Gut Bacteria Linked to Stroke Severity, Risk
Kelli Whitlock Burton
Two new studies identifying strains of gut microbiota associated with more severe strokes and worse post-stroke recovery point to a possible role for the gut microbiome in preventing stroke and improving outcomes.
Researchers identified gut microbiota that were different in stroke patients compared to control persons, including more than two dozen bacteria associated with a range of stroke subtypes and strains specifically associated with worse stroke severity 6 hours and 24 hours after the event.
The findings add to a growing body of evidence that researchers say could eventually lead to therapies to improve stroke outcomes.
“There are no specific neuroprotective treatments to prevent neurological worsening after stroke,” Miquel Lledós, MSc, a doctoral student at Stroke Pharmacogenomics and Genetics Laboratory at the Sant Pau Research Institute, Barcelona, Spain, who led one of the studies, told Medscape Medical News. “The use of new therapies such as changes in the microbiome through nutritional changes or fecal transplantation could be useful to improve post-stroke evolution or to decrease stroke risk.”
The findings were presented at the European Stroke Organisation Conference (ESOC) 2022 on May 4.
A Role for Gut Bacteria?
Gut microbiota have been implicated in dementia risk, cardiovascular disease, and multiple sclerosis relapse. Prior research has also pointed to a possible link between gut bacteria and stroke. Emerging evidence suggests a possible link between gut bacteria and stroke risk, although most work so far has been conducted in animal models.
“In humans, the role of the intestinal microbiota and its relationship with neurological evolution and post-stroke disability are beginning to be analyzed,” Lledós said. He said their main goal was “to identify if the gut microbiota was associated with the neurological outcome in the acute phase and functional recovery at 3 months after stroke.”
For their study, Lledós and colleagues analyzed microbiota in the first fecal samples from 89 patients following an ischemic stroke. They compared the results to those from 12 control persons.
After adjusting for age, sex, stroke subtype, and other confounders, they identified multiple taxa associated with ischemic stroke risk (Fusobacterium, P = 1.40×10-6, ß = 2.62) and confirmed others that had previously been identified (Lactobacillus, P = 4.27×10-11, ß = 3.40).
Researchers further identified new taxa associated with higher risk of stroke severity in the acute phase at 6 hours (Prevotella copri, Negativibacillus) and at 24 hours (Lentisphaeria). They also identified one class (Kiritimatiellae), one genus (Acidaminococcus), and one species (Paraprevotella xylaniphila) that are related to poor functional outcome 3 months after ischemic stroke.