Abstract
Background: Thyroid hormones play a major role in the metabolism of lipids and deranged lipid profile can, in turn, result in various cardiovascular diseases. The association between elevated LDL and coronary artery disease (CAD) risk is well established. However, the correlation between the changes in the thyroid hormone levels and lipid profile needs to be studied in detail.

Aim and Objectives: This study was conducted with the objective of estimating the serum levels of total cholesterol, triglycerides, LDL, HDL, and VLDL in hyperthyroid and hypothyroid individuals and to compare it with the euthyroid population.

Materials and Methods: A cross-sectional study was conducted among 165 study subjects who included newly diagnosed patients with untreated hypothyroidism and hyperthyroidism and controls were selected from the bystander population. Serum TSH, serum total cholesterol, serum LDL, serum triglycerides, serum VLDL and serum HDL were assessed. The baseline characteristics and blood investigation values were compared among the three groups using ANOVA and were expressed in mean ± standard deviation. The association between the various parameters in different groups was evaluated using Pearson’s correlation coefficient. P < 0.05 was considered statistically significant.

Results: Among the 165 subjects studied, majority belonged to the age group of 30–39 years and majority of the study subjects were females. The mean serum levels of total cholesterol (216.86 ± 21.99 mg/dl), LDL (142.49 ± 19.09 mg/dl), triglycerides (156.31 ± 26.33 mg/dl) and VLDL (31.26 ± 5.25 mg/dl) were significantly higher in the hypothyroid group compared to the control subjects (P = 0.000). The mean serum levels of total cholesterol, LDL, triglycerides, and VLDL were significantly higher in the hypothyroid group compared to the control subjects (P = 0.000).

Conclusion: Hypothyroidism demonstrates an atherogenic lipid profile with a positive correlation with serum TSH values and lipid profile. Since altered lipid profile can predispose to cardiovascular diseases, screening for these in individuals with thyroid dysfunction especially hypothyroidism needs to made mandatory.

Key words: Lipid Profile Anomalies; Thyroid Dysfunction; Hypo and Hyperthyroidism