Stroke Risk Spikes After Shingles Episode: Study
But getting antiviral meds to treat painful rash lowers chances of brain attack, researchers add
The virus can invade the walls of blood vessels, infecting the cells and increasing the chance that a vessel could clog or rupture, Nagel said.
That's likely the reason why stroke risk is so pronounced in people with shingles around their eyes -- from that location, the reactivated virus has a direct pathway into the arteries of the brain, she said.
Shingles also promotes inflammation in the body, which can cause arterial plaques to rupture and induce a stroke.
The new study involved 6,584 stroke victims who also suffered from shingles, drawing from a database of information of patients in over 600 general practices in the United Kingdom.
Researchers compared the risk of stroke in the time period after the patient had shingles to earlier times when the patient did not have shingles.
The investigators found the stroke rate was 63 percent higher in the first four weeks after a shingles episode compared to the patient's baseline risk. The risk then diminished slowly over time, dropping to 42 percent in weeks 5 through 12 and then to 23 percent for up to 6 months later.
Treatment with oral antiviral medication significantly reduced this risk, the results showed. Researchers found that shingles patients who were not treated with antivirals had nearly double the stroke risk of those who received the medication.
Dr. Larry Goldstein, director of the Duke University Stroke Center, said people who have contracted shingles should talk with their doctor about going on an antiviral medication.
"If somebody has an outbreak, there's no downside to seeking antiviral treatment," said Goldstein, who's also a spokesman for the American Heart Association.
Langan and Nagel both hope the findings will help promote vaccination for shingles among seniors.
The U.S. Centers for Disease Control and Prevention recommends that everyone 60 or older get the vaccine. It is covered by Medicare's prescription drug plan, and most private plans also cover the shot.
"One-third of patients who get stroke from varicella zoster virus do not get a shingles rash," Nagel said. "We can prevent those strokes by getting people vaccinated."