The relationship between increased risk of cardiovascular disease (CVD) and atherosclerosis in subclinical hypothyroidism (sHT) have been demonstrated in several studies. This relation was attributed to dyslipidemia which is common in sHT. Apo A1, apo B100, Lp (a), hsC-reactive protein (hsCRP), fibrinogen and total homocysteinemia (tHcy) are the main non-traditional cardiovascular risk factors. In addition, paraoxon 1 (PON 1) activity is an enzyme responsible for the anti-oxidant effect of HDL cholesterol. We aimed to investigate the effects of L-thyroxine (L-T4) treatment in women with sHT on the anthropometric and hemodynamic properties, lipid parameters, hsCRP, tHcy, fibrinogen and PON 1 activity. We enrolled 27 women with mild sHT referred to our out-patients clinics. All patients underwent TRH stimulation test. Subsequently patients were randomized into two groups. Twelve patients were received 100 μg/day levothyroxine (LT4) and 15 patients were observed without treatment for four months. LT4 dose adjustment was made to maintain TSH level between 0.5 and 2 μIU/ml in every month. We did not find any significant difference in anthropometric properties, lipid parameters, hsCRP, tHcy, fibrinogen and PON 1 activity between two groups at the end of the study. In conclusion, we could not find any evidence that levothyroxine treatment has beneficial effects on lipid parameters and non-traditional CVD risk factors in patients with mild sHT.
25 - 29 Apr 2009
European Society of Endocrinology