Language Disorders in
Children with congenital
hypothyroidism
Abd El Baky, A,A,
Mammdoh, HM.,
Zaky EA,
Abd El Wahab, MM,
Unit of Phoniatrics, Department of
Otolaryngology, Minia University.

The thyroid hormones are a major physiological regulator
of the brain development. Cell differentiation, migration
and gene expression are altered as a consequence of the
thyroid hormone deficiency or excess.

Thyroid hormone deficiency when established during the
critical
period
of
neuronal
differentiation
produces
permanent and severe alteration in the anatomy and
function of the nervous system (cretinism) (Bernal &
Nunez, 1995).
Congenital
thyroid
hypothyroidism
hormone.
(CH)
is
may
be
Which
the
deficiency
severe
and
of
its
symptoms develop in early weeks of life, in others,
lower degree of deficiency occurs, and manifestations
may be delayed for months (Dessault & Walker, 1993).

The
prevalence
of
congenital
hypothyroidism
is
1/40.000 infants worldwide .

Congenital hypothyroidism is twice as common in girls
as in boys (Delange, 1989) .

Thyroid hormone deficiency does not cause major
changes in the gross anatomy of the brain, but it
impairs the cytoarchitechture of the neocortex in the
cerebellum ( Glorieux et al, 1988).

Also, there are changes in the cortical patterns of
lamination and axonal projection (Bargagna, 1989).

Several steps of the brain development seem
to be slow down by the deficiency of thyroid
hormones whereas glial cell formation (gliosis)
and the neuronal cell death are increased.

T3 regulates the level of neurotrophine to
promote
the
development
of
cortex (Noven & Arenes, 2006).
the
cerebral

Magnetic
resonance
imaging
was
reported that most patients with CH
had mild cerebral cortical atrophy in
the frontal and parietal lobes and
identified a delay in myelination in
patients
with
untreated
congenital
hypothyroidism (Alves et al., 2004).

The neonatal screening programs and early
treatment
of
CH
has
been
effective
in
preventing the serious brain damage and
mental retardation; it is still controversial
whether
these
patients
achieve
normal
cognitive skills and language development or
not (Heyerdal et al, 1991).

Also, with early recognition and treatment of CH,
these children are slower in development than the
normal children. they concluded that congenital
hypothyroidism
affect
the
brain
development
before birth. Some of these effects last after birth
even if the replacement therapy is given regularly
since birth.

Glorieux
et
al,
(1988)
studied
the
mental
development of the hypothyroid infants and
they
found that there was no difference between the
global quotient in the 12 months. But at age of 18
months and 36 months, the hypothyroid group had
scientifically lower mean global quotient than the
control group. This was mainly in the performance
as well as the in hearing and language aquestion.

Also
Fuggle
et
al
(1988)
reported
that
congenital hypothyroidism may be associated
with hearing and language impairment.

The problems in receptive language, auditory
processing
hypothyroid
and
reading
children,
may
persist
particularly
if
in
their
treatment with l-thyroxin is delayed into the
third week of life.

On psychometric tests, the hypothyroid
group
was
observed
to
perform
scientifically poorer than the normal child
at 3 years of age but seemed to catch up
by
age
5
and
did
not
differ
on
an
expressive language test given at ago of 7
years (Rovet et al,1992).
Aim Of the work

The
objective
of
this
study
is
to
estimate the size of language disorder
and
detect
the
factors
language acquisition
influencing
in the children
with congenital hypothyrodism.
subject
Subjects and Methods

This study included 60 children.

The( study group) included 40 children who complained from
congenital hypothyrodism. This group were collected from el
Minia Insurance Hospital –Pediatric unit. The range of age of
this group from 3 to 8 years.

The results from the study group were compared to another
group (control group), which included 20 normal children . The
range of age of this group from 3 to 8 years Children of both
groups were matched in the age and sex.

G1:
the
children
with
congenital
hypothyroidism with controlled level T3 and
TSH .

G2:
the
children
with
congenital
hypothyroidism with uncontrolled level T3 and
TSH.

G3: the children with normal thyroid function.
Methods

Each
child
of
the
3
groups
was
subjected to the protocol of language
assessment, which applied in The Unit
of
Phoniatrics-El
Hospitals.
Minia
University
Results
100
90
80
70
Age with
months
70
68
71
60
50
40
30
20
10
G1
G2
G3
Non-statistical significant difference was
obtained between G1 , G2 and G3 as
regard the age (P<0.05).
20
18
16
14
12
10
8
6
4
2
0
11
14
9
13
8
m ale
fem ale
5
G1
G2
G3
Non-statistical significant difference was obtained
between G1 , G2 and G3 as regard sex (P<0.05).
I.Q
100
90
82
80
72
65
70
60
50
G1
G2
G3
A statistical significant differences were obtained between
G1 and G2 as regard the I.Q (P>0.05).
A
high
statistical
significant
differences
were
between G1 and G3 as regard the I.Q (P>0.05).
obtained
Mental age
100
90
80
Age with
months
70
75
62
60
43
50
40
30
20
G1
G2
G3
A statistical significant differences were obtained between G1
and G2 as regard the mental age (P>0.05).
A
high
statistical
significant
differences
were
obtained
between G1 and G3 as regard the mental age (P>0.05).
Social age
100
90
80
70
Age with
months
60
70
58
50
38
40
30
20
G1
G2
G3
A statistical significant differences were obtained between G1
and G2 as regard the social age (P>0.05).
A high statistical significant differences were obtained
between G1 and G3 as regard the social age (P>0.05).
Language age
80
70
60
50
57
43
40
23
30
20
10
G1
G2
G3
A statistical significant differences were obtained between G1
and G2 as regard the language age (P>0.05).
A
high
statistical
significant
differences
were
obtained
between G1 and G3 as regard the language age(P>0.05).
TSH level
19
17
15
13
11
9
7
5
3
1
14.3
1.6
G1
G2
0.6
G3
A statistical significant differences were obtained between G1
and G2 as regard the TSH level(P>0.05).
A
high
statistical
significant
differences
were
between G1 and G3 as regard the TSH level (P>0.05).
obtained
T4 level
5
4
3
2
1.2
1
1.8
0.6
0
G1
G2
G3
A statistical significant differences were obtained between G1
and G2 as regard the T4 level (P>0.05).
A
high
statistical
significant
differences
were
between G1 and G3 as regard the T4 level (P>0.05).
obtained
The audiological assessment:

Non-statistical significant difference was obtained
between the two groups as regard the audiological
evaluation (P. < 0.05).
II: Correlations:

A high positive significant correlation was obtained
between the language , mental, social age and IQ in
correlation with the level of T4 in G1 and G2 (r=0.76).

A high negative significant correlation was obtained
between the language , mental, social age and IQ in
correlation with the level of TSH in G1 and G2 (r=-0.87).
Discussion

This
study
aimed
developmental
congenital
at
investigating
outcomes
of
hypothyroidism
the
(study
the
language
children
group)
with
in
comparison to the children who with normal thyroid
functional
(control
group).
The
two
groups
were
matched as possible in their sociodemographic data
(age and sex) in order to show the effect of the
hypothyroidism
in
the
language
children.
abilities
of
their

In
this study, there was significant difference
between the hypothyroid and normal thyroid
functional children as regard the IQ , mental and
social age. Moreover , There was high significant
difference
between
hypothyroidism
the
and
controlled
non-
controlled
hypothyroid functional children as regard the IQ
, social and mental age.

This result matched to
Glorieux et al, (1988) who
found that, the hypothyroid group had scientifically
lower mean global quotient than the control group.

They
said
that
their
results
may
represent
the
manifestations of brain damage occurs even with early
detection
and
treatment
of
hypothyroidism.
Also,
Koibuchi and Chin, ( 2000) found that the children with
severe CH, had mean IQ scores 10 to 22 points below
that of their siblings .

Also, Nacfau et al (2005) found that the CH children
who were being treated for hypothyroidism starting
before the age of 2 years. Their IQ scores lay within the
normal range ( 71- 122; mean 92.4), but 77% showed
at least one sign if impaired brain function. Clumsiness
was found
in
33%, behaviour disorders
in 23%,
language disorders in 20%, learning disorders in 26%,
squint in 53%, nystagmus in 10%, and minor motor
disorders in 50%.
In the other hand, Heyerdal et al, (1991) found that
even
with
early
recognition
and
treatment
of
congenital hypothyroidism, these children are slower
in
development
than
the
normal
children.
they
concluded that congenital hypothyroidism affect the
brain development before birth. Some of these effects
last after birth even if the replacement therapy is
given regularly since birth.

The results obtained from the Arabic language test
revealed
a
significant
difference
between
the
hypothyroidism and normal thyroid functional children
as regard the language age. Moreover , There was high
significant
difference
hypothyroidism
between
the
controlled
and non- controlled
hypothyroid
functional children as regard language age. These
results are in agreement with those of Glorieux et al,
(1988) , Fuggle et al (1988) and Rovet et al,(1992),

Miller et al ( 2002) revealed that the treated
hypothyroid group had significant increased
verbal memory retrieval. Results suggest that
specific memory retrieval deficits associated
with
hypothyroidism
can
resolve
replacement therapy with levothyroxine.
after

But our result not matched to Denman (1984) who
found that the CH group did not differ from control
children
on
tests
of
phonological
processing
(WJRMT Word Attack), writing (test of written
language ( TOWL), or spelling ( WRAT_R spelling).
The
results
of
the
supplementary
tests
also
indicated no difference in language and memory
tasks.

Rovet et al., (1995) indicate that the
neuropsychological
children
with
functioning
of
congenital
hypothyroidism (CH) is affected by
factors associated with the disease
and its treatment.

Their nonverbal or visuospatial intellectual abilities
were sensitive to the etiology of hypothyroidism,
whereas several aspects of memory were sensitive
to the timing of thyrotropin (TSH) normalization.
With regard to etiology, children with athyreosis
scored significantly below the other groups on
indices of nonverbal intelligence and arithmetic
achievement.

Cohen (1997) concluded that the important of the age at
normalization
of
TSH
affected
selective
aspects
of
memory and attention functioning. Specifically, children
with CH who normalized by I to 2 months of age, scored
higher
than
those
normalizing
later
immediate and delayed visual memory
While,
on
indices
of
and attention.
children who normalized by 3 months of age
performed better than those normalizing past this age on
indices of global memory, visual memory and learning.

The study revealed that, A high positive significant
correlation was obtained between the language ,
mental, social age and IQ in correlation with the level
of T4 in the study group, Also, A high negative
significant correlation was obtained between the
language , mental, social age and IQ in correlation
with the level of TSH in the study group.

This result is matched to Kooistra
(1995)
showed
Significant
et al
correlations
between the start of therapy and both motor
scores and performance IQ scores at the age
of
7
years
hypothyroidism.
in
children
with
severe

Also, Soon and Song (2001) observed that children's
thyroid hormone levels at the time of testing were
positively
correlated
language,
speed
of
with
indices
processing,
and
of
memory,
fine
motor
performance, whereas TSH levels were negatively
associated with receptive language and recognition
memory skills.
Conclusion& Recommendation

There is evident that the children with congenital
hypothyroidism show poorer language development
in comparison to normal children, moreover the
children with uncontrolled congenital hypothyroidism
show worsen in language, mental, social age and IQ
in
comparison
to
that
children
hypothyroidism and normal children.
with
controlled

The need for diagnosis and treatment of children
with congenital hypothyroidism as soon after birth as
possible, preferably no later than the second week of
life .it is also important to screen hypothyroid
children
for
hearing
problems
remediation in language.
and
to
provide

The present study provide several challenges for the
behavioral pediatrician who may have children with
congenital hypothyroidism in his or her practice. It is
important to monitor these children frequently and
closely to ensure thyroid hormone levels maintained .