Jergas M, Breitenseher M, Glüer C C, Yu W, Genant H K
Department of Radiology, University of California San Francisco, USA.
J Bone Miner Res. 1995 Jul;10(7):1101-10. doi: 10.1002/jbmr.5650100715.
To determine whether estimates of volumetric bone density from projectional scans of the lumbar spine have weaker associations with height and weight and stronger associations with prevalent vertebral fractures than standard projectional bone mineral density (BMD) and bone mineral content (BMC), we obtained posteroanterior (PA) dual X-ray absorptiometry (DXA), lateral supine DXA (Hologic QDR 2000), and quantitative computed tomography (QCT, GE 9800 scanner) in 260 postmenopausal women enrolled in two trials of treatment for osteoporosis. In 223 women, all vertebral levels, i.e., L2-L4 in the DXA scan and L1-L3 in the QCT scan, could be evaluated. Fifty-five women were diagnosed as having at least one mild fracture (age 67.9 +/- 6.5 years) and 168 women did not have any fractures (age 62.3 +/- 6.9 years). We derived three estimates of "volumetric bone density" from PA DXA (BMAD, BMAD*, and BMD*) and three from paired PA and lateral DXA (WA BMD, WA BMDHol, and eVBMD). While PA BMC and PA BMD were significantly correlated with height (r = 0.49 and r = 0.28) or weight (r = 0.38 and r = 0.37), QCT and the volumetric bone density estimates from paired PA and lateral scans were not (r = -0.083 to r = 0.050). BMAD, BMAD*, and BMD* correlated with weight but not height. The associations with vertebral fracture were stronger for QCT (odds ratio [QR] = 3.17; 95% confidence interval [CI] = 1.90-5.27), eVBMD (OR = 2.87; CI 1.80-4.57), WA BMDHol (OR = 2.86; CI 1.80-4.55) and WA-BMD (OR = 2.77; CI 1.75-4.39) than for BMAD*/BMD* (OR = 2.03; CI 1.32-3.12), BMAD (OR = 1.68; CI 1.14-2.48), lateral BMD (OR = 1.88; CI 1.28-2.77), standard PA BMD (OR = 1.47; CI 1.02-2.13) or PA BMC (OR = 1.22; CI 0.86-1.74). The areas under the receiver operating characteristic (ROC) curves for QCT and all estimates of volumetric BMD were significantly higher compared with standard PA BMD and PA BMC. We conclude that, like QCT, estimates of volumetric bone density from paired PA and lateral scans are unaffected by height and weight and are more strongly associated with vertebral fracture than standard PA BMD or BMC, or estimates of volumetric density that are solely based on PA DXA scans.
为了确定腰椎投影扫描所得的体积骨密度估计值与身高和体重的关联是否比标准投影骨密度（BMD）和骨矿物质含量（BMC）更弱，而与现患椎体骨折的关联更强，我们对260名参加两项骨质疏松症治疗试验的绝经后女性进行了后前位（PA）双能X线吸收法（DXA）、仰卧位侧位DXA（Hologic QDR 2000）以及定量计算机断层扫描（QCT，GE 9800扫描仪）检查。在223名女性中，所有椎体水平，即DXA扫描中的L2 - L4和QCT扫描中的L1 - L3，均可进行评估。55名女性被诊断为至少有一处轻度骨折（年龄67.9±6.5岁），168名女性无任何骨折（年龄62.3±6.9岁）。我们从PA DXA得出了三种“体积骨密度”估计值（BMAD、BMAD和BMD），并从配对的PA和侧位DXA得出了三种（WA BMD、WA BMDHol和eVBMD）。虽然PA BMC和PA BMD与身高（r = 0.49和r = 0.28）或体重（r = 0.38和r = 0.37）显著相关，但QCT以及配对的PA和侧位扫描所得的体积骨密度估计值并非如此（r = -0.083至r = 0.050）。BMAD、BMAD和BMD与体重相关，但与身高无关。与椎体骨折的关联在QCT（比值比[OR] = 3.17；95%置信区间[CI] = 1.90 - 5.27）、eVBMD（OR = 2.87；CI 1.80 - 4.57）、WA BMDHol（OR = 2.86；CI 1.80 - 4.55）和WA - BMD（OR = 2.77；CI 1.75 - 4.39）方面比在BMAD*/BMD*（OR = 2.03；CI 1.32 - 3.12）、BMAD（OR = 1.68；CI 1.14 - 2.48）、侧位BMD（OR = 1.88；CI 1.28 - 2.77）、标准PA BMD（OR = 1.47；CI 1.02 - 2.13）或PA BMC（OR = 1.22；CI 0.86 - 1.74）方面更强。与标准PA BMD和PA BMC相比，QCT以及所有体积BMD估计值的受试者工作特征（ROC）曲线下面积显著更高。我们得出结论，与QCT一样，配对的PA和侧位扫描所得的体积骨密度估计值不受身高和体重影响，并且与椎体骨折的关联比标准PA BMD或BMC，或仅基于PA DXA扫描的体积密度估计值更强。
