Upload
dr-bedangshu-saikia
View
223
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Causes, Pathophysiology and Management Strategies of Childhood Obesity
Citation preview
Obesity in Children
Dr. Bedangshu SaikiaRegistrar, Pediatrics and Neonatology
St Stephens Hospital, New Delhi
Obesity
is a condition of abnormal or excessive fat
accumulation in adipose tissue to the extent that
health may be impaired
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
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)
International Scenario
Pathogenesis
Thrifty genotypeSedantary lifestyleGood high calorie food
Measurement of obesityFat cannot be measured.
The best way to measure obesity is Body Mass Index in
adults
Measurement of obesityBut in children age and gender reference charts of BMI
are availableBMI > 85th percentile – OverweightBMI > 95th percentile (+2SD) – ObeseIn children < 2 Years wt. for length charts are usedOther methods to measure obesity:
Skin fold thicknessWaist hip ratio (more in adults)Waist circumference (more in adults)
Some imaging studies (DEXA, USG, CT scan, MRI, Bioelectrical impedance)
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
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
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
Endogenous causes
Endocrinal causes1. Cushing’s syndrome2. Hypothyroidism3. Hyperinsulinism4. Pseudo-
hyperparathyroidism5. Acquired
hypothalamic syndrome
Genetic Causes1. Prader Willi syndrome2. Alstrom3. Carpenter4. Cohen5. Laurence Moon Biedl
Diseases Associated with Childhood Obesity (Endogenous obesity)
Exo – versus Endogenous CausesEndogenous Obesity1. Family history
uncommon2. Short height3. Low IQ4. Retarded bone age5. Physical defects
common
Exogenous Obesity1. Family history of
obesity2. Tall child3. Normal IQ4. Normal bone age5. Normal physical exam
Causes of Exogenous Obesity
Genetic
Environmental
Dietary
Neurochemical
Malnutrition
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
Genes for obesity
Ob GeneProduct – leptinReduces appetite, increases metabolic rate, increases fat oxidationMutation results in decreased leptin output leading to obesity
Genes of Obesity – Contd..
db Gene Regulates leptin binding siteEstablishes ‘set point’Fat GeneProduces carboxypeptidasesCauses miss processing of insulin – competes with
leptin binding
Genes of Obesity - Contd..
tub GeneUnknown product – possibly mitochondrial
uncoupling proteinAgouti GeneProduct – agouti signaling proteinSuppresses appetite during weight gain
Pathway through which leptin acts to regulate appetite and body weight
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)
Environmental factors
Vigorous feeding
Sedentary lifestyle
TV viewing
- lowers the metabolic rate
- increased caloric intake during viewing
- Food advertisements and messages
Dietary Factors
Reduced meal frequency and ‘gorging’ promotes
weight gain, in contrast to ‘nibbling’
High calorie dense foods
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
Control of appetite
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
Complications of Obesity
Medical
Orthopedic
Dermatologic
Psychosocial
Endocrinologic
Medical Complications
Hypertension
Hyperlipidemias
Coronary heart disease
Cholelithiasis and steatohepatitis
Respiratory infections
Obesity hypoventilation syndrome
Obstructive sleep apnea
Orthopedic ComplicationsIN CHILDREN
Slipped femoral epiphysis
Legg-Calves-Perthes’ Disease
Genu valgum
IN ADOLESCENT
Blount disease (slipped tibia vara)
Slipped femoral epiphysis
Dermatologic Complications
Heat rash
Intertrigo
Monilial dermatitis
Striae
Acanthosis nigricans
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
Endocrinologic Complications
Hyperinsulinemia with insulin resistance
- Overt diabetes
- Stimulates lipogenesis and maintains obesity
- Hyperplasia and hypertrophy of fat cells
Endocrinologic Complications
Decreased SHBG (Sex hormones binding globulin)
↓ Increase free sex hormones
↓Early puberty and advanced skeletal age
Endocrinologic Complications
Increased urinary clearance of cortisol
↓Compensatory increase in ACTH
↓Increased adrenal sex steroids
↓Early adrenarche
Office evaluation of an obese childObjective :differentiate between Organic causes and Idiopathic
obesity and early detection of complications
History
Physical Examination
Laboratory Studies
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
History
Family history of CHD, cancer, diabetes,
hypertension, hyperlipidemia and thyroid disorders
History of complications
Psychosocial history and evaluation
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
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)
Simplified Laboratory Norms for Assessing Overweight Children
Comorbidity H & PE Testing
Management of Obesity
Goals of treatment
Dietary management
Exercise
Behaviour modification
Other treatments
Complications of treatment
Management of Obesity
Successful treatment of obesity is challenging
Treatment goals vary- depending on
the age of the child and
the severity of complications
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
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.
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
Proposed Algorithm for Weight Management
2-7 Yrs > 7 Yrs
BMI85-94 %ile
BMI> 95%ile
BMI85-94 %ile
BMI> 95%ile
Weightmaintenance
Complication
No Yes
Weight loss
Complication
No
Weightmaintenance
Yes
Weight loss
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.
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.
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
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.
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)
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
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.
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
Dietary Management
ExerciseDecreasing 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
Exercise
Preserves lean body mass
Prevents the reduction in BMR associated with
weight loss
Improvement in mood
Promotes a more active lifestyle in adulthood
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
Behavior ModificationPsychologists 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.
Behavior ModificationTechniques
Changes in the home and family environment
Nutrition education
Self monitoring
Goal setting
Stimulus control procedures
Contracting
Parenting skills training
Positive reinforcement,,
Other Treatments
Anti-obesity drugs
Surgery
Leptin therapy
Medication of overweight children and adolescents is reserved for those with severe medical complications.
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
Bariatric Surgery Timing of surgical TreatmentSexual 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
LAGB
BPD
BPDDS
RYGB
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
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
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
Proposed Suggestions for the Prevention of Obesity
Proposed Suggestions for the Prevention of Obesity
Thank you