Adults with the skin disease shingles appear to be at an increased risk for stroke, especially when it affects the area around the eyes, researchers report.
Previous reports have linked shingles with stroke risk, but the exact frequency and risk for these phenomena are still unknown," said study lead author Jiunn-Horng Kang, MD, a principal investigator in the Neuroscience Research Center of Taipei Medical University Hospital, Taiwan. His team published their findings in the journal Stroke.
Shingles is a painful skin rash resulting from infection by the varicella-zoster virus, the same virus that causes chicken pox. The virus remains in the body after recovery from chicken pox and can erupt again to cause shingles.
Shingles usually starts as a rash on one side of the face or body, and often causes pain, itching and tingling. Attacks can last for two to four weeks. The incidence of shingles increases with age, and the US Centers for Disease Control and Prevention recommends most people over age 60 be vaccinated against the virus, with the major exception being those with weakened immune systems.
Dr. Kang and his colleagues studied data on 7,760 adult Taiwanese who were treated for shingles between 1997 and 2001. In the year af ter treatment, 133 of them, or 1.7%, had strokes. The incidence in a control group of 23,280 adults who were not treated for shingles was 1.3% (306 people).
Analysis of the data found that the risk of stroke in that one-year period was 31% higher in the shingles group. The incidence was dramatically higher for those with a shingles infection in or around the eye-nearly 4.3 times higher than in the control group.
Strokes can be ischemic, caused by a blood clot blocking a brain artery, or hemorrhagic, due to rupture of a blood vessel. The study found a 31% higher incidence of ischemic strokes, the most common kind, and a 2.79-times higher incidence of hemorrhagic stroke in the shingles group.
"The major mechanism of our findings is that stroke results from herpes zoster virus-induced vasculopathy (blood vessel damage)," Dr. Kang said. "The vessel to the brain damaged by the virus could be occluded [blocked) or ruptured."
"However, several other factors could also be involved," he added.
No known treatment exists to reduce the apparent risk of stroke that results from shingles infection, Dr. Kang said. "Our interest and ongoing research are focused on whether early antiviral treatment for herpes zoster can reduce the risk of stroke," he said. Also, patients who have a shingles attack should be aware of the risk of stroke, and talk to their doctor about managing risk factors for stroke, such as hypertension, high cholesterol and diabetes, said Dr. Kang.
While there have been scattered reports about a possible association of shingles with stroke, "to my knowledge this is the first study to link shingles very specifically with stroke," said Daniel Lackland, MD, professor of epidemiology and medicine at the Medical University of South Carolina, and a spokesman for the American Stroke Association.
"It might be a little too early for a lot of clinical implications here," Dr. Lackland said. “But a physician who is treating someone with shingles should emphasize the importance of traditional risk factors for stroke, and let the patient know that your risk might be a little bit increased and you should pay more attention to high blood pressure, cholesterol and the like."
Better Stroke Risk Predictor
To determine which patients need drugs and/or lifestyle changes to reduce stroke risk, doctors consider blood pressure, blood sugar, cholesterol, weight, exercise, cigarette use and family history.
New: Patients thought to be at intermediate risk for stroke were more accurately classified as high risk or low risk when assessment also included blood tests for two inflammation markers, C-reactive protein (CRP) and lipoprotein-associated phospholipase A2 (LP-PLA2).
Best: Ask your doctor whether you should have CRP and Lp-PLA2 measured.