Shingles Raises Risk Of Stroke

(October 15, 2009) - Shingles (Read about "Shingles") is painful enough, but now a new study says it also raises your risk of stroke. (Read about "Stroke") Adults with shingles were about 30 percent more likely to have a stroke during a one-year follow-up than adults without shingles, in a study reported in Stroke: Journal of the American Heart Association. The risk was even greater when the infection involved the eyes.

Shingles, also called herpes zoster, is a painful skin rash caused by the varicella zoster virus (VZV). VZV is the same virus that causes chickenpox. (Read about "Childhood Illnesses") After a person recovers from chickenpox, the virus stays in the body. Usually the virus doesn't cause problems, but it can reappear years later, causing shingles.

"Many studies have shown that people with herpes zoster infection are more likely to develop stroke. But ours is the first to demonstrate the actual risk of stroke following herpes zoster infection," said Jiunn-Horng Kang, M.D., M.Sc., lead author of the study.

Kang and his associates studied 7,760 patients 18 years and older who received shingles treatment. These people were matched by age and gender with 23,280 adults who weren't treated for shingles (controls). Their average age was 47. Researchers found:

• People treated for a shingles infection were 31 percent more likely to have a stroke, compared with patients without a shingles infection.
• Patients with shingles infections that involved the skin around the eye and the eye itself (herpes zoster ophthalmicus) were 4.28 times more likely to have a stroke than patients without shingles. When the researchers analyzed the risk of stroke by stroke type, they found:
• Shingles patients were 31 percent more likely to develop an ischemic stroke during the one-year follow-up than those without shingles.
• The risk of hemorrhagic (bleeding) stroke was 2.79 times higher for people with shingles infection than for people without shingles.

Ischemic strokes, which are caused by the blockage of an artery, account for 87 percent of the new or recurrent strokes that strike about 780,000 Americans annually, according to the American Heart Association.

"Herpes zoster infection is very easy to diagnose, and antiviral medication can be used to treat the infection in the early stages," Kang said. "While the mechanism by which shingles increases stroke risk remains unclear, the possibility of developing a stroke after a shingles attack should not be overlooked."