THINK THE acronym FAST to identify the most common symptoms of a TIA (transient ischemic attack). Although the risk of having a stroke more than doubles each decade after age 55, nearly one-fourth of strokes occurs in those under 65.
Each letter of FAST (remember face, arm, speech and time) stands for a warning sign or course of action. F is for drooping face (check the smile); A for arm weakness (raise both arms and compare); and S for speech difficulty (repeat a simple sentence like “the sky is blue”).
The best outcome of such signs is the diagnosis of a TIA, sometimes called a mini-stroke or warning stroke. In the case of a TIA, blood clots that block arteries are naturally dislodged or dissolved, leaving no injury to the brain. But anyone with these signs, however brief or minor, should go directly to the ER.
T is for time, because the 911 call should be made immediately and include both the words “I think…stroke” and the time of the first symptoms. TIAs can last less than an hour and sometimes as little as one minute, though symptoms can endure for up to 24 hours.
Time is crucial because, if the incident is in fact a stroke—meaning that blood flow is not restored quickly enough to avoid injuring brain cells—the best treatment is the extremely time-sensitive TPA (tissue plasminogen activator) to dissolve clots.
TPA, known as a thrombolytic agent, must be given within three hours—in some eligible patients up to four and a half hours—to minimize damage. Before TPA can be given, intravenously, for most patients a non-contrast CT head scan and glucose test are required.
Other important sudden signs are weakness or numbness especially on one side of the body; trouble walking, dizziness, fainting or loss of balance; severe headache; and abnormal sense of taste or smell.
Problems with speech, called dysphasia, include difficulty recalling words, saying words or understanding words. They are often the only symptoms of a TIA and indicate that the blockage has occurred in the dominant brain hemisphere.
Visual disturbances, called transient monocular blindness or amaurosis fugax, cause the vision in one eye to become suddenly dim or obscured, and things can look gray or blurry. Exposure to bright light can make symptoms worse, and reading words on a white page can be impossible.
Anyone (no matter the age) with any of these signs should be evaluated for a possible stroke. Of the 10 or 15% of strokes occurring in people age 45 and younger, one in seven was misdiagnosed as vertigo, migraine, alcohol intoxication, inner ear disorder or other problems—and the patient was sent home without proper treatment, writes Jane Brody in the New York Times.
Of all strokes, 85% are traced to a blood clot and labeled “ischemic”— caused by an inadequate supply of the arterial blood responsible for transporting oxygen, vital to cellular survival, to organs like the heart and brain. Obstruction of arterial blood flow can also be created by diseases such as hypertension; atherosclerosis, narrowed arteries caused by the buildup of fatty deposits called plaque (carotid artery disease occurs when arteries in the neck are blocked by plaque); and diabetes.
Although TIAs cause no damage, they are most aptly called “warning” strokes because about one-third of people who experience a TIA have a more severe stroke within a year. DC-area residents can breathe more easily than some: the highest rates of death from stroke occur in the “Stroke Belt,” in the southeastern U.S. and Mississippi Valley.
When TIA or stroke is suspected, initial tests check for risk factors: high blood pressure—the most important one for stroke; high cholesterol levels; diabetes; and high levels of the amino acid homocysteine, which can increase odds of a blood clot.
Further assessments are made using ultrasound on the carotid arteries to show narrowing or clotting; MRI and CT scans as well as arteriography, with or without contrast, to look at the brain and to evaluate the arteries; and one kind of echocardiogram for clearer, more detailed images.
For both TIA and stroke, the most common prescription is anti-platelet drugs, most often aspirin or preparations containing aspirin. Anticoagulants like heparin can affect clotting-system proteins but require careful monitoring. (Confusingly, anti-platelet drugs like aspirin are often referred to as anticoagulants.) Surgery to clear fatty deposits or widen narrow arteries can help prevent future attacks.
But the best prevention, besides not smoking, is to keep blood pressure down. A recent study of almost 1,000 adults, average age 68, was stopped early because of such clear benefits of a target pressure of 120 mm systolic (the top number) or less.
In the brain portion of the study, called SPRINT-MIND, the group receiving this intensive approach also had a 19% lower rate of new cases of MCI (mild cognitive impairment) and a subgroup had significantly less increase in white brain matter lesions—an increase associated with normal aging and with a higher risk of stroke, dementia and higher mortality.
According to the American Heart Association, every rise of 20/10 mmHg above 115/75 mmHg doubles the risk of cardiovascular disease —and the recommendation is to treat pressure at and above 130/80 mmHg.
Every Tuesday in this space, well-being editor Mary Carpenter fills us in on the latest health news.