Section for Health Promotion, Department of Health and Medical Care, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka-machi, Obu, Aichi, 474-8511, Japan.
Aging Clin Exp Res. 2010 Oct-Dec;22(5-6):427-32. doi: 10.1007/BF03337738. Epub 2009 Dec 18.
Many older people fall when they perform tasks which require increased attention. The aim of this study was to determine differences in reaction times, during simple-, dual- and triple-task conditions requiring differing levels of motor coordination, balance control and cognitive attention, between groups of fallers and non-fallers in community-dwelling older individuals.
The study involved the recruitment of 87 older individuals living at home, 57 women and 30 men aged 75 to 91 years. Reaction times, measured by pushing a handheld button as quickly as possible in response to a visual stimulus, were measured in four conditions: 1) quiet standing (simple-task); 2) counting backward during quiet standing (dual-task with cognitive demand); 3) stepping in place (dual-task with balance demand); and 4) counting backward while stepping in place (triple-task with cognitive and balance demands).
Twenty-nine (33.3%) participants had fallen at least once during the past year. There were no statistically significant differences in reaction times between non-fallers and fallers during any of the tasks. Reaction times were significantly longer during the dual- and triple-tasks compared with the simple-task conditions in both groups. The ratio between reaction times during dual-tasks with balance demands (stepping in place) and those in the simple-task condition were significantly related to a history of falls and showed the highest odds ratio (OR 3.16, 95% CI 1.06- 9.45, p=0.04).
Relative changes in reaction times during a dual-task with balance demands were related to a history of falls in community-dwelling older individuals. Reaction times in dual-task conditions with a balance demand were more sensitive to past falls than those during a dual-task with cognitive demands.
许多老年人在执行需要增加注意力的任务时会摔倒。本研究的目的是确定在社区居住的老年人中，跌倒组和非跌倒组在简单任务、双重任务和三重任务条件下的反应时间差异，这些任务需要不同程度的运动协调、平衡控制和认知注意力。
本研究招募了 87 名居住在家的老年人，其中 57 名女性，30 名男性，年龄在 75 岁至 91 岁之间。通过按下手持按钮来测量反应时间，反应时间是对视觉刺激做出尽可能快的反应，在以下四种条件下进行测量：1）安静站立（简单任务）；2）安静站立时倒数（认知需求的双重任务）；3）原地踏步（平衡需求的双重任务）；4）原地踏步时倒数（认知和平衡需求的三重任务）。
29 名（33.3%）参与者在过去一年中至少跌倒过一次。在任何任务中，非跌倒者和跌倒者的反应时间均无统计学差异。在双重任务和三重任务中，反应时间明显长于简单任务条件。两组的双重任务与平衡需求（原地踏步）的反应时间与简单任务条件的反应时间之比与跌倒史显著相关，且具有最高的优势比（OR 3.16，95%CI 1.06-9.45，p=0.04）。
在平衡需求的双重任务中，反应时间的相对变化与社区居住的老年人的跌倒史有关。具有平衡需求的双重任务条件下的反应时间比具有认知需求的双重任务条件下的反应时间更能反映过去的跌倒。
