The Effect of Abdominal Anatomy on the Measurement of Bone Mineral Density With Dual-Energy X-Ray Absorptiometry.

OBJECTIVE: This study aimed to assess the effects of abdominal fat content and anatomical changes on the measurement of bone mineral density using dual-energy X-ray absorptiometry (DXA). MATERIALS AND METHODS: The bone mineral density measurements were performed with quantitative computed tomography for patients who underwent DXA and abdominal CT on the same day. The effects of abdominal fat content and anatomic changes on the results of DXA were assessed. RESULTS: Of the 43 patients, 88.3% were women, 11.7% were men, and the mean age was 55.6 years (range, 32-72). There was a significant relationship between the error in the measurement of T-scores with DXA and osteophytic new bone formation (P = 0.011). There were significant relationships between the error in detecting osteoporosis with DXA and osteophytic new bone formation, facet joint degeneration, and aortic calcification (P < 0.05). CONCLUSIONS: Abdominal fat content does not significantly affect T-scores. However, DXA can give false-negative results in detecting osteoporosis, especially in patients with osteophyte new bone formation, facet joint degeneration, and aortic calcifications, all conditions primarily in elderly patients. In these cases, it is more appropriate to use quantitative computed tomography instead of DXA.