To the Editor.
—Dr Schneider and colleagues1 provide important new data on the long-term effect of thyroid hormone use on bone. Use of "suppressive" dose thyroid hormone was associated with significantly decreased bone mineral density (BMD) measured at multiple skeletal sites in the nearly 1000 women studied in a retirement community. Overall, for the 20% who were thyroid hormone users, multivariate-adjusted BMD was significantly lower at the midshaft radius, total hip, and lumbar spine sites, but the mean differences from nonusers were small in absolute number and amounted to 3.8%, 3.3%, and 3.2%, respectively (data from Schneider et al,1 Table 2). Schneider et al present evidence that thyroid hormone use is itself associated with osteopenia and not just the occurrence of prior endogenous hyperthyroidism. Yet controversy remains regarding the risk of bone loss from prescription thyroid hormone excess whether intentional as suppressive therapy or inadvertent. Furthermore, from other
Krakauer JC. Thyroid Hormone Use and Bone Mineral Density. JAMA. 1994;272(23):1822. doi:10.1001/jama.1994.03520230032029