Liu-Ambrose Teresa, Ahamed Yasmin, Graf Peter, Feldman Fabio, Robinovitch Stephen N
Centre for Hip Health, Vancouver Coastal Health Research Institute, University of British Columbia, Vancouver, BC, Canada.
Arch Phys Med Rehabil. 2008 Jul;89(7):1335-40. doi: 10.1016/j.apmr.2007.11.052.
To compare the accuracy of perceived postural limits between older fallers with good working memory and those with poor working memory.
Cross-sectional study.
Research laboratory.
Thirty-three community-dwelling older adults with a history of falls.
Not applicable.
We measured the accuracy of perceived postural limits by using the perceived reach test in 33 fallers. The difference between the verbal digits forward test score and the verbal digits backward test score was used to provide an index of the central executive component of working memory. Participants were then allocated into 2 groups: (1) good working memory or (2) poor working memory. Comparisons of group characteristics and scores were undertaken by using Student independent-sample t tests for differences in means between those with good working memory and those with poor memory. One hierarchical linear regression model was constructed to determine the independent association of the central executive component of working memory with the accuracy of older fallers' perceived reach capacity.
There was a significant difference in the mean percentage error in perceived reach between older fallers with good working memory and those with poor working memory (P=.01). The verbal digit span difference score was independently associated with the percentage error in perceived reach. The verbal digit span difference score resulted in an R(2) change of 18.2% and significantly improved the regression model (F(1,26) change, 7.45; P=.01).
Our novel results suggest that impaired executive functioning may increase falls risk by impairing older adults' judgment in motor planning for daily activities. However, future studies with larger sample sizes are needed to confirm our current results.
比较工作记忆良好的老年跌倒者与工作记忆较差的老年跌倒者在感知姿势极限方面的准确性。
横断面研究。
研究实验室。
33名有跌倒史的社区居住老年人。
不适用。
我们通过对33名跌倒者进行感知伸展测试来测量感知姿势极限的准确性。用言语数字顺背测验分数与言语数字倒背测验分数之间的差异作为工作记忆中央执行成分的指标。然后将参与者分为两组：（1）工作记忆良好组或（2）工作记忆较差组。采用学生独立样本t检验对工作记忆良好者和记忆较差者的组间特征和分数差异进行比较。构建一个分层线性回归模型，以确定工作记忆中央执行成分与老年跌倒者感知伸展能力准确性之间的独立关联。
工作记忆良好的老年跌倒者与工作记忆较差的老年跌倒者在感知伸展的平均百分比误差上存在显著差异（P = 0.01）。言语数字广度差异分数与感知伸展的百分比误差独立相关。言语数字广度差异分数使R²变化了18.2%，并显著改善了回归模型（F(1,26)变化，7.45；P = 0.01）。
我们的新结果表明，执行功能受损可能会损害老年人在日常活动运动计划中的判断力，从而增加跌倒风险。然而，需要未来更大样本量的研究来证实我们目前的结果。
