A study on serum homocysteine and oxidized LDL as markers of cardiovascular risk in patients with overt hypothyroidism

Abstract

Abstract Objectives Hypothyroidism is the most common endocrine disorder worldwide. Hypothyroisim increases cardiovascular risk, thus the study focuses on the assessment of cardiovascular risk factors such as serum Homocysteine, serum Oxidized LDL and Lipid profile and their correlation with TSH levels. Timely evaluation of these risk predictors would help in reducing cardiovascular disease morbidity and mortality in hypothyroidism. Methods This was a hospital based cross-sectional study consisting of Forty newly diagnosed patients with overt hypothyroidism in the age group of 20–60 years attending Medicine OPD were included as cases and Fifty healthy age and gender matched healthy controls participated as controls in the study. A written and informed consent to all the participants of both the groups was taken after explaining the purpose and details of the study. The Thyroid profile was assessed by CLIA-based MAGLUMI- 1000 analyzer and Serum total cholesterol, triglycerides and high-density lipoproteins were analyzed in Fully automated clinical chemistry analyzer EM-200 by using commercially available kits. LDL was calculated indirectly using Friedwalds equation. Commercially available ELISA-based kits were used for analysis of serum Homocysteine and serum oxidized-LDL. Results Elevated levels of serum homocysteine (p<0.0001), Oxidized LDL (p<0.0001) were found in newly diagnosed overt hypothyroid patients as compared to controls whereas significant elevated levelsof TC, TG, LDL, and VLDL (p<0.0001) and decrease in HDLcholesterol (p<0.0001) were reported in newly diagnosed newly diagnosed overt hypothyroid patients. Conclusions We concluded that the association of hyperhomocysteinemia and lipid abnormalities occurring in hypothyroidism may represent a dynamic atherogenic state and thyroid hormone failed to completely normalize Hcy levels. Thus, elevated plasma homocysteine levels may be an independent risk factor for the accelerated atherosclerosis seen in hypothyroidism. In addition, we found that the circulating ox-LDL levels were elevated in untreated hypothyroidism and they tend to be higher in thyroid dysfunction.