GUM DISEASE BACTERIUM LINKED TO INCREASED RISK OF ATRIAL FIBRILLATION

Tempted to skip the floss? Your heart might thank you if you don't. A new study from Hiroshima University (HU) finds that the gum disease bacterium Porphyromonas gingivalis (P. gingivalis) can slip into the bloodstream and infiltrate the heart. There, it quietly drives scar tissue buildup-known as fibrosis-distorting the heart's architecture, interfering with electrical signals, and raising the risk of atrial fibrillation (AFib).

Clinicians have long noticed that people with periodontitis, a common form of gum disease, seem more prone to cardiovascular problems. One recent meta-analysis has linked it to a 30% higher risk of developing AFib, a potentially serious heart rhythm disorder that can lead to stroke, heart failure, and other life-threatening complications. Globally, AFib cases nearly doubled in under a decade, rising from 33.5 million in 2010 to roughly 60 million by 2019. Now, scientific curiosity is mounting in how gum disease might be contributing to that surge.

Past research has pointed to inflammation as the likely culprit. When immune cells in the gums rally to fight infection, chemical signals they release can inadvertently seep into the bloodstream, fueling systemic inflammation that may damage organs far from the mouth.

But inflammation isn't the only threat escaping inflamed gums. Researchers have discovered DNA from harmful oral bacteria in heart muscle, valves, and even fatty arterial plaques. Among them, P. gingivalis has drawn particular scrutiny for its suspected role in a growing list of systemic diseases, including Alzheimer's, diabetes, and certain cancers. It has previously been detected in the brain, liver, and placenta. But how it manages to take hold in the heart has been unclear. This study, published in Circulation, provides the first clear evidence that P. gingivalis in the gums can worm its way into the left atrium in both animal models and humans, pointing to a potential microbial pathway linking periodontitis to AFib.

The causal relationship between periodontitis and atrial fibrillation is still unknown, but the spread of periodontal bacteria through the bloodstream may connect these conditions."

Shunsuke Miyauchi, study first author, assistant professor at HU's Graduate School of Biomedical and Health Sciences

"Among various periodontal bacteria, P. gingivalis is highly pathogenic to periodontitis and some systemic diseases outside the oral cavity. In this study, we have addressed these two key questions: Does P. gingivalis translocate to the left atrium from the periodontitis lesion? And if so, does it induce the progression of atrial fibrosis and AFib?"

Read the full story here.

2025-05-10T14:31:42Z