The Relationship between Thyroid Hormone Levels and Body Iron Status in Iranian Hypothyroidism Patients

Backgrounds and Aims: Thyroid hormones have a crucial physiological role to maintain balance of metabolism of body. Thyroid hormones have an important role in metabolism and proliferation of blood cells. Thyroid gland also has a vital influence on erythropoiesis by induction of erythropoietin secretion and proliferation of erythroid progenitors. In the present study, it was tried to evaluate the effect of hypothyroidism on hematological parameters and also body iron store. Materials and Methods: The research population consisted of 90 subjects divided into two groups: 45 people with hypothyroidism and 45 age-matched healthy individuals. This study checked the amounts of total triiodothyronine (T3), total thyroxine (T4), thyroid stimulating hormone (TSH), and some iron status and hematological parameters. Results: The mean TSH levels were significantly increased in hypothyroid patients compared to control group. On the other hand, the levels of T4 and total iron binding capacity, serum iron, ferritin, Hemoglobin, and Hematocrit were significantly lower in hypothyroid patients compared to control group (p < 0.05). However, there was no significant difference in the mean of T3 between hypothyroidism and control. Conclusion: Our data suggest that alterations in thyroid status change serum iron metabolism and hematological index. Hypothyroidism is often associated with anemia,depleted body iron store. As there is no significant clinical manifestation of hypothyroidism at earlier stages with anemia, it is advisable to routinely investigate it for early detection allowing its early management.