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Congenital Hypothyroidism

A Review of Current Diagnostic and Treatment Practices in Relation to Neuropsychologic Outcome

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Abstract

Because thyroid hormone is essential for normal brain development, children born with congenital hypothyroidism who lack thyroid hormone during a circumscribed period of early development are at risk of brain damage and mental retardation. Since the advent of newborn screening programs in the 1980s, the diagnosis and treatment of this condition are now provided in the first 2–3 weeks of birth in most regions. While this is usually sufficient to prevent mental retardation, the children so identified attain mildly reduced IQs from expectation, and may still experience subtle and specific neurocognitive deficits. Their particular deficits are related to the brief period of thyroid hormone insufficiency they undergo, especially factors reflecting the severity of hypothyroidism at the time of diagnosis, the duration of hypothyroidism in infancy, and thyroid hormones at time of testing.

In this article, we review the specific kinds of deficits demonstrated by children with congenital hypothyroidism who were diagnosed by screening and treated early, as well as the factors associated with their disease and its management that contribute to these deficits. The disease-related factors that will be reviewed will include the etiology of hypothyroidism and severity of disease at the time of diagnosis, while the treatment-related factors will include age at onset of therapy, starting and subsequent dose levels, compliance, and treatment-adequacy issues. Also examined will be the effects of hormone levels at the time of testing. In addition, the role of moderating variables such as social, genetic, and environmental influences, as well as the child’s gender, will be discussed. Furthermore, several new issues including the quality of subsequent management, ultimate outcome, and pregnancy will be additionally reviewed.

In conclusion, while outcome in congenital hypothyroidism is substantially improved by screening, affected children do still experience mild neuropsychologic deficits. To reduce the impact of persisting deficits, further research is needed to determine the optimal starting dose for the different etiologies, guidelines for subsequent management, and alternative therapies. Moreover, now that the original samples are reaching adulthood and, in females, childbearing age, further research is also needed regarding treatment during pregnancy in women with congenital hypothyroidism, as is research to determine how this population ultimately fares in adulthood.

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References

  1. LaFranchi S. Congenital hypothyroidism: etiologies, diagnosis, and management. Thyroid 1999; 9: 735–40

    Article  CAS  PubMed  Google Scholar 

  2. Van Vliet G. Neonatal hypothyroidism: treatment and outcome. Thyroid 1999; 9: 79–84

    Article  PubMed  Google Scholar 

  3. Komatsu M, Takahashi T, Takahashi K, et al. Thyroid dysgenesis caused by PAX8 mutation: the hypermutability with CpG dinucleotides at codon 31. J Pediatr 2001; 139: 596–9

    Google Scholar 

  4. Clifton-Bigh RJ, Wentworth JM, Heinz P, et al. Mutation of the gene encoding human TTF-2 associated with thyroid agenesis, cleft palate and choanal atresia. Nat Genet 1998; 19: 399–401

    Article  Google Scholar 

  5. Macchia PE, Lapi P, Krude H, et al. PAX mutations associated with congenital hypothyroidism caused by thyroid dysgenesis. Nat Genet 1998; 19: 83–6

    Article  CAS  PubMed  Google Scholar 

  6. Moreno JC, Bikker H, Kempers MJE, et al. Inactivating mutations in the gene for thyroid oxidase 2 (THOX2) and congenital hypothyroidism. N Engl J Med 2002; 347: 95–102

    Article  CAS  PubMed  Google Scholar 

  7. Calaciura F, Mendoria G, Distefano M, et al. Childhood IQ measurements in infants with transient congenital hypothyroidism. Clin Endocrinol (Oxf) 1995; 43: 473–7

    Article  CAS  Google Scholar 

  8. Brown RS, Bellisario RL, Botero D, et al. Incidence of transient congenital hypothyroidism due to maternal thyrotropin receptor-blocking antibodies in over one million babies. J Clin Endocrinol Metab 1996; 81: 1147–51

    Article  CAS  PubMed  Google Scholar 

  9. Crome L, Stern J. Pathology of mental retardation. Edinburgh: Churchill Livingstone, 1972

    Google Scholar 

  10. Brooke CGD. The consequences of congenital hypothyroidism. Clin Endocrinol (Oxf) 1995; 42: 432–8

    Google Scholar 

  11. Rovet JF. Congenital hypothyroidism: long-term outcome. Thyroid 1999; 9: 741–8

    Article  CAS  PubMed  Google Scholar 

  12. Heyerdahl S. Long term outcome in children with congenital hypothyroidism. Acta Paediatr 2001; 90: 1220–2

    Article  CAS  PubMed  Google Scholar 

  13. Hrytsiuk K, Gilbert R, Logan S, et al. Starting dose of levothyroxine for the treatment of congenital hypothyroidism: a systematic review. Arch Pediatr Adolesc Med 2002; 156: 485–91

    PubMed  Google Scholar 

  14. Dussault JH, Coulombe P, Laberge C, et al. Preliminary report on a mass screening program for neonatal hypothyroidism. J Pediatr 1975; 86: 670–4

    Article  CAS  PubMed  Google Scholar 

  15. Fisher DA, Dussault JH, Foley TP, etal. Screening for congenital hypothyroidism: results of screening one million North American infants. J Pediatr 1979; 94: 700–5

    Article  CAS  PubMed  Google Scholar 

  16. New England Congenital Hypothyroidism Collaborative. Effects of neonatal screening for hypothyroidism: prevention of mental retardation by treatment before clinical manifestations. Lancet 1981; II: 1095–8

    Google Scholar 

  17. Daliva AL, Linder B, DiMartino-Nardi J, et al. Three-year follow-up of borderline congenital hypothyroidism. J Pediatr 2000; 136: 53–6

    Article  CAS  PubMed  Google Scholar 

  18. Siklar Z, Tezer H, Dallar Y, et al. Borderline congenital hypothyroidism in the neonatal period. J Pediatr Endocrinol Metab 2002; 15: 817–21

    Article  PubMed  Google Scholar 

  19. Glorieux J, Desjardins M, Letarte J, et al. Useful parameters to predict the eventual mental outcome of hypothyroid children. Pediatr Res 1988; 24: 6–8

    Article  CAS  PubMed  Google Scholar 

  20. Rovet J, Ehrlich R, Sorbara D. Intellectual outcome in children with fetal hypothyroidism: implications for neonatal diagnosis. J Pediatr 1987; 110: 700–4

    Article  CAS  PubMed  Google Scholar 

  21. American Academy of Pediatrics, Section on Endocrinology and Committee on Genetics, and American Thyroid Association Committee on Public Health. Newborn screening for congenital hypothyroidism: recommended guidelines. Pediatrics 1993; 91: 1203–9

    Google Scholar 

  22. Fisher DA. The importance of early management in optimizing IQ in infants with congenital hypothyroidism [editorial]. J Pediatr 2000; 136: 273–4

    Article  CAS  PubMed  Google Scholar 

  23. Rovet JF, Ehrlich RM. Long-term effects of L-thyroxine therapy for congenital hypothyroidism. J Pediatr 1995; 126: 380–6

    Article  CAS  PubMed  Google Scholar 

  24. Ehrlich RM. Thyroxine dose for congenital hypothyroidism [editorial]. Clin Pediatr (Phila) 1995; 34: 521–2

    Article  CAS  Google Scholar 

  25. Dubuis JM, Gloriueux J, Richer F, et al. Outcome of severe congenital hypothyroidism: closing the developmental gap with early high dose of levothyroxine treatment. J Clin Endocrinol Metab 1996; 81: 222–7

    Article  CAS  PubMed  Google Scholar 

  26. Gunn AJ, Wake M, Cutfield WS. High and low dose initial thyroxine therapy for congenital hypothyroidism. J Paediatr Child Health 1996; 32: 242–5

    Article  CAS  PubMed  Google Scholar 

  27. Touati G, Leger J, Toublanc JE, et al. An thyroxine dosage of 8 µig/kg per day is appropriate for the initial treatment of the majority of infants with congenital hypothyroidism. Eur J Pediatr 1997; 156: 94–8

    Article  CAS  PubMed  Google Scholar 

  28. Hindmarsh PC. Optimisation of thyroxine dose in congenital hypothyroidism. Arch Dis Child 2002; 86: 73–5

    Article  CAS  PubMed  Google Scholar 

  29. Rovet JF. Neurobehavioral consequences of congenital hypothyroidism identified by newborn screening. In: Stabler B, Bercu BB, editors. Therapeutic outcome of endocrine disorders: efficacy, innovation, and quality of life. New York: Springer-Verlag, 2000: 235–54

    Chapter  Google Scholar 

  30. Leger J, Larroque B, Norton J, et al. Influence of severity of congenital hypothyroidism and adequacy of treatment on school achievement in young adolescents: a population-based cohort study. Acta Paediatr 2001; 90: 1249–56

    Article  CAS  PubMed  Google Scholar 

  31. Bunevicius R, Kazanavicius G, Zalinkevicius R, et al. Effects of thyroxine as compared with thyroxine plus triiodothyronine in patients with hypothyroidism. N Engl J Med 1999; 340: 424–9

    Article  CAS  PubMed  Google Scholar 

  32. Working group on congenital hypothyroidism of the European Society for Paediatric Endocrinology. Guidelines for neonatal screening programmes for congenital hypothyroidism. Eur J Pediatr 1993; 152: 974–5

    Article  Google Scholar 

  33. Hodges S, O’Malley BP, Northover BN, et al. Reappraisal of thyroxine treatment in primary hypothyroidism. Arch Dis Child 1990; 65: 1129–32

    Article  CAS  PubMed  Google Scholar 

  34. Hanukoglu A, Perlman K, Shamis I, et al. Relationship of etiology to treatment in congenital hypothyroidism. J Clin Endocrinol Metab 2001; 86: 186–91

    Article  CAS  PubMed  Google Scholar 

  35. Heyerdahl S, Kase BF. Significance of elevated serum thyrotropin during treatment of congenital hypothyroidism. Acta Paediatr 1995; 84: 634–8

    Article  CAS  PubMed  Google Scholar 

  36. Schultz RM, Glassman MS, MacGillivray MH. Elevated threshold for thyrotropin suppression in congenital hypothyroidism. Am J Dis Child 1980; 134: 19–20

    CAS  PubMed  Google Scholar 

  37. Fisher DA, Schoen EJ, LaFranchi S, et al. The hypothalamic-pituitary-thyroid negative feedback control axis in children with treated congenital hypothyroidism. J Clin Endocrinol Metab 2000; 85: 2722–7

    Article  CAS  PubMed  Google Scholar 

  38. Song S, Daneman D, Rovet J. The influence of etiology and treatment factors on intellectual outcome in congenital hypothyroidism. J Dev Behav Pediatr 2001; 22: 376–84

    Article  CAS  PubMed  Google Scholar 

  39. Davy T, Daneman D, Walfish PG, et al. Congenital hypothyroidism: the effect of stopping treatment at 3 years. Am J Dis Child 1985; 139: 1028–30

    CAS  PubMed  Google Scholar 

  40. Bernal J, Nunez J. Thyroid hormones and brain development. Eur J Endocr 1995; 133: 390–8

    Article  CAS  Google Scholar 

  41. Thompson CC, Potter GB. Thyroid hormone action in neural development. Cereb Cortex 2000; 10: 939–45

    Article  CAS  PubMed  Google Scholar 

  42. Shapiro S. Metabolic and maturational effects of thyroxine in the infant rat. Endocrinology 1966; 78: 527–32

    Article  Google Scholar 

  43. Potter B, Mano M, Belling G, et al. Retarded fetal brain development resulting from severe dietary iodine deficiency in sheep. Neuropathol Appl Neurobiol 1982; 8: 303–13

    Article  CAS  PubMed  Google Scholar 

  44. Legrand J. Effects of thyroid hormones on central nervous system development. In: Yanat J, editor. Neurobehavioral teratology. Amsterdam: Elsevier, 1984: 331–63

    Google Scholar 

  45. Rosman N, Malone M, Helfenstein M, et al. The effect of thyroid deficiency on myelination of the brain. Neurology 1972; 22: 99–106

    Article  CAS  PubMed  Google Scholar 

  46. Iniguez M, De Lecea L, Guadano-Ferraz A, et al. Cell-specific effects of thyroid hormone on RC3/neurogranin expression in rat brain. Endocrinology 1996; 137: 1032–41

    Article  CAS  PubMed  Google Scholar 

  47. Brent GA. The molecular basis of thyroid hormone action. N Engl J Med 1994; 221: 847–53

    Google Scholar 

  48. Nunez J. Differential expression of microtubule components during brain development. Dev Neurosci 1986; 8: 125–41

    Article  CAS  PubMed  Google Scholar 

  49. Fellous A, Lennon A, Francon J, et al. Thyroid hormones and neurotubule assembly in vitro during brain development. Eur J Biochem 1979; 101: 365–76

    Article  CAS  PubMed  Google Scholar 

  50. Farsetti A, Mitsuhashi T, Desvergen B, et al. Molecular basis of thyroid hormone regulation of myelin basic protein gene expression in rodent brain. J Biol Chem 1991; 166: 23226–32

    Google Scholar 

  51. Dowling ALS, Zoeller RT. Thyroid hormone of maternal origin regulates the expression of RC3/neurogranin mRNA in the fetal rat brain. Mol Brain Res 2000; 82: 126–32

    Article  CAS  PubMed  Google Scholar 

  52. Bradley D, Young W, Weinberger C. Differential expression of α and β thyroid hormone receptor genes in rat brain and pituitary. Proc Natl Acad Sci USA 1989; 86: 7250–4

    Article  CAS  PubMed  Google Scholar 

  53. Morreale de Escobar G, Obregon MJ, Escobar del Rey F. Is neuropsychological development related to maternal hypothyroidism or to maternal hypothyroxinemia. J Clin Endocrinol Metab 2000; 85: 3975–87

    Article  CAS  PubMed  Google Scholar 

  54. Bradley DJ, Towle HC, Young WS. Spatial and temporal expression of α- and β-thyroid hormone receptor mRNAs, including the β2-subtype, in the developing mammalian nervous system. J Neurosci 1992; 12: 2288–302

    CAS  PubMed  Google Scholar 

  55. Francois M, Bonfils P, Leger J, et al. Role of congenital hypothyroidism in hearing loss in children. J Pediatr 1994; 123: 444–6

    Google Scholar 

  56. Rovet J, Walker W, Bliss B, et al. Long-term sequelae of hearing impairment in congenital hypothyroidism. J Pediatr 1996; 128: 776–83

    Article  CAS  PubMed  Google Scholar 

  57. Rovet J, Mirabella G, Westall C, et al. Visual processing deficits associated with pre- and perinatal thyroid hormone deficiencies. 73rd Annual Meeting of the American Thyroid Association; 2001 Nov 7–10; Washington, DC, 95

  58. Lauder JM, Krebs H. Do neurotransmitters, neurohumors, and hormones specify critical periods. In: Greenough WT, Juraska JM, editors. Developmental neurophysiology. New York: Academic Press, 1986: 120–74

    Google Scholar 

  59. Virgili M, Saverino O, Vaccari M, et al. Temporal, regional and cellular selectivity of neonatal alteration of the thyroid state on neurochemical maturation in the rat. Exp Brain Res 1991; 83: 556–61

    Article  Google Scholar 

  60. Puymirat J, Luo M, Dussault HL. Immunocytochemical localization of thyroid hormone nuclear receptors in cultured hypothalamic dopaminergic neurons. Neuroscience 1989; 30: 443–9

    Article  CAS  PubMed  Google Scholar 

  61. Rovet JF. Behavioral and cognitive abnormalities associated with congenital hypothyroidism. In: Hauser P, Rovet J, editors. Thyroid disorders in infancy and childhood. Washington, DC: American Psychiatric Press, 1998: 85–126

    Google Scholar 

  62. Simons WF, Fuggle PW, Grant DB, et al. Educational progress, behaviour, and motor skills at age 10 years in early-treated congenital hypothyroidism. Arch Dis Child 1997; 77: 219–22

    Article  CAS  PubMed  Google Scholar 

  63. Gruters A, Jenner A, Krude H. Long-term consequences of congenital hypothyroidism in the era of screening programmes. Best Pract Res Clin Endocrinol Metab 2002; 16: 369–82

    Article  PubMed  Google Scholar 

  64. Illick A, Larson A. Phychological development at 7 years of children with congenital hypothyroidism. Acta Paediatr Scand 1992; 80: 199–204

    Article  Google Scholar 

  65. Illig R, Largo RH, Qin Q, et al. Mental development in congenital hypothyroidism after neonatal screening. Arch Dis Child 1987; 62: 1050–5

    Article  CAS  PubMed  Google Scholar 

  66. New England Congenital Hypothyroidism Collaborative. Elementary school performance of children with congenital hypothyroidism. J Pediatr 1990; 116: 27–32

    Article  Google Scholar 

  67. Derksen-Lubsen G, Verkerk PH. Neuropsychologic development in early-treated congenital hypothyroidism: analysis of literature data. Pediatr Res 1996; 39: 561–6

    Article  CAS  PubMed  Google Scholar 

  68. Rovet JF. Long-term neuropsychological sequelae of early-treated congenital hypothyroidism: effects in adolescence. Acta Paediatr Suppl 1999; 88(432): 88–95

    Article  CAS  PubMed  Google Scholar 

  69. Connelly JF, Rickards AL, Coakley JC, et al. Newborn screening for congenital hypothyroidism, Victoria, Australia, 1977–1997 (part II): treatment, progress, and outcome. J Pediatr Endocrinol Metab 2001; 14: 1611–34

    CAS  PubMed  Google Scholar 

  70. Kooistra L, Laane C, Vulsma T, et al. Motor and cognitive development in children with congenital hypothyroidism: a long-term evaluation of the effects of neonatal treatment. J Pediatr 1994; 124: 903–9

    Article  CAS  PubMed  Google Scholar 

  71. Fuggle PW, Grant DB, Smith I, et al. Intelligence motor skills and behaviour at 5 years in early-treated congenital hypothyroidism. Eur J Pediatr 1991; 150: 570–4

    Article  CAS  PubMed  Google Scholar 

  72. Gottschalk B, Richman R, Lewandowski L. Subtle speech and motor deficits of children with congenital hypothyroidism treated early. Dev Med Child Neurol 1994; 36: 216–20

    Article  CAS  PubMed  Google Scholar 

  73. Rovet J, Ehrlich R, Sorbara D. Neurodevelopment in infants and preschool children with congenital hypothyroidism: etiological and treatment factors affecting outcome. J Pediatr Psychol 1992; 17: 187–213

    Article  CAS  PubMed  Google Scholar 

  74. Kooistra L, van der Meere JJ, Vulsma T, et al. Sustained attention problems in children with early treated congenital hypothyroidism. Acta Paediatr 1996; 85: 425–9

    Article  CAS  PubMed  Google Scholar 

  75. Rovet J, Alvarez M. Thyroid hormone and attention in children with congenital hypothyroidism. J Pediatr Endocrinol Metab 1996; 9: 63–6

    Article  CAS  PubMed  Google Scholar 

  76. Rovet JF, Ehrlich R. The psychoeducational characteristics of children with early-treated congenital hypothyroidism. Pediatrics 2000; 105: 515–22

    Article  CAS  PubMed  Google Scholar 

  77. Bargagna S, Dinetti D, Pinchera A, et al. School attainments in children with congenital hypothyroidism detected neonatal screening and treated early in life. Eur J Endocrinol 1999; 140: 407–13

    Article  CAS  PubMed  Google Scholar 

  78. Glorieux J, Dussault J, Van Vliet F. Intellectual development at age 12 years in children with congenital hypothyroidism diagnosed by neonatal screening. J Pediatr 1992; 121: 581–4

    Article  CAS  PubMed  Google Scholar 

  79. Rochiccioli P, Roge B, Dechaux E, et al. School achievement in children with hypothyroidism detected at birth and search for predictive factors. Horm Res 1992; 38: 236–40

    Article  CAS  PubMed  Google Scholar 

  80. Salerno M, Militerni R, Bravaccio C, et al. Effect of different starting doses of levothyroxine on growth and intellectual outcome at four years of age in congenital hypothyroidism. Thyroid 2002; 12: 45–52

    Article  CAS  PubMed  Google Scholar 

  81. Kooistra L, Stermdink N, van der Meere J, et al. Behavioural correlates of early-treated congenital hypothyroidism. Acta Paediatr 2001; 90: 1141–6

    Article  CAS  PubMed  Google Scholar 

  82. Bargagna S, Canepa G, Costagli C, et al. Neuropsychological follow-up in early-treated congenital hypothyroidism: a problem-oriented approach. Thyroid 2000; 10: 243–9

    Article  CAS  PubMed  Google Scholar 

  83. Tillotson SL, Fuggle PW, Smith I, et al. Relation between biochemical severity and intelligence in early treated congenital hypothyroidism: a threshold effect. BMJ 1994; 309: 440–5

    Article  CAS  PubMed  Google Scholar 

  84. New England Congenital Hypothyroidism Collaborative. Correlation of cognitive test scores and adequacy of treatment in adolescents with congenital hypothyroidism. J Pediatr 1994; 124: 383–7

    Article  Google Scholar 

  85. Rovet J. Congenital hypothyroidism: psychometric outcome. 83rd Annual Meeting of the Endocrine Society; 2001 Jun 20–23; Denver (CO), 38

  86. Salerno M, Militerni R, Di Maio S, et al. Intellectual outcome at 12 years of age in congenital hypothyroidism. Eur J Endocrinol 1999; 141: 105–10

    Article  CAS  PubMed  Google Scholar 

  87. Bongers-Schokking JJ, Koot HM, Wiersma D, et al. Influence of timing and dose of thyroid hormone replacement on development in infants with congenital hypothyroidism. J Pediatr 2000; 136: 292–7

    Article  CAS  PubMed  Google Scholar 

  88. Heyerdahl S, Kase FB, Lie SO. Intellectual development in children with congenital hypothyroidism in relation to recommended thyroxine treatment. J Pediatr 1991; 118: 850–7

    Article  CAS  PubMed  Google Scholar 

  89. Rovet JF, Hepworth SL. Dissociating attention deficits in children with ADHD and congenital hypothyroidism using multiple CPTs. J Child Psychol Psychiatry 2001; 42: 1049–56

    Article  CAS  PubMed  Google Scholar 

  90. Chiovato L, Bargagna S. Congenital hypothyroidism: treat children but don’t forget their parents [commentary]. Eur J Endocrinol 1999; 14: 101–4

    Article  Google Scholar 

  91. Burrow G, Fisher D, Larsen PR. Maternal and fetal thyroid function. N Engl J Med 1994; 331: 1072–8

    Article  CAS  PubMed  Google Scholar 

  92. Calvo RM, Jauniaux E, Glubis B, et al. Fetal tissues are exposed to biologically relevant free thyroxine concentrations during early phases of development. J Clin Endocrinol Metab 2002; 87: 1768–77

    Article  CAS  PubMed  Google Scholar 

  93. Man EB, Brown JF, Serunian SA. Maternal hypothyroxinemia: psychoneurological deficits of progeny. Ann Clin Lab Sci 1991; 21: 227–39

    CAS  PubMed  Google Scholar 

  94. Pop VJ, Kuijpens JL, van Baar AL, et al. Low maternal free thyroxine concentrations during early pregnancy are associated with impaired psychomotor development in infancy. Clin Endocrinol 1999; 50: 149–55

    Article  CAS  Google Scholar 

  95. Haddow JE, Palomaki GE, Allen WC, et al. Maternal thyroid deficiency during pregnancy and subsequent neuropsychological development of the child. N Engl J Med 1999; 341: 549–55

    Article  CAS  PubMed  Google Scholar 

  96. Glinoer D. Potential repercussions for the progeny of maternal hypothyroidism during pregnancy. Thyroid 2002; 10: 59–62

    Article  Google Scholar 

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Acknowledgements

The work described in this paper was supported by grants from the Canadian Institutes of Health Research, the Ontario Mental Health Foundation, the Ontario Ministry of Health, and the Ontario Ministry of Community and Social Services.

The authors have provided no information on conflicts of interest directly relevant to the content of this review.

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Rovet, J., Daneman, D. Congenital Hypothyroidism. Pediatr-Drugs 5, 141–149 (2003). https://doi.org/10.2165/00128072-200305030-00001

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