Heart arrhythmia linked to smaller brains, study shows

Heart arrhythmia linked to smaller brains, study shows

People who experience atrial fibrillation (AF), a heart arrhythmia, may also have a smaller brain—specifically, reduced frontal lobe volume—a new study suggests.

AF is a serious cardiovascular condition that is associated with an increased risk of stroke, heart failure, and death, as well as cognitive decline and increased risk of dementia.

But little is known about the impact of AF on brain structure in people whose cognition is intact.

For the new study, researchers used MRI to look at the relationship between AF and brain volume.

They examined total cerebral volume, frontal lobe volume, temporal lobe volume, hippocampal volume, and white matter hyper-intensity volume in patients without prior stroke or dementia.

The findings, published in the journal Heart Rhythm, show that AF is associated with smaller frontal lobe volumes, even after adjusting for age, gender, vascular risk factors, and APOE4 (a gene independently linked to smaller brain volumes).

“We believe that good heart health also contributes to good brain health, and given that the incidence of AF is expected to more than double in the next three decades, we are interested in understanding the association between AF and brain anatomy,” says corresponding author Rhoda Au, professor of epidemiology and neurology at Boston University.