What To Know About Mini-Strokes

A transient ischemic attack (TIA), colloquially known as a “mini-stroke,” shares many similarities with a stroke — but there’s a big difference between the two. Symptoms of a TIA go away within minutes, leading people to believe that mini-strokes do not cause long-term damage.

Now, a new study in the journal JAMA Neurology concludes that a mini-stroke can actually have a major impact, with measurable long-term cognitive decline.

The memory loss after a TIA, the study reports, can be as significant as after a regular stroke.

These findings are likely to lead to more aggressive treatment and follow-up after a TIA event.

“The reasons for memory loss after TIA are not clear,” says Tatjana Rundek, M.D., Ph.D., a neurologist with the University of Miami Health System. “However, this finding indicates that there is underlying vascular pathology, either by direct or secondary injury as indicated by the authors.”

Threading out the potential damage wrought by a TIA is further complicated by the demographics of the patient population. TIAs are more common in older adults, particularly those with risk factors like high blood pressure, diabetes, heart disease, or smoking.  In fact, stroke rates double every 10 years after age 55.

“The aging process combined with possible underlying neurodegenerative factors may contribute to memory and other cognitive impairments after TIA, but these mechanisms still need to be explained,” says Dr. Rundek, who is also the director of the Clinical Translational Research Division in Neurology at the Miller School of Medicine.

Learning more about the mechanism of post-TIA cognitive decline is therefore crucial as the population ages.

About 240,000 people experience a TIA every year, according to the American Stroke Association.

However, since the TIA incidence increases with age (just like heart disease and stroke), an aging population may mean more incidents in the future. Some research suggests that hospitalization rates for TIAs have already been increasing, especially in older adults.

Moreover, neurologists believe the current incidence rate is likely much higher. “Many TIAs go undetected because of lack of recognition of TIA symptoms by the public,” says Dr. Rundek.

The symptoms are often mistaken for other conditions, meaning some people may not seek medical attention.

 In the JAMA Neurology study, researchers looked at data from more than 16,000 people who were at least 45 years old and had never experienced a TIA or stroke. About two-thirds were white, and one-third were Black. They followed the subjects for an average of 14 years and compared their cognitive changes using brain imaging and cognitive function assessments. During that time, the subjects were then divided into three groups: those who hadn’t suffered a TIA or stroke, those who had a first-time TIA, and those who had a first-time stroke.

Not surprisingly, those who had suffered a stroke showed significant cognitive decline immediately after the event. They also worsened over time. The decline for those with a TIA, on the other hand, did not happen right away but gradually, ending up similarly to those who had a stroke. Compared to the control group with no neurological incident, the TIA group showed a “significantly faster” decline. That decline was in delayed memory recall rather than verbal fluency.

Dr. Rundek urges anyone who experiences certain symptoms to seek immediate emergency help.

Remembering the telltale symptoms can be easy with the acronym

BE FAST:

• Balance (loss of balance or coordination)
• Eyes (changes in vision)
• Face (dropping one side of face)
• Arms weakness or numbness in one arm or leg)
• Speech (slurred or confused speech, trouble understanding words)
• Time to call 911  

Also, remember that pain shouldn’t be the guide for seeking emergency care. A person doesn’t experience pain during a TIA.

 “A TIA should be taken seriously as an emergency that requires immediate medical evaluation and treatment to prevent a major stroke,” she says. 

Even if tests show no damage, it’s better to be safe than sorry.

Immediate action is recommended since a TIA can prove to be devastating in the long term.

A TIA is caused by a temporary blockage of blood flow in the brain just like in an ischemic stroke. Unlike a stroke, this blockage clears up on its own.

In other words, the blood supply is restored quickly. This, however, doesn’t mean a patient is in the clear.

TIAs are often a harbinger of a bigger problem.

“Both TIA and stroke are ‘risky’,” Dr. Rundek says. “While a stroke has more immediate risks and consequences, a TIA is a predictor of high stroke risk. After a TIA, the risk of having a major stroke is highest in the first few days to weeks, whereas stroke poses a high risk of recurrent stroke and long-term disability. Both pose a high risk of cognitive decline.”

Up to 17% of people who have had a TIA will have a stroke within 90 days, with almost half of those occurring within two days. When given the appropriate scan, two in five patients who believed they had had had a TIA, will learn that they actually had a stroke instead of a TIA.

“The most effective and proactive public health message would be to educate our communities to recognize the signs and symptoms of stroke and call 911,” says Dr. Rundek, adding that timely, aggressive treatments “are best to prevent cognitive outcomes post TIA or stroke.”

To determine the extent of the blood flow stoppage, an urgent diagnostic workup should include brain imaging and vessel imaging (MRI, CT, ultrasound) and assessment of heart-related embolic sources (such as cardiac echo and prolonged monitoring). Immediate management entails antiplatelet or anticoagulant therapy, statins, blood pressure, and diabetes control, and cardiac or carotid interventions as needed.

As for long-term treatment, Dr. Rundek recommends lifestyle changes and close follow-up visits.

Because risk factors for these mini-strokes include diabetes, heart disease, high blood pressure, atrial fibrillation and smoking, physicians advise TIA patients to focus on risk reduction by changing their food and exercise habits. Dr Rundek lists them as:

• Quitting smoking immediately
• Limiting alcohol consumption
• Exercising 150 minutes/week with moderate-intensity exercise
• Practicing weight management (recommended BMI should be less than 25)
• Eating a healthy diet high in omega-3s, fruits, and vegetables
• Reducing salt, sugar, and processed foods
• Assessing and treating obstructive sleep apnea, if needed

“Lifestyle changes are critical for long-term prevention of stroke as well as for cognitive decline,” Dr. Rundek concludes.

Written by Ana Veciana-Suárez, a regular contributor to the University of Miami Health System. She is an acclaimed author and journalist who has worked for The Miami Herald, The Miami News, and The Palm Beach Post.

Tags: Cognitive decline prevention, Dr. Tatjana Rundek, Long-term effects of mini-strokes, Stroke risk factors, Vascular cognitive impairment