Changes of bone mineral density, quantitative ultrasound parameters and markers of bone turnover during treatment of hyperthyroidism.

Background: The extent of reversibility of loss of bone mass density (BMD) in hyperthyroid patients after treatment is not clear. Methods: The bone density measured by dual X-ray absorptiometry (DXA), the parameters of quantitative ultrasound (QUS) and biochemical markers of bone turnover of 22 patients were measured before and after one year of treatment with thiamazole and levothyroxine. Results: The mean BMD of lumbar spine, femoral neck, Ward triangle and total hip bone density increased by 5-9, 3.8, 3.0 and 6.7%, respectively, after one year of treatment, all significant increases except the increase in Ward triangle bone mass density. There was no significant change in QUS parameters, although the increase in broadband ultrasound attenuation (BUA) of the left and right calcaneus of 5.2 and 4.2%, respectively, suggests reversibility in the long term. Urinary pyridinoline cross-links declined significantly and normalised after treatment. Bone-specific alkaline phosphatase declined after an initial rise, not (yet) reaching normal values after one year of treatment. Conclusion: The decline in BMD in hyperthyroid patients measured by DXA seems to be reversible after treatment of hyperthyroidism, whereas a change in the QUS parameters, probably also an indicator of bone elasticity and architecture, could not be found.