Causes, Pathophysiology and Management Strategies of Childhood Obesity

1. Obesity in Children
Dr. Bedangshu Saikia
Registrar, Pediatrics and Neonatology
St Stephens Hospital, New Delhi

2. Obesity
is a condition of abnormal or excessive fat
accumulation in adipose tissue to the extent that
health may be impaired

3. An emerging problem reaching epidemic proportions.
A big health problem which affects not only their
childhood but also causes problems in their adult life.
Between 3-7% of total health care costs can be
attributed to overweight.
It is prevalent not only in developed but also in
developing countries

4. Indian Scenario
Increasing prevalence of obesity in adolescents especially in urban affluent
population (22% overweight in affluent schools as compared to 4.5% in poor section
schools)
Pune Study: (1228 boys between 10-15 Years)
25.1% overweight and 8.1% obese
Delhi :
31% of children overweight and 7.5% obese (Private schools)
 29% overweight with BMI >25 (In 5000 children between 4-18 Years
showed)

5. International Scenario

6. Pathogenesis
Thrifty genotype
Sedantary lifestyle
Good high calorie food

7. Measurement of obesity
Fat cannot be measured.
The best way to measure obesity is Body Mass Index in
adults

8. Measurement of obesity
But in children age and gender reference charts of BMI
are available
BMI > 85th percentile – Overweight
BMI > 95th percentile (+2SD) – Obese
In children < 2 Years wt. for length charts are used
Other methods to measure obesity:
Skin fold thickness
Waist hip ratio (more in adults)
Waist circumference (more in adults)
Some imaging studies (DEXA, USG, CT scan, MRI, Bioelectrical
impedance)

10. Do obese children grow into
obese adults?
‘Tracking’ occurs throughout life
10-20% obese infants
40% obese children
60-80% obese adolescents
“Adiposity rebound”
Obese Adults

11. Types of Obesity
Android Obesity/
Central Obesity
- Fat accumulates in
the upper segment
- Apple shaped
distribution
- More likely to
develop related disorders
like NIDDM, HT, etc.
- WHR (waist hip
ratio) > 0.8
Gynecoid Obesity
- More subcutaneous
fat
- Accumulates over
thighs and lower
segment
- Pear shaped
- Complications fewer

13. Causes of Obesity
Endogenous causes comprise of genetic and
endocrine causes – responsible for less than 10% cases
(<5%- Nelson 18e)
Should be ruled out before treating as exogenous
obesity

14. Endogenous causes
Endocrinal causes
1. Cushing’s syndrome
2. Hypothyroidism
3. Hyperinsulinism
4. Pseudo-hyperparathyroidism
5. Acquired
hypothalamic
syndrome
Genetic Causes
1. Prader Willi syndrome
2. Alstrom
3. Carpenter
4. Cohen
5. Laurence Moon Biedl

15. Diseases Associated with Childhood Obesity
(Endogenous obesity)

16. Exo – versus Endogenous Causes
Endogenous Obesity
1. Family history
uncommon
2. Short height
3. Low IQ
4. Retarded bone age
5. Physical defects
common
Exogenous Obesity
1. Family history of
obesity
2. Tall child
3. Normal IQ
4. Normal bone age
5. Normal physical exam

17. Causes of Exogenous Obesity
Genetic
Environmental
Dietary
Neurochemical
Malnutrition

18. Genetic Causes
Strong correlation between the bodyweight of the
child and biological parents
Resting energy expenditure genetically determined –
influences obesity
A number of genes shown to be involved
Discovery of leptin – big bang in the field of obesity

19. Genes for obesity
Ob Gene
Product – leptin
Reduces appetite, increases metabolic rate,
increases fat oxidation
Mutation results in decreased leptin output
leading to obesity

20. Genes of Obesity – Contd..
db Gene
Regulates leptin binding site
Establishes ‘set point’
Fat Gene
Produces carboxypeptidases
Causes miss processing of insulin – competes with
leptin binding

21. Genes of Obesity - Contd..
tub Gene
Unknown product – possibly mitochondrial
uncoupling protein
Agouti Gene
Product – agouti signaling protein
Suppresses appetite during weight gain

23. Pathway through which leptin acts to regulate appetite and body weight

24. Environmental Factors
In the first year – duration of feeding
- age of introduction of
solid foods
Second year – maternal weight (reflects the maternal
influence on child’s intake and expenditure)

25. Environmental factors
Vigorous feeding
Sedentary lifestyle
TV viewing
- lowers the metabolic rate
- increased caloric intake during viewing
- Food advertisements and messages

26. Dietary Factors
Reduced meal frequency and ‘gorging’ promotes
weight gain, in contrast to ‘nibbling’
High calorie dense foods

27. Neurochemical Causes
Feeding and appetite closely regulated – imbalance
may lead to obesity
Factors include insulin, neuropeptide Y, dopamine
and other monoamines, serotinin, and gut hormones
like CCK

28. Control of appetite

29. Malnutrition
Prenatal malnutrition predisposes to obesity –
due to altered development of hypothalamus and
the sympathetic system
 Dutch famine of the Second WW
Undernutrition in later life – tendency to
accumulate fat more rapidly and intra
abdominally

31. Complications of Obesity
Medical
Orthopedic
Dermatologic
Psychosocial
Endocrinologic

32. Medical Complications
Hypertension
Hyperlipidemias
Coronary heart disease
Cholelithiasis and steatohepatitis
Respiratory infections
Obesity hypoventilation syndrome
Obstructive sleep apnea

33. Orthopedic Complications
IN CHILDREN
Slipped femoral epiphysis
Legg-Calves-Perthes’ Disease
Genu valgum
IN ADOLESCENT
Blount disease (slipped tibia vara)
Slipped femoral epiphysis

34. Dermatologic Complications
Heat rash
Intertrigo
Monilial dermatitis
Striae
Acanthosis nigricans

35. Psychosocial Complications
Most serious consequence
Lower self image, heightened self consciousness,
impaired social functioning
Negative stereotype attributed by peer group and
even trained physicians
Less likely to be successful in life

36. Endocrinologic Complications
Hyperinsulinemia with insulin resistance
- Overt diabetes
- Stimulates lipogenesis and maintains obesity
- Hyperplasia and hypertrophy of fat cells

37. Endocrinologic Complications
Decreased SHBG (Sex hormones binding globulin)
↓
Increase free sex hormones
↓
Early puberty and advanced skeletal age

38. Endocrinologic Complications
Increased urinary clearance of cortisol
↓
Compensatory increase in ACTH
↓
Increased adrenal sex steroids
↓
Early adrenarche

39. Office evaluation of an obese child
Objective :
differentiate between Organic causes and Idiopathic
obesity and early detection of complications
History
Physical Examination
Laboratory Studies

40. History
Duration of disease
Previous attempts at weight reduction
Daily caloric intake and expenditure
Family history
- attitudes and practices
- weight status of parents and siblings
- meal patterns and recreational habits

41. History
Family history of CHD, cancer, diabetes,
hypertension, hyperlipidemia and thyroid disorders
History of complications
Psychosocial history and evaluation

42. Physical Evaluation
Assessment of growth of the child
Distribution of fat - gynecoid or android
Sexual Maturity Rating (SMR) scoring
Blood Pressure
Other clinical features of organic causes

43. Laboratory Studies
Evaluation of pituitary, adrenal, and thyroid
hormones for endocrine dysfunction (selective)
Blood glucose and insulin levels
Plasma lipids
Serum cholesterol in all >2 years (NCEP expert panel)

44. Simplified Laboratory Norms for
Assessing Overweight Children

45. Comorbidity H & PE Testing

47. Management of Obesity
Goals of treatment
Dietary management
Exercise
Behaviour modification
Other treatments
Complications of treatment

48. Management of Obesity
Successful treatment of obesity is challenging
Treatment goals vary- depending on
the age of the child and
the severity of complications

49. Goals of Treatment
Achieve lifelong weight control
Avoid weight cycling
Maintain normal growth
Metabolically safe
Minimal hunger
Preserve lean body mass
No psychological problems
IAP

50. Goals of treatment
In most children these goals can be attained by just
maintaining weight, rather than weight loss
Weight loss should be slow (1 lb or 0.5 kg or less/wk)
It should be attempted only in skeletally mature children
or in those with serious complications from obesity.
An initial goal -10% reduction in weight
Once achieved, the new weight should be maintained for
6 mo before further weight loss is attempted.

51. Goals of treatment
Most successful approach to weight maintenance or
weight loss requires
substantial lifestyle changes that include
 increased physical activity and
 altered eating habits

52. Proposed Algorithm for Weight
Management 2-7 Yrs > 7 Yrs
BMI
85-94 %ile
BMI
> 95%ile
BMI
85-94 %ile
BMI
> 95%ile
Weight
maintenance
Complication
No Yes
Weight
loss
Complication
No
Weight
maintenance
Yes
Weight
loss

53. Multidisciplinary and community
based management 1
 Severely overweight children and adolescents with complications from
obesity are best managed by a multidisciplinary team.
 Teams may include a physician, a psychologist, a dietitian, an exercise
specialist (physical therapist, exercise physiologist, educator), a nurse,
and counselors.
Management consists of dietary counseling, exercise therapy, and
behavioral management.
 The treatment models used in most pediatric centers feature family-based
behavioral treatment, which is the only approach shown to have
long-term efficacy.

54. Dietary Management
Recommending healthy eating - should be age specific
and flexible enough
The parents should be educated about approaches to
deal with food refusals
Often more than 10 repeated exposures are required to a
new food before a child will regularly accept it as part of
the regular diet.

55. Dietary Management
Simple measures:
For older than 2 yrs: Changing to skim milk,
exposure to a wide variety of less calorie-dense
foods and limitation of between-meal snacking.
Sweetened beverages should be limited and
parents should continue to offer healthy foods

56. Dietary Management
Encouraging breakfast, decreasing sweetened beverages,
and teaching the principles of balanced nutrition (eating
from all food groups) are useful strategies for school
going and overweight adolescent.

57. Dietary Management
Diet must provide all essential nutrients
Calculate caloric intake on the principle that
O.5 Kg of wt loss = 3500 kcal deficit
Replace fat with complex carbohydrates (Low glycemic
Index)
Increase fiber (intake = age + 5-10 gm/day)

58. Dietary Management
 Special Diets:
1. Balanced Hypocaloric diet
- Provide 30-40% less than usual intake with lower fat (25-30%),
more (50-55%) complex carbohydrate, and sufficient
protein (20-25%)
- ensures normal growth with weight loss of upto 0.5 kg/week

59. Dietary Management
 Special Diets: for severe obesity
2. Restrictive protein sparing modified fast diet (ELCD)
- Provides only 600-800 kcal/day (1.5-2 g/kg protein, 2 L
water, 2-4 cup low starch veg
- Achieves faster weight loss
- More side effects like orthostatic hypotension,
arrhythmias, hair loss etc.

60. Dietary Management
 Needs a multidisciplinary approach:
 identify problem areas in a child's and family's regular diet
 teach them about healthier alternatives and eating patterns
 Traffic light or stoplight diet:
 successful approach used in preschool and preadolescent children.
 limit calories
 achieve good nutrient balance and
 easily adaptable to fit particular ethnicities and nutrition plans

61. Dietary Management

62. Exercise
Decreasing sedentary activity is essential for achieving weight
control.
Increased activity not only increases calorie use but also
appears to decrease appetite.
Children younger than 2 yrs,
avoiding television and computers
Children 2–18 yr of age
should have <2 hr/day of “screen time” (television, video
games, computer), and televisions should be removed from
children's bedrooms

63. Exercise
Preserves lean body mass
Prevents the reduction in BMR associated with
weight loss
Improvement in mood
Promotes a more active lifestyle in adulthood

64. Exercise – Contd..
Long term compliance poor with vigorous exercise
Better option to decrease inactivity
- Less time on computer/ TV
- Using stairs in place of elevators
- Walking to perform daily errands
- Playing outdoor games
In the severely overweight, problems of exercise tolerance,
referral to an experienced physical or exercise therapist for
a safe and graded exercise regimen

65. Behavior Modification
Psychologists screen families for underlying problems that led to
child's overweight,
problems arising from health complications of overweight, and
barriers to successful adaptation of a healthier lifestyle.
Once problems are identified, psychologists and counselors can use
cognitive behavioral and family therapy to address such issues.
The treatment models used was family-based behavioral treatment,
which is the only approach shown to have long-term efficacy.

66. Behavior Modification
Techniques
Changes in the home and family environment
Nutrition education
Self monitoring
Goal setting
Stimulus control procedures
Contracting
Parenting skills training
Positive reinforcement,,

67. Other Treatments
Anti-obesity drugs
Surgery
Leptin therapy

68. Medication of overweight children and adolescents is reserved for those with
severe medical complications.

69. Bariatric Surgery
Surgery to be considered only in children with a
BMI > 40 and
a medical complication of obesity
after they have failed 6 mo of a multidisciplinary weight management
program.
American Pediatric Surgical Association Guidelines
Monitoring for nutritional complications is mandatory
Deficiencies of iron, vitamin B12, folate, thiamine, vitamin D, and
calcium have been reported

70. Bariatric Surgery
Timing of surgical Treatment
Sexual maturation –Tanner 3 or 4
Skeletal maturation – Age 13 – 14 girls, 15-16 boys or has attained
mid parental height.
Congenital maturation – acquired formal operations – thinking
about possibilities consequences
Contradictions:
Substance abuse
Psychiatric disabilities include severe eating disorders
Inability or unwillingness to follow medical or nutritional
recommendations

71. LAGB
BPD
BPDDS
RYGB

72. Complications of Treatment
Gall bladder disease in cases of rapid weight loss
Slowing of linear body growth
Loss of lean body mass
Eating disorders
Emotional and psychological problems

73. Prevention of Obesity
Treating difficult so prevention better
Parents taught to respect the child’s appetite
Food not to be used for comfort or reward
Avoid sugared foods and encourage fiber intake
Restrict sedentary activities like TV viewing
Promote healthy lifestyle by acting as role models

74. Multidisciplinary and community
based management 2
Community-based programs to inform families
regarding age-appropriate healthy
 eating choices,
 meal and portion size planning,
 decreasing “screen time,” and
 approaches to increasing physical activity provide an
important service for families with children at risk for
becoming overweight or mildly to moderately
overweight without comorbidities

75. Proposed Suggestions for the Prevention of Obesity

76. Proposed Suggestions for the Prevention of Obesity

77. Thank
you