ABSTRACT
It is well established that BMD and an increased rate of bone resorption are strong, independent risk factors for fractures. This was also confirmed in the study of Eastell et al, where femoral neck and lumbar spine BMD, NTX and CTX were signifi cantly related to the subsequent risk of vertebral fractures at both 1 and 3 years. The same relationship was also observed for the risk of new non-vertebral fractures at
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3 years for BMD (P < 0.001) and NTX (P = 0.040), but not for CTX (0.342). There is disagreement, however, regarding the relative contribution of changes in BMD to the antifracture efficacy of antiresorptive agents. This disagreement has stemmed from observations in clinical trials of antiresorptive agents showing reductions in the risk of vertebral fractures of a similar magnitude by agents with a small or a larger effect
NTX change (%)
CTX change (%)
Fig. 13.1 Relationship between percentage change in bone resorption markers and the incidence of new vertebral fractures. The placebo group is represented by the broken line and the risedronate 5 mg group by the solid line. All patients received calcium supplementation (1000 mg/day) and vitamin D (if levels were low). Source: Eastell et al. (2003).
