Bone mineral density and metabolism in levothyroxine-treated adolescent girls with euthyroid diffuse goiter

Abstract

Introduction: Bone and mineral metabolism is influenced by thyroid hormones, and levothyroxine (LT₄) therapy may be associated with reduced bone mass in postmenopausal women.
Material and methods: The aim of the study was to assess the influence of one year of LT₄ treatment in a group of 21 adolescent girls with euthyroid diffuse goiter. Lumbar (L₂-L₄) and total body bone mineral density (TOBMD) (Lunar - DXA), serum PTH, osteocalcin, bone alkaline phosphate, vitamin D₃, calcium, and phosphorus levels and urinary excretion of Ca, P, and hydroxyproline were measured before and after one year of combined LT₄ and iodine treatment.
Results: Patients were matched for age, sex, BMI, and maturation status, with controls treated with iodine only. Markers of bone turnover changed in a similar manner in both groups. There was no significant difference in TOBMD value after one year of therapy between LT₄ treated group and controls. Densitometric lumbar spine parameters increased significantly after 12 months in both groups, with no significant differences between them.
Conclusion: It can be concluded that one year of LT₄ treatment of adolescent girls with euthyroid diffuse goiter does not have a negative impact on their bone remodelling and metabolism.
(Pol J Endocrinol 2010; 61 (1): 14-19)