Common Mouth Bacteria Linked to Heart Disease
Heart disease, unfortunately, tops the list as the leading cause of death worldwide, accounting for about 20 million fatalities each year. Recent research indicates that a familiar bacterium, residing in both the mouth and gut, might significantly influence heart health.
A research team in Finland examined fatty deposits, known as plaque, that can obstruct arteries and limit blood flow to the heart. They took samples from over 100 individuals who suffered heart attacks and another 100 who had undergone procedures to clear plaque from their arteries.
Upon analysis, they discovered the DNA of a specific bacterium—Viridians streptococcal—present in more than 40 percent of the plaque samples from both cohorts. This bacterium typically lives in the mouths of most Americans and is usually harmless in healthy individuals.
For the study participants, however, it appeared mostly as a biofilm, which is essentially a community of organisms that embeds itself in arterial walls. This biofilm can remain undetected by the immune system, lying dormant. But, in individuals with weakened immune systems or chronic health issues, these bacteria may break free from the biofilm, potentially leading to more severe conditions like endocarditis—a heart infection that can inflame and damage heart tissue.
When infected tissue dislodges from a heart valve, it can travel through the bloodstream and cause blockages in coronary arteries, ultimately resulting in a heart attack.
Given these findings, health experts are emphasizing the importance of good oral hygiene. Regular brushing and flossing, alongside routine dental check-ups, can help reduce the levels of Viridians streptococcal in the mouth.
Dr. Pekka J. Karhunen, a professor at Tampere University and one of the study’s authors, mentioned the goal of showing that a biofilm composed of different bacteria exists within atherosclerotic plaques. They are also considering whether the calcification process occurring in biofilms—similar to what’s seen on teeth—might also contribute to coronary artery calcification.
The study highlights a growing concern: nearly one in three Americans—around 83 million—are living with some form of cardiovascular disease, and predictions suggest that by 2050, over 60 percent of the population may face heart issues. In the U.S., cardiovascular diseases lead to about one in three deaths, translating to around one million lives lost annually.
In this particular study, which appeared in the Journal of the American Heart Association, researchers looked at coronary plaque samples from 121 individuals who experienced sudden cardiac deaths, with an average participant age of 63—mostly men.
A notable 66 percent of plaque samples from those who had died contained bacteria, while 58 percent from individuals who had plaque removal surgery also had bacterial presence. The Viridians streptococcal was the most common, detected in 42 percent of the deceased group and 43 percent of the surgery group.
Interestingly, normal arteries without significant blockages showed lower levels of bacteria. Dr. Karhunen mentioned that these oral bacteria often act as early colonizers in developing dental plaque. Thus, it is likely that the streptococci are not alone—there may be a biofilm made up of multiple bacteria.
While contained in the biofilm, bacteria are relatively safe within their jelly-like shield but can pose serious threats if activated through infections or other stimuli, potentially leading to inflammation and blood clots.
The potential complications of these bacteria could include endocarditis, which affects between 10,000 and 30,000 Americans yearly. This condition can create harmful clumps in the heart, which may break loose and lead to strokes or heart attacks.
While the findings aren’t conclusive, researchers are looking into developing a vaccine to counteract bacterial-induced biofilm formation. Dr. Elizabeth Klodas, chief medical officer of Step One Foods, emphasized that this research underscores how interconnected our bodily systems are, noting that proper dental care not only benefits oral health but also has implications for heart health.
