The traditional stroke symptoms are well known and include a sudden onset of numbness or weakness on one side of the body, trouble talking, loss of vision, or coordination problems.

But in women, doctors and bystanders should be paying attention to something else, says Lynda Lisabeth, Ph.D., MPH, researcher in the department of neurology at the University of Michigan Health System.

"What we're finding is that women experience what is considered non-traditional symptoms," said Lisabeth, who presented research findings on acute stroke symptoms at the 2009 International Stroke Conference this spring. "The non-traditional symptom that stood out was altered mental status, meaning confusion, disorientation or a loss of consciousness."

Symptoms such as sudden numbness of the face, arm or leg are a warning sign of what's happening in the body during a stroke which is a loss of blood supply to the brain because of a blocked or ruptured artery.

While larger scale studies focusing on stroke in women are warranted, the gender differences U-M researchers identified may contribute to delay in treatment for women and could signal a need to change public health campaigns, Lisabeth says.

The U-M study examined ischemic strokes, the kind experienced by 80 percent of stroke victims, and transient ischemic attack, called mini-strokes because symptoms go away quickly. Researchers examined the cases of 461 men and women and classified their symptoms as either traditional or non-traditional.

Altered mental status was the most common non-traditional symptom and it was more likely to be reported in women, the study showed. Researchers do not know why women's symptoms were different.

But the differences in symptoms may have consequences if slow recognition of stroke signs cause a delay in treatment, the researcher says.

"The only treatment that is currently FDA approved in the United States for stroke is tPA (tissue plasminogen activator), or what we call a clot-busting drug," Lisabeth says. "To administer tPA, people with stroke have to get to the hospital within three hours of symptom onset. So any delay on the part of actually getting to the hospital or delays once at the hospital could literally mean the difference between getting the therapy, or not getting the therapy."

Each year 800,000 Americans experience a stroke. Hispanic Americans and African Americans have a greater risk having a stroke, and to die from it. Intensive rehabilitation can help some overcome loss of function, but stroke remains a leading cause of disability. It is the third leading cause of death.

Men have an increased risk of stroke across most age groups. But in the oldest age groups, women's risk is higher, and since women live longer than men, women actually have an increased lifetime risk for stroke.

Several studies have suggested that women experience greater in-hospital delays such as longer triage times, longer time to see a physician and longer times to head imaging, which is critical for the diagnosis of stroke, compared with men, and have 30 percent lower odds of receiving tPA. Causes of these disparities are unclear, but could result from the different symptom presentation in women.

"We're hoping to understand those clinical implications and that information may lend itself to targeting stroke public health messages to women so that they can understand what it means to have one of these non-traditional stroke symptoms, and again emphasizing the urgency to seek care," says Lisabeth, who is also an assistant professor in the department of epidemiology in the U-M School of Public Health.

Recognizing an ischemic stroke

Strokes are a medical emergency, and if you notice one or more of these signs, don't wait. Call 9-1-1, or emergency medical services.

-- Sudden numbness or weakness of the face, arm or leg, especially on one side of the body;

-- Sudden confusion, trouble speaking or understanding

-- Sudden trouble seeing in one or both eyes

-- Sudden trouble walking, dizziness, loss of balance or coordination

-- Sudden severe headache with no known cause.

Source: University of Michigan Health System