Lower cardiac output is a risk factor for faster cerebral atrophy over a 11-year follow-up period in APOE-ε4 carriers.

INTRODUCTION

Subclinical lower cardiac output (volume of blood pumped per minute) cross-sectionally relates to smaller cerebral gray matter volumes in older adults. This study relates cardiac output to longitudinal gray matter volumes among middle-aged and older adults over an 11-year period.

METHODS

Linear regression (cross-sectional) and mixed effects (longitudinal) models related baseline cardiac output to gray matter volume trajectory, adjusting for demographic factors. Secondary models tested cardiac output × apolipoprotein E (APOE) -ε4 status interactions.

RESULTS

Lower cardiac output related to smaller brain volumes (p-values < 0.04) in APOE-ε4 positive participants only. In longitudinal models, baseline cardiac output interacted with APOE-ε4 status (p = 0.006). Lower baseline cardiac output related to greater increase in inferior lateral ventricle volume over time in APOE-ε4 carriers (p = 0.01) only.

DISCUSSION: Results suggest among APOE-ε4 carriers, subclinical cardiac dysfunction relates to greater neurodegeneration cross-sectionally and longitudinally. However, results must be interpreted with caution and replicated.