Department of Radiology, University of Colorado Anschutz Medical Campus, 12700 E 19th Ave, Mail Stop C278, Room 1208, Aurora, CO, 80045, USA.
Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA.
Osteoporos Int. 2022 Aug;33(8):1739-1753. doi: 10.1007/s00198-022-06405-y. Epub 2022 Apr 27.
People living with HIV (PLWH) have increased risk of osteoporosis and fractures. We assessed the proximal femur of PLWH and age-matched seronegative controls using quantitative computed tomography and magnetic resonance imaging. Results suggest that the trabecular compartment is compromised at fracture-prone regions in the proximal femur of PLWH.
People living with HIV (PLWH) have increased risk of osteoporosis and fractures. However, studies assessing the main determinants of bone strength in the proximal femur exclude this vulnerable population. We assessed the proximal femur of 40 PLWH and 26 age-matched seronegative controls using quantitative computed tomography and magnetic resonance imaging.
We examined cortical volumetric bone mineral density (Ct.vBMD), trabecular vBMD (Tb.vBMD), cortical thickness (Ct.Th), bone marrow adiposity (BMA), and trabecular number, separation, and bone volume fraction. Parametric comparisons between the two groups were made for the femoral head, femoral neck, trochanter, and total hip using linear regression adjusting for several covariates, including metrics of body composition. In addition, we investigated the associations of BMA with Tb.vBMD and trabecular microarchitecture with Spearman's rank partial correlations.
PLWH had lower Tb.vBMD and deteriorated trabecular microarchitecture in the femoral neck, trochanter and total hip, and elevated BMA in the femoral head, femoral neck, and total hip. Ct.vBMD and Ct.Th were not significantly different between the two groups. BMA was significantly associated with lower Tb.vBMD and deteriorated trabecular microarchitecture in both groups albeit at different femoral regions.
Our findings suggest that the trabecular, and not the cortical, compartment is compromised in the proximal femur of PLWH. The observed impairments in fracture-prone regions in PLWH indicate lower femoral strength and suggest higher fracture risk. The inverse associations of BMA with trabecular bone density and microarchitecture quality agree with findings at other anatomic sites and in other populations, suggesting that excess BMA possibly due to a switch from the osteoblast to the adipocyte lineage may be implicated in the pathogenesis of bone fragility at the femur in PLWH.
本研究旨在使用定量计算机断层扫描（QCT）和磁共振成像（MRI）评估 HIV 感染者（PLWH）和年龄匹配的血清阴性对照者的股骨近端。
我们评估了 40 名 PLWH 和 26 名年龄匹配的血清阴性对照者的股骨近端，使用 QCT 和 MRI 评估了皮质容积骨矿物质密度（Ct.vBMD）、松质骨 vBMD（Tb.vBMD）、皮质厚度（Ct.Th）、骨髓脂肪含量（BMA）和小梁数量、分离和骨体积分数。使用线性回归对两组进行参数比较，调整了包括身体成分指标在内的几个协变量。此外，我们还通过 Spearman 秩相关分析研究了 BMA 与 Tb.vBMD 的相关性以及小梁微结构与 BMA 的相关性。
PLWH 的股骨颈、转子间区和全髋的 Tb.vBMD 较低，小梁微结构恶化，BMA 升高；股骨颈、转子间区和全髋的 Tb.vBMD 和皮质厚度无显著差异。BMA 与两组的 Tb.vBMD 呈显著负相关，与小梁微结构恶化呈显著正相关，但在不同的股骨区域。
我们的研究结果表明，PLWH 的股骨近端的松质骨而不是皮质骨受损。在 PLWH 中，在易骨折区域观察到的损伤表明股骨强度较低，提示骨折风险较高。BMA 与松质骨密度和微结构质量呈负相关，这与其他解剖部位和其他人群的研究结果一致，提示过多的 BMA 可能由于成骨细胞向脂肪细胞系的转变，可能与 PLWH 股骨脆性的发病机制有关。
