Abstract
Liu-Ambrose T, Ahamed Y, Graf P, Feldman F, Robinovitch SN. Older fallers with poor
working memory overestimate their postural limits.
Objective
To compare the accuracy of perceived postural limits between older fallers with good
working memory and those with poor working memory.
Design
Cross-sectional study.
Setting
Research laboratory.
Participants
Thirty-three community-dwelling older adults with a history of falls.
Interventions
Not applicable.
Main Outcome Measures
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.
Results
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 R2 change of 18.2% and significantly improved the regression model (F1,26 change, 7.45; P=.01).
Conclusions
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.
Key Words
List of Abbreviations:
ABC (Activities-specific Balance Confidence), BDI (Beck Depression Inventory), MMSE (Mini-Mental State Examination), TUG (Timed Up & Go)To read this article in full you will need to make a payment
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Article info
Footnotes
Supported in part by the Canadian Institutes of Health Research (career scientist award) and the Michael Smith Foundation for Health Research (career scientist awards).
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated.
Reprints are not available from the authors.
Identification
Copyright
© 2008 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
