Education Attenuates the Negative Impact of Traumatic Brain Injury on Cognitive Status

Department of Physical Medicine and Rehabilitation, UMDNJ -New Jersey Medical School, Newark, NJ. Electronic address: .
Archives of physical medicine and rehabilitation (Impact Factor: 2.57). 08/2013; 94(12). DOI: 10.1016/j.apmr.2013.07.023
Source: PubMed

ABSTRACT To investigate the cognitive reserve hypothesis in survivors of traumatic brain injury (TBI). Cognitive impairment is prevalent among survivors of moderate and severe TBI, although some survivors fare better than others. The cognitive reserve hypothesis states that intellectual enrichment (estimated with education) protects against cognitive decline in neurologic populations (e.g., Alzheimer's disease).
Forty-four survivors of moderate or severe TBI and 36 healthy controls participated in this cross-sectional study at a medical rehabilitation research center.
Not Applicable.
Intellectual enrichment was estimated with educational attainment. Group was defined as TBI or healthy control. Current cognitive status (processing speed, working memory, episodic memory) was evaluated with neuropsychological tasks.
TBI survivors exhibited worse cognitive status than healthy persons (p < .001), and education was positively correlated with cognitive status in TBI survivors (r = .54, p < .001). Most importantly, regression analysis revealed an interaction between group and education (R2Δ = .036, p = .004), whereby higher education attenuated the negative impact of TBI on cognitive status. TBI survivors with lower education performed much worse than matched healthy persons, but this TBI-related performance discrepancy was attenuated at higher levels of education.
Higher intellectual enrichment (estimated with education) reduces the negative effect of TBI on cognitive outcomes, thereby supporting the cognitive reserve hypothesis in persons with TBI. Future work is necessary to investigate whether intellectual enrichment can build cognitive reserve as a rehabilitative intervention in survivors of TBI.

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