The importance of carotid intima ? media thickness at the detection of early atherosclerosis in the patients with subclinical hypothyroidism.

Purpose: Subclinical hypothyroidism ( SHT ) is associated with enhanced risk for arteriosclerotic cardiovascular disease. Aim of the present study was to assess carotid intima-media thickness ( IMT ) as well as the lipoprotein profile in a carefully selected group of SHT patients in comparison with matched euthyroid controls and asses the relationships between IMT and serum lipoprotein profile, TSH and age.Materials and Methods: This study is prospective design. Study subjects recruited from Düzce University Faculty of Medicine. 56 patients with SHT and 56 euthyroid subjects evaluated in study. Individuals over age 50 yr; obese ( BMI > 30 kg / m2 ) subjects; smokers; and those with hypertension, diabetes mellitus, renal and hepatic failure, or other systemic diseases were excluded from the study. Body mass indeks ( BMI ), total cholesterol ( TC ), LDL cholesterol ( LDL- C ), HDL cholesterol ( HDL- C ), trigylceride ( TG ), carotid IMT were measured in each group; and comparison made with 56 age - and sex - matched controlsResults: There were no significant differences regarding age, BMI , TG, HDL, fT3, fT4 values between the two groups. However, carotid intima - media thicknes, TC , LDL- C, and TSH values in patients with SHT were significant higher than euthyroid controls. Significant positive relationships were found between carotid intima - media thicknes and serum TC ( r = 0.306, P = 0.022 ) and LDL levels ( r = 0.268, P = 0.046 ) and age ( r= 446, P= 0.001Conclusion:The relationship between subclinical hypothyroidism and atherosclerosis is, however, still ambiguous. The elucidation of this problem is important as subclinical hypothyroidism is a relatively common condition, and if necessary early levothyroxine ( L- T4 ) substitution therapy given to adequately selected patients could prevent the development of atherosclerosis. Increased IMT is a non - invasive marker of arterial wall alteration, which can easily be assessed in the carotid arteries by ultrasound. We beleive that, L- T4 replacement therapy in the patients with SHT, who has elevated carotid İMT able to decrease cardiovascular disease morbidity and mortality. However, we think that, large population-based, placebo - controlled L - T4 replacement study can explain this subject more clearlyKey words: Subclinical hypothyroidism, early atherosclerosis, carotid artery intima -media thickness