PHYSICAL, NEUROMOTOR AND INTELLECTUAL IMPAIRMENT IN NON-CRETINOUS SCHOOLCHILDREN WITH IODINE DEFICIENCY

Thyroid status and neurologic, psychometric and auditory functions wer e evaluated in presumably normal schoolchildren aged 6 to 16 years fro m three areas of iodine deficiency in Iran. The subjects from each are a were identified as members of groups A, B or C. In group A there wer e retarded growth, high prevalence of visible goiter (93%), low T4 (39 %) and high TSH (70%). in group B 66% had a visible goiter and 7% had high serum TSH. In group C visible goiter was present in 22% of the su bjects but they had normal thyroid function. Urinary iodine excretion was low in all three groups. Head circumference was less in groups A a nd B, as compared to C. Pyramidal signs occurred in over half of the s ubjects in group A (hyperreflexia in 39% and crossed adductor reflex i n 29%). The glabellar sign was present in 50% of group A and 20% of gr oup B, Forty-four percent of the subjects in group A and 17% in group B had hearing deficits as shown by audiometry. Psychomotor examination was performed using the Bender Gestalt test, A higher number of error s was evident in groups A and B their psychomotor age was below their chronological age. The results of the Raven test showed mild impairmen t of IQ in group A, with 55% having an Ie below 91 and 15% less than 7 0. The subjects in group B had lower IQ than group C, but higher than group A, There was a negative correlation between serum TSH and free t hyroid indices and a positive correlation between TSH and the number o f pyramidal signs. This study demonstrates that mild to moderate growt h retardation and neurological, auditory and psychomotor impairments o ccur in apparently normal subjects residing in areas of iodine deficie ncy.