Overview. My path. Sex differences. Background. Prenatal testosterone and language development 2/04/2012. Andrew Whitehouse. Autism Research Team

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Prenatal

testosterone

and

language

development

Andrew

Whitehouse

Overview

1. Who

am

I?

2. Background

to

the

area

3. Current

study

– Another terrific longitudinal study!

4. Planned

work

(cerebral

lateralisation)

– Follow‐up study

– Autism PRISM study

5. Conclusions

My

path

Speech Pathologist PhD Oxford Telethon Institute

Me

• Autism

Research

Team

– Research

officers

and

assistants

– PhD

Students

Background

Sex

differences

• Language

development

– Males

<

females

– First

12 months

• Frequency joint attention

• Frequency dyadic interaction

– Rate

of

vocab

development

– Increased

risk

of

DLD

(2)

Sex

differences

• Assuming

sex

differences,

what

may

cause

this?

– Socio

‐

developmental

differences?

• Parental input?

S

ifi

i i fl

– Sex

‐

specific

genetic

influences

• CNTNAP2 (Whitehouse et al., 2011, Genes, Brain, Behavior)

• Influence in a different way

• To a greater or lesser extent

– Another

biological

difference

• Hormones?

Androgens

• Androgens – A generic term that for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of male characteristics in vertebrates by binding to androgen receptors.

1. Testosterone

2. Dehydroepiandrosterone (DHEAS)

3. 4-androstenedione (A4)

Prenatal

testosterone

• How

are

fetuses exposed

to

T?

Endogenous

Exogenous

Males have higher testosterone levels in-utero

Prenatal

testosterone

1. T in blood stream

2. Transceullular lipophilic pathway 3. Astrocyte glial cell

4. Binds with androgen receptor 5. Enters nucleus, binds with DNA,

affects transcription

Testosterone

Prenatal

testosterone

• Prenatal

testosterone



child

development?

– Difficult

to

study

in

humans

• Manipulation of hormone environment unethical!

– Natural

experiments

• Congenital Adrenal Hyperplasia (CAH)

• Genetic deficiency in the enzyme 21‐hydroxylase • Overproduction of adrenal androgens

• Female testosterone within or above the typical male range

Prenatal

testosterone

• Congenital

Adrenal

Hyperplasia

– Females typically have VIQ < PIQ

• Hampson et al., 1998; Kelso et al., 2000; Kelso et al., 1999; Resnick et al., 1986

rate of language difficulties

–rate of language difficulties

• Plante et al., 1996

• But…

– difficult to extrapolate from clinical cases to the broader

population

(3)

Cambridge

Cohort

• Cambridge

Cohort

– Simon Baron‐Cohen and colleagues

– Second trimester amniotic fluid

Inverse association

Birth

Inverse association with expressive vocab

No association with verbal IQ (or PIQ)

Mixed evidence

12- 20 weeks 2 years 6-10 years

Cambridge

Cohort

• Amniocentesis

– Limitations

1. Unrepresentative samples

2. Weak association with fetal circulatingg testosterone levels

Another

method

• Umbilical

cord

blood

– Advantage

• Easily obtained at normal delivery

Another

method

• Umbilical

cord

blood

– Limitations

• May not reflect concentrations during 1st_&₂nd_trimester

(particularly GA weeks 8‐24).

• Perhaps advantageous?

Current

Study

Current

Study

• Aim:

– To determine the association between testosterone

concentrations from umbilical cord blood and early

language development

Birth

T concentrations from cord blood

Language development to age 3 years

(4)

Current

Study

• Western

Australian

Pregnancy

Cohort

(Raine)

Study

– 2900 pregnant women recruited between 1989 and 1991

– Randomized controlled trial of ultrasonography

• Follow

‐

up

– N = 2868 at birth – Every 2 – 3 years – Retention ~ 65%

Predictor

variable

• Predictor

variable

– Umbilical

cord

testosterone

• At

birth

1989 1991

C d bl

d b i

d

828 bi h

– 1989

‐

1991

:

Cord

blood

obtained

at

828 births

– 2011:

Analyzed

for

androgens

20 years

Predictor

variable

• Biochemistry

– Step

1

• Measure total testosterone (LC/MS)

• SHBGSHBG (RIA)(RIA)

– Step

2

• Calculate ‘free testosterone’

– Free T = Total testosterone ‐SHBG

• Calculate BioT

– BioT = Free T + albumin‐bound testosterone

Predictor

variable

40 50 60 Females Males 0 10 20 30 40 0. 08 0.10 0.15 0.20 250. 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 700. 0.75 0.80 0.85 0.90 1.00 1.05 1.10 1.15 201. 1.25 1.30 1.35 1.40 1.45 1.50 1.55 1.60 651. 1.70 2.00 3.00 4.00 Fr eq u e n cy

Total testosteroneBioT concentrations (nM)

Predictor

variable

• Biochemistry

– Step

1

• Measure total testosterone (LC/MS)

• SHBG (RIA)

– Step

2

• Calculate ‘free testosterone’

– Free T = Total testosterone ‐SHBG

• Calculate BioT

– BioT = Free T + albumin‐bound testosterone – Quartiles: Quartile 1 (lowest) Quartile 4 (highest) – Separately for males and females

Outcome

variable

• Outcome

variable

– Infant

development

• Ages

1,

2 and

3 years

I f

M

i

Q

i

– Infant

Monitoring

Questionnaire

• Parent‐report

• Five domains

(5)

Outcome

variable

• Infant

Monitoring

Questionnaire

– Communication

“Does your child make sentences that are three or four words long?”

– Gross

Motor

Does your child run well, being able to stop himself without bumping into things or falling?

– Fine

Motor

Does your child hold a pencil or crayon with his fingers and thumb the way an adult does?

– Adaptive

After he watches you draw a cross (+) on paper, does your child make one like yours.

– Personal/Social

When playing with a stuffed animal or doll, does your child pretend to feed or dress it?

Outcome

variable

• Outcome

variable

– Infant

development

• Ages

1,

2 and

3 years

I f

M

i

Q

i

– Infant

Monitoring

Questionnaire

– Parent

‐

report

questionnaire

– 12

‐

,

24 ‐

,

and

36 ‐

month

questionnaires

– Clinical

cutoffs

for

each

scale

at

each

age

• Binary variable (‘Delayed’ vs ‘Not delayed’)

Statistics

Quartile 1 (Lowest)

Quartile 2 Quartile 3 Quartile 4 (highest)

Delayed % % % %

Quartile 1 (Lowest)

Quartile 2 Quartile 3 Quartile 4 (highest)

Delayed % % % %

Statistical

analyses

1. Sex

differences

in

IMQ

scores

2. Follow

‐

up

– BioT and

IMQ

scores

• Generalized Estimating Equations

– Include covariates (gestational age a birth, birthweight,

socioeconomic status)

Sex

differences

‘Communication’ was the only consistent sex-difference

Outcome

variable

• Language

delay

more

common

in

males

(6)

Males

4 5 6 5 % C I) for p air m e n t 0 1 2 3 Quartile 1 (lowest)

Quartile 2 Quartile 3 Quartile 4

(highest) O dds Rat io (9 5 language I m p Testosterone concentrations

Males

4 5 6 5 % C I) for p air m e n t 0 1 2 3 Quartile 1 (lowest)

Males

4 5 6 5 % C I) fo r p air m e n t 0 1 2 3 Quartile 1 (lowest)

Males

Females

0.8 1 1.2 1.4 % C I) fo r ir m ent 0 0.2 0.4 0.6 Quartile 1 (lowest)

(highest) O dds Rat io (9 5 % language I m pa i Testosterone concentrations

(7)

Conclusions

• Findings

– Males:



testosterone

from

cord

blood =



risk

for

language

delay

– Females:

Females:



testosterone from cord blood =

testosterone

from

cord

blood =

↓

risk

for

language

delay

– Sex

specific

effects?

• Circulatory system

• Central Nervous System as well?

Planned

studies

Happening right now

Happening

right

now

Mechanisms

• How

does

prenatal

T

influence

language?

– Cerebral

lateralization

a

l Left

Whitehouse & Bishop, Neuropsychologia, 2009

V is uos pat ia Language Right Right Left

Cerebral

lateralisation

• LI

as

a

failure

to

develop

lateralisation?

• Long history (1920s)

– Mixed evidence

– For:

•Structural: Cohen et al., 1989; Jernigan et al., 1991; Plante et al.,

1991; Gauger et al., 1997; Herbert et al., 2003; Jäncke et al., 2007)

•Functional:Tzourio et al., 1994; Chiron et al., 1999; Bernal and

Altman, 2003; Lou et al., 1984, 1990; Ors et al., 2005).

– Against:

• Shafer et al., 2000; Trauner et al., 2000; Preis et al., 1998

Samuel Orton

Cerebral

lateralisation

• Oxford

study

– Adults

with:

• SLI • ASD t Hem is phere • SLI history • Typical

– fTCD

• Word generation Lef t Right Hem is phere

Whitehouse & Bishop, Brain, 2009

Cerebral

lateralisation

• Prenatal

testosterone



cerebral

lateralization

– Long

history

(1980s)

– Geschwind

and

Galaburda

Evidence

– Evidence

• Congenital Adrenal Hyperplasia

– Handedness, dichotic listening

• Mixed at best

– Fell out of favour

(8)

Planned

Studies

1. Raine

study

follow

‐

up

– 50

low

BioT

and

50 high

BioT

(for

each

sex)

– fTCD

• Word generation (left hemisphere)

Left Right

Sex differences?

Planned

studies

2. Prenatal

investigation

of

autism

“I knew from the very first time I held him in my arms that there was something different about him.”

Genetic evidence Postnatal evidence DoHAD Prenatal

Planned

studies

• But

ASD

is

diagnosis

in

postnatal

life…

– How

do

we

study

the

prenatal

period?

1% 18.7% ASD ‘Low’ risk ‘High’ risk Ri sk of A S D

Planned

studies

Planned

studies

• PRISM

– Pregnant

women

with

an

existing

child

with

ASD

(9)

Planned

studies

2. PRISM

– Pregnant

women

with

an

existing

child

with

ASD

Follow development of child Birth

Planned

studies

N = 100 N = 100 Case families Control families

Conclusions

(10)

Key

messages

• Summary:

1. Prenatal period is an important epoch

• Testosterone (Whitehouse et al., in press, JCPP)

• Vitamin D (Whitehouse et al., 2012, Pediatrics)

2. Biology is also important…

Implications

• Once

we

identify

mechanisms,

we

can:

1. Promote the healthiest prenatal environment possible

2. Furthermore, we could:

• Identify subgroups of LI

• Increase monitoring of ‘at risk’ children. • Development of more targeted interventions

steps

• Further

examine:

Prenatal testosterone

exposure

– Human replication

– Animal models

– Randomised controlled trials

Language development Cerebral lateralisaion

Acknowledgements

Psychologists

Cheryl Dissanayake (La Trobe) Lauren Hollier (UWA) Murray Maybery (UWA)

Obstetricians

Pharmacologist

Jeff Keelan (UWA)

Paediatrician

Eugene Mattes (UWA) Michael Sawyer (Adelaide)

Obstetricians

Tony Murphy (UWA) John Newnham (UWA) Craig Pennell (UWA)

Michael Sawyer (Adelaide)

Gynaecologist

Martha Hickey (Melbourne)

Thank

you

Email:

[email protected]

Website:

http://autism.childhealthresearch.org.au

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Predictor

variable

T T T T Free T Bound T T T T T Brain tissue T T SHBG T T SHBG T T SHBG