Is death lurking in your mouth?

Scientist find link between mouth bacteria and stroke

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Scientists find traces of mouth bacteria DNA in the blood clots from stoke victims.


IF YOU ever needed more encouragement to brush the pearly whites or soak the dentures, a new study suggests good oral hygiene might help protect against stroke?

Finnish scientists have found traces of the DNA of oral bacteria in samples of blood clots that had caused strokes leading them to believe there may be a link.

The researchers from Tampere University analyzed clot samples from 75 people who received emergency treatment for ischemic stroke.

The patients had undergone thrombectomies. These procedures remove blood clots by means of catheters conducted through arteries. The catheters can deploy stent retrievers and aspirators to reduce or remove the clot.

When they analyzed the blood clots sampled in this way, the researchers found that 79 per cent of them bore DNA from common oral bacteria. Most of the bacteria were of the streptococcus mitis type, which belong to a group that scientists call viridans streptococci.

The levels of the oral bacteria were much higher in the blood clot samples than they were in other samples that surgeons took from the same patients.

The study forms part of a large investigation that Tampere University has been conducting for around 10 years on the role of bacteria in cardiovascular diseases.

This investigation has already found that blood clots that have caused heart attacks, brain aneurysms, and thromboses in leg veins and arteries, contain oral bacteria, particularly viridans streptococci. It has also shown that these bacteria can cause infective endocarditis, a type of heart infection.

The researchers believe that the new study is the first to implicate viridans streptococci in acute ischemic stroke.

What is a stroke?

A stroke is when the brain suddenly experiences a disruption to its blood supply. This starves cells of essential oxygen and nutrients and can result in tissue damage and loss of function in the brain.

The most common type of stroke is an ischemic stroke, which occurs when a blood clot reduces the blood supply in an artery that feeds the brain.

According to figures from the World Stroke Organization, around one in six people worldwide will likely experience a stroke in their lifetime.

One of the leading causes of stroke is a condition called atherosclerosis in which plaques form in the walls of arteries and cause them to narrow and harden over time. The plaques are deposits of cellular waste, fat, cholesterol, and other materials.

Depending on where the plaques form, atherosclerosis can raise the risk of heart disease, angina, carotid artery disease, and peripheral artery disease.

However, plaques can also lose bits into the bloodstream, or attract clots. If such an event affects an artery supplying blood to the brain, it can trigger an ischemic stroke.

The team reports the findings in a recent Journal of the American Heart Association.

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If you believe someone may be having a stroke remember FAST

Face: Check their face. Has their mouth drooped?

Arms: Can they lift both arms?

Speech: Is their speech slurred? Do they understand you?

Time: Is critical. If you see any of these signs call 000 straight away.