Homocysteinemia in relation to anemia in hypothyroid patients

Abstract

Background Anemia and hypothyroidism are both common diseases in the community. Homocysteine (HCY) levels are increased in patients with hypothyroidism and methylenetetrahydrofolate reductase (MTHFR) deficiency is the most common genetic cause of hyperhomocysteinemia. The aim of the present study was to evaluate the level of serum HCY in patients with hypothyroidism and to study the relation of associated anemia with the serum level of HCY and MTHFR gene in patients with hypothyroidism. Patients and methods The study was conducted on 60 adult women attending the Endocrinology Outpatient Clinic of Al-Zahraa Hospital between September 2014 and June 2015 for proper diagnosis and management. Individuals of the study were divided into two main groups: group I (GI) with 30 hypothyroid patients, where 13 of them were postsurgical cases, and group II (GII) with 30 euthyroid individuals as a control group. Diagnosis was based on thyroid-stimulating hormone level reference values. Patients in GI were further classified into two subgroups: mild hypothyroid (subgroup I) and overt hypothyroid (subgroup II). Patient and control groups also were classified into anemic and nonanemic subgroups according to hemoglobin levels. The selected hypothyroid patients were women under thyroid hormone replacement therapy. Blood sample was obtained for proper investigations. Complete blood count, routine blood chemistry, serum iron level, thyroid function tests, vitamin B12 level, serum homocysteine (HCY), and MTHFR were performed. We performed a pilot study on MTHFR gene polymorphism. The C677T MTHFR gene mutation was detected in three of 10 patients and in two of 10 controls. No evidence of TT MTHFR gene mutation was observed in both patient and control groups. IBM SPSS statistics (version 23.0, USA, 2015) was used for data analysis. Results revealed the presence of anemia according to hemoglobin level (<12 g/dl). In patients group (GI), 50% (15/30) as compared with 13.3% (4/30) in the control group (GII) had anemia. Serum iron level in patients group (GI) was deficient in 40% (11/30), whereas deficient in 16.7% (5/30) in control group (GII). Vitamin B12 deficiency was found to be 44% (11/25) in patients group (GI), whereas in the control group (GII) was 6.7% (2/30). Analysis by Wilcoxon's rank sum test, homocysteine (HCY) serum level showed a highly significant increase among patients (GI) as compared with control (GII). Ranked Spearman's correlation test for the patients (GI) and control (GII) showed a significant negative correlation between homocysteine (HCY) and MTHFR serum levels, whereas the correlation with red cell indices parameters was insignificant. Serum iron and B12 levels were significantly correlated in patient group (GI). Pearson χ 2 tests were done between both patients and control groups for the presence of anemia, iron deficiency, and elevated serum homocysteine (HCY) level and all revealed statistically significant results. Conclusion There is no significant correlation between homocysteinemia and anemia. However, the strong association between anemia and hypothyroidism is attributed mainly owing to combined iron and vitamin B12 deficiencies. This might explain the decreased response to treatment among the selected hypothyroid patients.