UNLABELLED: It has been suggested that chronic treatment with L-thyroxine (L-T4) could be implicated in reducing bone mineral density (BMD). The purpose of this longitudinal study was to determine whether appendicular and axial BMD is decreased by L-T4 treatment in adolescent girls. Thirteen adolescent girls with subclinical hypothyroidism caused by chronic lymphocytic thyroiditis were enrolled in the study at the median age of 13.4 years (range 9.2-18.1 years). L-T4 was administered in a single dose of 1-5 micrograms/kg daily. BMD was evaluated at the distal one-third of the non-dominant radius by single photon absorptiometry (SPA) and at the lumbar spine (L2-4) by dual energy X-ray densitometry (DEXA). Osteocalcin levels were measured to assess bone turnover before and during L-T4 treatment. Before the start of therapy, mean BMD at both the radial and lumbar level was not significantly different from that of a control group (median age 13.0 years; range 9.0-18.5 years). during L-T4 therapy for 2-5 years, BMD did not change at any site. Before treatment, osteocalcin levels were not significantly different from those of controls and did not change during follow up. CONCLUSION: Long-term L-T4 therapy in adolescent girls has no adverse effect on BMD and bone turnover. Our data indicate that attainment of peak bone mass is not impaired by L-T4 administration.
UNLABELLED: It has been suggested that chronic treatment with L-thyroxine (L-T4) could be implicated in reducing bone mineral density (BMD). The purpose of this longitudinal study was to determine whether appendicular and axial BMD is decreased by L-T4 treatment in adolescent girls. Thirteen adolescent girls with subclinical hypothyroidism caused by chronic lymphocytic thyroiditis were enrolled in the study at the median age of 13.4 years (range 9.2-18.1 years). L-T4 was administered in a single dose of 1-5 micrograms/kg daily. BMD was evaluated at the distal one-third of the non-dominant radius by single photon absorptiometry (SPA) and at the lumbar spine (L2-4) by dual energy X-ray densitometry (DEXA). Osteocalcin levels were measured to assess bone turnover before and during L-T4 treatment. Before the start of therapy, mean BMD at both the radial and lumbar level was not significantly different from that of a control group (median age 13.0 years; range 9.0-18.5 years). during L-T4 therapy for 2-5 years, BMD did not change at any site. Before treatment, osteocalcin levels were not significantly different from those of controls and did not change during follow up. CONCLUSION: Long-term L-T4 therapy in adolescent girls has no adverse effect on BMD and bone turnover. Our data indicate that attainment of peak bone mass is not impaired by L-T4 administration.
Authors: G Theintz; B Buchs; R Rizzoli; D Slosman; H Clavien; P C Sizonenko; J P Bonjour Journal: J Clin Endocrinol Metab Date: 1992-10 Impact factor: 5.958
Authors: Hassan M Salama; Soha A El-Dayem; Hala Yousef; Ashraf Fawzy; Laila Abou-Ismail; Dalia El-Lebedy Journal: Arch Med Sci Date: 2010-06-30 Impact factor: 3.318