The Montreal Cognitive Assessment (MoCA) is superior to the Mini-Mental State Examination (MMSE) for the detection of vascular cognitive impairment after acute stroke

Abstract

Background: The majority of patient with post-stroke Vascular Cognitive Impairment (VCI) have Vascular Cognitive Impairment No Dementia (VCIND). The Mini-Mental State Examination (MMSE) has been criticized as a poor screening test for VCIND due to insensitivity to visuospatial and executive function impairments. The Montreal Cognitive Assessment (MoCA) was designed to be more sensitive to such deficits and may therefore be a superior screening instrument for VCIND.

Methods: Stable patients within 14days of their index stroke without significant physical disability, aphasia, dysarthria, active psychiatric illness or pre-existing dementia were eligible. Cognitive and neurological measures were administered after informed consent.

Results: 100 patients were recruited. Of the 57 patients with unimpaired MMSE scores, 18 (32%) patients had an impaired MoCA score. By comparison, only 2 out of the 41 (4.9%) patients with unimpaired MoCA scores had impaired MMSE scores. Moreover, MMSE domain subtest scores could not differentiate between groups of differing screening test results, whilst MoCA domain subtest scores (Visuospatial/Executive Function, Attention and Recall) could.

Conclusion: The MoCA is more sensitive than the MMSE in screening for cognitive impairment after acute stroke. Longitudinal studies are required to establish the prognostic value of MoCA and MMSE evaluation in the acute post-stroke period for cognitive impairment as defined by the standard method of formal neuropsychological evaluation 3-6 months after stroke.