Left ventricular geometry, brain architecture, and cognition: an observational study.

Area of Science:

• Cardiology
• Neurology
• Neuroimaging
• Gerontology

Background:

• Cardiovascular diseases and dementia share risk factors and often coexist.
• Understanding the cardiovascular-brain interaction is crucial for managing health in older adults.

Purpose of the Study:

• To investigate the relationship between cardiovascular phenotypes, brain structure, and cognitive abilities.
• To explore the role of hippocampal volume in mediating the cardiovascular-cognition link.

Main Methods:

• Analysis of 15,519 UK Biobank participants using cardiovascular magnetic resonance imaging (MRI) biomarkers.
• Confirmatory factor analysis to derive latent variables for cardiac function and geometry (gSyst, gDiast, gGeom) and aortic distensibility (AoD).
• Multivariable regression models assessed associations with brain MRI phenotypes and cognition, with mediation analysis for hippocampal volume.

Main Results:

• Cardiac geometry (gGeom) showed the strongest association with hippocampal volume and was the only cardiovascular phenotype linked to better cognition (fluid intelligence, reaction time).
• Hippocampal volume mediated the positive association between gGeom and cognition.
• Other cardiovascular phenotypes (gSyst, gDiast, AoD) had weaker associations with brain structure and were not linked to cognition.

Conclusions:

• Ventricular geometry is a key cardiovascular phenotype associated with brain architecture and cognitive function.
• Hippocampal volume may play a mediating role in the cardiovascular-cognition relationship, warranting further causal investigation.