1. Obesity
is a state of excess adipose tissue mass.
BMI ≥30 obesity
BMI ≥ 25 overweight
abdominal (android or apple-shaped) obesity
generalized (gynoid or 'pear-shaped)
obesity

2. Obesity
Many complications of obesity, as insulin resistance, diabetes, hypertension, hyperlipidemia, are linked more strongly to intraabdominal than to overall adiposity.

3. Obesity
Prevalence
30.5% American adult population had obesity
64% of U.S. adults were overweight
4.7% of the population Extreme obesity
Obesity is more common in women and in the poor.

4. Factors control the appetite

5. Factors released from the adiposity tissue

6. Obesity
Etiology
The environmental factors
plays a key role in obesity
Evidence
Famine protect against obesity
Recent and rapid increase in the prevalence of obesity

7. Obesity
Factors increase prevalence
Increasing energy intake
↑ Portion sizes
↑ Snacking and loss of regular meals
↑ Energy-dense food (mainly fat)
↑ Affluence
Decreasing energy expenditure
↑ Car ownership
↓ Walking to school/work
↑ Automation; ↓ manual labour
↓ Sports in schools
↑ Time spent on video games and watching

8. genes influence the susceptibility to obesity
The genetic factors
genes influence the susceptibility to obesity
Evidence:
Obesity is commonly seen in families
identical twins have very similar BMIs
Obesity is part of specific genetic syndromes (Laurence-moon biedl)

9. Obesity
Gene mutation detected
ob gene coding the peptide leptin.
High leptin levels decrease food intake
increase energy expenditure.
Db gene coding leptin receptor.(leptin resistant)
POMC coding proopiomelanocortin ( neuropeptides)

10. Obesity
To date, there is no evidence to suggest that mutations in the leptin or leptin receptor genes play a prominent role in common forms of obesity

11. Obesity
Secondary causes (reversible)
Endocrine factors
Hypothyroidism
Hypothalamic tumours or injury
Cushing's syndrome
Insulinoma
Drug treatments
Corticosteroids
Tricyclic antidepressants
Sulphonylureas
Sodium valproate
Oestrogen-containing contraceptive pill
β-blockers

12. Obesity
Complications
Obesity is associated with an increase in mortality, mostly due to cardiovascular causes
Mortality rates rise as obesity increases
Obesity related 300,000 deaths per year.
Life expectancy shortened by( 2–5 years) moderately obese
BMI > 45 may lose 13 years of life.

13. Obesity
Complications
Metabolic complications:
Insulin resistance, diabetes type 2, hyperlipidemia
Most obese individuals do not develop diabetes.
80% of patients with type 2 diabetes mellitus are obese
Increase the risk coronary heart disease, Stroke

14. Obesity Metabolic syndrome
Central obesity: waist circumference ≥ 94 cm (male)
≥ 80 cm (female)
AND any two of the following
Raised triglycerides: > 150 mg/dL,
Reduced HDL cholesterol < 40 mg/dL in males,
< 50 mg/dL in females
Raised blood pressure
systolic BP > 130 or diastolic BP >85 mm Hg
Raised fasting plasma (FPG): >100 mg/dL or previously diagnosed type 2 diabetes

15. Obesity
2. Cardiovascular Disease
coronary disease
stroke
congestive heart failure (CHF)
atherogenic lipid profile
increase (LDL) ,VLDL, and triglyceride.
decreased HDL
Hypertension
increased peripheral resistance, cardiac output
increased sympathetic nervous system tone
increased salt sensitivity, and insulin-mediated salt retention

16. Downloaded from: StudentConsult (on 6 December 2011 05:10 PM)
© 2005 Elsevier

17. Obesity
3. Endocrine Disorders :
In men :
plasma testosterone often reduced
estrogen levels increased
Gynecomastia may be seen.
In women:
menstrual abnormalities
increased androgen
increased conversion of androgen to estrogen.
oligomenorrhea
polycystic ovarian syndrome (PCOS)

18. Obesity
4. Pulmonary Disease:
Exertional dyspnoea Sleep apnoea Respiratory failure (Pickwickian syndrome)
caused by (restrictive ventilation)
reduced chest wall compliance
decreased functional residual capacity and expiratory reserve volume

19. Obesity
5. Gastrointestinal  :
Gallstones: cholesterol gallstones
caused :
enhanced biliary secretion of cholesterol
supersaturation of bile
nonalcoholic fatty liver disease :
simple steatosis
steatohepatits
cirrhosis
Gastroesophageal reflux disease:

20. 6. Musculoskeletal : increased risk of osteoarthritis
Obesity
6. Musculoskeletal : increased risk of osteoarthritis
7.Skin :
Skin infection (submammary Candida)
varicose vein
8. cancer: colorectal CA, uterine CA, breast CA
9. Psychological : depression, Social stigmatization
10. Socioeconomic : low income, unemployment

21. Thanks