Language Disorders in Children with congenital hypothyroidism

1. 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.

2. 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).

3. Congenital hypothyroidism (CH) is the deficiency of thyroid hormone. Which may be severe and 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) .

4. Thyroid hormone deficiency does not cause major changes in the gross anatomy of the brain, but it impairs the cytoarchitechture of the neocortex inthe cerebellum ( Glorieux et al, 1988). • Also, there are changes in the cortical patterns of lamination and axonal projection (Bargagna, 1989).

5. 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 the cerebral cortex (Noven & Arenes, 2006).

6. 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).

7. 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).

8. 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.

9. 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.

10. Also Fuggle et al (1988) reported that congenital hypothyroidism may be associated with hearing and language impairment. • The problems in receptive language, auditory processing and reading may persist in hypothyroid children, particularly if their treatment with l-thyroxin is delayed into the third week of life.

11. 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).

12. Aim Of the work • The objective of this study is to estimate the size of language disorder and detect the factors influencing language acquisition in the children with congenital hypothyrodism.

13. Subjects and Methods subject • 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.

14. 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.

15. Methods • Each child of the 3 groups was subjected to the protocol of language assessment, which applied in The Unit of Phoniatrics-El Minia University Hospitals.

16. Results

17. Age with months Non-statistical significant difference was obtained between G1 , G2 and G3 as regard the age (P<0.05).

18. Non-statistical significant difference was obtained between G1 , G2 and G3 as regard sex (P<0.05).

19. I.Q A statistical significant differences were obtained between G1 and G2 as regard the I.Q (P>0.05). A high statistical significant differences were obtained between G1 and G3 as regard the I.Q (P>0.05).

20. Mental age Age with months 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).

21. Social age Age with months 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).

22. Language age 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).

23. TSH level A statistical significant differences were obtained between G1 and G2 as regard the TSH level(P>0.05). A high statistical significant differences were obtained between G1 and G3 as regard the TSH level (P>0.05).

24. T4 level A statistical significant differences were obtained between G1 and G2 as regard the T4 level (P>0.05). A high statistical significant differences were obtained between G1 and G3 as regard the T4 level (P>0.05).

25. The audiological assessment: • Non-statistical significant difference was obtained between the two groups as regard the audiological evaluation (P. < 0.05).

26. 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).

27. Discussion • This study aimed at investigating the language developmental outcomes of the children with congenital hypothyroidism (study group) 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 abilities of their children.

28. 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 the controlled hypothyroidism and non- controlled hypothyroid functional children as regard the IQ , social and mental age.

29. 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 .

30. 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%.

31. 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.

32. 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 between the controlled hypothyroidism and non- controlled hypothyroid functional children as regard language age. These results are in agreement with those ofGlorieux et al, (1988), Fuggle et al (1988) and Rovet et al,(1992),

33. 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 after replacement therapy with levothyroxine.

34. But our result not matched toDenman (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.

35. Rovet et al., (1995) indicate that the neuropsychological functioning of children with congenital hypothyroidism (CH) is affected by factors associated with the disease and its treatment.

36. 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.

37. 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 on indices of immediate and delayed visual memory and attention. While, 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.

38. 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.

39. This result is matched to Kooistra et al (1995) showed Significant correlations between the start of therapy and both motor scores and performance IQ scores at the age of 7 years in children with severe hypothyroidism.

40. Also, Soon and Song (2001) observed that children's thyroid hormone levels at the time of testing were positively correlated with indices of memory, language, speed of processing, and fine motor performance, whereas TSH levels were negatively associ­ated with receptive language and recognition memory skills.

41. 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 with controlled hypothyroidism and normal children.

42. 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 and to provide remediation in language.

43. 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 .

44. Thank you