Impact of Educational Inequality on the Incidence of Post-stroke Vascular Mild Cognitive Impairment – Application of the Previous Study on Stratified Education-adjusted MoCA Assessment

Congratulations to Kulrithra PisanuwongrakParunyou Julayanont, and Kenneth M. Heilman on the publication of “Impact of Educational Inequality on the Incidence of Post-stroke Vascular Mild Cognitive Impairment – Application of the Previous Study on Stratified Education-adjusted MoCA Assessment.”  This article was published in the April 9th issue of Neurology.

Abstract

Objective: To calculate the incidence of vascular mild cognitive impairment (VaMCI) and vascular dementia (VaD) in post-stroke patients, using normative MoCA scores stratified by education level (Julayanont 2013).

Background: Post-stroke vascular cognitive impairment (VCI) ranges from VaMCI to VaD. Recent studies on the incidence of VaMCI reported a wide array of the results, from 20% to 80%. Educational inequality may influence how accurately the single cut-off value can determine patients as demented or only mildly-cognitive impaired.

Design/Methods: Acute ischemic stroke patients without pre-existing cognitive problems and depression were assessed. Their education levels were categorized into ‘illiterate’, ‘below high school’, and ‘above high school’. MoCA tests were obtained at 3-month follow-up. Normative and standard cut-off values were used to classify patients as ‘Normal’ or ‘VCI’. VCI groups were further divided into ‘VaMCI’ or ‘VaD’ according to independency assessed by Lawton’s Instrumental Activities of Daily Living (IADL) Scale.

Results: 93 normal subjects aged 60–90 years with Clinical Dementia Rating of 0.0 were recruited to take the MoCA test. The mean (SD) of total MoCA score according to their education level were as follows: illiterate MoCA score =14.09(3.74), below high school score =20.59(2.85), and above high school score =26.21 (2.15). VCI diagnosis was made by MoCA ≤ −1.5SD (≤8, ≤16, and ≤23 respectively). 119 stroke participants were recruited. The number (%) of normal, VaMCI and VaD by normative MoCA cut-off were 42(35.3%), 66 (55.5%) and 11(9.2%) respectively. With standard MoCA cut-off score of 26, the results were 21(17.6%), 87(73.1%) and 11(9.2%) respectively.

Conclusions: This is the first study using stratified education-adjusted cutoff values in Thailand. A discrepancy between the incidence of post-stroke VaMCI with and without effect of education (55.5% vs 73.1%) highlighted its importance in the diagnosis of VaMCI. Further validating studies are needed and application to patients with neurodegenerative diseases may be valuable.