Thyroid Dysfunction and Cardiometabolic Risk: A Comparative Analysis of Lipid Profile, Glycemic Markers, and Atherogenic Indices in Hypothyroidism and Hyperthyroidism
Sridurga Mattyvanan, Hari Shankar, Sivaa Rajendran, V. ShanmugapriyaAbstract
Background and Aims:
Thyroid dysfunction is a common endocrine disorder affecting glucose homeostasis and lipid metabolism, thereby influencing cardiovascular risk. This study compared lipid profile, glycemic status, and derived atherogenic indices in patients with hypothyroidism and hyperthyroidism and evaluated their associations with thyroid dysfunction. Hypothyroidism was defined as elevated thyroid-stimulating hormone (TSH) with low FT4 concentrations, whereas hyperthyroidism was defined as suppressed TSH with elevated FT4 and/or FT3 concentrations according to institutional laboratory reference ranges.
Materials and Methods:
This cross-sectional study included 81 patients attending a tertiary care hospital, comprising 41 with hypothyroidism and 40 with hyperthyroidism. Serum thyroid parameters (FT3, FT4, and TSH), lipid profile components (total cholesterol [TC], low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], and triglycerides [TG]), and glycated hemoglobin (HbA1c) were measured. Derived atherogenic indices, including Castelli risk index-I (CRI-I), CRI-II, atherogenic coefficient, atherogenic index of plasma, and non-HDL cholesterol, were calculated. Statistical analysis was performed using the Shapiro–Wilk test, independent-samples Student’s
Results:
Patients with hypothyroidism had significantly higher TC, TG, LDL-C, and HbA1c levels and lower HDL-C levels, compared with patients with hyperthyroidism (
Conclusion:
Hypothyroidism is associated with adverse lipid alterations, higher HbA1c, and elevated atherogenic indices, suggesting greater cardiovascular risk compared with hyperthyroidism.