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Effect of Formal Education on Vascular Cognitive Impairment after Stroke: A Meta-analysis and Study in Young-Stroke Patients

Published online by Cambridge University Press:  09 January 2017

Roy P.C. Kessels*
Affiliation:
Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands Department of Medical Psychology, Radboud University Medical Center, Nijmegen, the Netherlands Vincent van Gogh Institute for Psychiatry, Venray, the Netherlands
Willem Sake Eikelboom
Affiliation:
Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands
Pauline Schaapsmeerders
Affiliation:
Department of Neurology, Radboud University Medical Center, Nijmegen, the Netherlands
Noortje A.M. Maaijwee
Affiliation:
Department of Neurology, Radboud University Medical Center, Nijmegen, the Netherlands
Renate M. Arntz
Affiliation:
Department of Neurology, Radboud University Medical Center, Nijmegen, the Netherlands
Ewoud J. van Dijk
Affiliation:
Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands Department of Neurology, Radboud University Medical Center, Nijmegen, the Netherlands
Frank-Erik de Leeuw
Affiliation:
Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands Department of Neurology, Radboud University Medical Center, Nijmegen, the Netherlands
*
Correspondence and reprint requests to: R.P.C. Kessels, Radboud University, Donders Institute for Brain, Cognition and Behaviour, Montessorilaan 3, 6525 HR Nijmegen, The Netherlands. E-mail: r.kessels@donders.ru.nl

Abstract

Objectives: The extent of vascular cognitive impairment (VCI) after stroke varies greatly across individuals, even when the same amount of brain damage is present. Education level is a potentially protective factor explaining these differences, but results on its effects on VCI are inconclusive. Methods: First, we performed a meta-analysis on formal education and VCI, identifying 21 studies (N=7770). Second, we examined the effect of formal education on VCI in young-stroke patients who were cognitively assessed on average 11.0 (SD=8.2) years post-stroke (the FUTURE study cohort). The total sample consisted of 277 young-stroke patients with a mean age at follow-up 50.9 (SD=10.3). Age and education-adjusted expected scores were computed using 146 matched stroke-free controls. Results: The meta-analysis showed an overall effect size (z') of 0.25 (95% confidence interval [0.18–0.31]), indicating that formal education level had a small to medium effect on VCI. Analyses of the FUTURE data showed that the effect of education on post-stroke executive dysfunction was mediated by age (β age −0.015; p<.05). Below-average performance in the attention domain was more frequent for low-education patients (χ2(2)=9.8; p<.05). Conclusions: While education level was found to be related to post-stroke VCI in previous research, the effects were small. Further analysis in a large stroke cohort showed that these education effects were fully mediated by age, even in relatively young stroke patients. Education level in and of itself does not appear to be a valid indicator of cognitive reserve. Multi-indicator methods may be more valid, but have not been studied in relation to VCI. (JINS, 2017, 23, 223–238)

Type
Critical Reviews
Copyright
Copyright © The International Neuropsychological Society 2017 

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