Steroids, sex hormone-binding globulin, homocysteine, selected hormones and markers of lipid and carbohydrate metabolism in patients with severe hypothyroidism and their changes following thyroid hormone supplementation.

Abstract

Laboratory markers of thyroid function, selected steroid hormones, sex hormone-binding globulin (SHBG), homocysteine, prolactin, major markers of lipid- and glucose metabolism and of insular-growth hormone axes were investigated in fasting sera from 16 female patients with severe hypothyroidism after thyroidectomy because of thyroid cancer. The results obtained in severe hypothyroidism within 5-6 weeks after withdrawal of thyroid substitution therapy before control scintigraphy were compared with those obtained after correction of thyroid function. Elevated levels of homocysteine and prolactin in hypothyroidism significantly decreased after correction, while SHBG concentration increased. Correction of thyroid function led to significant changes of growth hormone and immunoglobulin F1 (decrease and increase, respectively), while insulin and proinsulin increased only insignificantly. Elevated levels of total cholesterol and triglycerides in hypothyroidism were normalized, along with a significant increase in high density lipoprotein (HDL)-cholesterol. As revealed by correlation and factor analyses, different relationships characterizing both states were found in hypothyroidism and after correction of thyroid function. A strong inverse relationship between homocysteine and free thyroid hormones confirms the effect of thyroid hormones on homocysteine metabolism. No such inverse relation was found in euthyroid state, however. Similarly, in hypothyroidism only, dehydroepiandrosterone sulfate correlated positively with immunoglobulin F1 and homocysteine and negatively with thyroid hormones and SHBG.