What is Obesity?

Obesity means excess accumulation of fat in the body

Once it develops it is difficult to ‘cure’ and usually persists throughout life

Obesity is usually diagnosed on the basis of calculation of

Body mass index Measurement of waist-hip ratio

Classification of Overweight and Obese by Body Mass Index

BMI (kg/m2)

WHO guidelines Proposed Asia Pacific guidelines Underweight < 18.5 < 18.5

Normal 18.5-24.9 18.5-22.9

Overweight 25.0-29.9 > 23

At risk - 23-24.9

Obesity 30-34.9 (Class I) 25-29.9 (Class I)

35-39.9 (Class II) > 30 (Class II)

Extremely Obese > 40 (Class III) -

BMI = Weight (kg) [Height (m)]2

Waist-to-hip ratio

Ratio = WAIST

HIPS

TO FIND RATIOWaist: Measure atnarrowest point withstomach relaxed

Hips: Measure atfullest point

Desired RatioWomen : <0.8Men : < 1.0

Risk increases if waist circumference is >94 cm in men and >80 cm in women

Co-morbidities risk associated with different levels of BMI and suggested waist circumference in adult Asians

Classification BMI Risk of co-morbidities

Waist circumference

< 90 cm (men) > 90 cm (men)

< 80 cm (women) > 90 cm (women)

Underweight < 18.5 Low Average

Normal range 18.5-22.9 Average Increased

Overweight > 23

At risk 23-24.9 Increased Moderate

Obese I 25-29.9 Moderate Severe

Obese II > 30 Severe Very severe

Obesity – An imbalance in energy intake and energy expenditure

Proteins (20%) BMR (60-65%)

ENERGY INTAKE ENERGY EXPENDITURE

Carbohydrates (55%) Physical activity (25-30%)

Fats (25%) Thermic effectof food (10%)

Classification of obesity as per fat distribution

Android (or abdominal or central, males)-Collection of fat mostly in the abdomen (above the waist)

-apple-shaped

-Associated with insulin resistance and heart disease

Gynoid (below the waist, females)

• Collection of fat on hips and buttocks

•pear-shaped

-Associated with mechanical problems

Diseases and conditions forwhich obesity is a risk factor

Coronary artery disease**

Type II Diabetes Mellitus***

Hypertension**

Dyslipidemia***

Respiratory disease***

Gout**

Reflux disease

Psychological problems

Gallbladder disease***

Osteoarthritis**

Infertility*

Venous circulatory disease

Increased anaesthetic risk*

Low back pain*

Polycystic ovary disease*

Cancer* (ovarian, breast, endometrial, gallbladder, prostate, colon)

Prevalence of overweight and obesity in different income groups of Delhi (Nutrition Foundation of India Study)

Prevalence (%)

Slums Middle-Class Total

Overweight (BMI > 25)Males ND ND 19.6Females ND ND 44.5

Obesity (BMI > 30)Males 1 32.3 NDFemales 4 50 ND

Abdominal obesityMales ND 49.7 NDFemales ND 34.9 ND

ND: Not determined

http://www.nutritionfoundationin.org/NEW/OBESITY.HTM

The Five City Study

n=3257; aged 25-64 yrs

Cities: Moradabad (n=902), Trivandrum (n=760), Calcutta (n=410), Nagpur (n=405), Bombay (n=780)

Social Class BMI>27 WHR>0.85 Sedentary life style

I (n=985) 21.2% 96.9% 92.2%

II (n=790 16.4% 57.2% 71.4%

III (n=674) 8.9% 39.3% 42.3%

IV (n=602) 3.0% 11.9% 14.9%

V (n=206) 3.8% 8.7% 8.7%

Int J Cardiol 1999;69:139-147

Advantages of weight loss

Weight loss of 0.5-9 kg (n=43,457) associated with 53% reduction in cancer-deaths, 44% reduction in diabetes-associated mortality and 20% reduction in total mortality

Survival increased 3-4 months for every kilogram of weight loss

Reduced hyperlipidemia, hypertension and insulin resistance

Improvement in severity of diseases Person feels ‘fit’ and mentally more active

 

Treatment goals

Prevention of further weight gain

Weight loss to achieve a realistic, target BMI

Long-term maintenance of a lower body-weight

How much weight loss is significant?

A 5-10% reduction in weight (within 6 months) and

weight maintenance should be stressed in any weight

loss program and contributes significantly to

decreased morbidity

Diet Activity Drugs VLCD Surgery

BMI 23-25

No risk factors

DM/CHD/HT/HL

-

BMI 25 – 30

No risk factors

DM/CHD/HT/HL

(consider)

BMI > 30

No risk factors

DM/CHD/HT/HL

(in

severe)

(consider

in severe)

Approaches to obesity management

Drug therapy

Appetite suppressants Adrenergic agents (e.g. amphetamine, methamphetamine,

phenylpropanol amine, phentermine) Serotonergic agents (e.g. fenfluramine, dexfenfluramine,

SSRIs like sertraline, fluoxetine)

Thermogenic agents ephedrine, caffeine

New ones Sibutramine ; Orlistat

Noradrenaline Serotonin

Sibutramine inhibits serotonin andnoradrenaline reuptake

STORM Study : Effect of sibutramine on weight loss

98

104102100

96949290

0 12 22 2420181614108642

Placebo

Sibutramine

Month

Weight loss Weight maintenance

Bod

ywei

ght (

kg)

Lancet 2000; 356:2119-2125

STORM Study:Effect on Waist Circumference and Waist/Hip Ratio

-9.2

-4.5

-10

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

Sibutramine Placebo

Dec

rea

se in

wai

stci

rcum

fere

nce

(cm

)

-1.2

0.8

-1.5

-1

-0.5

0

0.5

1

Sibutramine Placebo

Cha

nge

(a) Waist Circumference (b) Waist/Hip Ratio

STORM Study : Effects on lipids

50

-5-10-15-20-25

Placebo

Sibutramine

Triglycerides

% c

han

ge

00 2418126

50

-5-10-15-20-25

Placebo

Sibutramine

VLDL cholesterol

180 24126

% c

han

ge

Lancet 2000; 356:2119-2125

STORM Study : Effects on lipids (Contd.)

180 24126

25

20

15

10

5

0

HDL cholesterol

% c

ha

ng

e Sibutramine

Placebo

Month of assessment

Weight loss

Weight maintenance

Lancet 2000; 356:2119-2125

30

STORM study: Conclusions

Almost all patients who persist with a weight management program consisting of sibutramine, diet and exercse can achieve at least a 5% weight loss with sibutramine

Over half can lose more than 10% weight within 6 months

Weight loss was sustained in most patients continuing therapy for two years

Sibutramine vs. Dexfenfluramine

-3.2

-4.5-5-4.5

-4-3.5

-3-2.5

-2-1.5

-1-0.5

0

We

igh

t los

s (k

g)

Sibutramine 10 mg Dexfenfluramine 30 mg

n=226; 12 wks

Int J Obes 1995; 19. Suppl 2: 144

Adverse effects occurring in >5% of patients treated with Sibutramine compared with placebo

Sibutramine % Placebo %Adverse Effects Incidence (n=2068) Incidence (n=884)

Headache 30.3 18.6

Dry Mouth 17.2 4.2

Anorexia 13.0 3.5

Constipation 11.5 6.0

Insomnia 10.7 4.5

Dizziness 7.0 3.4

Nausea 5.9 2.8

Nervousness 5.2 2.9

Dyspepsia 5.0 2.6

Ann Pharmacother 1999;33:968-978

STORM Study :Withdrawals due to BP increase

Dose of Sibutramine % patients who

withdrew due to

increase in BP

10 mg 1%

15 mg 2%

20 mg 3%

Lancet 2000; 356:2119-2125

Indications & Dosage

Recommended for obese patients with a BMI > 30 kg/m2 or > 27 kg/m2 in the presence of other risk factors (e.g. hypertension, diabetes, dyslipidemia)

In Indian patients, sibutramine could be considered in patients with BMI > 25 kg/m2 or those with BMI of 23 kg/m2

with comorbid conditions Recommended starting dose is 10 mg once daily. If there is inadequate weight loss, the dose may be titrated

after four weeks to a total of 15 mg once daily. The 5 mg dose should be reserved for patients who do not

tolerate the 10 mg dose.