Archives of Physical Medicine and Rehabilitation
Original articlePostrecovery Cognitive Decline in Adults With Traumatic Brain Injury
Section snippets
Participants
The study sample comprised 33 patients with moderate to severe TBI. All participants were part of a larger, longitudinal study on cognitive and motor recovery that was undertaken in the inpatient neurorehabilitation program at the Toronto Rehabilitation Institute.
This study was approved by the Research Ethics Board of the Toronto Rehabilitation Institute.
Participants in the larger study underwent neuropsychological testing at 2, 5, and 12 months postinjury and met the following inclusion
Group Data
Descriptive statistics for the standardized neuropsychological measures for the TBI sample are displayed in table 2. Means at the 12-month baseline and follow-up assessments fell within the normative range across all tests. The only statistically significant change across time, after adjusting for multiple comparisons, was an improvement on the TMT Part A (t30=3.50, P=.001). The magnitude of change was one half an SD, and showed a medium effect size. Cohen d45effect size differences for all
Discussion
In some settings, there is a tacit assumption that cognitive gains made over the early recovery period are maintained into the long-term or may even increase. However, using the RCI, we showed that 27% of our sample (9 of 33) manifested cognitive decline on at least 2 subtests (of a 12 subtest neuropsychological battery) between a 12-month baseline evaluation and a follow-up evaluation conducted 1 to 4 years later. Although most individuals in the current study remained stable or showed ongoing
Conclusions
The results of this study suggest that postrecovery decline does occur in a considerable proportion of individuals with moderate to severe TBI and may affect an array of cognitive functions. These findings are important clinically because they demonstrate that a normalized early recovery does not necessarily predict maintenance of recovery, let alone continued recovery. Our findings also provide some clues about the risk factors that may contribute to late decline. The strongest correlate of
Acknowledgments
The authors wish to thank Leslie Miller, MA, for her assistance with patient testing and Kadeen Johns, BA, for her ongoing administrative support. The authors acknowledge the support of Toronto Rehabilitation Institute who receives funding under the Provincial Rehabilitation Research Program from the Ministry of Health and Long-Term Care in Ontario. The views expressed do not necessarily reflect those of the Ministry.
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Cited by (0)
Supported by the Canadian Institutes of Health Research (grant no. MOP-67072), Physicians' Services Incorporated (grant no. 05-50), and the Ontario Mental Health Foundation.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.
Reprints not available from the author.