A cross-sectional study of hematological profile in patients with thyroid dysfunction

Background: Thyroid hormones play a key role in hematopoiesis by regulating erythropoietin production and erythroid proliferation. Thyroid dysfunction is associated with anemia and other hematological abnormalities through impaired marrow activity, nutritional deficiencies, and altered iron metabolism. Aims and Objectives: To evaluate the effect of hypothyroidism and hyperthyroidism on hematological parameters and to determine the prevalence, type, and severity of anemia. Materials and Methods: A cross-sectional study was conducted from June to August 2025 at Navodaya Medical College Hospital and Research Centre, Raichur. A total of 127 participants aged 18–80 years were included and categorized into hypothyroid (n=59), hyperthyroid (n=10), and euthyroid controls (n=58) groups. Thyroid function tests were performed using the electrochemiluminescence immunoassay method. Hematological parameters were analyzed using a five-part automated analyzer, and peripheral blood smears were examined for anemia classification. Statistical analysis was done using Statistical Package for the Social Sciences version 16. Results: Hypothyroidism was more prevalent (46.46%) than hyperthyroidism (7.87%). Hemoglobin, red blood cell count, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin concentration showed a declining trend in thyroid dysfunction but were not statistically significant. Significant leukopenia was observed in hypothyroid patients (P=0.02), while thrombocytopenia was significant in hyperthyroid patients (P=0.03). Anemia was more common in hypothyroid (49.6%) than hyperthyroid (3.9%) patients. Microcytic hypochromic anemia was the most common type (P<0.0001). Conclusion: Thyroid dysfunction, particularly hypothyroidism, is associated with hematological abnormalities and increased anemia prevalence, predominantly of the microcytic hypochromic type. Routine hematological screening can facilitate early diagnosis and improve patient outcomes.