Are you at risk for silent strokes?
Silent strokes may be particularly common in older people after they undergo elective surgery, and these strokes double their risk of cognitive decline in the year after the surgery according to a study in the August 2019 issue of the medical journal The Lancet.
In this study, one in 14 people 65 or older who had elective, non-cardiac surgery had a silent stroke as shown on MRI. Participants were followed for one year after their surgery to assess their thinking and memory skills. Those individuals who had a silent stroke after surgery were more likely to experience cognitive decline, major stroke, or another serious event during that time, compared with their counterparts who did not show evidence of a silent stroke on MRI.
What’s the difference between a silent stroke and a TIA?
Silent strokes are not the same as mini-strokes or so-called transient ischemic attacks (TIA), Dr. Bhatt adds. A TIA is a stroke that doesn’t cause lasting disability, because the symptoms are fleeting—but there are symptoms, he says. “Symptoms such as weak arm or leg are gone in 24 hours,” he explains.
A TIA is considered a medical emergency and suggests that a major stroke is imminent. “These are a warning sign that must be heeded,” says Dr. Bhatt. The risks for silent strokes, major strokes, and TIAs are the same, he says, and prevention is the best way to get ahead of any long-term consequences.
“Silent strokes become important if a person has stroke risk factors such as atrial fibrillation (irregular heartbeat), high blood pressure, high blood sugar, or high cholesterol, or family history of stroke and heart attack,” adds Dr. Arora.
Atrial fibrillation (also called AFib or AF) is the most common type of irregular heartbeat and, when untreated, is associated with a fivefold increased risk for stroke, according to the American Stroke Association. “Blood thinners can help people with AFib prevent stroke,” Dr. Bhatt says.”If you are not on blood thinners and have AF, you tend to have more silent strokes from little blood clots forming and killing off small parts of the brain.”
In a 2008 study in the journal Stroke, about 10% of middle-aged people without any stroke symptoms had signs of a silent stroke on MRI, and the risk of having one was more than double in those who had atrial fibrillation.
The symptoms of atrial fibrillation include a fluttering sensation of the heart and a heartbeat that is too fast or uneven, chest pain, dizziness, shortness of breath, and feeling light headed or fatigued. (Although the symptoms may not be obvious or could be mistaken for other problems.) Afib is more common in people over 60 as well as those with sleep apnea, hyperthyroidism, diabetes, high blood pressure, asthma, or heart disease, or who are binge drinking.