Adding VFA to DXA Identifies Fracture Risk in a Way Not Duplicated by Other Measures

Abstract

Published studies have demonstrated that adding vertebral fracture assessment (VFA) to dual-energy X-ray absorptiometry (DXA) identifies more patients with increased fracture risk than DXA alone. But who needs VFA? This study attempts to determine if some test other than VFA could duplicate the additional information obtained by performing VFA on all first-time patients. This study looked at the Fracture Risk Assessment Tool (FRAX), height loss, age, documented back pain, and nonvertebral fragility fractures. VFA was performed on 1,259 (all) DXA patients at their first visit from March 2010 through September 2013. All DXA and VFA results were read by the same International Society for Clinical Densitometry-certified clinician. By DXA alone, 44% were osteoporosis. Adding VFA increased clinical osteoporosis by 36% of the original total patients. Eighty-three "normal bone mineral density" patients were changed to clinical osteoporosis. FRAX identified 53% of the patients with diagnosis changes. Historical height loss was not reliable. Increasing age correlated only weakly with clinical osteoporosis. These are modest numbers from a nonacademic referral practice and may not be typical of other populations. Thirty-six percent of our patients were misclassified by DXA alone, with fragility fractures already taken into account for T-scores of -1.5 and lower. FRAX, height loss, age, back pain, and fragility fractures all failed to identify many of the patients identified by VFA. Seeing the lateral spine images obtained by VFA influenced patients and families. VFA on all first-time patients should be reconsidered. BMD = bone mineral density DXA = dual-energy X-ray absorptiometry FRAX = Fracture Risk Assessment Tool HL = height loss ISCD = International Society for Clinical Densitometry VF = vertebral fracture VFA = vertebral fracture assessment.