Three-quarters of young American adults are unaware of, or underestimate, the urgency of stroke symptoms and would delay going to the hospital for treatment, a survey indicates.

Victims of ischemic stroke, where blood flowing to a person's brain is blocked, have the best chance of having that flow restored and minimizing or reversing stroke damage if they receive treatment in the first three hours after symptoms arise. This is what doctors call the "golden window" for medical intervention, researchers at the Ronald Reagan UCLA Medical Center say.

"Timely treatment for stroke is probably more important than for almost any other medical problem there is," says Dr. David Liebeskind, a neurology professor and director at the center's Neurovascular Imaging Research Core. "There is a very limited window in which to start treatment because the brain is very sensitive to a lack of blood flow or to bleeding, and the longer patients wait, the more devastating the consequences."

A nationwide survey with around a thousand interviews asked people what they thought they would do in those first three hours if they had numbness, weakness or difficulty in speaking or seeing — common stroke symptoms.

Only about a third of those younger than 45 responded that they would consider going to a hospital, and a full 73 percent said they would probably just wait and see whether the symptoms eased or improved.

Those are not encouraging numbers, says Leibeskind.

"That's a real problem," he says. "We need to educate younger people about the symptoms of stroke and convince them of the urgency of the situation, because the numbers are going up."

Since the 1990s, strokes in younger patients under the age of 45 have increased by more than 50 percent, the researchers note.

Ischemic stroke, often linked to high blood pressure, obesity, diabetes and smoking, can strike anyone at any age, they point out.

"The good news is, there are steps we can take to lower our risk of stroke," says Liebeskind, citing regular exercise, healthy diet, limiting alcohol and avoiding smoking as way to reduce the risk of suffering a stroke.

If symptoms do occur, however, time is of the essence, he emphasizes.

"Believe it or not, it's on the order of minutes or hours when somebody has to seek medical attention," he says. "There simply is no time to wait. It's a message that we clearly need to get to younger people more effectively."