Abstract WMP22: Higher Burden of Cerebral Small Vessel Disease is Associated With Risk of Incident Stroke in Community-Dwelling Individuals

Abstract

Background: Mild manifestations of individual cerebral small vessel disease (CSVD) markers are common and may not denote increased risk, but high CSVD burden identifies individuals at increased risk of stroke and dementia. Scores incorporating multiple CSVD markers may better identify a person’s risk, but it remains unclear if they offer benefit beyond tools based on clinical factors alone such as the revised Framingham Stroke Risk Profile (FSRP). Therefore, we related a multi-marker CSVD score to risk of incident stroke and compared the findings with the FSRP in community-dwelling individuals. Methods: Framingham Heart Study (FHS) participants aged ≥55 years, free of stroke and dementia and with brain magnetic resonance imaging (MRI) ratings of CSVD markers were included. A multi-marker CSVD score reflecting increasing CSVD burden was used (one point each for presence of cerebral microbleeds, severe perivascular spaces, extensive white matter hyperintensities, covert brain infarcts, and cortical superficial siderosis, ranging 0-5). Multivariable Cox proportional hazards regression analyses were used to relate CSVD score to incident stroke. Results: Among 1,154 participants (46% male, mean age 70.9±8.7), 590 (51%) had score 0, 352 (31%) had score 1, 164 (14%) had score 2, and 48 (4%) had score ≥ 3. Over a median follow-up of 8.2 years (Q1-Q3: 5.1-12.5) from the time of MRI, 92 (8%) developed stroke. In models adjusting for time interval between clinic exam and MRI, FHS cohort, and FSRP score, number of CSVD manifestations was associated with increased risk of stroke in a dose-dependent manner: score 1 (HR: 1.73; 95% CI 1.05-2.84), score 2 (HR 1.83; 95% CI: 1.01-3.30), and score ≥ 3 (HR: 3.31; 95% CI: 1.50-7.28) in relation to participants with no CSVD markers. In comparison, a 5-percent increase in FSRP alone was associated with increased risk of stroke (HR: 1.25; 95% CI 1.15-1.36). Interpretation: Higher CSVD burden is associated with increased risk of stroke, beyond the effect explained by risk factors in the FSRP. These findings support consideration of CSVD burden to identify risk of stroke in community-dwelling individuals.