Cerebral Microvascular Injury and Physical Function in Older Patients With Atrial Fibrillation: Evidence for...

Area of Science:

• Neurology
• Cardiology
• Geriatrics

Background:

• Atrial fibrillation (AF) is a known risk factor for cerebrovascular diseases.
• Cerebral small vessel disease (CSVD) encompasses various brain pathologies, including white matter hyperintensities (WMH), lacunes, and microbleeds.
• Previous research suggests a link between AF and CSVD, but sex-specific differences and their impact on functional outcomes remain underexplored.

Purpose of the Study:

• To investigate sex-specific differences in CSVD prevalence and patterns in patients with and without AF.
• To examine the association between AF, CSVD, and cognitive and physical performance.
• To determine if CSVD markers mediate the relationship between AF and functional decline.

Main Methods:

• Observational cross-sectional cohort study of 1044 memory clinic patients.
• Brain MRI was used to assess CSVD markers: WMH (Fazekas ≥2), lacunes (≥1), and microbleeds (≥3).
• Logistic regression and mediation analyses were employed to examine associations and mediating effects.

Main Results:

• AF was associated with increased WMH in men and more microbleeds in women.
• Patients with AF exhibited poorer physical performance (reduced gait speed and Short Physical Performance Battery scores) but not cognitive impairment.
• WMH partially mediated the association between AF and reduced physical performance, with a stronger effect observed in men.

Conclusions:

• AF is associated with distinct sex-specific CSVD patterns in older adults.
• CSVD, particularly WMH, plays a significant role in mediating AF-related physical performance decline, especially in men.
• Targeting CSVD may be crucial for preserving physical function in individuals with AF, necessitating sex-specific risk stratification.