Osteoporosis Center, Internal Medicine Ward, Hadassah Medical Center, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
Osteoporosis Prevention and Treatment Center, Division of Endocrinology, Beth Israel Deaconess Medical Center, Boston, MA, USA.
J Clin Densitom. 2024 Oct-Dec;27(4):101520. doi: 10.1016/j.jocd.2024.101520. Epub 2024 Aug 13.
Only change in bone mineral density (BMD) on repeat DXA that exceeds the 95% least significant change (LSC) should be considered clinically meaningful. Frequently lumbar spine DXA must be reported after omitting vertebrae with localized structural artifact, which reduces measurement precision. Previous reports have raised concerns of higher least significant change (LSC) when spine BMD is based on non-contiguous rather than contiguous vertebrae. The current study was performed to compare lumbar spine LSC and BMD response to intervening anti-osteoporosis medication use from non-contiguous versus contiguous vertebrae.
LSCs for lumbar spine DXA based on L1-L4 and all combinations of non-contiguous and contiguous vertebrae were calculated using 879 scan-pairs from the Manitoba BMD Program. We compared BMD change from these regions, overall and in relation to intervening anti-osteoporosis medication use, in 11,722 patients who had 2 DXA examinations.
LSCs were slightly greater when calculated from combinations of fewer than 4 vertebrae, but there was no meaningful difference between contiguous versus non-contiguous vertebrae. There were consistently high correlations between lumbar spine BMD change from L1-L4 and all combinations of continuous and non-contiguous vertebrae (all Pearson r≥ 0.9, p<0.001). Percentage changes in spine BMD and the fraction with treatment-concordant change exceeding the LSC were similar using contiguous or non-contiguous vertebrae.
Lumbar spine BMD change can be assessed from 2 or 3 non-contiguous vertebrae when clinically necessary, and precision in such cases is similar to using contiguous vertebrae. Non-contiguous vertebrae can detect treatment-concordant changes similar in spine BMD to contiguous vertebrae.
只有在重复 DXA 中超过 95%最小显著变化 (LSC) 的骨密度 (BMD) 变化才应被认为具有临床意义。通常情况下，在腰椎 DXA 报告中必须排除具有局部结构伪影的椎体，这会降低测量精度。先前的报告表明，当脊柱 BMD 基于不连续而不是连续的椎体时，LSC 会更高。本研究旨在比较基于不连续而非连续椎体的腰椎 LSC 和 BMD 对干预性抗骨质疏松药物使用的反应。
使用曼尼托巴省 BMD 计划的 879 对扫描对，计算 L1-L4 和所有非连续与连续椎体组合的腰椎 DXA 的 LSC。我们比较了这些区域的 BMD 变化，总体变化以及与干预性抗骨质疏松药物使用的关系，在 11722 名接受 2 次 DXA 检查的患者中。
当从少于 4 个椎体的组合中计算时，LSC 会略大，但连续与非连续椎体之间没有显著差异。L1-L4 与所有连续和非连续椎体组合的腰椎 BMD 变化之间始终存在高度相关性（所有 Pearson r≥0.9，p<0.001）。使用连续或非连续椎体时，脊柱 BMD 的百分比变化和治疗一致变化超过 LSC 的部分相似。
在临床需要时，可以从 2 或 3 个非连续椎体评估腰椎 BMD 变化，在这种情况下，精度与使用连续椎体相似。非连续椎体可以检测到与连续椎体相似的脊柱 BMD 治疗一致变化。
