Having shingles, especially when you are younger, may increase your risk of having a stroke or heart attack later in life, according to a new study published this week in the online issue of Neurology.

Shingles is caused by the varicella zoster virus, according to the Centers for Disease Control and Prevention. It's the same virus that causes chickenpox. Also called herpes zoster, shingles appears as a painful rash, which in some cases can lead to further infection if left untreated. Doctors say the virus remains dormant in the nerve roots of people who have had chickenpox; anyone who has the virus as a child may develop an outbreak of shingles later on.

In this study, British researchers looked at more than 105,000 people who had had shingles and more than 213,000 people who had not. They found people aged 18 to 40 who had shingles were more likely to have a stroke, warning stroke (also known as a transient ischemic attack), or heart attack later in life.



The data showed people under 40 years old were 74% more likely to have a stroke if they had shingles, after adjusting for other stroke risk factors such as smoking, high cholesterol and obesity. The research also pointed out that patients under 40 were 2.4 times more likely to have a warning stroke if they had shingles and 50% more likely to have a heart attack. In those over 40 who had shingles, the risk was not as great; patients were 15% more likely to have a warning stroke and 10% more likely to have a heart attack.

“Anyone with shingles, and especially younger people, should be screened for stroke risk factors,” said lead study author Dr. Judith Breuer.

This is not the first study to look at the link between shingles and stroke/heart attack risk.

For example, in an October 2009 issue of the American Heart Association’s journal Stroke, a study found adults with shingles were at an increased risk for stroke, especially if they had shingles that affected the eyes.

Compared to adults without shingles, those with the painful skin rash were about 30% more likely to suffer a stroke within a year of the attack. Patients who had shingles in and around an eye had four times the risk for stroke in the year following the episode.

"Many studies have shown that people with herpes zoster infection are more likely to develop stroke.," said lead author, Dr Jiunn-Horng Kang, attending physician in the Department of Physical Medicine and Rehabilitation at Taipei Medical University Hospital. "But ours was the first to demonstrate the actual risk of stroke following herpes zoster infection."

For some doctors, these findings on the shingles virus and its relationship to stroke raise red flags.

“Although it’s still unknown why herpes zoster can cause stroke and heart problems, I am guessing it highlights the role of viral infections, like shingles and the cause of inflammation to the circulatory system,” explains Dr. Warren Levy, a cardiologist and chief medical officer at Virginia Heart in Northern Virginia. “We already know inflammation can cause serious heart problems. Perhaps we need to be extremely vigilant, especially with those who have been infected with shingles, and treat them more aggressively for heart attack and stroke prevention, no matter what age they became infected.”

Levy also brings up an interesting point: Shingles is considered to be a virus that primarily infects the elderly. In fact, the herpes zoster vaccine, designed to prevent shingles, is recommended for those over the age of 60. But these latest findings point to even greater risks of heart problems for those who contract shingles earlier in life. So the question remains, "Should younger people be getting the vaccine?"

“The shingles vaccine has been shown to reduce the number of cases of shingles by about 50%,” notes Breuer. “Studies are needed to determine whether vaccination can also reduce the incidence of stroke and heart attack."