Study of serum lipid profile in subclinical hypothyroidism

Objective: It has been known that overt hypothyroidism is associated with hyperlipidemia, replacement therapy with Levothyroxine significantly reverses lipid metabolism abnormalities. But no clear consensus has been established regarding the treatment of Subclinical Hypothyroidism subjects. This is due to the fact that there are no data from large trials on whether and to what degree Subclinical Hypothyroidism affects lipid profile. This study is aimed to provide a look at the status of Lipid Profile in the case of Subclinical Hypothyroidism.

Materials and Methods: Total 100 subjects were recruited and divided into 2 groups. 50 Patients with Subclinical Hypothyroidism were considered as the cases and 50 healthy people as the controls. Serum TSH was analysed by sandwich electrochemiluminescence immunoassay method. Serum cholesterol, triglyceride and HDL were estimated by enzymatic colorimetric method, LDL was calculated by using friedewald formula.

Results: Serum cholesterol, LDL were higher (P<0.0001) and HDL (P<0.0001) was lower in Subclinical Hypothyroid patients (meanSD= 199.927.8 mg/dl, 130.026.3mg/dl, 44.29.1 mg/dl respectively) compared to healthy controls (meanSD= 170.116.8 mg/dl, 97.314.7 mg/dl, 54.210.0 mg/dl respectively). A significant correlation was found between the levels of TSH and Serum Cholesterol (r=0.5101, P<0.0001), LDL (r=0.5637, P<0.0001) and a significant negative correlation was found between the levels of TSH and HDL (r=-0.4525, P<0.0001).

Conclusion: Subclinical hypothyroidism is associated with elevated levels of Serum Total Cholesterol and LDL which is atherogenic in nature, and low level of HDL. This may further increase the risk of development of atherosclerosis.

Subclinical Hypothyroidism, lipid profile, Total Cholesterol, LDL, HDL, dyslipidemia