Predictors of post-stroke cognitive impairment using acute structural MRI neuroimaging : A systematic review and meta-analysis

BACKGROUND: Stroke survivors are at an increased risk of developing post-stroke cognitive impairment and post-stroke dementia; those at risk could be identified by brain imaging routinely performed at stroke onset. AIM: This systematic review aimed to identify features which are associated with post-stroke cognitive impairment (including dementia), on magnetic resonance imaging (MRI) performed at stroke diagnosis. SUMMARY OF REVIEW: We searched the literature from inception to January 2022 and identified 10,284 records. We included studies that performed MRI at the time of stroke (0-30 days after a stroke) and assessed cognitive outcome at least three months after stroke. We synthesised findings from 26 papers, comprising 27 stroke-populations (N=13,114, average age range=40-80 years, 19-62% female). When data were available, we pooled unadjusted (ORu) and adjusted (ORa) odds ratios.We found associations between cognitive outcomes and presence of cerebral atrophy (3 studies, N=453, ORu=2.48, 95%CI=1.15-4.62), presence of microbleeds (2 studies, N=9151, ORa=1.36, 95%CI=1.08-1.70), and increasing severity of white matter hyperintensities (3 studies, N=704, ORa=1.26, 95%CI=1.06-1.49). Increasing cerebral small vessel disease score was associated with cognitive outcome following unadjusted analysis only (2 studies, N=499, ORu=1.34, 95%CI=1.12-1.61; 3 studies, N=950, ORa=1.23, 95%CI=0.96-1.57). Associations remained after controlling for pre-stroke cognitive impairment. We did not find associations between other stroke features and cognitive outcome, or there were insufficient data. CONCLUSIONS: Acute stroke MRI features may enable healthcare professionals to identify patients at risk of post-stroke cognitive problems. However, there is still substantial uncertainty about the prognostic utility of acute MRI for this.