Evidence Indicates Oral Pathogens May Help Trigger Stroke Events

Researchers at Tampere University in Finland have found the presence of DNA from oral pathogens in the cerebral emboli of stroke patients, signifying the possible adverse effects of suboptimal oral health. Findings from the study, “Oral Bacterial Signatures in Cerebral Thrombi of Patients With Acute Ischemic Stroke Treated With Thrombectomy,” published in the Journal of American Heart Association, focus on the connection between the oral/systemic link and overall wellness.

According to researchers, cerebral artery thrombosis causes 87% of strokes. The team analyzed thrombus aspirates removed from 75 stroke patients who received emergency treatment for acute ischemic stroke in the Acute Stroke Unit of Tampere University Hospital and found the majority of the aspirates contained pathogenic DNA, mainly from Streptococcus mitis. In addition to their role in the oral microbiota, once entering the circulatory system streptococcus bacteria act as pathogens that can cause infection of cardiac valves.

“Traditional risk factors for stroke are the same as those for coronary heart disease, and include hypertension, hypercholesterolemia, diabetes, smoking and obesity. Lack of control of these factors will inevitably increase the risk for stroke,” says Olli Patrakka, MD, a graduate student in the Department of Forensic Medicine at Tampere University. “Poor oral health also seems to be a risk factor.”

Among the 75 subjects who underwent thrombectomies, 84% of the blood clots tested positive for pathogenic DNA; of these, 79% had a strain of the streptococcus species, mainly the S. mitis group. Until additional research can further establish a link between oral pathogens and stroke, the authors emphasize oral health care as a primary preventive measure for atherothrombotic events.

From Decisions in Dentistry. September 2019;5(8):9.