • Combined NHANES I, II, and III data set • BMI 25-59 y 60-69 y ≥70 y • <18.5 1.38 2.30 1.69 • 18.5-<25 1.00 1.00 1.00 • 25 to <30 0.83 0.95 0.91 • 30 to <35 1.20 1.13 1.03 • ≥35 1.83 1.63 1.17 Flegal, JAMA, 2005
An Office-Based Approach • Make the diagnosis (and communicate it) • Assess readiness for change • Prescribe diet and exercise • Consider medications and surgery
HEALTH PROFESSIONAL ADVICE AND WEIGHT LOSS • 12,835 adults, BMI over 30 kg/m2, check-up in last year • Random-digit, population-based sample, 50 states • 42% told by health professional to lose weight • Those told to lose weight more likely to report trying to lose weight: OR 2.79 (95% CI 2.53-3.08)
INTENTIONAL WEIGHT LOSS AND DEATH • Prospective CDC cohort study, 6391 adults, followed for 9 years • Those reporting intentional weight loss had 24% reduction in mortality • Those reporting unintentional weight loss had 31% higher mortality • Those reporting attempted but unsuccessful weight loss also had 20% reduction in mortality Gregg, Ann Int Med 2003
METABOLIC SYNDROME • Fulfill 3 or more criteria: • Waist: men > 102 cm ( > 40 in); women > 88 cm ( > 35 in) • HDL: men < 40; women < 50 • Triglycerides: ≥150 mg/dl • BP: ≥130/85 (or use of medications) • Fasting glucose: ≥110 mg/dl • ICD-9: 277.7 NCEP, JAMA 2001
GOALS OF MANAGEMENT • Be as fit as possible at current weight • Prevent further weight gain • If successful at 1 and 2, begin weight loss
Case 2 • 50 year old woman, in good health, in for check up. BMI 32 with metabolic syndrome. • She says, “ I have to lose weight, and I am planning on doing that. I am about to try the South Beach diet.”
DIET THERAPY • 48 RCT’S • Average weight loss 8% over 3-12 months
VLCD’s vs LCD’s: Meta-analysis of 29 U.S. Studies • Weight loss studies with > two year f/u • 13 VLCDs, 14 LCDs • Mostly observational studies (few RCT’s) • Weight loss (as % of initial weight): • 1y 2y 3y 4y 5y • LCDs 7.2 4.2 3.5 2.8 2.0 • VLCDs 16.1 9.7 7.8 7.0 6.2 Anderson, Am J Clin Nutr, 2001
COMPARISON OF ATKINS, ORNISH, WEIGHT WATCHERS, AND ZONE 160 patients, randomly assigned • Intention to treat at 1 year • AtkinsOrnishWWZone • Wt Loss (kg) 2.1 3.3 3.0 3.2 • Completers (%) 53 50 65 65 • Completers at 1 year • AtkinsOrnishWWZone • Wt Loss (kg) 3.9 6.6 4.6 4.9 Dansinger, JAMA 2005
COMPARISON OF ATKINS, ORNISH, WEIGHT WATCHERS, AND ZONE • Each group: 25% lost 5%, 10% lost 10% of initial weight • Each diet reduced LDL/HDL by 10% • No significant effects on BP or glucose • Weight loss associated with adherence, but not diet type • CRP and insulin reductions associated with weight loss, but not diet Dansinger, JAMA, 2005
DIET APPROACHES • Diets low cal (low fat, low carbohydrate), meal replacement • Commercial programs Weight Watchers™, Jenny Craig™, TOPS™, Overeaters Anonymous™, Nutrisystem.com,™ Shapedown,™ The Solution™ • Internet programs (by RDs) Fitday.com, Dietwatch.com, Cyberdiet.com, eDiets.com, Shapeup.org
FITNESS AND MORTALITYAerobics Center Longitudinal Study 25,714 men, 44 years old, 14 year observational study • CV death (RR) • normal overweight obese • Fit 1.0 1.5 1.6 • Not fit 3.1 4.5 5.0 • Total death (RR) • normal overweight obese • Fit 1.0 1.1 1.1 • Not fit 2.2 2.5 3.1 Wei, JAMA 1999
FITNESS AND OBESITYNurses Health Study 116,564 women, 24 year observational study • Total death (RR) • normal overweight • Active 1.00 1.91 • Not active 1.55 2.42 Hu FB, NEJM 2004
SUCCESSFUL WEIGHT LOSS MAINTENANCE • 3000 subjects in National Weight Control Registry: 30-lb weight loss for 1-year • Average weight loss 30kg (10 BMI units less), average weight maintenance 5.5 years • 45 years old, 80% women, 97% Caucasian • 46% overweight as child, 46% one parent obese, 27% both parents Wing and Hill, Ann Rev Nutr, 2001
SUCCESSFUL WEIGHT LOSS MAINTENANCE • High levels of physical activity • Women 2545 kcal/week, men 3293 kcal/week • (1-hour moderate intensity per day • Only 9% report no physical activity • Diet low in fat, high in carbohydrate • 1381 kcal day, 24% fat, 19% protein, 56% CHO • 4.87 meals or snacks/day • Fast food 0.74/week • Regular self-monitoring of weight • 44% weigh once per day; 31% once per week Wing and Hill, Ann Rev Nutr, 2001
Case 3 • 46 year old woman, in good health, in for check up. BMI 42 with diabetes. • In 1996 she lost 20 pounds on phen-fen. She wants a new weight loss drug and a referral for weight loss surgery.
“LONG TERM” PHARMACOTHERAPY OF OBESITY • Review of all RCT’s more than 36 weeks published since 1960 • Weight loss in excess of placebo: • % of initial kg’s • Phen-fen 11.0% 9.6 kg • Phentermine 8.1% 7.9 kg • Sibutramine 5.0% 4.3 kg • Orlistat 3.4% 3.4 kg • Dexfenfluramine 3.0% 2.5 Kg • Fluoxetine -0.4% -0.4 kg • Diethyproprion -1.5% -1.5 kg Glazer, Arch Int Med 2001
SIBUTRAMINE ALONE AND WITH LIFESTYLE MODIFICATION Wadden, T. A. et al. N Engl J Med 2005;353:2111-2120
OFF-LABEL USE • Sertraline – SSRI • More selective 5-HT uptake inhibitor • In Phase III trials now • Buproprion – NA re-uptake inhibitor • RCT of 327 obese pts, 24 weeks; • Wt. loss: 2% placebo vs. 5% in 300/400 mg • Topiramate – CA inhibitor • RCT in 385 obese pts; dose-ranging; 24 wks • Wt loss: -2.6% placebo vs. -5 to -6% w/drug
OTHER DRUGS OFF-LABEL • Amantadine • Other SSRIs (fuvoxamine, venlafaxine, citalopram, others) • H2 blockers (cimetidine) • Metformin • Wt loss: -2 kg with drug vs. -0 kg with placebo vs. -4 kg with lifestyle in DPP • Exenatide (Byetta) • - Wt loss: -4-5 kg in open label study at 80+ weeks • Zonisamide – antiepileptic • Wt loss: -5.9 kg with drug vs. 0.9 kg with placebo
RIMONABANT (Acomplia™) • 1,507 severely obese people, Europe, 2-years (2005) • rimonabant 7.3 kg loss • placebo 2.5 kg loss • 3,040 obese people, US, 2-years (2004) • rimonabant 7.6 kg loss • placebo 2.3 kg loss
Placebo 5 mg of Rimonabant 20 mg of Rimonabant 0 12 24 36 52 Year 1 Body Weight Change From Baseline, kg Weeks
Placebo/Placebo 20 mg rimonabant/Placebo 20 mg rimonabant/20 mg Year 2 Body Weight Change From Baseline, kg 52 60 68 76 84 92 104 Weeks
RIMONABANT (Acomplia™)Side Effects Nausea: 13.7% with drug vs. 5.5% on placebo Dizziness: double with drug Diarrhea: double with drug Depression: 2.8% vs. 1.6% Drop outs: 19% with drug vs. 13% with placebo
PRINCIPLES OF DRUG THERAPY • NIH: BMI > 30 kg/m2 or 27 kg/m2 with co-morbidity (but in practice almost never) • Motivated to begin structured exercise and low calorie diet • Begin medications at completion of one month successful diet and exercise • Continue medications only if additional weight loss achieved in first month with meds
Projection based on preliminary data from 12 states for 2003 1998 1999 2000 2001 2002 2003 National Trends in Annual Numbers of Bariatric Procedures, 1998-2003 Data based on nationwide inpatient sample No. of Procedures Year Error bars indicate 95% confidence intervals
Who’s Getting Surgery? • Approved by most payers; cost effective • Recent review indicates more surgeries done in: • women • those with private insurance • those living in wealthier zip codes Santry HP et al JAMA 2005;294:1909
Types of Surgery • Restrictive • Horizontal Gastroplasties • Vertical Banded Gastroplasty (VGB) • Silastic Ring Vertical Gastroplasty (SRVG) • Adjustable Gastric Banding • Malabsorptive • Jejunoileal Bypass (JIB) • Biliopancreatic Diversion (BPD) • Duodenal Switch • Long Limb Gastric Bypass • Restrictive with Malabsorptive Component • Roux-en-Y Gastric Bypass (RYGPB)
Restrictive Procedures Roux-en-Y GB Adjustable Gastric Banding VBG
BARIATRIC SURGERY META-ANALYSIS • Review of bariatric surgery (136 studies), 1990-2003, 22,092 patients • weight loss (kgs)BMI decrease% excess weight loss • Total -39.71 -14.20 -61.23 • Gastric Banding -28.64 -10.43 -47.45 • Gastric Bypass -43.48 -16.70 -61.56 • Gastroplasty -39.82 -14.20 -68.17 • Biliopancreatic diversion • or duodenal switch -46.39 -17.99 -70.12 Buchwald, JAMA, 2004
BARIATRIC SURGERY META-ANALYSIS • Review of bariatric surgery (136 studies), 22,092 patients • Operative Mortality • Gastric Banding 0.1% • Gastric Bypass 0.5% • Gastroplasty 0.1% • Biliopancreatic diversion • or duodenal switch 1.1% Buchwald, JAMA, 2004
Mortality Rate After Bariatric Surgery Flum, D. R. et al. JAMA 2005;294:1903-1908. .
Survival After Bariatric Surgery by Age Group Flum, D. R. et al. JAMA 2005;294:1903-1908.
LACK OF METABOLIC EFFECTS OF LIPOSUCTION • 15 women, before and after liposuction (8 with normal glucose tolerance, 7 with diabetes) • Weight loss: 9.1 kg (NLs) and 10.5kg (DM) • No change in insulin sensitivity of muscle, liver, or adipose tissue • No change in C-reactive protein, IL-6, TNF alpha or adiponectin • No change BP, glucose, insulin, lipids Klein, NEJM 2004