Fatal type of stroke most common in winter - HK study

HONG KONG, April 3 (Reuters) - A highly fatal type of stroke appears to occur more frequently during the coldest months of winter and when atmospheric pressure rises, doctors in Hong Kong have observed.

In an article published in the Hong Kong Medical Journal, researchers wrote such strokes, which are called aneurysmal subarachnoid haemorrhage, peaked in January.

"It is the most fatal type of brain haemorrhage, with a mortality of 50 percent," said George Wong, associate professor at the Prince of Wales Hospital's neurosurgery division.

Those who do not survive usually die on the day of the stroke, Wong said.

Wong and his colleagues studied records of 135 patients who suffered this form of stroke from October 2002 to October 2006, and found that most of the strokes occurred in winter.

"The incidence is higher in winter, which correlates with changes in atmospheric pressure," Wong told Reuters.

Wong's team will try to find out the actual processes that changes in atmospheric pressure trigger in the human brain, but he said it may have to do with blood pressure change.

"It (such a stroke) is more common in patients with hypertension and smokers," he said.

"The two messages we want to bring out are for people to be more aware of weather conditions and for people to control their blood pressure and, of course, quit smoking." (Reporting by Tan Ee Lyn; Editing by Sugita Katyal)