Date Published: October 18, 2017
Publisher: Public Library of Science
Author(s): Jason L. Rucker, Joan M. McDowd, Jonathan D. Mahnken, Jeffrey M. Burns, Carla H. Sabus, Amanda J. Britton-Carpenter, Nora B. Utech, Patricia M. Kluding, David J Clark.
Deficits in the ability to multitask contribute to gait abnormalities and falls in many at-risk populations. However, it is unclear whether older adults with type 2 diabetes mellitus (DM) also demonstrate impairments in multitasking. The purpose of this study was to compare multitasking performance in cognitively intact older adults with and without DM and explore its relationship to measures of gait and functional ability.
We performed a cross-sectional analysis of 40 individuals aged 60 and older with type 2 DM and a matched group of 40 cognitively intact older adults without DM. Multitasking was examined via the ambulatory Walking and Remembering Test (WART) and seated Pursuit Rotor Test (PRT). Self-selected normal and fast walking speed and stride length variability were quantitatively measured, and self-reported functional ability was assessed via the Late Life Function and Disability Index (LLFDI).
Participants with DM walked slower and took more steps off path when multitasking during the WART. No between-group differences in multitasking performance were observed on the PRT. Multitasking performance demonstrated little correlation with gait and functional ability in either group.
Older adults with DM appear to perform poorly on an ambulatory measure of multitasking. However, we analyzed a relatively small, homogenous sample of older adults with and without type 2 DM and factors such as peripheral neuropathy and the use of multiple comparisons complicate interpretation of the data. Future research should explore the interactions between multitasking and safety, fall risk, and function in this vulnerable population. Clinicians should recognize that an array of factors may contribute to gait and physical dysfunction in older adults with type 2 diabetes, and be prepared to assess and intervene appropriately.
Dividing attention between simultaneous activities in order to multitask is a highly functional human behavior. This complex balancing of attentional resources is often described as an executive function  and can be elicited by dual-task paradigms that examine the changes in performance that occur when multiple tasks are undertaken simultaneously . Such dual-task studies suggest that an impaired ability to multitask may influence gait and function in a number of high risk groups [3–5], including the rapidly increasing population of older adults with type 2 diabetes [6, 7].
This study is one of relatively few that have attempted to characterize multitasking abilities in older adults with type 2 diabetes. We observed that these individuals performed comparably to their counterparts without diabetes on a seated measure of multitasking involving upper extremity function, the PRT. However, they fared worse on an ambulatory measure of multitasking, the WART. Analysis of the WART revealed that dual-task costs in cognitive performance and walking speed were comparable in both groups, whereas the dual-task cost associated with steps off path more than doubled in participants with diabetes. These findings may suggest that cognitively intact older adults with diabetes do not necessarily demonstrate global, gross impairments in multitasking. However, when walking, they may fail to adopt compensatory strategies in situations in which task demands outstrip attentional and/or functional resources.
In summary, this investigation provides evidence that older adults with type 2 diabetes perform poorly when multitasking while walking. Although these changes did not appear to exert a substantial influence on gait mechanics or functional abilities under normal circumstances, it remains unclear whether they may affect safety in more challenging situations. Clinicians should recognize that widely varying factors may contribute to gait and physical dysfunction in older adults with type 2 diabetes, and be prepared to assess and intervene appropriately.