Brauer S G, Burns Y R, Galley P
Department of Physiotherapy, University of Queensland, St. Lucia, Australia.
J Gerontol A Biol Sci Med Sci. 2000 Aug;55(8):M469-76. doi: 10.1093/gerona/55.8.m469.
The identification of specific risk factors for falls in community-dwelling elderly persons is required to detect early changes and permit a preventative approach to management. This study determines the ability of various laboratory measures and clinical tests of postural stability to prospectively predict fallers in community-dwelling elderly women.
One hundred elderly women (65-86 years, mean age 73 +/- 5 years) performed a reaction-time step task, a limits of stability, and a quiet stance balance task. Postural muscle timing and movement speed were recorded during the step task. Center of pressure (COP) motion was recorded in quiet stance and at the limits of stability. Four common clinical balance tests were performed, and balance confidence, medical and activity history questionnaires were completed. Subjects were followed up regularly for a 6-month period following testing to determine the frequency and characteristics of any falls that occurred. Predictive capabilities of the balance measures to determine fallers were determined through logistic regression models.
The clinical balance tests investigated were not able to predict fallers in this community-dwelling elderly population. A combination of variables from the laboratory tasks provided the best overall prediction rate (77%) of fallers (sensitivity 51%) and nonfallers (specificity 91%) from laboratory measures. Of these, step movement time and gluteus medius onset times were the factors best able to predict fallers. Alone, measures of COP motion in quiet stance and at the limits of stability had a poor ability to predict fallers, although they could correctly identify most nonfallers. Prediction was not significantly improved when clinical balance test results were added to the most predictive laboratory measures.
Not all older adults with a reduction in balance ability reported a fall over a 6-month period. Of those who did, a combination of measures reflective of different aspects of mediolateral postural stability during a rapid step task, quiet stance, and movement to the limits of stability were best able to predict faller status, with nonfallers better predicted than fallers. These results emphasize the importance of the multifactorial nature of falls in the community-dwelling elderly population in that the clinical and laboratory measures did not predict a high proportion of fallers.
需要确定社区居住老年人跌倒的特定风险因素，以便检测早期变化并采取预防性管理方法。本研究确定各种实验室测量和姿势稳定性临床测试对社区居住老年女性跌倒者进行前瞻性预测的能力。
100名老年女性（65 - 86岁，平均年龄73±5岁）进行了反应时间步任务、稳定性极限测试和安静站立平衡任务。在步任务期间记录姿势肌肉时间和运动速度。在安静站立和稳定性极限时记录压力中心（COP）运动。进行了四项常见的临床平衡测试，并完成了平衡信心、医疗和活动历史问卷。测试后对受试者进行为期6个月的定期随访，以确定发生的任何跌倒的频率和特征。通过逻辑回归模型确定平衡测量对确定跌倒者的预测能力。
所研究的临床平衡测试无法预测该社区居住老年人群中的跌倒者。实验室任务中的变量组合提供了来自实验室测量的跌倒者（敏感性51%）和非跌倒者（特异性91%）的最佳总体预测率（77%）。其中，步运动时间和臀中肌起始时间是最能预测跌倒者的因素。单独来看，安静站立和稳定性极限时的COP运动测量预测跌倒者的能力较差，尽管它们可以正确识别大多数非跌倒者。当将临床平衡测试结果添加到最具预测性的实验室测量中时，预测并未显著改善。
并非所有平衡能力下降的老年人在6个月内都报告跌倒。在那些跌倒的人中，反映快速步任务、安静站立和运动到稳定性极限期间中外侧姿势稳定性不同方面的测量组合最能预测跌倒状态，非跌倒者比跌倒者预测得更好。这些结果强调了社区居住老年人群跌倒多因素性质的重要性，因为临床和实验室测量并未预测出高比例的跌倒者。
