The Presence of Covert Brain Infarcts or White Matter Disease Is Associated with Increased Stroke and Dementia Risks in a Large Integrated Healthcare System
Mai Nguyen-Huynh1, Eric Puttock2, Wansu Chen2, Lester Leung3, David Kent4
1Department of Neurology and Division of Research, Kaiser Permanente Northern California, 2Department of Research & Evaluation, Kaiser Permanente Southern California, 3Department of Neurology, 4Predictive Analytics and Comparative Effectiveness Center, Tufts Medical Center
Objective:
To determine prognostic implications of covert brain infarcts (CBI) and white matter disease (WMD) on future stroke and dementia risks.
Background:
CBI and WMD are frequently detected incidentally on neuroimaging in adults without clinical stroke.
Design/Methods:
We applied natural language processing (NLP) to radiology reports from head CT and brain MRI performed between 2009 and 2022 among adults aged ≥50 years in Kaiser Permanente Northern California, excluding those with prior ischemic stroke, transient ischemic attack, or dementia. NLP algorithms were trained and validated against manually reviewed reports to identify CBI and WMD with high accuracy. Multivariate Cox proportional hazards regression models estimated the association of CBI and WMD with incident stroke and dementia, ascertained from electronic health records, adjusting for vascular risk factors.
Results:
Among 255,112 adults (mean age 63.5 ± 10.2 years; 60% female; ethnically diverse), 73.6% underwent CT and 26.4% MRI. Median follow-up was 3.5 years. The prevalence of CBI was 2.2% and 27.6% of WMD. For stroke, CBI was associated with increased risk on both CT (HR = 1.45; 95% CI: 1.36–1.68) and MRI (HR = 2.10; 95% CI: 1.82–2.43). WMD effects on stroke varied by age: HR = 2.21 (95% CI: 2.00–2.44) for age <70, and HR = 1.85 (95% CI: 1.67–2.05) for age ≥70. For dementia, CBI was associated with higher risk (HR = 1.63; 95% CI: 1.47–1.80). WMD effects varied by age and modality: for <70 years, HR = 3.31 (95% CI: 2.82–3.89) on CT and HR = 2.50 (95% CI: 2.13–2.94) on MRI; for ≥70 years, HR was 2.06 (95% CI: 1.76-2.42) on CT and 1.56 (95% CI: 1.33-1.83) on MRI.
Conclusions:
The presence of CBI or WMD on neuroimaging was associated with a significant increased risk of future stroke and dementia. These findings support further research into targeted prevention strategies for patients with these incidental findings.
Disclaimer: Abstracts were not reviewed by Neurology® and do not reflect the views of Neurology® editors or staff.