A strike against stroke

Every 40 seconds, someone in the United States suffers a stroke. That adds up to 795,000 strokes a year. And the number doesn’t count invisible “silent” strokes.

Every four minutes, someone dies of a stroke. Though death rates have dropped, strokes still kill more than 137,000 Americans a year. That makes stroke the fourth-leading cause of death.

Stroke 101

A typical stroke is essentially a heart attack in your brain.

Roughly nine out of 10 strokes are ischemic. That means they occur when arteries in or on the way to the brain get blocked by a blood clot. The trigger: a ruptured plaque in blood vessels in the brain or neck or near the heart —or a clot in the heart—that travels to the brain.

“The clot can block the blood vessel or it can break into little pieces that go all over the body, including the brain,” explains Norm Campbell, professor of medicine, community health sciences, and physiology and pharmacology at the University of Calgary in Canada.

If the clot cuts off the blood supply to the brain, oxygen-starved brain cells near the blocked vessel die. Two million brain cells die every minute during a stroke, causing brain damage, disability, or death.

Six months after having an ischemic stroke, a fifth of survivors aged 65 or older have trouble speaking, a third can’t walk without assistance, and a quarter are in a nursing home.¹

“Hemorrhagic strokes are even more tragic,” says Campbell, who chairs the Canadian Hypertension Advisory Committee.

Hemorrhagic strokes—which occur when a blood vessel in or around the brain bursts—account for 13 percent of strokes in the United States, but 30 percent of stroke deaths.

Call 9-1-1

One drug has revolutionized the treatment of ischemic strokes. In 1996, the Food and Drug Administration approved the use of tissue-plasminogen activator (tPA) to break up clots and restore the brain’s blood supply. The catch: you don’t have much time.

“The FDA’s approval is for three hours, but our national guidelines allow us to go out to four hours in selected patients,” says Larry Goldstein, director of the Stroke Center at Duke University Medical Center in North Carolina. “But what’s very, very clear is that the sooner you get treated, the more likely that the drug is going to be of benefit.”

That doesn’t mean you have three hours to arrive at the hospital.

“The current national goal is one hour from arrival to treatment, but that’s extraordinarily difficult to do in many settings,” says Goldstein, who chaired the American Heart Association’s 2011 Guidelines for the Primary Prevention of Stroke.²

“A variety of things slow things down.”

Among them: “A CT scan and blood tests have to be taken, other potential reasons for the symptoms have to be excluded, and the patient has to agree to take the drug.”

But the hospital isn’t usually the problem. “The single most important reason people aren’t treated with intravenous tPA is that they don’t get to the hospital soon enough,” says Goldstein.

It’s not just that people fail to recognize the symptoms. “Denial is very important,” notes Goldstein. “People don’t believe that a stroke is happening or they dismiss it and the people around them dismiss it.”

And time is brain, as they say.

“If you’re too late, there are no treatment options available,” says Campbell. “It’s a true emergency. You need to call an ambulance.”

Even if the warning signs disappear, call 9-1-1. You might be having a TIA, or transient ischemic attack.

“A TIA is one of the greatest predictors of having a true stroke”—that is, one that causes permanent damage, notes Campbell. “You may not need a clot-busting drug, but you need treatment,” often with drugs to lower blood pressure or prevent clots.

“You don’t want to have the stroke and then be treated. A TIA is a great opportunity to prevent a stroke. It shouldn’t be squandered by delay.”

Richard Dykema was eventually treated with tPA, “but it didn’t turn things around,” says Holly. “I’ve heard so many stories about people who go into the hospital and can’t move their limbs, can’t talk, and walk out of the hospital totally fine. The drug is amazing.”

TPA may not have helped because Richard had a carotid dissection, which can start with a small tear in the lining of the carotid artery in the neck. That allows blood to enter the space between the inner and outer layers of the artery wall, narrowing or completely blocking the blood vessel.

“I didn’t even know what a stroke was when he had it,” says Holly. “One day I had had problems seeing out of one eye, and it wasn’t serious. So I said, ‘Don’t worry about it.’ Silly me.”

The urgent need to treat stroke symptoms has led to campaigns to publicize a stroke’s warning signs (see “Signs of a Stroke”). But knowing the warning signs can’t help with strokes that have no symptoms.

Silent strokes

“In silent strokes, people can speak normally and have normal power and feeling in their limbs,” says Campbell. “They don’t get the warning signs of stroke so they don’t go to the hospital.” Nevertheless, silent strokes cause brain cells to die.

“What’s emerging is that silent strokes are probably precursors of dementia,” says Campbell. “People become cognitively impaired as the burden of silent strokes increases.”

Scientists used to distinguish Alzheimer’s disease from vascular dementia caused by clogged blood vessels, but no longer.³

“There’s a big overlap between vascular dementia and Alzheimer’s disease,” explains Goldstein. “Finding pure Alzheimer’s or pure vascular dementia is the rarity, not the rule. Most people have at least some components of both.”

And the number of Americans suffering from dementia is climbing. So is the cost.

“We’re an aging population,” says Campbell. “When you look at hospitalizations, physician visits, and drugs to treat strokes and heart attacks, the cost is essentially bankrupting the health care system.”

The answer isn’t just to get people to act when they see warning signs or to come up with better treatments for strokes.

“I view those as waiting-for-a-stroke programs,” says Campbell. “Society needs to be more proactive to prevent strokes from occurring in the first place. We know how.”

Prevention

“We know that people who follow a healthy lifestyle have a dramatically lower risk of stroke than people who don’t,” says Goldstein.

For example, in a study that tracked some 44,000 men and 71,000 women for 16 years, five aspects of lifestyle made a difference.⁴

“People who don’t smoke, who are not overweight, who don’t drink alcohol in excess, who exercise regularly, and who eat a healthy diet have about an 80 percent lower risk of a first stroke,” explains Goldstein. “And the risk decreases for each of those lifestyle habits.”

(In the study, a “healthy” diet meant higher intakes of vegetables, fruits, nuts, soy, grain fiber, chicken, and fish and lower intakes of red meat, saturated fat, and trans fat.)

And in studies on some 257,500 people, those who ate more than five servings of fruits and vegetables a day had about a 25 percent lower risk of stroke than those who ate less than three servings a day.⁵

Those studies weren’t trials so they can’t prove cause and effect. It’s possible that people who eat healthier diets also do other things that lower their risk.

But odds are that a healthy lifestyle means fewer risk factors for stroke (see “What’s Your Risk?” p. 5). Some risk factors— like age and family history—you can’t change. Of those you can, one stands out: “The single most important risk factor for a stroke is high blood pressure,” says Goldstein.

Keep blood pressure low

“An optimal blood pressure is less than 115 systolic over 75 diastolic,” says Campbell. “As long as a disease hasn’t caused blood pressure to go low, that’s healthy.”

(The target for people who are taking blood-pressure drugs is 140 over 90, notes Campbell. “I wouldn’t want those people to ask their docs to lower their pressure to 115 over 75,” he says.)

Why is lower better? “As blood pressure rises, all of the blood vessels in the body are damaged,” says Campbell. “And that causes strokes, heart attacks, heart failure, kidney failure, dementia, impotence, and difficulty with walking.”

Doctors diagnose patients with high blood pressure, or hypertension, when either the upper number reaches 140 or the lower number hits 90.

“Doctors and patients like having goal numbers, but it’s not like at 139 over 89 you have no risk and at 141 over 91 suddenly you have risk,” says Goldstein.

In fact, the risk starts to rise well before 140 over 90. “Around 60 to 70 percent of clinical strokes are caused by increased blood pressure,” explains Campbell. “Half of those strokes occur in people with high blood pressure and half strike those with increased-but-not-high blood pressure.” Increased-but-not-high blood pressure— or prehypertension—ranges from 120 to 139 systolic over 80 to 89 diastolic. “Normal” is less than 120 over less than 80.

“We use different names but the reality is that as blood pressure increases, the damage increases,” says Campbell.

Here’s how you can keep your pressure low, according to a report by the Institute of Medicine, the health arm of the National Academy of Sciences⁶:

• Lose excess weight. If you’re overweight, losing about 10 pounds could trim systolic blood pressure by an average of six points.
• Eat a DASH-like diet. A DASH diet is built around vegetables, fruit, low-fat dairy, and unsaturated fat instead of added sugars, refined starches, and saturated fat (see “What to Eat”). A DASH diet can lower systolic blood pressure by about six points. (That doesn’t count the drop in pressure from the cut in sodium that’s usually recommended as part of the DASH diet.)
• Scale back salt. Cutting sodium in half (that means trimming about 1,700 milligrams a day for the average American) could cut systolic blood pressure by around four points.
• Eat more potassium. Potassium-rich fruits and vegetables can lower systolic blood pressure by about three points. (That accounts for half of the six-point drop you can expect from the DASH diet.)
• Exercise. Regular aerobic exercise like brisk walking can lower systolic blood pressure by two to four points.
• Limit alcohol. No more than two drinks a day for men or one drink a day for women can cut systolic blood pressure by an average of three points.

It’s not hard to see the food industry’s role in raising our blood pressure.

“Sodium is added during food processing, by restaurants or in packaged foods,” notes Campbell. “Both have too little potassium due to lack of fruits and vegetables. And obesity is due to calorie density due to sugars and saturated and trans fats.

“Food companies are killing us, but we’re not supposed to demonize them.”

Don’t give up

Richard Dykema hasn’t fully recovered from his stroke. “We used to be very active,” says his wife, Holly. “He used to ride a motorcycle, scuba dive, and hang glide. Now he’s in a wheelchair most of the time. Walking is difficult.

“He was hit on many levels. He has absolutely no use of his arm. His leg was paralyzed, but it’s come back some. And he has a communication disorder and cognitive issues.”

But Holly still has hope.

“For many years, the theory was that what you see at six months is what you get for the rest of your life,” she says. “I’ve been going to support groups for six years, and I’ve seen many people continue to make improvements years after their stroke.

“You may not be climbing mountains again, but that doesn’t mean you’ll never be able to walk out your front door. You have to reinvent your life.”

For Holly, that meant starting the Stroke Association of Florida (SAF) to help other survivors and caregivers in Sarasota and Manatee counties.

At first, she explains, “I barely knew when my next shower was going to come, let alone who would care for Richard when I went back to work.”

The SAF offers information on support groups and a local resource guide.

“When Richard first came home, I needed a transfer board to get him in and out of the car,” says Holly. “A couple of months down the road, he no longer needed that.

“Then he needed a device to help him go fishing one-handed. How do you open a jar or operate a zipper with one hand? Your needs are going to change.”

The SAF’s second goal is to educate the local community.

“People need to know about the lifestyle changes that can prevent strokes,” says Holly. “And they need to know that they should call 9-1-1 immediately, because waiting to see if symptoms go away can mean the difference between complete recovery and disability.”

¹Circulation 125: e2, 2012.
²Stroke 42: 517, 2011.
³Stroke 42: 2672, 2011.
⁴Circulation 118: 947, 2008.
⁵Lancet 367: 320, 2006.
⁶ books.nap.edu/openbook.php?record_id=12819.