Neonatal Thyroid Screening: Now We are Nine
Neonatal thyroid screening was begun in the hope that the resulting early treatment of infantile hypothyroidism would prevent the brain damage seen in patients treated only after a clinical diagnosis. We reported in 1979 at the Quebec meeting that the mean IQ of such children reported in the literature was under 80.1 In addition, it was noted that Von Harnack, Zabransky, MacFaul, and (later) Wolter all reported that even those patients with normal IQs defined as above 85 or 90 were unable to progress normally in regular school classes because of specific learning disabilities, attention deficits, neurologic problems etc.2,3,45 These latter reports lacked concurrent controls and we were dubious of their conclusions. For instance, if we separate MacFaul’s patients into those with IQs equal to or greater than 95 and those with IQs below 95, all but 2 of the patients with learning difficulties or neurologic problems fall in the latter group and the mean IQ of patients with learning difficulties is significantly lower than that of the remainder of the patients. Ninety-five is one standard deviation below the mean WISC-R IQ for most groups of normal children reported in recent years. Nonetheless, if these problems were real, we hoped that early treatment might also prevent them. How have our hopes been fulfilled over these years? All studies are unanimous in declaring that brain damage as measured by IQ scores has largely been prevented. There is argument only as to the degree of success obtained by different groups. Today, we would like to review briefly data on IQs in our cohort and to present new data on school progress of the patients.
KeywordsDown Syndrome Williams Syndrome Brain Damage Motor Speed Congenital Hypothyroidism
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