Enhanced prediction of fracture risk combining vertebral fracture status and BMD
- 606 Downloads
Prevalent vertebral fractures are associated with increased fracture risk, but the magnitude of this effect across a range of BMD T-scores has not been quantified. In this analysis, for any given BMD T-score, incident fracture risk varied up to twelve fold when information regarding prevalent radiographic vertebral fracture status was considered.
Clinical fracture risk evaluation of older women usually includes assessment of bone mineral density (BMD) but often not vertebral fracture status. In this analysis, we quantified the impact of vertebral fracture burden on two year fracture risk across a range of BMD T-scores.
Data were from 2,651 postmenopausal women who were assigned to the placebo groups of the Fracture Prevention Trial (median observation 21 months) and the Multiple Outcomes of Raloxifene Evaluation Trial (MORE; observation 2 years). Using the Genant visual semiquantitative criteria, we defined prevalent vertebral fracture status as: a) presence or absence of fracture; b) fracture number; c) maximum semi-quantitative (SQ) score (normal=0, mild fracture=1, moderate fracture=2, severe fracture=3); and d) spinal deformity index (SDI) score (sum of SQ scores of T4 to L4 vertebrae). Incident fractures over two years were identified via lateral spine radiographs and outside the spine by questioning of patients and review of radiographs or radiographic reports.
Femoral neck BMD T-score provided significant information regarding fracture risk. Across the range of T-scores, vertebral fracture status provided additional prognostic information. The risk increased with increasing number and severity of prevalent vertebral fractures and SDI, a summary measure of spine fracture burden. Across a range of BMD values, prevalent spine fracture burden as assessed by SDI increased the risk of incident vertebral fractures by up to 12-fold, nonvertebral fractures by about twofold, and any fractures by up to sevenfold.
These findings indicate that at any given BMD T-score, the risk of incident vertebral, non-vertebral, and any fracture depended heavily on prevalent radiographic vertebral fracture status. Assessment of vertebral fracture status, in addition to BMD, provides practical and relevant clinical information to aid in predicting fracture risk in postmenopausal women.
KeywordsNon-vertebral fracture Osteoporosis Semiquantitative assessment Spine deformity index Spine radiograph Vertebral fracture Vertebral fracture assessment
- 2.Ettinger B, Black DM, Mitlak BH et al (1999) Reduction of vertebral fracture risk in postmenopausal women with osteoporosis treated with raloxifene: results from a 3-year randomized clinical trial. Multiple Outcomes of Raloxifene Evaluation (MORE) Investigators. JAMA 282(7):637–645PubMedCrossRefGoogle Scholar
- 7.Ross PD, Davis JW, Epstein RS, Wasnich RD (1999) Pre-existing fractures and bone mass predict vertebral fracture incidence in women. Ann Intern Med 114(11):919–923Google Scholar
- 16.Harris ST, Watts NB, Genant HK et al (1999) Effects of risedronate treatment on vertebral and nonvertebral fractures in women with postmenopausal osteoporosis: a randomized controlled trial. Vertebral Efficacy With Risedronate Therapy (VERT) Study Group. JAMA 282(14):1344–1352PubMedCrossRefGoogle Scholar
- 21.Genant HK, Delmas PD, Chen P, Yiang Y, Eriksen EF, Dalsky GP, Marcus R, San Martin J. Severity of vertebral fracture reflects deterioration of bone microarchitecture. Osteoporosis International (in press)Google Scholar
- 24.Faulkner KG (2001) Clinical use of bone densitometry. In: Marcus R, Feldman D, Kelsey J (eds) Osteoporosis. Academic Press, San Diego, CA, USA, pp 433–458Google Scholar
- 29.Wu C, Genant H, von Ingersleben G et al (2004) Validation of lateral DXA imaging for assessment of vertebral fractures. J Bone Miner Res 19(suppl 1):S295Google Scholar