Abstract 17744: Intracranial Atherosclerosis Disease (ICAD) and Risk of Cognitive Impairment and Dementia: Systematic Review and Meta-Analysis

Abstract

Introduction: Intracranial atherosclerosis disease (ICAD) alters cerebrovascular hemodynamics and is linked with brain structural changes and atrophy. Various studies evaluated the relationship between ICAD and risk of cognitive impairment with mixed results. This study aims to systematically review the current evidence and compile data on the association between ICAD and cognitive impairment and dementia. Methods: PubMed, EMBASE, PsycInfo and Web of Science were searched from January 1-2000, to March 1-2023, without language restriction. Cross-sectional and prospective cohort studies as well as post-mortem studies were included. Studies containing data on the link between ICAD and cognitive impairment and dementia were screened by two independent reviewers for inclusion in a systematic review and meta-analysis. From each study, data on the association between ICAD (at least 50% stenosis in one intracranial vessel) and cognitive impairment and dementia were extracted. Results: A total of 22 (17 observational and 5 post-mortem) unique studies comprising 11,184 individuals (average age range: 59.8 to 87.6 years, 45.7% female, 36.5% Asian) were included in the systematic review. Seven out of 10 cross-sectional studies and 5 out of 7 prospective studies showed a significantly higher risk of cognitive impairment and dementia in association with ICAD.Population-based studies and studies with patients with baseline cognitive impairment or dementia (consist of study participants from Asian, Europe and North America) consistently showed a significant association between ICAD and risk of cognitive decline. In the pooled analysis, ICAD was associated with 1.87-fold (95% confidence interval 1.49-2.35) increased risk of cognitive impairment. Meta-regression analysis did not show a significant impact of age, sex and ethnicity on the findings. All post mortem studies have shown that patients with Alzheimer’s disease and vascular dementia had a higher burden of ICAD as compared to cognitively normal controls. Conclusions: ICAD is associated with a higher risk of cognitive impairment and dementia in various age, sex and ethnic groups. Our findings underscore the importance of intracranial vascular health in brain health and prevention of dementia.