Wayne State University School of Medicine, 5057 Woodward Avenue, Suite 6305, Detroit, MI 48202, USA.
Osteoporos Int. 2011 May;22(5):1377-88. doi: 10.1007/s00198-010-1349-4. Epub 2010 Aug 25.
Participants in the observational study of the Women's Health Initiative (WHI) were studied to determine if ethnic differences in femur geometry can help to explain differences in hip fracture rates. Structural differences in femurs of African and Mexican-American women appear to be consistent with lower rates of hip fractures vs. whites.
Ethnic origin has a major influence on hip fractures, but the underlying etiology is unknown. We evaluated ethnic differences in hip fracture rates among 159,579 postmenopausal participants in the WHI then compared femur bone mineral density (BMD) and geometry among a subset with dual X-ray absorptiometry (DXA) scans of the hip and total body.
The subset included 8,206 non-Hispanic whites, 1,476 African-American (AA), 704 Mexican-American (MA), and 130 Native Americans (NA). Femur geometry derived from hip DXA using hip-structure analysis (HSA) in whites was compared to minority groups after adjustment for age, height, weight, percent lean mass, neck-shaft angle and neck length, hormone use, chronic disease (e.g., diabetes, rheumatoid arthritis, cancer), bone active medications (e.g., corticosteroids, osteoporosis therapies), and clinical center.
Both AA and MA women suffered hip fractures at half the rate of whites while NA appeared to be similar to whites. The structural advantage among AA appears to be due to a slightly narrower femur that requires more bone tissue to achieve similar or lower section moduli (SM) vs. whites. This also underlies their higher BMD (reduces region area) and lower buckling ratios (buckling susceptibility). Both MA and NA women had similar advantages vs. whites at the intertrochanter region where cross-sectional area and SM were higher but with no differences at the neck. NA and MA had smaller bending moments vs. whites acting in a fall on the hip (not significant in small NA sample). Buckling ratios of MA did not differ from whites at any region although NA had 4% lower values at the IT region.
Differences in the geometry at the proximal femur are consistent with the lower hip fracture rates among AA and MA women compared to whites.
研究了参加妇女健康倡议（WHI）观察性研究的参与者，以确定股骨几何形状的种族差异是否有助于解释髋部骨折率的差异。非裔美国人和墨西哥裔美国女性的股骨结构差异似乎与髋部骨折发生率较低有关。
种族起源对髋部骨折有重大影响，但潜在病因尚不清楚。我们评估了 WHI 中 159579 名绝经后参与者的髋部骨折率的种族差异，然后比较了髋部和全身双能 X 线吸收法（DXA）扫描的亚组中股骨骨密度（BMD）和几何形状。
该亚组包括 8206 名非西班牙裔白人、1476 名非裔美国人（AA）、704 名墨西哥裔美国人（MA）和 130 名美国原住民（NA）。在调整年龄、身高、体重、瘦体重百分比、颈干角和颈长、激素使用、慢性疾病（如糖尿病、类风湿性关节炎、癌症）、骨活性药物（如皮质类固醇、骨质疏松症治疗）和临床中心后，使用髋关节结构分析（HSA）从髋部 DXA 中得出的股骨几何形状与少数族裔群体进行比较。
AA 和 MA 女性的髋部骨折发生率均为白人的一半，而 NA 似乎与白人相似。AA 中的结构优势似乎是由于股骨稍窄，需要更多的骨骼组织才能达到相似或较低的截面模数（SM），而白人则需要较少的骨骼组织。这也解释了他们较高的 BMD（减少区域面积）和较低的屈曲比（屈曲易感性）。与白人相比，MA 和 NA 女性在股骨转子间区域具有相似的优势，因为横截面积和 SM 较高，但在颈部没有差异。NA 和 MA 对髋关节的跌倒作用较小的弯曲力矩（在小的 NA 样本中不显著）。MA 的屈曲比在任何区域都与白人没有差异，尽管 NA 在 IT 区域的数值低 4%。
股骨近端几何形状的差异与 AA 和 MA 女性髋部骨折发生率低于白人一致。
