Akademik Veri Yönetim Sistemi
European Journal of Internal Medicine, cilt.8, sa.1, ss.29-34, 1997 (SCI-Expanded)
The aim of our study was to elucidate whether endogenous subclinical hyperthyroidism due to an autonomously functioning thyroid nodule affects bone metabolism and is a risk factor for osteoporosis and if so, whether it differs according to sex and menopausal status. In this cross-sectional study measurements of bone mineral density (BMD) were performed in 9 premenopausal, 12 post-menopausal women and it 7 men who had all endogenous subclinical hyperthyroidism due to an autonomously functioning thyroid nodule. Neither of them had a past history of hyperthyroidism not had been treated for any thyroid disorder. All of them were euthryroid by clinical and laboratory evaluation. They had single or multiple solid nodules or ultrasound and single or multiple autonomous (suppressing the surrounding tissue) nodules or scintigraphy. Lumbar spine BMD was measured by quantitative computerized tomography. The levels of triiodothyronine (T3), tetraiodothyronine (T4), free T3 (fT3), free T4 (fT4), thyrotropin (TSH), parathyroid hormone (PTH), serum calcium (Ca), alkaline phosphatase (ALP), cholesterol, ferritin, osteocalcin (OC) and urine calcium-creatinine ratios were determined. The results were compared with the age and sex matched controls in each subgroup (premenopausal, post-menopausal females and males). Bone mineral density of premenopausal females did not show any difference in comparison with age and sex matched controls. It was found to be significantly (p < 0.05) lower in post-menopausal females and insignificantly low in males when compared with age and sex matched controls. A statistically significant increase was found in OC levels in each of the three subgroup when compared with controls (p < 0.05). In conclusion, the results of our study revealed that endogenous subclinical hyperthyroidism due to an autonomously functioning thyroid nodule may affect bone metabolism and may be an additional risk factor for osteoporosis especially in post-menopausal females.