growth & obesity - royal children's hospital · • cause may not yet be discovered –...

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Growth &Obesity

Matt Sabin

25TH May 2010

GrowthFactors affecting longitudinal growth;• Nutrition

• affected by general health, hormone balance (leptin/insulin/gut hormones etc)

• General Health• Normal skeleton• GH/IGF1 axis• Insulin• Sex steroids• Adrenal function• Thyroid status

CHILDHOOD= GH/nutrition

PUBERTAL= GH/sex hormones

FETAL = nutrition/growth factors

Infant growth – predominantly nutritionally driven

Childhood growth – predominantly GH/IGF axis dependent

Considerable overlap…

Pubertal growth – androgen/oestrogen dependentImportance of monitoring…

Measuring…• <2 – supine table with 2 measurers

• >2 – stadiometer – mastoid elevation

• Proportions – arm span to height (=1)

• Upper:Lower segments– 1.7 as a neonate– 1.4 by 4-5 years– 1.0 by 10-12 years

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IGF System

Short stature

Genetic Short Stature

• Determine parental target height• Growth velocity• Not an absolute diagnosis

– If the parents are short and the child is short then mayIf the parents are short and the child is short then may be due to the inheritance of a genetically transmitted disorder

• Eg endocrine causes (pseudohypoparathyroidism, thyroid problems), osteochondrodysplasias, renal disease, blood disorders such as thalassaemias etc

• Cause may not yet be discovered – GH/IGF Axis abnormalities

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CDGP• Exclusion of other causes of SS along with late maturation

• FH delayed puberty is often present

• Parental anxiety/Distress to child should not be underestimated

MATURATIONAL DELAY

FAMILIAL SHORT STATURE

SHORT SLOW GROWTH DELAYED PUBERTY DELAYED BA HA =BA GOOD HEIGHT PROGNOSIS

SHORT NORMAL GROWTH NORMAL PUBERTY BA NOT DELAYED HA<BA POOR HEIGHT PROGNOSIS

Pathological Growth Failure

• E NDOCRINE• P sychosocial• I atrogenic • C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal


• ENDOCRINE• P sychosocial• I atrogenic • C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal


• ENDOCRINE• P sychosocial• I atrogenic• C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal

Endocrinea. Hypothyroidismb. Cushing Syndromec. Pseudohypoparathyroidismd. Ricketse. IGF deficiency

a. GH deficiency due to hypothalamic dysfunctionb. GH deficiency due to pituitary GH deficiencyc. GH insensitivity (Primary or Secondary)d. Primary defects in IGF synthesise. Primary defects in IGF transport/clearancef. IGF resistance

a. Defects of the IGF-1 receptorb. Post-receptor defects


• ENDOCRINE• P sychosocial• I atrogenic• C hromosomal• C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal

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• ENDOCRINE• P sychosocial• I atrogenic - Steroids/Radiotherapy• C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal


• ENDOCRINE• P sychosocial• I atrogenic• C hromosomal - Turner• N utritional• I ntrauterine• C hronic Disease• S keletal

Chromosomal abnormalitiesTurners syndrome

(always think of Turners in a girl with short stature)

Noonan’s Down Syndrome


• ENDOCRINE• P sychosocial• I atrogenic • C hromosomal • N utritional• I ntrauterine• C hronic Disease• S keletal


• ENDOCRINE• P sychosocial• I atrogenic

Fetal abnormalities- chromosomal abn, syndromes such as Russell Silver, Noonan’s, Progeria, Prader-Willi etc, congenital infections• I atrogenic

• C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal

, g

Placental abnormalities- (commonest cause = impaired uteroplacental function)

Maternal disorders- (malnutrition, diabetes, hypertension, alcohol, drugs)

Non-dysmorphic IUGR babies exhibit catch up growth by age of 5 years in 80-85% of cases


• ENDOCRINE• P sychosocial• I atrogenic - Steroids/DXRT• C hromosomal - Turner• C hromosomal - Turner• N utritional• I ntrauterine• C hronic Disease eg. Diabetes, CF, Asthma• S keletal

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• ENDOCRINE• P sychosocial• I atrogenic• C hromosomal• N utritional• I ntrauterine• C hronic Disease• S keletal

OsteochondrodysplasiasOver 100 conditionsAchondroplasia is the commonest

AD but 90% are new mutationsFGFR mutationAchondroplasia growth curves available

Baseline investigations• Clinical judgement – not every Ix is needed!!

– May be just a Bone Age

• Clinical features suggesting Ix’s may be warranted;;– Extreme short stature– Height significantly below target height– Subnormal height velocity– History of chronic disease– Obvious dysmorphic syndromes (Turner’s/Noonan’s)– Precocious or abnormally delayed puberty– ??Extreme parental concern

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Failure to grow with GH therapy• Technical problems

– Measurement errors– Poor compliance– Improper preparation / handling / storage– Incorrect injection technique– Incorrect GH dosage

• Other conditions– Subclinical hypothyroidism– Chronic Disease or poor nutritional status– Glucocorticoid therapy for any reason– Hx of irradiation of the spine– Previous epiphyseal fusion

• Failure of GH effect– Anti GH antibodies– GH Resistance Syndromes– Incorrect diagnosis and child not actually GH deficient

Tall statureTall stature

Tall Stature“COMMON” CAUSES:

•Idiopathic- Familial (tall parents) (normal GV

and bone age)

- Early puberty

- Obesity- Obesity

•Thyrotoxicosis

•Early Puberty

•Obesity

•Klinefelter

“Rare” causes: overgrowth syndrome (eg Soto’s, Marfan’s, BW)GH secreting pituitary tumour

Investigations

• If physical examination normal, no intellectual delay and tall family – none

• Otherwise consider;B– Bone age

– Karyotype, Thyroid function, IGF-1– If GH secreting pituitary tumour suspected

(rare!) then examine visual fields + do OGTT for GH secretion +/- MRI

Tall Stature - An approach

•MANAGEMENT

• Treat specific cause

• Counselling

• Rarely accelerate puberty in boys or girls with either testosterone or oestrogen respectively

BUT potential risks and therefore rarely used

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Obesityy Obesity trends in the U.S.Obesity trends in the U.S.

Obesity Trends* Among U.S. AdultsBRFSS, 1985

(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person)

No Data <10% 10%–14%



No Data <10% 10%–14%



No Data <10% 10%–14%



No Data <10% 10%–14%

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No Data <10% 10%–14%



No Data <10% 10%–14%



No Data <10% 10%–14% 15%–19%



No Data <10% 10%–14% 15%–19%



No Data <10% 10%–14% 15%–19%



No Data <10% 10%–14% 15%–19%

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No Data <10% 10%–14% 15%–19%



No Data <10% 10%–14% 15%–19%



No Data <10% 10%–14% 15%–19% ≥20



No Data <10% 10%–14% 15%–19% ≥20



No Data <10% 10%–14% 15%–19% ≥20



No Data <10% 10%–14% 15%–19% ≥20

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No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

(*BMI ≥30, or ~ 30 lbs overweight for 5’4” person)(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person)


No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

Obesity* Trends Among U.S. AdultsBRFSS, 2003


No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

growth & obesity - royal children's hospital · • cause may not yet be discovered –...

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