Relation between Thyroid Function and Iron Deficiency Anemia in Primary School-Age Children: A Controlled Cross-Sectional Study

Abstract

Background: Iron deficiency anemia [IDA] is a very common medical condition affecting primary school-age children, with several unfavorable consequences. There are some reports pointing to a possible effect of IDA on thyroid gland function.Aim of the work: To assess thyroid function in primary school age children in Damietta Governorate, Egypt with iron deficiency anemia and to investigate potential related risk factors.Patients and Methods: A controlled cross-sectional study included 100 primary school age children [age: 6-12 years]; 50 children with iron deficiency anemia [case group], and 50 healthy age- and sex-matched children [control group]. Complete blood count, serum iron, serum ferritin and thyroid hormone profile [thyroid stimulating hormone [TSH], free triiodothyronine [FT3] and free thyroxine [FT4] were analyzed for all children.Results: In the case group, compared to the control group, there was a significantly higher TSH level [2.77±1.30 vs. 2.10±1.11; P=0.006] and lower FT3 [3.22±0.82 vs. 3.61±0.69; P=0.011]. The frequency of hypothyroid status [both overt and subclinical] was elevated in the case group [24% vs. 6%; P=0.02]. There was a significant negative correlation between TSH with both serum iron [P=0.019] and ferritin [P=0.009].Conclusion: Iron deficiency anemia, especially when serum ferritin and iron are very low, in primary school children is associated with liability to get subclinical hypothyroidism.