Could AFib Be a Hidden Risk Factor for Dementia?

We usually think of atrial fibrillation (AFib) as a heart issue—and it is. But a growing body of research now suggests it may also affect the brain. The findings, presented in March 2025 at the European Heart Rhythm Association conference, show that AFib may increase the risk of developing dementia—especially if the diagnosis comes before the age of 70. This may change the way we think about cognitive decline—and how early we need to act.

What Is AFib, and Why Does It Matter?

AFib is an irregular, often rapid heartbeat that affects how blood flows through the heart. It's common in older adults and can raise the risk of stroke and heart failure.

But here's where it gets interesting:AFib may also affect blood flow to the brain, increase the risk of small blood clots, and trigger inflammation—all of which can play a role in cognitive decline.

What the New Study Found

In this recent analysis, researchers followed adults diagnosed with AFib and compared them to individuals without the condition. They discovered:

• People with AFib under the age of 70 had a 21% higher risk of developing dementia

• Those diagnosed with AFib before the age of 65 had a 36% greater risk of early-onset dementia

• The younger the AFib diagnosis, the greater the dementia risk

This suggests that AFib may not just be a secondary condition—it could be a direct contributor to dementia risk, particularly in people diagnosed earlier in life.

What Might Be Causing the Link?

Dr. Paul Drury, a cardiologist not involved in the study, noted that more research is still needed to separate AFib from other possible risk factors like medications, coexisting conditions, or lifestyle habits.

But he also highlighted an important point:

“There appears to be a much stronger association with dementia the earlier a person is diagnosed with AFib.”

Why would that matter?

Researchers believe the longer the brain is exposed to the effects of AFib, the more vulnerable it may become. AFib can lead to:

• Reduced blood flow to the brain

• Tiny clots that may cause “silent strokes” or damage small vessels

• Chronic inflammation that stresses neural tissue over time

It’s not one big event—but a slow accumulation of small harms that may add up to something bigger.

What You Can Do About It

If you have AFib—or you’ve been told you’re at risk—this isn’t a reason to panic. But it is a reason to act.

Here’s what the latest science suggests:

• Early treatment matters. Controlling AFib early may reduce the cumulative effect on the brain

• Medication or rhythm management can reduce stroke and clot risk, which may in turn reduce dementia risk

• Lifestyle changes that support heart health—such as blood pressure control, sleep quality, and regular movement—also protect brain health

• And finally, keep up with cognitive check-ins, especially if you’ve been managing AFib for several years

Final Thoughts

We’ve known for a while that what’s good for the heart is good for the brain. But now we’re learning the opposite may also be true:

Heart rhythm problems like AFib may have long-term consequences for brain health—particularly if left untreated.

The takeaway? Act early. If you’re under 70 and have been diagnosed with AFib, managing it now may help protect not just your heart—but your memory, clarity, and independence in the years to come.

Evidence

1. EHRA 2025: Atrial fibrillation and dementia risk findings presented at the European Heart Rhythm Association Congress, March 2025.

2. Chatterjee NA, et al. (2020). Atrial fibrillation and the risk of cognitive decline and dementia: a systematic review and meta-analysis. Journal of the American Heart Association, 9(1), e014869.

3. Knecht S, et al. (2008). Atrial fibrillation in stroke-free patients is associated with memory impairment and hippocampal atrophy. European Heart Journal, 29(18), 2125–2132.

4. Gaita F, et al. (2013). Cognitive impairment in atrial fibrillation: a systematic review. Heart Rhythm, 10(6), 911–918.