Women with AFib Experience Faster Cognitive Decline than Men

Scientists say that women with atrial fibrillation are less likely than men to receive prompt diagnosis and treatment, which may put them at risk for a more rapid progression of mild cognitive impairment or dementia.

Atrial fibrillation, often referred to as AFib or AF, is a heart rhythm disturbance that occurs in the heart's upper chambers, disrupting blood flow to the heart's lower chambers.

People with AFib have a five times greater risk of stroke than those without the condition. Because of this, healthcare providers often treat AFib with drugs to control heart rhythm and blood thinning medications to prevent blood clots.

Atrial fibrillation is also associated with an increased risk of cognitive decline and dementia. While the reasons behind this increased risk are unclear, experts think silent strokes occurring over time may be a contributing factor.

Moreover, though AFib tends to impact women more than men, with females experiencing worse outcomes from the disorder, scientists aren't sure whether the progression of cognitive decline differs between men and women with AFib.

Now, a new study published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association and presented on June 23 at ACNAP 2023, a scientific congress of the European Society of Cardiology (ESC), has found that women with AFib may experience a more rapid progression of cognitive decline than men with the disorder.

To conduct the research, scientists recruited 43,630 participants with an average age of 78 years from the National Alzheimer's Coordinating Center (NACC) cohort. About 46% of the participants were female, and all had at least three annual healthcare visits that included tests to determine whether they had normal cognition, mild cognitive impairment (MCI), or dementia.

Among all participants, 11% had AFib at recruitment, and 89% did not have the disorder.

The research team adjusted their analysis for factors such as age, sex, race, and lifestyle factors that could influence the results. They also compared the data to men and women without AFib.

After analyzing the data, the team found that women with AFib were three times more likely to have MCI and dementia at recruitment than women without the heart rhythm condition.

Moreover, during an average four-year follow-up, 30% of the participants experienced a decline in cognitive function, and 21% developed dementia. Of those, women with AFib had a higher risk of their cognitive decline progressing to a worse stage of impairment than women without AFib.

In addition, women with AFib were more likely to shift from normal cognition to MCI and from MCI to vascular dementia.

However, the team found that these associations between rapid cognitive decline and atrial fibrillation were not statistically significant in men.

In an ESC press release, study author Kathryn Wood of Emory University in Atlanta says, "Symptoms of atrial fibrillation in women are often ignored by healthcare providers or attributed to stress or anxiety, so it can go undiagnosed for a long period of time, while men are more likely to be diagnosed and treated quickly."

"Being undiagnosed means not receiving oral anticoagulant medication to prevent blood clots and strokes caused by atrial fibrillation. These women may be having clots that go to small blood vessels in their brain, causing them to lose brain function gradually and develop cognitive impairment," Wood explains.

"The analyses indicate stronger associations between atrial fibrillation and declining cognitive function in women compared with men," Wood notes. "Establishing ways to identify atrial fibrillation patients at the highest risk of cognitive decline and stroke will inform future interventions to prevent or slow the progression to cognitive impairment and dementia."