Here are some studies on the Thyroid/Osteoporosis Connection – or non-connection!
A study released in June, 2000, at the World Congress on Osteoporosis in Chicago, Illinois, found that taking thyroxine (i.e., Synthroid) does not increase the risk of osteoporosis. The research, presented by Dr. Martin Stenstrom of the University of Gothenburg in Sweden, studied more than 750 women who were taking prescribed thyroid medication for thyroid disease. Over an 18 month period, bone mineral density was measured, and compared to a control group who were not taking thyroid hormone. No differences were noted in bone mineral density between those taking the thyroid hormone, and the control group. An October, 1998 study reported on in the Journal of Gynecological Endocrinology found that levothyroxine suppressive therapy, if carefully carried out and monitored, has no significant effect on bone mass. ( Gynecol Endocrinol 1998 Oct;12(5):333-7, “Bone mineral density in premenopausal women receiving levothyroxine suppressive therapy.”).
The highly regarded Journal of Clinical Endocrinology and Metabolism found that even “suppressive,” levothyroxine therapy — prescribing medicine that lowers TSH levels to hyperthyroid levels below normal range — if carefully carried out and monitored, has no significant effect on bone metabolism or bone mass. ( J Clin Endocrinol Metab 1994 Apr;78(4):818-23, “Carefully monitored levothyroxine suppressive therapy is not associated with bone loss in premenopausal women.”)
A major thyroid-related journal, Thyroid, found that long-term levothyroxine therapy using suppressive doses has no significant adverse effects on bone. (Thyroid, 1995 Feb;5(1):13-7, “Suppressive doses of thyroxine do not accelerate age-related bone loss in late postmenopausal women.”)
Finally, in 1998, the Journal of Hormonal and Metabolic Research found that there was no difference in bone mineral density between thyroid patients and controls, and that the main factor in bone density and bone turnover is menopausal status. The researchers found that slightly suppressive levothyroxine doses constitute neither an actual risk factor for bone loss nor, consequently, for osteoporotic fractures. (Horm Metab Res 1995 Nov;27(11):503-7, “A slightly suppressive dose of L-thyroxine does not affect bone turnover and bone mineral density in pre- and postmenopausal women with nontoxic goitre.”)
On the other hand, there is some research that suggests that the osteoporosis risk may be a legitimate concern.
A May 2000 study in the European Journal of Endocrinology found that long-term treatment with levothyroxine to normal range TSH levels was associated with a slightly increased risk for osteoporotic fracture. (Eur J Endocrinol 2000 May;142(5):445-450, “The effect of long-term, non-suppressive levothyroxine treatment on quantitative ultrasonometry of bone in women.”).
And the Journal of Clinical Endocrinology and Metabolism has said that, although controversies exist on the possible adverse effect of T4 on bone mass, most studies reported bone loss in estrogen-deprived postmenopausal women taking suppressive doses of levothyroxine. Levothyroxine- suppressive therapy was associated with bone loss in postmenopausal women, however, it could be prevented by either calcium supplementation or intranasal calcitonin. ( J Clin Endocrinol Metab 1996 Mar;81(3):1232-6, “Prevention of bone loss induced by thyroxine suppressive therapy in postmenopausal women: the effect of calcium and calcitonin.”)
While the research is contradictory and sometimes confusing, the predominance of the evidence is pointing toward the conclusion that non-suppressive thyroid replacement does not dramatically increase the risk of osteoporosis, and that a key risk factor seems to be age and menopausal status. It does not seem logical for doctors to refuse to treat to lower-normal TSH level, or to provide supplemental and not excessive T3 treatment – both therapies which may help resolve major hypothyroidism symptoms for some patients- solely on the basis of concerns over osteoporosis. This is particularly true for patients who are pre-menopausal.
Here you will find information about the treatment of those who have been diagnosed with osteoporisis: