Androgens and bone mineral content in patients with subtotal thyroidectomy for benign nodular disease

To investigate the influence of thyroid surgery on the skeleton and different hormones a well characterized patient group of 24 women was selected who had undergone subtotal thyroidectomy for euthyroid benign nodular disease and remained euthyroid after the operation. Bone mineral content was determined in lumbar vertebrae, femoral neck and radius by dual and single photon absorptiometry. The serum levels of calcitonin, dehydroepiandrosterone, dehydroepiandrosterone-sulphate, androstenedione, total testosterone, cortisol and 25-hydroxyvitamin D were measured. A control group was created of 48 healthy female subjects. No reduction in bone mass was observed at the measured sites compared to appropriate controls. Beside normal bone mineral content significantly elevated serum levels of dehydroepiandrosterone (27.4 +/- 10.4 vs. 20.8 +/- 6.9 nmol/l) and androstenedione 9.3 +/- 3.3 vs. 6.6 +/- 2.2 nmol/l) were found without any clinical sign of androgen excess. There was no correlation between bone mineral content and these androgen levels. The serum calcitonin levels of all patients were low. With regard to the previously reported interactions among androgen, calcitonin and bone metabolism, our results raise the possibility of a relationship between higher androgen levels and preserved bone mass in these patients, while normal bone mineral content and calcitonin deficiency in these patients does not inevitably indicate that calcitonin does not affect bone tissue in adults.