Balance, attention, and dual-task performance during walking after brain injury: associations with falls history.

OBJECTIVE

To examine the relationship between balance, attention, and dual-task performance in individuals with acquired brain injury.

DESIGN

Cross-sectional study.

SETTING

Rehabilitation center and supported living program.

PARTICIPANTS

Twenty-four individuals aged 18 to 58 years (mean = 39 years) with acquired brain injury who were able to ambulate 40 ft with (29%) or without an assistive device. Fifty-eight percent were independent community ambulators. Fifty-four percent had fallen in the past 6 months; and 42% reported feeling unsteady with standing or walking.

INTERVENTIONS: Participants completed a battery of balance, attention, and dual-task assessments.

MAIN OUTCOME MEASURES: Balance: Berg Balance Scale (BBS), Four Square Step Test (FSST), High Level Mobility Assessment Test (HiMAT); Attention: Symbol Digit Modalities Test (SDMT), Moss Attention Rating Scale (MARS), modified for a single test session; and a walking dual-task assessment, the Walking and Remembering Test.

RESULTS

Mean scores: BBS, 48 of 56; FSST, 19.6 seconds; HiMAT, 20 of 54; SDMT, 30 correct; and MARS, 80. Dual-task costs were observed with variable patterns across subjects: 48% demonstrated primarily motor slowing, 9% had reduced cognitive accuracy without motor slowing, and 35% demonstrated decrements in both tasks. Subjects with a falls history had more impaired balance (HiMAT, BBS, and FSST, all P <.026) but were not significantly different in dual-task performance or attention measures.

CONCLUSIONS

The test battery matched the range of motor and cognitive abilities of the sample. Balance was more strongly related to falls history than measures of attention or dual-task performance. Injury chronicity may have allowed some subjects to develop strategies to optimize dual-task performance. Alternatively, motor slowing in dual-task conditions may be an adaptive strategy, allowing performance of multiple tasks with reduced safety risk. Further investigation in this area is warranted to clarify the utility of dual-task methods in identifying falls risk after brain injury.