Debette S, et al. - For the most common age-related neurological diseases, stroke and dementia, researchers determined the clinical significance of vascular brain injury (VBI) (ie, white matter hyperintensities of presumed vascular origin, magnetic resonance imaging (MRI)-defined covert brain infarcts, cerebral microbleeds, and perivascular spaces) to optimize prevention strategies. In this systematic review and meta-analysis of more than 16,000 participants, evidence was reported that VBI MRI markers are of major clinical significance.

Methods

• For this investigation, investigators searched for articles in PubMed between 1966 and December 22, 2017, studying the association of four MRI markers of covert VBI: white matter hyperintensities (WMHs) of presumed vascular origin, MRI-defined covert brain infarcts (Bis), cerebral microbleeds (CMBs), and perivascular spaces (PVSs) with incident stroke, dementia, or death.
• Data from prospective longitudinal cohort studies that had 50 or more adults were collected.
• For WMH burden, they performed inverse variance–weighted meta-analyses with random effects and z score–based meta-analyses.
• The significance threshold was P < .003 (17 independent tests).
• They complied with the meta-analyses of Observational Studies in Epidemiology guidelines.
• Main outcomes and measures included stroke (hemorrhagic and ischemic), dementia (all and Alzheimer disease), and death.

Results

• Of the 2,846 articles identified, 94 were eligible, with a maximum of 14,529 WMH participants, 16,012 BI participants, 15,693 CMB participants and 4,587 PVS participants.
• Findings suggested an association of extensive WMH burden with higher risk of incident stroke (hazard ratio [HR], 2.45; 95% CI, 1.93-3.12; P < .001), ischemic stroke (HR, 2.39; 95% CI, 1.65-3.47; P < .001), intracerebral hemorrhage (HR, 3.17; 95% CI, 1.54-6.52; P=.002), dementia (HR, 1.84; 95% CI, 1.40-2.43; P < .001), Alzheimer disease (HR, 1.50; 95% CI, 1.22-1.84; P < .001), and death (HR, 2.00; 95% CI, 1.69-2.36; P < .001).
• It was noted that presence of MRI-defined BIs was correlated with higher risk of incident stroke (HR, 2.38; 95% CI, 1.87-3.04; P < .001), ischemic stroke (HR, 2.18; 95% CI, 1.67-2.85; P < .001), intracerebral hemorrhage (HR, 3.81; 95% CI, 1.75-8.27; P < .001), and death (HR, 1.64; 95% CI, 1.40-1.91; P < .001).
• Presence of CMBs was related to increased risk of stroke (HR, 1.98; 95% CI, 1.55-2.53; P < .001), ischemic stroke (HR, 1.92; 95% CI, 1.40-2.63; P < .001), intracerebral hemorrhage (HR, 3.82; 95% CI, 2.15-6.80; P < .001), and death (HR, 1.53; 95% CI, 1.31-1.80; P < .001).
• PVS data were limited and insufficient to perform meta-analyses, but suggested a correlation of high PVS burden with an increased risk of stroke, dementia and death, but confirmation is required.