Dementia risk may be higher if heart abnormality present

Structural or functional abnormalities within the heart’s left atrium may increase a person’s risk of developing dementia later in life by 35%, according to new research.

Dementia risk increased even among those who did not experience atrial fibrillation or stroke, two conditions known to be associated with dementia.

The left atrium is one of four chambers of the heart and is responsible for receiving blood from the lungs and pumping it into the left ventricle, which then pumps the blood to the rest of the body.

An abnormality in the structure or functioning of the left atrium, known as atrial cardiopathy, can often serve as a biomarker, or predictor, of a person’s cardiac risk. 

Atrial cardiopathy is associated with an increased risk of stroke and atrial fibrillation, which are both linked to an enhanced risk of dementia.

In the study led by Michelle C. Johansen, M.D., Ph.D., an assistant professor of neurology at The Johns Hopkins University School of Medicine in Baltimore, the research team aimed to determine the relationship between atrial cardiopathy and dementia, and if so, whether it is independent of atrial fibrillation and stroke. 

The study results highlight the need to get a better understanding of the relationship and mechanisms between a state of atrial dysfunction, that may be subclinical (not presenting symptoms) and the newly uncovered association with dementia, the researchers noted.

Participants in the current analysis were part of a larger study group of more than 15,000 people originally recruited for the ongoing Atherosclerosis Risk in Communities (ARIC) study, which began in 1987 to research heart health in people living within four diverse communities throughout the U.S.

The participants with atrial cardiopathy appeared to be 35% more likely to develop dementia. When the researchers adjusted for participants who experienced atrial fibrillation and stroke, even after accounting for other vascular risks, they still observed a respective 31% and 28% increase in dementia risk in patients with atrial cardiopathy.

The researchers suggested that a state of atrial cardiopathy leading to dementia is not a result of atrial fibrillation or stroke alone.

Photo by Ali Hajiluyi