Prediction of fracture from low bone mineral density measurements overestimates risk

There is a well-established relationship between bone mineral density (BMD) and fracture risk. Estimates of the relative risk of fracture from BMD hav e been derived mainly from short-term studies in which the correlation betw een BMD at assessment and BMD in later life ranged from 0.8 to 0.9. Because individuals lose bone mineral at different rates throughout later life, th e long-term predictive value of low BMD is likely to decrease progressively with time. This article examines and formalizes the relationship between c urrent BMD, correlation coefficients, and long-term risk. The loss of predi ctive value has important implications for early assessment and supports th e view that measurements should be optimally targeted at the time intervent ions are contemplated and, when necessary, repeated in later life. (Bone 26 :387-391; 2000) (C) 2000 by Elsevier Science Inc. All rights reserved.