Diagnostic Role of Serum Ferritin in Patients with Hypothyroidism and Its Association with Thyroid Hormone Levels

Introduction: Thyroid diseases are common worldwide and its prevalence in India is about 42 million. It is more common among women than in men, and also it increases with age. Among the thyroid diseases, Hypothyroidism is a multiorgan disorder that occurs due to decrease in thyroid hormone synthesis; which is associated with low circulating levels of thyroid hormones. Iron plays an important role in thyroid hormone synthesis along with other minerals. Ferritin, is an important indicator of body iron stores, and its level is altered in Hypothyroidism. Various studies reveal that most of the hypothyroid individuals do suffer from associated anaemia due to iron deficiency. Iron deficiency can be detected earlier using serum Ferritin, since it out-performs in its sensitivity & specificity than many other iron deficiency markers thereby preventing cognitive ailments. Aim: This study was conducted to assess the diagnostic role of serum Ferritin in Hypothyroid individuals and to find out its association with Thyroid hormone levels. Materials and Methods: This cross-sectional study included 100 subjects (50 subjects of Hypothyroids as cases and 50 subjects of Normothyroids as controls) with age group 20-50 years of both genders. Blood samples were collected under strict aseptic precautions, and serum Total T3, T4, TSH & serum Ferritin levels were assayed. Data was analysed statistically using suitable SPSS statistical package (version 21.0). Results: There was a statistically significant decrease in serum Ferritin levels in hypothyroid individuals (40.6µg/l), when compared to Normothyroid individuals (82.9µg/l) with female preponderance. Also, there was a statistically significant positive correlation between serum Ferritin and Thyroid hormone levels (Total T4) in hypothyroid individuals. There was also a statistically significant association between serum Ferritin and Thyroid hormone levels (Total T3 and Total T4) with (p<0.05). Conclusion: Serum Ferritin levels are significantly reduced in patients with Hypothyroidism. Thus, serum Ferritin can be used as an effective diagnostic marker in patients with Hypothyroidism, which can be used for diagnosis, monitoring and follow up of treatment in Hypothyroids, as well as for early detection of Iron deficiency anaemia, thereby preventing the development of dementia and cognitive decline in Hypothyroid individuals by early intervention.