The discovery could lead to new methods of treating or preventing stroke

Artist’s impression of human gut bacteria in the large intestine

Bacteria found within the human gut may play an important role in stroke, a study carried out in Barcelona, Spain, has found.

According to the Stroke Association, stroke is a leading cause of death in the UK, with one person affected every five minutes. Of these, ischaemic strokes are the most common and occur when a blood clot blocks the flow of blood and oxygen to the brain. These clots usually build up in areas where the arteries have become narrowed by fatty deposits known as plaques.

“The influence of the gut microbiome – the trillions of bacteria and other microorganisms that live in the gut – is a modifiable risk factor associated with the risk of stroke and with post-stroke neurological outcomes.

However, most research has previously been done in animal models,” said lead author Dr Miquel Lledós.

In the new study, researchers from the Sant Pau Research Institute Stroke Pharmacogenomics and Genetics Laboratory took faecal samples from 89 participants who had suffered from ischaemic strokes and compared them to samples taken from a healthy control group. They found that several types of gut bacteria were linked to an increased risk of stroke. Two others were linked to more severe symptoms in the 24 hours following a stroke.

At least one other was linked to a poorer neurological recovery in the three months following a stroke.

The researchers hope that their findings can lead to the development of new treatments, which use the microbiome to prevent stroke and improve recovery.