Abstract 11723: Incident Atrial Fibrillation is Associated With Longitudinal Increase in Subclinical Cerebral Infarcts: The Atherosclerosis Risk in Communities (ARIC) Study

Abstract

Background: The mechanisms underlying atrial fibrillation (AF)-related dementia are unclear and may include (1) clinical or subclinical cerebral infarcts (SCIs) or (2) chronic subcortical ischemia which results in white matter hyperintensities (WMH). Previous studies have reported that AF is associated with a higher prevalence of SCIs. However, these studies were mostly cross-sectional and based on whites and hospitalized subjects. To overcome limitations of previous studies, we evaluated the association of incident AF with 10-year change in SCIs and WMH in ARIC, a biracial community-based prospective cohort study. Hypothesis: We hypothesized that incident AF is associated with an increase over time in the number of SCIs. Methods: We included 914 (mean age, 61.7 ± 4.4 years; 38% men; 49% black) participants without prevalent AF, prevalent or incident clinical stroke, and who had brain MRI scans in 1993-95 and 2004-06. SCIs were defined as focal, non-mass lesions ≥3 mm that were bright on T2 and proton density, and dark on T1 images. We used logistic and general linear models to assess association between incident AF and gain in number of SCIs and change in WMH volume, respectively. Results: The median time between the 2 MRIs was 10.5 years. During this period, 46 participants developed AF. Those who developed AF had a 2.2-fold higher odds of gain in SCIs than those without AF. Incident AF, however, was not significantly associated with longitudinal change in WMH volume (Table). Conclusions: Incident AF is associated with an increase over time in the number of SCIs but not with WMH progression. Further research is needed to determine whether the longitudinal increase in SCIs mediates AF-related cognitive decline and dementia.