Shingles May Raise Risk of Stroke

Adults with shingles are at increased risk for stroke,
especially if they have shingles that affects the eyes, a study shows.

The study is not the first to show an elevated stroke risk associated with
shingles, but it is the first to quantify the risk, researchers say.

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.

"If a person is already at risk for stroke, they should be aware that their
risk may be higher if they have had shingles," study researcher Jiunn-Horng
Kang, MD, MSc, tells WebMD.

Also known as herpes zoster, shingles is caused by the varicella-zoster
virus (VZV) -- the same virus that causes chickenpox.

Anyone who has had chickenpox in childhood can develop shingles at some
point in their lives.

In many people, the virus remains dormant in nerves. But in some, especially
older people and those with compromised immune systems, it can reactivate as
shingles.

The reawakened virus initially causes numbness, itching, severe pain, and
even fever, headaches, and chills, followed by the blistering rash
characteristic of shingles. The skin rash usually occurs within three to five
days after symptoms begin.

Shingles can result in persistent pain lasting for months and even years
after the rash has gone away.

The newly published study included nearly 8,000 adults treated for shingles
between 1997 and 2001 and about 23,000 people matched for age and sex who had
no history of shingles or stroke before 2001.

During the year following the shingles episode, 133 shingles patients (1.7%)
and 306 people in the comparison group (1.3%) had strokes.

The shingles patients had a 31% increased risk for strokes of any kind and a
nearly threefold increased risk for hemorrhagic strokes.

Hemorrhagic strokes, caused by bleeding in the brain, are much less common
than ischemic strokes, which are caused by blocked arteries. Only about 10% to
15% of strokes involve brain bleeds.

Patients with shingles involving the skin around the eye and the eye itself
were 4.28 times more likely to have a stroke than were people without
shingles.

The study was published online today and will appear in the November issue
of the American Heart Association journal Stroke.

Stress, Inflammation May Play Role

Varicella zoster virus-related blood vessel damage has been linked to stroke
after shingles attacks, but this did not fully explain the high stroke risk
seen in the study, Kang and colleagues wrote.

They added that the stress associated with shingles and the intense pain
that can occur with outbreaks and following them could play a role, as could
the inflammation that occurs with shingles outbreaks.

American Stroke Association spokesman Daniel Lackland, MD, says shingles
patients and their doctors need to be aware of the new research.

Lackland is a professor of epidemiology and medicine at the Medical
University of South Carolina in Charleston.

"This research needs to be confirmed, but it may be that shingles patients
with risk factors for stroke need more aggressive monitoring and treatment than
the average patient," he tells WebMD.

But he adds that the shingles-related stroke risk identified in the study is
nowhere near as great as the risk associated with better-established stroke
risk factors, like high blood pressure.

"The message doesn't change based on this study," he says. "Getting high
blood pressure under control and treating other modifiable risk factors is what
we have to focus on."

Early, aggressive treatment with antiviral drugs can lessen the length and
severity of shingles attacks.

Kang says it remains to be seen if aggressive antiviral treatment can also
lower sroke risk.

"This is a question we need to study," he says.

By Salynn Boyles
Reviewed by Louise Chang
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