Joint Doctoral Program in Public Health (Epidemiology), San Diego State University/University of California, San Diego, San Diego, CA, USA.
Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA, USA.
Osteoporos Int. 2020 Jun;31(6):1097-1104. doi: 10.1007/s00198-019-05155-8. Epub 2020 Feb 10.
Hyperkyhosis is thought to be a fall risk factor in older adults. This large study of older men found that fall risk increased with greater kyphosis measured with the blocks method, but did not find an association between kyphosis and falls when measured by the commonly used the Cobb angle method.
Research suggests an association between hyperkyphosis and falls in community-dwelling older adults, though this has not been investigated within large, population-based studies. This study sought to determine whether two measures of kyphosis prospectively predict fall risk over 3 years among older men.
Within the Osteoporotic Fractures in Men Study (MrOS), we conducted two 3-year prospective studies of 2346 and 2928 men. The first group had kyphosis measured by the Cobb angle at visit 1, while the second group had kyphosis assessed with the blocks method at visit 3; both groups then self-reported falls tri-annually for 3 years. Poisson regression with GEE was used to obtain relative risks (RR) of falls.
The fall rates over 3 years were 651/1000 person-years among the visit 1 sample (mean age 74 ± 6 years) and 839/1000 person-years among the visit 3 sample (mean age 79 ± 5 years). In adjusted models of the visit 3 sample, the risk of falls was increased by 12% for each standard deviation increase (1.4 blocks) in the number of blocks required to achieve a neutral head and neck position (RR = 1.12, 95% CI = 1.06, 1.18). The Cobb angle was not associated with falls in the visit 1 sample.
Although the Cobb angle did not predict falls in community-dwelling older men over 3 years, the blocks method of measuring kyphosis was predictive of falls in this population. This difference could be due to the Cobb angle's focus on thoracic kyphosis, whereas the blocks method may additionally capture abnormal cervical spine curvature.
人们认为过度后凸是老年人跌倒的一个风险因素。这项针对老年男性的大型研究发现，使用垫块法测量的后凸角度越大，跌倒风险越高，但使用常用的 Cobb 角法测量后凸与跌倒之间没有关联。
研究表明，社区居住的老年人中存在后凸与跌倒之间的关联，但这尚未在大型人群研究中进行调查。本研究旨在确定两种后凸测量方法是否能前瞻性地预测老年男性 3 年内的跌倒风险。
在男性骨质疏松性骨折研究（MrOS）中，我们进行了两项为期 3 年的前瞻性研究，共有 2346 名和 2928 名男性参与。第一组在第一次就诊时使用 Cobb 角测量后凸，第二组在第三次就诊时使用垫块法评估后凸；两组随后每 3 年自我报告 3 次跌倒。使用广义估计方程（GEE）的泊松回归来获得跌倒的相对风险（RR）。
在为期 3 年的随访中，第一次就诊样本的跌倒发生率为 651/1000 人年（平均年龄 74±6 岁），第三次就诊样本的跌倒发生率为 839/1000 人年（平均年龄 79±5 岁）。在调整后的第三次就诊样本模型中，每增加一个标准差（1.4 个垫块），达到中立头颈部位置所需的垫块数量增加 12%，跌倒风险增加（RR=1.12，95%CI=1.06，1.18）。Cobb 角与第一次就诊样本的跌倒无关。
虽然 Cobb 角在 3 年内不能预测社区居住的老年男性的跌倒，但测量后凸的垫块法在该人群中预测跌倒。这种差异可能是由于 Cobb 角主要关注胸段后凸，而垫块法可能还额外捕获了异常的颈椎曲度。
