The effect of thyroid hormones on lipoprotein(a) plasma concentrations and the other parameters of lipoprotein metabolism was studied in 158 patients with thyroid dysfunction and in 37 euthyroid controls (cross-sectional study). Multiple regression analysis revealed that 65.5 % of the variability in lipoprotein(a) levels were predicted by changes in lipoprotein(a) phenotypes (60.5 %), thyrotropin (3.5 %), and age (0.8 %). The lipid parameters, however, showed no significant effect on lipoprotein(a). A subgroup analysis on samples from patients with large lipoprotein(a) isoforms showed that 28% of the variability in lipoprotein(a) concentrations could be explained by changes in thyroid function (19.1 %), age (6.5 %) and triglycerides (3.5 %). Much stronger correlations were found between thyrotropin and total cholesterol, low density lipoprotein cholesterol or apolipoprotein B respectively (R2=0.951 for low density lipoprotein cholesterol, R2=0.801 for apolipoprotein B). Our data suggest that thyroid hormone is a significant modulator of lipoprotein(a) metabolism. However, different mechanisms are responsible for the change in lipoprotein(a) levels and for the decrease in total-and low density lipoprotein cholesterol levels.
Print ISSN: 1434-6621
Volume: 36, 09/1998
Pages: 731 - 735