Stroke Archive

Research we're watching

Good news on the cancer front: The cancer death rate dropped 35% between 1991 and 2014 among children and 25% in adults, according to the annual American Association for Cancer Research Cancer Progress Report. And more treatments for the disease are on the horizon. The FDA has recently approved nine new cancer treatments and signed off on expanding the uses of eight existing therapies to treat different types of cancer. Among the new treatments are innovative immunotherapeutics, which help some people with cancer live longer with a better quality of life; an imaging agent that will let surgeons more precisely remove brain tumors; and molecularly targeted agents, which take aim at specific molecules that help cancers grow and spread to other areas of the body. It is hoped that these new treatments will further reduce cancer deaths. To read the full report, go to cancerprogressreport.org.

Closing a gap inside the heart may help prevent a rare type of stroke from recurring.

Image: Adapted from © rabbitteam/Thinkstock

Most strokes occur when a clot blocks blood flow to part of the brain. Often, doctors can tell what caused the clot to form. But about a quarter of the time — especially in people younger than 60 — there is no obvious reason. These types of strokes are known as cryptogenic (meaning "of hidden origin").

One possible cause underlying a cryptogenic stroke is an opening in the wall that separates the heart's right and left upper chambers (atria). Known as a patent foramen ovale, or PFO, this flaplike opening is quite common. About one-quarter of all adults have a PFO (see "What is a patent foramen ovale?").

It may help prevent a heart attack or stroke, but it comes with the risk of bleeding.

 Image: © Garsya/Thinkstock

Maybe you've heard about people who take a low-dose aspirin each day to ward off heart problems. Since aspirin is a medicine you've probably used now and then without a problem, and since it is available without a prescription, you might consider trying a daily low-dose aspirin yourself. Don't do it. Unlike deciding to take a multivitamin, taking a daily aspirin isn't something you should decide to do on your own.

Aspirin therapy is typically prescribed to people who have atherosclerosis of the arteries of the heart or brain, or risk factors for such disease. Just who should take a daily aspirin, how much aspirin, and what type of aspirin are hotly debated issues, with clinical trials under way in search of answers. "Until those results are in, you should talk to your doctor before starting aspirin," says Dr. Deepak Bhatt, a cardiologist and the editor in chief of the Harvard Heart Letter.

As men live longer, more face the challenge of difficult-to-control high blood pressure.

 Image: © KatarzynaBialasiewicz/Thinkstock

High blood pressure, or hypertension, remains a common health issue for a majority of older men.

In fact, approximately 54% to 67% of men ages 65 and older suffer from the condition, which occurs when your systolic pressure (the top number on a blood pressure reading) is 140 mm Hg or higher, and your diastolic pressure (the bottom number) is 90 mm Hg or higher, according to the American Heart Association.

In the journals

A common laser treatment may help people with a specific type of eye floater, according to a small study published online July 20, 2017, by JAMA Ophthalmology. Floaters are spots in your vision like black or gray specks, strings, flying bugs, or cobwebs. They become more prevalent with age and occur when the jelly-like substance inside the eyes becomes more liquid, shrinks, and separates from the back wall of the eye.

There are three treatments for floaters: observation, where a floater is monitored for changes (for instance, if it moves away from your central vision or the brain adapts and ignores it); vitrectomy surgery to remove the floater; and YAG vitreolysis, which vaporizes the floater with a laser.

As a group, men have nudged down their stroke numbers over the past decade. Why haven't women seen the same improvement?

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Men are less likely to have strokes than they were 10 years ago, but the risk for women has stayed about the same, according to a study of stroke data from Ohio and Kentucky, published online on August 21 by Neurology.

The question is, why?

"This study raises important concerns about the lack of decline in stroke rates in women," says Dr. Kathryn M. Rexrode, associate professor of medicine and chief of the Division of Women's Health at Harvard Medical School. Study authors suggested it's likely that better treatments for high blood pressure, high cholesterol, and diabetes, and a reduction in the number of people smoking helped to reduce the risk for men for having the most common type of stroke — ischemic stroke, which is typically caused by a clot that blocks blood flow to the brain. But women, who in theory should benefit from the same interventions, didn't see any improvement in their stroke rates over the study period.

Ask the doctors

Q. The July 2017 issue of Harvard Women's Health Watch spoke about the potential problems related to low blood pressure when taking blood pressure medication. My readings meet the definition of low blood pressure outlined in the article, but I don't take any medication. Should I be concerned, and if so, what should I do to raise my blood pressure?

A. In general, blood pressure is deemed too low only if it causes symptoms. A normal blood pressure is defined as a reading below 120/80 millimeters of mercury (mm Hg), and some experts consider your blood pressure low only if it dips below 90/60 mm Hg. However, a low reading can be normal for some people. Your doctor probably won't be too concerned about it unless it occurs suddenly; you have an underlying health condition that could cause low blood pressure, such as heart failure; or you are experiencing symptoms such as dizziness, lightheadedness, fainting, fatigue, or nausea. Some medications, such as diuretics (water pills), some antidepressants, and beta blockers, among others, can also cause low blood pressure. But since you aren't taking any medication, this is not an issue. If you are having symptoms related to your low blood pressure, this is something you definitely want to mention to your doctor. But if you've always had low blood pressure and you're not experiencing any problems, it's likely that this is normal for your body.

Research we're watching

A research letter published in the July 3 issue of the Journal of the American College of Cardiology says that shingles, a painful rash caused by the varicella-zoster virus (the same virus that causes chickenpox) may be linked to an increased risk of stroke and heart attack.

South Korean researchers used a national medical database to identify diagnoses of shingles, stroke, and heart attack and followed them from 2003 to 2013. They compared 23,213 individuals who had developed shingles during this period and compared their subsequent rates of heart attack and stroke to approximately 23,213 shingles-free individuals. They found that people who had shingles had a 35% higher risk of heart attack and a 59% higher risk of stroke.

Debris in your vision is a nuisance, but you may have to live with it.

 
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Strings, blobs, and cobwebs: they all describe types of specks that may appear to float across your field of vision. These "floaters" are usually just a nuisance. "In many cases, floaters become less noticeable or more tolerable over time, and can even disappear entirely," says Dr. Jeffrey Heier, an ophthalmologist and Harvard Medical School instructor.

But for some people, floaters are distracting to the point of interfering with vision.