REDUCED FOREARM BONE-MINERAL CONTENT AND BIOCHEMICAL-EVIDENCE OF INCREASED BONE TURNOVER IN WOMEN WITH EUTHYROID GOITER TREATED WITH THYROID-HORMONE

We used single‐photon absorptiometry to assess forearm bone mineral content (BMC/BW) (arbitrary units normalized for bone width) at a proximal site (PBMC/BW) and at a more distal site (DBMC/BW) in 60 women treated with 25–50 μg T3 or 50–100 μg T4 for euthyroid goitre, in 13 untreated goitre patients, and in 2 controls matched for age and menopausal state for each goitre patient. BMC/BW was not significantly different between untreated goitre patients and controls. In 36 premenopausal patients, treated for 5.8 |Mp 5.4 years (mean |Mp SD) a slight decrease in PBMC/BW of about 5% compared to controls was observed (PBMC/BW 1.42 |Mp 0.19 vs 1.49 |Mp 013, P< 0.05). In 24 postmenopausal patients, treated for 10.0 |Mp 5.8 year, a 20% deficit in BMC/BW compared to controls was found (DBMC/BW 0.80 |Mp 0.18 vs 1.06 |Mp 0.20, P < 0.001 and PBMC/BW 1.14 |Mp 0–20 vs 1.42 |Mp 0.19, P < 0.001). Biochemical indices of bone metabolism in 43 pre and post‐menopausal patients and 43 controls showed in the patients a higher serum alkaline phosphatase activity (AP) (P < 0.01 and P < 0.05) and serum osteocalcin (NS and P < 0.05). AP was negatively correlated with TSH levels and, in postmenopausal patients, with DBMC/BW and PBMC/BW. Our results suggest that treatment of euthyroid women with moderate doses of thyroid hormone increases bone turnover with clear adverse effects on bone mineral status in postmenopausal patients. Copyright © 1990, Wiley Blackwell. All rights reserved