Serum vitamin B12 levels and some biochemical markers in Iraqi females with subclinical hypothyroidism

Subclinical hypothyroidism (SCH) is characterized by increased conce n t r ation of thyroid-stimulating hormone (TSH) levels, while thyroid hormones (free thyroxine (T 4 ) and free triiodothyronine (T 3 )) conce n t r ation remain s within the reference ranges. D eficiency in vitamin B 12 is common in patients with autoimmune diseases, including the thyroid disorder autoimmune hypoth y roidism. Low level s of vitamin B 12 are reported in patients with hypothyroidism but with varied prevalence. Thus routine scree n ing, and early detection of vitamin B 12 level c an be helpful in prevent ing the further progression of sub c linical hypothyroidism. The aim of the present study is to detect the prevalence of vitamin B 12 deficiency in patients with thyroid diseases with s ubclin i cal hypothyroidism. 100 subjects divided into 50 patients with subclinical hypothyroidism (females) and 50 control subjects whose age and sex matched the patients were i n cluded in the study. The serum levels of vitamin B 12 , ferritin , TSH, free T 3 and free T 4 were estimated through electro chemiluminescence by a cobas e 411 analyzer fully automated to identify cases of SCH. while zinc and magnesium were estimated by semi-automated photometry . In SCH patients with t hyroid diseases , both free T 3 and T 4 levels were within the normal range, whereas TSH levels were in the range of 4.9 – 11.2 mIU / L . Significantly low levels of serum vitamin B 12 ferritin were found in cases of subclinical hypothyroidism ( P < 0.0001). Based on the results of our study , we conclude that there is a higher prevalence of deficiency in vitamin B 12 , serum zinc , serum magnesium and serum ferritin in SCH thyroid disorder patients . Hence we recommend routine laborat ory testing and early detection of vit a min B12 deficiancy would be useful in deciding appropriate management measures .