A comparative study of serum ferritin and thyroid stimulating hormone (TSH) levels in hypothyroid and euthyroid subjects

Thyroid hormones synthesized and released by the thyroid gland, have a vital role in regulating the metabolism of body. Synthesis of these thyroid hormones requires an iron containing enzyme Thyroid Peroxidase (TPO). Thus, iron inadequacy can affect the proper functioning of the TPO enzyme that further affect the thyroid hormone production. Serum ferritin, an index of iron store is present in almost all cells; however, it has been reported that an alteration in ferritin levels occurs in patients with thyroid disease. This study was conducted to determine serum ferritin and Thyroid Stimulating Hormone (TSH) levels in hypothyroid and euthyroid subjects and to compare the same.The retrospective study was carried out in Amrita Institute of Medical Sciences (AIMS), Kochi, which included 30 hypothyroid subjects as cases and 30 age and gender matched healthy controls. TSH, Thyroxine (T4) and serum ferritin levels of the study groups were collected and recorded.The mean TSH of hypothyroid patients was found to be higher (16.12±17.00) than that of euthyroid group (2.35± 1.08) whereas the mean value of T4 (1.01± 0.25) and ferritin (43.80 ± 75.44) were found to be reduced in patients with hypothyroidism compared to normal subjects. All the parameters were statistically significant with p value <0.05.The present study showed that hypothyroid subjects had significantly lower serum ferritin concentration than euthyroid subjects. Thus, serum ferritin measurement could be useful for the evaluation of thyroid diseases.