Oral bacteria associated with increased risk of stroke

In a recent study published this month in Scientific Reports, researchers at the University of Louisville School of Medicine have increased their understanding of an association between different types of stroke and the presence of the oral bacteria, Streptococcus mutans.

Oral infectious diseases have been previously associated with stroke. Strokes are defined as either ischemic (a blockage of one or more blood vessels supplying the brain) or hemorrhagic strokes (blood vessels in the brain rupture). Small vessel diseases are important biomarkers of vascular injury and brain dysfunction.

In this study, researchers observed 100 acute stroke patients to better understand the relationship between hemorrhagic stroke and oral bacteria. In the patients who experienced intracerebral hemorrhage (ICH), 26% were found to have cmn-positive S. mutans in the saliva. Among patients with other types of stroke, only 6% tested positive. Researchers found that the cmn-positive S. mutans contributes to the development of intracerebral hemorrhage by expressing a collagen-binding protein that the cnm gene encodes on the bacterial surface which disrupts the blood-brain barrier. S. mutans is a major pathogen of dental caries and causes bacteremia by dental procedures.

The researchers also evaluated MRIs of the participants for the presence of cerebral microbleeds (CMB), which are small brain hemorrhages that may cause dementia and also often underlie ICH. They found that the number of cerebral microbleeds (CMBs) were significantly higher in subjects with cnm-positive S. mutans than in those without.

They believe the S. mutans bacteria may bind to blood vessels weakened by age and high blood pressure and cause arterial ruptures in the brain leading to hemorrhages. This may explain the cause of the inflammation and endothelial damage.

This study demonstrates a possible mechanism by which cnm-positive S. mutans induces hemorrhagic changes in perforating arterioles and the importance of oral health and its role in brain health. It is essential to have good oral hygiene because it impacts the rest of the body.

Multiple research studies have shown a close association between gum disease and heart disease as well as increasing the severity of rheumatoid arthritis.

The cnm-negative S. mutans bacteria is found in approximately 10% of the population, which is known to cause dental caries. They are also researching the role of oral bacteria in other neurodegenerative disorders such as Alzheimer’s and Parkinson’s disease.

Silver and Dental-Lac should be considered for overall oral health. Silver is a highly effective antimicrobial that can be used as a broad-spectrum antimicrobial before, during, and after dental procedures. It supports the immune system, has no side effects, and does not interfere with antibiotics. Dental-Lac is a patent pending and clinically tested specific Lactobacillus paracasei strain that has been show to kill off harmful strains of harmful bacteria including S. mutans.

By Michael Jurgelewicz, DC, DACBN, DCBCN

Source: Shuichi Tonomura, Masafumi Ihara, Tomohiro Kawano, Tomotaka Tanaka, Yoshinori Okuno, Satoshi Saito, Robert P. Friedland, Nagato Kuriyama, Ryota Nomura, Yoshiyuki Watanabe, Kazuhiko Nakano, Kazunori Toyoda, Kazuyuki Nagatsuka. Intracerebral hemorrhage and deep microbleeds associated with cnm-positive Streptococcus mutans; a hospital cohort study. Scientific Reports, 2016; 6: 20074 DOI: 10.1038/srep20074