Prevalence of Anemia and Its Etiology in Patients with Primary Hypothyroidism: A Cross-sectional Observational Study in a Tertiary Care Hospital of Eastern India

Introduction: Anemia is a global public health problem and hypothyroidism is the most common thyroid disorder in India (prevalence 11%) which adversely affects erythropoiesis.Aims and objectives: This cross-sectional observational study was conducted to determine the prevalence, etiology, and type of anemia in primary hypothyroidism.Materials and methods: Ninety adult male and female patients who presented with primary hypothyroidism were included in this study based on certain inclusion and exclusion criteria.Study variables included were thyroid function tests, such as free thyroxine and thyroid-stimulating hormone (TSH), complete blood count, serum iron, ferritin, and vitamin B12 levels in both cases and control populations, respectively.Mean and standard deviation were calculated for each parameter with appropriate statistical tests to establish the association among the study variables.Result: Mean hemoglobin level was 10.07 gm/dL, mean serum ferritin level was 63.2 ng/mL, and mean serum vitamin B12 level was 332.8 pg/ mL in patients with primary hypothyroidism.A p-value <0.05 was considered statistically significant.No statistically significant difference was observed in serum iron levels.Overall, normocytic normochromic anemia was more prevalent type in patients with primary hypothyroidism, while microcytic hypochromic anemia, mostly due to iron deficiency, was more prevalent in female population.A moderately strong negative correlation was found between serum TSH and serum ferritin in both males (r = -0.616)and females (r = -0.541),while a weak negative correlation between serum TSH and vitamin B12 was found in both sexes (males -0.403 and females -0.372). Conclusion:There was significant difference in hemoglobin levels in patients with primary hypothyroidism as compared with control group, and normocytic normochromic morphology was the most prevalent type of anemia.Hence, patients having thyroid disorders should undergo routine screening for anemia and serum ferritin assay that help in proper management of this metabolic disease.