CHICAGO (NewsNation Now) — World Stroke Day is Thursday, but the disease affects more than 13 million people worldwide, according to the World Stroke Organization.

Stroke is the fifth leading cause of death in the U.S. and the leading cause of long-term disability. In fact, strokes are so common, 1 in 4 people will experience a stroke in their lifetime, according to the American Heart and Stroke Association.

How common are strokes?

“There are about 800,000 strokes a year in the United States and if you look at people of all ages over the course of their lifetime about a quarter of people will go on to experience a stroke sometime in their lives,” said Dr. Mitchell Elkind, president, American Heart Association said.

What causes a stroke?

“There are two major kind of stroke,” Dr. Elkind said. “One is caused by a blockage in the blood vessel called an ischemic stroke and the other less common kind is when the blood vessel bursts and then there’s bleeding into the brain so there’s either ischemic or hemorrhagic stroke.”

What are the warning signs of a stroke?

“What people should know the most common signs of symptoms of a stroke I like to use the acronym F.A.S.T. which stands for face drooping, arm weakness, speech difficulty, then it’s T, time to call 9-1-1,” Elkind said. “We like to say time is brain. So the longer the brain goes without oxygen, nutrients, because of a blockage in the blood vessels the more likely there is to be damage and a greater degree of damage and more serious muscle function and deficits after the stroke. It wasn’t that long ago that we didn’t have any way of treating strokes maybe in the last 20 years we’ve been able to treat strokes with clot-busting medications but we have to give those within three hours ideally, maybe a little bit longer than that in some patients.”

High blood pressure rates we know are on the rise in fact the surgeon general has issued a call to action regarding high blood pressure. Why do you think these rates are increasing?

“We’ve learned that it’s important to have your blood pressure below 120 over 80. Beyond that it’s also partly due to the fact that not everybody has access to medical care, not everybody gets their blood pressure screened or tested by a primary doctor,” Dr. Elkind said. “The other very important issue is our lifestyle. We know that getting enough exercise, eating right, limiting sodium or salt in the diet for example, all of these things are very important also in controlling blood pressure.”

What is the biggest misconception do you think or are there several about strokes?

“One of them is that strokes only happen to older people, and we know that’s not true. We have actually seen in the last few years that there’s been some increase in stroke in young people, meaning people in their 20’s, 30’s, 40’s,” Dr. Elkind said.

He added, “You know it’s not only a disease of the elderly. I would say the other major myth about stroke is there’s nothing you can do about it, just think about it, even the word stroke implies something suddenly like a bolt of lightning out of the blue the damage is done. We have a lot of treatments now clot-busting medicines, procedures that allow us to treat people with acute stroke. They have to get to us quickly enough for us to be able to help them so that’s why it’s so important to educate people about stroke warning signs and stroke symptoms and make sure that they seek help.”

As part of World Stroke Day, the American Heart and Stroke Association is encouraging people to take part in One CycleNation, an event to get people moving and raise money to support the AHA.