Medical Management of Obesity

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Medical Management of Obesity

• Robert Schmidli
• FRACP, PhD
• Consultant Physician,
• Diabetes and Endocrinology

2
Case history

• Paul 38 years, public servant
• Normal weight as child, football during teens.
  Stopped when 19
• Weighed 70kg at 18y
• Progressive weight gain. Now 130kg
• Frequent travel and work lunches
• Works late in evenings
• No special attention to diet
• No time for exercise

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Examination

• Weight 130kg, height 1.8, BMI 40
• Blood pressure 150/80
• Healthy, no abnormality
• Cholesterol 4.0
• Fasting blood glucose 6.2

What are the main issues? What should Paul do?
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Definition

• Body mass index weight ? height2
• Ideal 20 25
• Overweight 25 30
• Obese 30

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How common is it?

• Australia second to USA in world
• AusDiab study
• Overweight 60 both sexes
• 2½ - fold increase in obesity compared to 1980
• Associations
• Television viewing time
• Lower physical activity time

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Benefits of weight loss

• 9.1kg weight loss ? 35 ? death rate
• Surgery ? 69 cure of diabetes
• Death rates lower in individuals trying to lose
  weight
• Blood pressure ? 0.3 1.0 mmHg for each kg
  weight lost

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Weight loss targets

• Diabetes Prevention Trial 3234 people
• High risk for diabetes
• 7 weight loss target
• Exercise 150 min/week
• 16-lesson curriculum diet, exercise, behavior
  modification
• Flexible, individualized

Cost 104,000,000
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• Reductions Metformin 31, Lifestyle 58

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Medical causes

• Hypothyroidism
• Underactive thyroid
• Cold intolerance, fatigue, swelling
• Cushings syndrome
• Central obesity, moon face, stretch marks
• Insulinoma
• Hypothalamic damage
• Head injury, surgery, infections

Uncommon!
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Atkins diet

• High protein, low carbohydrate
• Ketone production not demonstrated to occur
• Greater weight loss at 6 but not 12 months
  compared to conventional diet
• High dropout rates in both groups

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Optifast (Modifast) diet

• Liquid high-protein, low carbohydrate
• Induces ketone formation
• Can supplement with vegetables
• 3 months on, 6 months off
• Appetite suppressants required when off
• Very effective 7-8 kg loss per month
• Difficult to adhere to
• Roles
• Weight loss before surgery
• Last resort if not suitable for surgery

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Drug treatment

• Multiple hormones/neurotransmitters involved
  redundancy
• Weight gain when stopped
• Effectiveness similar for all
• Weight plateaus after several months
• Expensive
• Not covered by PBS

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Orlistat (Xenical)

• Inhibits absorption of fat
• Take before meals
• Diarrhoea after eating fat
• Expensive 160/month
• 1kg per month. 12 had 10 loss
• Non-toxic
• Vitamin deficiencies

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Sibutramine (Reductil)

• Affects appetite centre in brain
• Once daily
• Stimulant. Hypertension
• Avoid in epilepsy
• Need to monitor blood pressure
• Similar effectiveness to Xenical
• 15 had 10 weight loss

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Phentermine (Duromine)

• Stimulant
• Cheaper than others (68/month)
• Often not tolerated because of side effects
• Avoid in cardiac disease, hypertension
• Interacts with other drugs

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Conclusions

• Lack of exercise major problem
• Sensible diet avoid fat simple sugars
• Drugs have limited effectiveness, highly
  effective in some
• Surgery sustained weight loss, for more severe
  end of spectrum
• Modifast short-term, individuals with serious
  complications