Heart attack and stroke risk may rise briefly after a bout of shingles

A painful, blistering rash known as shingles may temporarily increase a person's risk of a stroke or heart attack, according to a study in the Dec. 15, 2015 PLOS Medicine. Also known as herpes zoster, shingles results from a reactivation of the virus that causes chickenpox, which most adults had during childhood.

For the study, researchers analyzed the records of more than 67,000 people ages 65 and older diagnosed with shingles and either a heart attack or stroke from 2006 through 2011. They then compared the rates of cardiovascular events before and after a shingles attack. In the first week after a shingles diagnosis, the risk of a stroke rose 2.4 times and the risk of a heart attack increased 1.7 times compared with baseline risk.

About one in three people in the United States will develop shingles at some point. Experts recommend that people 60 and older receive a vaccine against shingles. But only 9% of the study participants had done so—not enough to determine if the vaccine could affect the risk of cardiovascular problems.

Other infections, including influenza and pneumonia, have also been linked to a transient increase in cardiovascular events. The authors postulate that the body's natural response to infections may promote inflammation. The resulting unhealthy changes in the arteries may trigger blood clots that can lead to a stroke or heart attack.