Post-stroke cognitive impairment - A cross-sectional comparison study between mild cognitive impairment of vascular and non-vascular etiology

Abstract

PurposeTo elucidate the cognitive profiles of post-stroke vascular mild cognitive impairment (VaMCI) in comparison to MCI of non-vascular etiology and cognitively normal healthy controls at a tertiary-care hospital in southern India. ResultsLogistic regression analysis adjusted for age and sex comparing VaMCI [N=50] with controls [N=27] revealed significant impairment in visual, verbal learning-recall and executive function scores. As compared to the MCI group [N=36], VaMCI had significantly higher scores on Weschler's Memory Scale (WMS) verbal subset delayed recall scores (p=0.045, odds ratio [OR]=2.62, 95% CI=1.02–6.76) with lower scores on WMS-visual immediate learning scores (p=0.042, OR=0.35, 95% CI=0.13–0.96), Rey Auditory Verbal Learning Test (RAVLT) total learning scores (p=0.001, OR=0.17, 95% CI=0.06–0.48) and 20 minute recall (p=0.026, OR=0.33, 95% CI=0.12–0.88), Delayed Matching to Sample test (DMS-48) abstract immediate (p=0.002, OR=0.20, 95% CI=0.07–0.56), abstract delayed recognition sub-sets (p=0.014, OR=0.28, 95% CI=0.10–0.78) and made more total errors on Wisconsin Card Sorting Test (WCST; p=0.040, OR=2.70, 95% CI=1.05–7.14) while the MCI group significantly had more commission errors on RAVLT (p≤0.001, OR=0.13, 95% CI=0.05–0.38) and WCST – perseverative errors (p=0.036, OR=0.30, 95% CI=0.10–0.93). Significant differences were noted in word-list learning-recall (p=0.012) and WMS verbal delayed recall (p=0.014) between VaMCI with mild versus moderate to severe deep white matter hyperintensities on neuroimaging. ConclusionsCognitive impairment following minor stroke involves episodic verbal and visual memory over and above executive function in comparison to MCI of non-vascular etiology. Close cognitive followup is warranted with adequate risk stratification and management especially in the presence of sub-cortical leukoaraiosis which is contributory to cognitive decline in this group of patients.