Even people who only have a mildly overactive thyroid gland face an elevated risk for fractures in the hips or spinal area, a new review suggests.
Swiss reviewers searched databases for studies with thyroid function data and subsequent fractures.In the analysis that included more than 70,000 participants from 13 studies, subclinical hyperthyroidism
, was associated with an increased risk for hip and other fractures including spine. Subclinical hyperthyroidism
is a low serum thyroid-stimulating hormone (TSH) concentration and normal thyroid hormone T3 and T4 concentrations in a person without clinical symptoms.
Past research has shown that more pronounced cases of hyperthyroidism are associated with a raised fracture risk, the reviewers explained. But it hasn't been entirely clear whether the same holds true for milder forms of the condition.What is the link between thyroid disease and osteoporosis?
Thyroid hormone affects the rate of bone replacement. Too much thyroid hormone (T3 and T4) in the body speeds the rate at which bone is lost. If this happens too fast the osteoblasts may not be able to replace the bone loss quickly enough. If the thyroxine level in the body stays too high for a long period or the TSH level stays too low for a long period then there is a higher risk of developing osteoporosis. There is also some evidence that people with low thyroid-stimulating hormone (TSH) levels may lose bone at a faster rate than those with normal TSH levels even when the blood thyroxine measurement is within the normal range.