Comparative study of lipid profile between clinical and subclinical hypothyroidism
Keywords:Hypothyroidism, L- Thyroxin therapy, Metabolic syndrome, Subclinical hypothyroidism, Thyroid stimulating hormone
Background: Subclinical hypothyroidism (SH) is characterized by elevated levels of serum thyroid stimulating hormone in the presence of normal thyroxin levels. Subclinical hypothyroidism is often associated with elevated total cholesterol and other lipid profile parameters. This study was done to evaluate the lipid metabolism in subclinical hypothyroidism.
Methods: This case control study was done to compare the lipid profile parameters between subclinical and overt hypothyroidism cases attending the outpatient facility of our tertiary care hospital of our medical college in Puducherry. Newly diagnosed cases of hypothyroidism were selected by convenient sampling. A total of 37 SH cases and 31 overt hypothyroidism cases were included. Blood samples were drawn to measure lipid profile. A 2D echocardiogram was done to evaluate cardiac function. Ultrasonogram was done to evaluate fatty liver.
Results: The mean age of the participants in the subclinical hypothyroidism group was 34.2±12.2 years while in the clinical hypothyroidism group was 35.7±9.8 years. About 13.5% of the participants in subclinical hypothyroidism group and 12.9% of the participants in clinical hypothyroidism had fatty liver in ultrasound. A significant difference was observed in the mean values of total cholesterol, triglycerides and LDL levels between clinical and subclinical hypothyroidism.
Conclusions: This study highlights the need for screening of subclinical hypothyroidism in order to prevent the incidences of cardiovascular complications and other diseases like metabolic syndrome.
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