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

  • A. A. O. Nasir Al Iraqia University
  • A. Q. M. A. Qader Al Iraqia University
  • N. S. Humadi Al Iraqia University
Keywords: Zn, Mg, ferritin, free triiodothyronine, free thyroxine, subclinical hypothyroidism, thyroid stimulating hormone.

Abstract

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 .

References

Andrès, E., Serraj, K., Zhu, J., & Vermorken, A. J. M. (2013). The pathophysiology of elevated vitamin B12 in clinical practice. QJM, 106(6), 505–515.

Borawska, M., Markiewicz-Żukowska, R., Dziemianowicz, R., Socha, K., & Soroczyńska, J. (2012). Wpływ nawyków żywieniowych i palenia papierosów na stężenie cynku w surowicy krwi kobiet z chorobą Hashimoto [The influence of dietary habits and smoking on zinc level in serum of women with Hashimoto disease]. Bromatologia i Chemia Toksykologiczna, 45(3), 759–765 (in Polish).

Bushra, S. K., & Jamal, F. (2022). Study of mineral profile in patients with hypothyroidism. International Journal of Advanced Biochemistry Research, 6(1), 55–60.

Cinemre, H., Bilir, C., Gokosmanoglu, F., & Bahcebasi, T. (2009). Hematologic effects of levothyroxine in iron-deficient subclinical hypothyroid patients: A randomized, double-blind, controlled study. The Journal of Clinical Endocrinology and Metabolism, 94(1), 151–156.

Damayanti, D., Jaceldo-Siegl, K., Beeson, W. L., Fraser, G., Oda, K., & Haddad, E. H. (2018). Foods and supplements associated with vitamin B12 biomarkers among vegetarian and non-vegetarian participants of the Adventist Health Study-2 (AHS-2) calibration study. Nutrients, 10(6), 722.

Das, C., Sahana, P., Sengupta, N., Giri, D., Roy, M., & Mukhopadhyay, P. (2012). Etiology of anemia in primary hypothyroid subjects in a tertiary care center in Eastern India. Indian Journal of Endocrinology and Metabolism, 16(8), 361.

Dobosz, P., Konopka, W., Cenda, P., Nazim-Zygadło, E., & Kozok, A. (2009). Wpływ tonsillektomii na stężenie cynku w surowicy krwi. Otolaryngologia Polska, 63(1), 16–18.

Esposito, G., Dottori, L., Pivetta, G., Ligato, I., Dilaghi, E., & Lahner, E. (2022). Pernicious anemia: The hematological presentation of a multifaceted disorder caused by cobalamin deficiency. Nutrients, 14(8), 1672.

Javed, Z., & Sathyapalan, T. (2016). Levothyroxine treatment of mild subclinical hypothyroidism: A review of potential risks and benefits. Therapeutic Advances in Endocrinology and Metabolism, 7(1), 12–23.

LeFevre, M. L. (2015). Screening for thyroid dysfunction: U.S. preventive services task force recommendation statement. Annals of Internal Medicine, 162(9), 641–650.

Mallick, D., Choudhury, J., Bhattacharya, A., & Bandyopadhyay, D. (2023). Study of serum iron and vitamin B12 status in primary hypothyroidism at a tertiary care hospital in eastern region of India. National Journal of Physiology, Pharmacy and Pharmacology, 13(10), 2130–2134.

Nexo, E., Christensen, A. L., Hvas, A. M., Petersen, T. E., & Fedosov, S. N. (2002). Quantification of holo-transcobalamin, a marker of vitamin B12 deficiency. Clinical Chemistry, 48(3), 561–562.

Shakir, K. M., Turton, D., Aprill, B. S., Drake, A. J., 3rd, & Eisold, J. F. (2000). Anemia: A cause of intolerance to thyroxine sodium. Mayo Clinic Proceedings, 75(2), 189–192.

Sinha, M. K., Sinha, M., & Usmani, F. (2022). A study of the correlation between vitamin B12, folic acid and ferritin with thyroid hormones in hypothyroidism. International Journal of Health Sciences, 6(S2), 6877–6884.

Szczepanek-Parulska, E., Hernik, A., & Ruchała, M. (2017). Anemia in thyroid diseases. Polish Archives of Internal Medicine, 127, 352–360.

Tripathi, P., Saxena, N., Verma, M. K., & Singh, A. N. (2019). Association of vitamin B12, folate and ferritin with thyroid hormones in hypothyroidism. Annals of International Medical and Dental Research, 5(1), 1–6.

Turanjanin, D., Mijovic, R., Starcevic, I., & Tatalovic, V. (2024). Calcium and magnesium levels in patients with primary hypothyroidism. Medical Review, 77(3–4), 106–112.

Yilmaz, S., Ozan, S., Benzer, F., & Canatan, H. (2003). Oxidative damage and antioxidant enzyme activities in experimental hypothyroidism. Cell Biochemistry and Function, 21(4), 325–330.

Published
2026-03-26
How to Cite
Nasir, A. A. O., Qader, A. Q. M. A., & Humadi, N. S. (2026). Serum vitamin B12 levels and some biochemical markers in Iraqi females with subclinical hypothyroidism. Regulatory Mechanisms in Biosystems, 17(2), e26048. https://doi.org/10.15421/0226048