Research Reports - Decline in cognitive function due to diffuse axonal injury does not necessarily imply a corresponding decline in ability to perform activities
Disabil Rehabil. 2015 Oct 24:1-10. [Epub ahead of print]
Björkdahl A(1,)(2), Esbjörnsson E(2), Ljungqvist J(2), Skoglund T(2), Stibrant
PURPOSE: The study explored the direction of change (decline vs. improvement)
after diffuse axonal injury (DAI) in the domains of the ICF: body structure, body
function, and activity.
METHODS: Thirteen patients with DAI were assessed by using diffusion tensor
imaging (DTI) to measure body structure, the Barrow Neurological Institute Screen
for Higher Cerebral Functions (BNIS) to measure body function, and the Assessment
of Motor and Process Skills (AMPS) to measure activity. The DTI, BNIS, and AMPS
were applied at the acute phase (A1), and at 6 and 12 months post-injury (A2 and
A3). Visual and statistical analyses were conducted to explore time-dependent
changes in the ICF domains.
RESULTS: Improvements were observed for most patients in all ICF domains from
injury until six months. Thereafter, the results diverged, with half of the
subjects showing a decline in DTI and BNIS scores between A2-A3, and all but one
of the patients exhibiting identical or better A2-A3 AMPS process skill scores.
CONCLUSIONS: From 6 to 12 months post-injury, some patients underwent an ongoing
degenerative process, causing a decline in cognitive function. The same decline
was not observed in the activity measure, which might be explained by the use of
compensatory strategies. Implications for rehabilitation In rehabilitation it is
essential to be aware that in some cases with TBI, an ongoing degenerative
process in the white matter can be expected, causing an adverse late effect on
cognitive function. The cognitive decline, caused by DAI, does not necessarily
mean a concurrent decrease in activity performance, possibly explained by the use
of compensatory strategies. This suggests that, after the post-acute phase,
rehabilitation offering strategy training may be beneficial to enhance every-day
functioning. Strategy use requires awareness, which imply the need to assess
level of awareness in order to guide rehabilitation.