Newswise — Mexican Americans and women may be at higher risk for subarachnoid hemorrhage, a type of stroke involving bleeding in the space around the brain, according to a study published in the June 11, 2008, online issue of Neurology®, the medical journal of the American Academy of Neurology.

People with this type of bleeding in the brain may have a severe or "thunderclap" headache that is sometimes described as the worst headache of a person's life. Other symptoms that may accompany the headache include vomiting, seizures and neck stiffness. The condition is usually caused by a cerebral aneurysm, a blistering of a blood vessel, and can lead to death or severe disability even when caught early.

For the study, researchers reviewed the medical records of 29,907 people in southeast Texas and identified 107 people age 44 and older who had experienced a subarachnoid hemorrhage over seven years. Of those, 43 were white and 64 were Mexican American. Sixty-seven percent were women.

The results showed that Mexican Americans were one and two-thirds times more likely to have a subarachnoid hemorrhage than white people. Women in the study had a one and three-quarters-fold increased risk of having this type of stroke.

"Physicians and public health officials should help Mexican Americans and women take steps which might prevent subarachnoid hemorrhage," said study author Lewis B. Morgenstern, MD, Professor and Director of the University of Michigan Stroke Program in Ann Arbor and Fellow of the American Academy of Neurology. "Given that Mexican Americans account for the largest and fastest-growing minority group in the United States, it is important to examine how this condition may affect certain ethnicities differently."

Morgenstern says differences in tobacco use and the treatment of hypertension between ethnic groups may have played a role in the study's outcome. He also cautions that the study took place in one geographic area, so results may not be the same in other locations.

The study was supported by the National Institutes of Neurological Disorders and Stroke.

The American Academy of Neurology, an association of more than 21,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as epilepsy, dystonia, migraine, Huntington's disease, and dementia. For more information about the American Academy of Neurology, visit http://www.aan.com.