Serum lipids and thyrotropin in women with coronary artery disease

Abnormalities of thyroid function are associated with changes in lipid concentrations and in the incidence of ischaemic heart disease. Whether lipid concentration and thyroid function are related when thyroid function is normal in ischaemic heart disease is uncertain. This study was undertaken to investigate the relationship between thyroid function, serum lipids and ischaemic heart disease in euthyroid women. Forty-six euthyroid patients were studied. Patients with diseases known to affect lipid levels or receiving drugs known to alter lipid or thyroid metabolism were excluded. Twenty-three had ischaemic heart disease (IHD) and were matched with 23 controls. Correlations were found between thyrotropin (TSH) and cholesterol (P = 0.05) low density lipoprotein (LDL) (P = 0.09) and triglyceride (P = 0.009) in the IHD group but not between any serum lipids and TSH in the control group. Analysis of covariance showed a statistically significant difference between groups of the association between cholesterol and TSH (P < 0.05 (slope) P < 0.001 (means)), LDL and TSH (P < 0.005 (means)) and between triglyceride and TSH (P < 0.05 (means)). This study suggests that TSH within the normal range is having a statistically significant effect on lipid levels in women with ischaemic heart disease.