State of bone tissue in patients with thyrotoxicosis syndrome

Abstract

Оbjective. To determine the influence of thyroid functional state on bone mineral density indexes from data of ultrasound densitometry and laboratory methods of research.Materials and methods. 80 patients of reproductive age with thyrotoxicosis syndrome were recruited. The thyroid functional state was estimated by means of determination of thyroid-stimulating hormone (TSH) basal concentrations and free thyroxine in the blood serum. Subjects were invited to attend quantitative ultrasound densitometry (Sahara), and a fasting blood sample from which osteocalcin, serum N-terminal propeptide of type 1 procollagen and crosslinks were also measured.Results. Frequency of bone mineral density disorders in patients with thyrotoxicosis syndrome was 52,7%, including osteopenia in 40% and osteoporosis in 12.7%. A basic factor that results in the decline of bone mineral density in patients with thyrotoxicosis syndrome is excessive products of thyroid hormones, and also TSH-suppressive doses of levothyroxine. Ultrasound densitometry showed significant decrease of bone mineral density indexes and increase of frequency of osteopenia and osteoporosis as compared to healthy persons.Conclusions. Complex approach is the first brought to the estimation of bone metabolism state in patients with thyrotoxicosis syndrome. It contains an ultrasound densitometry and laboratory methods of research. Set factors (excessive products of thyroid hormones, reception of preparations of thyroid hormones in TSH-suppressive doses) and mechanisms of negative influence (stimulation of osteoclastic activity, decline of osteoblastic activity) on the state of bone metabolism in patients with thyrotoxicosis syndrome.