May 22, 2003 -- One of the most deadly types of stroke may actually be preventable among the young and middle-age people it most frequently strikes. A new study suggests that lifestyle changes like quitting smoking, avoiding illicit drug use, and getting high blood pressure under control can substantially reduce the risk of subarachnoid hemorrhage, or bleeding strokes.
Researchers say subarachnoid hemorrhage accounts for only about 3% of all strokes, but it is among the most deadly types of stroke. SAH occurs when a blood vessel on the brain's surface ruptures and bleeds into the space that surrounds the brain. The resulting strokes often happen without warning and are fatal in up to 50% of all cases.
To see what factors might increase the risk of subarachnoid hemorrhage, the study compared lifestyle and health factors among a group of 312 people between the ages of 18 and 49 who had this type of bleeding stroke to a similar group of 618 healthy adults. The results appear in the May 23 issue of the Stroke: Journal of the American Heart Association.
Researchers found major differences between the two groups. Those who had suffered a subarachnoid hemorrhage were much more likely to be smokers, have high blood pressure, or have used cocaine in the last three days than the others.
"One of the study's key findings is that two-thirds of the people who had a subarachnoid hemorrhage in this age group were current cigarette smokers. That is a huge number," says researcher Joseph P. Broderick, MD, professor of neurology at the University of Cincinnati in Ohio, in a news release. "If you're a smoker in this age group, you are about 3.7 times more likely to have this type of stroke than if you're not a smoker."
Researchers say this is also the first study to link cocaine use to an increased risk of bleeding stroke. Although only 3% of stroke victims reported cocaine use, none of the people in the healthy comparison group had used cocaine.
"There is also a familial tendency for this type of stroke," says Broderick. "People in the study who had [subarachnoid hemorrhage] were about 3.8 times more likely than controls to have a family member who had bleeding stroke."
Other factors linked to a higher risk of subarachnoid hemorrhage were being thinner and having lower body mass index (BMI), use of pharmaceutical products containing caffeine and nicotine, and having a lower educational status.
Researchers say these risk factors need to be studied more, but the results of the study should give people, especially those with a family history of bleeding stroke, even more reason to take better care of themselves and make healthy lifestyle changes.