Background:Only few studies concerning thyroid status and intellectual evaluation in iron deficiency
anemia, which is frequently seen in primary school children in Egypt. Aim:The present study was
planned to investigate the effect of iron deficiency anemia on the thyroid functions and intellectual
activity of young children in a primary school. Settings and Design:Cross-sectional controlled study.
Patients and Methods:This study was carried out on 60 primary school children aged 6-12 year with
iron deficiency anemia (Group 1) and 20 children as control (Group 2). Complete blood count, iron,
total iron binding capacityferritin, thyroid stimulating hormone (TSH), thyroxine (T4), triiodothyronine
(T3), free thyroid hormones (FT4 and FT3), and intelligence quotient (IQ) were determined in all
the children included in the study. Results:TT3 and TT4 values were statistically lower while TSH
is significantly higher in the study group as compared to control (P< 0.001 for each). Patients with
hemoglobin (HB) level < 10 > 7 g/dl had significantly lower levels of serum FT3 and FT4 (P< 0.01 for
both) and significantly higher levels of serum TSH (P< 0.05) as compared to patients with HB level
<7 g/dl.Serum ferritin was correlated negatively with TSH levels (r =−0.76, P< 0.001) while positively
with TT4 (r =0.69, P< 0.001) and TT3 (r =0.84, P< 0.001) levels. A significant positive correlation
was found between serum level of TT3 and transferrin saturation% (r =0.78, P< 0.001). Total, as well
as performance IQ were significantly lower in patients than controls with P<0.05 for each. Significant
positive correlations were observed between both total and performance IQ and thyroid hormone levels
and iron status parameters. Conclusion:Egyptian primary school children with iron deficiency anemia
especially severe type are liable to develop subclinical hypothyroidism and intellectual dysfunction. A
randomized, double-blind, controlled study is needed to address the question of whether subclinical
hypothyroidism associated with iron deficiency anemia should be treated with oral iron only or iron
and levothyroxine combination aiming to prevent the combined effects of both conditions on cognitive
function of the brain. Moreover, more comprehensive studies are needed to elucidate if the effect of
iron deficiency anemia on thyroid status is reversible or not