Endocrine Abstracts

Background and objectives: Goitre is still one of endemic health problems in Gorgan city after one decade of universal salt iodization in Iran. Hypothyroism have different complications in children that between them, developmental disorders of CNS are so important. This study proposed to determine that prevalence of thyroid function and volume disorders and its correlation with IQ in the mental retard (MR) children.

Material and methods: This cross-sectional study was carried out on 120 mental retard students of tow rehabilitation center of Gorgan city, north of Iran. We exclude the cerebral palsy and major metabolic disease suffering patients from this study. Thyroid volume was measured by an ultra-sonography (US) specialist. IQ was evaluated by standard questionnaire.

Results: Mean age of children was 11.7 years. Goitre prevalence in physical examination was 42% but it was 84% in US evaluation. Mean concentration of TSH and T4 in all cases was 3.9 and 5.7 respectively. TSH concentration had a reverse linear correlation with IQ but T4 concentration was opposite this (P<0.05). About 34 cases (28.3%) had TSH concentration upper than normal range. About 45 cases had low IQ score and 42 was moderate and 33 had high IQ score.

Conclusion: We found that serum TSH and thyroid volume have had a reverse correlation with IQ in MR children. Thyroid enlargement and hypothyroidism is more prevalent in mental retard children than others. So we should make some decisions to screen and cure thyroid disorders in this high risk population. We consider to evaluate the iodine intake status and thyroid autoimmunity in this population for future investigation.