Association of Ischemic Imaging Phenotype With Progression of Brain Atrophy and Cerebrovascular Lesions on MRI

Background and ObjectiveTo investigate the association of silent vascular lesions, imaging negative ischemia, and symptomatic cerebrovascular disease with long-term progression of brain atrophy and cerebrovascular lesions in patients with arterial disease.MethodsWithin the Second Manifestations of Arterial Disease–Magnetic Resonance (SMART-MR) study, stroke status of participants at baseline was classified as no cerebrovascular disease (reference group, n = 829), symptomatic cerebrovascular disease (n = 206), silent vascular lesion (n = 157), and imaging-negative ischemia (n = 90) according to clinical and MRI findings. With the use of linear mixed models, changes in brain and white matter hyperintensity (WMH) volumes at baseline and during 12 years of follow-up were studied in stroke classifications. Relative risks were estimated for new infarcts during follow-up associated with stroke classifications. Analyses were adjusted for age, sex, cardiovascular risk factors, and medications.ResultsSymptomatic cerebrovascular disease associated with 0.35 SD (95% confidence interval [CI] 0.24–0.47) smaller brain volume and 0.61 SD (95% CI 0.48–0.74) larger WMH volume at baseline and increased risk for new infarcts during follow-up (risk ratio [RR] 2.89, 95% CI 2.00–4.16). Silent vascular lesions were associated with 0.15 SD (95% CI 0.01–0.88) smaller brain volume, 0.02 SD (95% CI 0.01–0.03) steeper brain atrophy slope, and 0.48 SD (95% CI 0.32–0.64) larger WMH volume at baseline, in addition to increased risk for lacunes (RR 2.08, 95% CI 1.48–2.94). Individuals with imaging-negative ischemia had increased risk for cortical infarcts (RR 2.88, 95% CI 2.17–3.82).DiscussionPatients with symptomatic cerebrovascular disease, silent vascular lesions, or imaging-negative ischemia have a different course of brain volume loss and cerebrovascular lesion development. These findings may have implications for future stroke risk and dementia and need further investigation.