Shingles and Stroke Risk
Study also found increased odds of heart attack, mini-stroke in older adults years after infection
By Serena Gordon
FRIDAY, Jan. 3, 2014 (HealthDay News) -- People who've had shingles -- a viral infection also known as herpes zoster -- before age 40 may have a higher risk of stroke years later, a large new study suggests.
Adults who get shingles after 40 don't have an increased risk of stroke. But along with those who had shingles before 40, they do have a higher risk of heart attack and "transient ischemic attack" (TIA), sometimes called a mini-stroke, the study authors said.
"In those aged less than 40 years at the time of herpes zoster, the risk of stroke, TIA and [heart attack] occurring in the years following was significantly higher than in [people without the infection]," said Dr. Judith Breuer, study lead author and a professor of virology and head of infection and immunity at University College London, in England.
"Herpes zoster is also more common in individuals who have risk factors for vascular disease, including diabetes and [high blood pressure]," Breuer said.
While the study found a link between shingles and higher stroke risk in younger adults, it didn't prove a cause-and-effect relationship.
Results of the study appeared online Jan. 2 in advance of publication in the Jan. 21 print issue of the journal Neurology.
Shingles is caused by the same virus that causes chickenpox. After someone has chickenpox, the virus stays in the body, lying dormant in the nerve roots, often for decades. It's not clear exactly why, but in some people, the virus reactivates and causes shingles, according to the U.S. Centers for Disease Control and Prevention.
People who have compromised immune systems are more likely to have shingles, according to the CDC. This includes people who have HIV and certain cancers, and people taking medications that suppress the immune system, such as those who've had an organ transplant.
Shingles causes a painful rash, usually on one side of the body. Pain, itching and tingling may occur before the rash appears.
Stroke risk is increased during a bout of shingles, according to background information in the study. But, Breuer and her colleagues wondered if the increased stroke risk lasted much longer than the shingles.
To answer that question, they reviewed more than 106,000 cases of shingles in the United Kingdom and compared them to more than 213,000 people who were matched for age and sex but hadn't had shingles. For those who'd had shingles, the average time since their illness was a little over six years. The longest time since shingles was 24 years.
The researchers controlled their analysis to account for other factors that could increase stroke and heart attack risk, such as smoking history, high blood pressure, unhealthy cholesterol levels, diabetes, heart problems and obesity.