Infections, Especially UTIs, May Be Triggers for Strokes
The study of over 190,000 stroke patients found that the risk of suffering a stroke was heightened in the weeks and months following any infection that required a trip to the hospital. But urinary tract infections (UTIs) showed the strongest link.
People were over five times more likely to suffer an ischemic stroke in the week following a UTI, versus the year before the infection, the findings showed.
Ischemic strokes -- the most common type of stroke -- are caused by a blood clot that diminishes blood flow to the brain.
The researchers said the findings do not implicate milder infections that people manage at home.
"We're probably capturing more-severe infections with this study," said senior researcher Dr. Mandip Dhamoon, an associate professor of neurology at Mount Sinai's Icahn School of Medicine, in New York City.
The study cannot prove that infections actually triggered strokes. But based on past research, Dhamoon said, it is biologically plausible: Infections can increase body-wide inflammation and may contribute to blood clots.
There are a lot of unknowns, though -- including whether certain treatments can not only clear a patient's infection, but also reduce the risk of a subsequent stroke. That's a question for future studies, Dhamoon said.
For now, people with risk factors for a stroke can focus on things they can control, according to Daniel Lackland, a professor of neurology at the Medical University of South Carolina.
"If you've recently been in the hospital for an infection, be even more cognizant of controlling your stroke risk factors, like high blood pressure and diabetes," said Lackland, who is also a spokesperson for the American Stroke Association.
The findings, published online June 27 in the journal Stroke, are based on more than 190,000 people who were treated for a stroke at New York State hospitals.
Most often, it was an ischemic stroke, but close to 40,000 patients had suffered a hemorrhagic stroke -- which occurs when a blood vessel ruptures and bleeds into the brain.
The researchers looked at each patient's risk of stroke in the week to four months after a hospital visit for an infection, and compared it with the risk in the previous year.
The risk gradually went down, but was still increased by twofold four months out, the investigators found.
At this point, Dhamoon said, it's not clear why UTIs would show the strongest association with stroke.
Respiratory infections, blood infections and UTIs were also tied to a heightened risk of intracerebral hemorrhage -- a type of hemorrhagic stroke. Why might infections contribute to brain bleeding? Effects on blood vessel function could potentially play a role, Dhamoon said. But that can't be discerned from this study, he added.
Another point: The study looked at people's stroke risk at a particular time in relation to another time period. So even though the risk was relatively elevated after an infection, that doesn't mean it was high.
"The absolute risk to any one patient is still probably low," Dhamoon said.
Past studies, Lackland said, have implicated certain infections as a possible stroke trigger -- including herpes zoster, which causes shingles.
"But this study suggests that a range of infections, if severe, are associated with stroke," Lackland said. That's important, he added, because it may help researchers figure out the "why."
© 2020 HealthDay. All rights reserved.
Posted: June 2019
Read this next
MONDAY, Oct. 19, 2020 -- A coronavirus strain that has plagued the swine industry in recent years may have the ability to spread to people, researchers say. Swine acute diarrhea...
THURSDAY, Oct. 15, 2020 -- Want to give your kids an immune system boost? Try letting them play in the dirt more often, a new study suggests. Researchers in Finland found that...
WEDNESDAY, Oct. 14, 2020 (American Heart Association News) -- It's flu season. In the middle of a coronavirus pandemic. Is this any time to be thinking about your risk of...
More News Resources
- FDA Medwatch Drug Alerts
- Daily MedNews
- News for Health Professionals
- New Drug Approvals
- New Drug Applications
- Drug Shortages
- Clinical Trial Results
- Generic Drug Approvals
- Monthly Update Archive
Subscribe to our Newsletter
Whatever your topic of interest, subscribe to our newsletters to get the best of Drugs.com in your inbox.