Interactions between blood pressure variability, cerebral autoregulation, and covert cerebral small vessel disease in relation to cognitive performance in community‐dwelling older adults

INTRODUCTION: Both increased blood pressure variability (BPV) and impaired cerebral autoregulation (CA) have been linked to cerebral small vessel disease (CSVD) and cognitive performance, but whether they independently or interactively influence cognition remains unclear. METHODS: We analyzed 300 community-dwelling participants. Dynamic CA, beat-to-beat BPV measures, and MRI-based CSVD markers were quantified. Multivariate linear regression and mediation analyses assessed the associations and interactions between CA, BPV, CSVD, and Montreal Cognitive Assessment (MoCA) scores. RESULTS: Higher BPV was associated with greater CSVD burden. A significant interaction between CA and BPV indicated that the negative association between BPV and MoCA scores was evident only under impaired CA. Mediation analyses demonstrated that BPV influenced MoCA score directly rather than through CSVD. DISCUSSION: Increased BPV and impaired CA interacted and are associated with poorer cognitive performance independently of detectable CSVD, suggesting a potential link between hemodynamic instability and cognitive vulnerability in community-dwelling older adults.