Qom University of Medical Sciences Journal

Background and Objectives: Subclinical hypothyroidism affects               6-17% of general population. Given that mild increase in TSH level leads to dyslipidemia, it can be associated with cardiovascular disease. The present study aimed to investigate the effect of early levothyroxine treatment on blood lipid profile in subclinical hypothyroid patients (with serum TSH level less than 10mIU/l and normal lipid level.

Methods: In this clinical trial, 82 subclinical hypothyroid patients with normal FT4 (free T4), TSH of 5.2-10mIU/L and normal lipid level, were investigated. The patients were randomly divided into experimental and control groups. The experimental group received levothyroxine for 2 months and then both groups were evaluated. Data were analyzed using Kolmogorov-Smirnov and t tests. The level of significance was considered less than 0.05.

Results: The mean age in experimental and control groups were 39.68±9.25 and 37.63±9.99 years, respectively. FT4 level significantly increased, and HDL, LDL, triglyceride, and cholesterol levels significantly decreased in the experimental group after two months of treatment with levothyroxine.

Conclusion: The results of this study revealed that levothyroxine treatment in subclinical hypothyroid patients significantly decreases serum levels of HDL, LDL, triglyceride, and cholesterol.