[The effect of levothyroxine suppression therapy for benign thyroid nodules on bone metabolism in premenopausal women].
OBJECTIVE
This prospective study was designed to investigate the effect of levothyroxine suppression therapy for benign thyroid nodules on markers of bone turnover in premenopausal women.


METHODS
The study included 28 premenopausal women who received levothyroxine suppression therapy for benign thyroid nodules for one year. The size of the thyroid gland and nodules, biochemical markers of bone turnover and urinary calcium excretion were measured before and after levothyroxine suppression therapy.


RESULTS
No significant adverse effects were seen during levothyroxine treatment. Decreases in total thyroid volume and the size of the nodules were not significant at the end of treatment. Although levothyroxine suppression therapy did not result in changes in serum levels of calcium and phosphor, and urinary calcium excretion, bone turnover markers, namely serum osteocalcin and urinary deoxypyridinoline levels, increased significantly. Serum intact parathyroid hormone levels showed a minimal decrease, which was not statistically significant.


CONCLUSIONS
Data from our study suggest that levothyroxine suppression therapy is associated with increased osteoblastic and osteoclastic activity in premenopausal women with benign thyroid nodules.
Akinci
Bariş
B
Department of Internal Medicine, Medicine Faculty of Dokuz Eylül University, Izmir, Turkey. baris.akinci@deu.edu.tr
Demir
Tevfik
T
Cömlekçi
Abdurrahman
A
Karaoğlu
Oğuzhan
O
Seçil
Mustafa
M
Yeşil
Sena
S
D000596:Amino Acids / Q000652:urine; D015415:Biomarkers; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000097:blood / Q000652:urine; D005260:Female; D006801:Humans; D015675:Osteocalcin / Q000097:blood / Q000187:drug effects; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D017697:Premenopause; D011446:Prospective Studies; D013961:Thyroid Gland / Q000033:anatomy & histology / Q000187:drug effects; D016606:Thyroid Nodule / Q000188:drug therapy*; D013974:Thyroxine / Q000009:adverse effects / Q000627:therapeutic use*
D000596:Amino Acids; D015415:Biomarkers; D010281:Parathyroid Hormone; D015675:Osteocalcin; D010758:Phosphorus; C036020:deoxypyridinoline; D013974:Thyroxine; D002118:Calcium