The risk of a stroke is increased by a third in patients already suffering from shingles, according to the American Heart Association journal Stroke.
And it reports that if the infection involves the skin around the eye, or the eye itself, the risk is more than four times greater
Shingles leads to a three-fold jump in the risk of haemorrhagic, or “bleeding”, strokes, as well as the more common ischaemic strokes, caused by a blocked arteries.
Scientists studied 7,760 adults who had been treated for shingles between 1997 and 2001 and more than 23,000 matched “control” individuals with no history of the infection. Over the course of a year, 133 of the shingles patients and 306 of the controls had a stroke.
Dr Jiunn-Horng Kang, from Taipei Medical University Hospital in Taiwan said: “While the mechanism by which shingles increases stroke risk remains unclear, the possibility of developing a stroke after a shingles attack should not be overlooked.
“Doctors and patients must pay extra attention to controlling other risk factors for stroke, such as high blood pressure, smoking and diabetes.”