To arrive at this finding, researchers at University College London scoured existing patient medical records looking for patterns between shingles and cardiovascular disease.
After factoring in other conditions, they determined that herpes zoster – the virus associated with shingles – is an independent risk factor for heart attack.
Scientists think that the increased risk might lie in chronic inflammation of blood vessels, which shingles causes.
The study, published in Neurology, also found that major stroke risk increased in patients who had shingles at or under the age of 40.
Shingles not a cause of heart attacks, mini-strokes
It’s important to note that the findings do not suggest that shingles actually causes heart attacks, says Benico Barzilai, MD, Head of the Section of Clinical Cardiology in the Robert and Suzanne Tomsich Department of Cardiovascular Medicine at Cleveland Clinic. He did not take part in the study, but reviewed the results.
“The UK study raised interesting questions that do warrant further study, but it doesn’t say that shingles causes heart attacks, because the relationship found is an association, not cause and effect,” he says.
This means that while researchers did find a relationship between shingles and these cardiovascular events, they did not find data to support shingles as a direct cause of them, an important distinction.
Who should get the shingles vaccine
Experts say people age 60 and older should ask their doctor about the shingles vaccine. This is keeping with current Centers for Disease Control (CDC) recommendations.
“Generally, young and middle-aged adults don’t need vaccination,” Dr. Barzilai says.
Andrea Sikon, MD, Chair of the Department of Internal Medicine and Geriatrics in the Medicine Institute at Cleveland Clinic, explains current guidelines: “The vaccine is approved for use at age 50, but the optimal time to vaccinate might not be that early, as effectiveness may wane over time.”
Exceptions and warnings
Not everyone age 60 and older should receive the vaccine because it can be dangerous for people with some pre-existing conditions.
Drs. Barzilai and Sikon both stress that the vaccine can be dangerous for cancer patients, transplant patients, patients with HIV and those on medications that supress their immune system, such as systemic steroids and chemotherapy, among others.
This is because the herpes zoster vaccine contains a live, attenuated (weakened) virus. Doctors must carefully assess the health status of each patient before administering it.
The chicken pox-shingles connection
The same virus that causes chicken pox (varicella) also causes shingles. Even after symptoms of chicken pox disappear, the varicella virus stays put in the body, lying dormant until later in life when it can reassert itself.
Anyone who had chicken pox or the vaccine against it, which is typically in childhood, can develop shingles later in life.
Typically, shingles causes a rash and painful blisters on the legs, arms or all over the body. In some cases, pain can linger for months or even years after other symptoms subside.