The harm of a ‘mini stroke’ may be greater than previously thought

TIAs, sometimes referred to as “mini strokes,” may cause more long-term damage than commonly thought.

A TIA, or transient ischemic attack, is a temporary blockage of blood supply to part of the brain, according to the National Institute of Neurological Disorders and Stroke. Similar to a stroke, it causes symptoms such as weakness or lack of feeling in a limb or face, typically only on one side of the body, as well as confusion and dizziness, difficulty speaking or understanding conversation, vision problems or trouble walking.

Unlike a stroke, which causes permanent brain damage, TIA symptoms quickly fade, sometimes in under an hour, leading some people to disregard them or not seek immediate help.

While having a TIA has been associated with a greater risk of suffering another TIA or a stroke, a study published Feb. 10, 2025, in JAMA Neurology compared the rate of loss of verbal and memory skills in 356 people who had a first-time TIA with 965 people who had a first stroke, as well as 14,882 asymptomatic people in a control group. The stroke patients had more cognitive decline (14 percent) compared with the TIA group (1 percent) shortly after their attacks, but the yearly rate of erosion of brain abilities was similar between the TIA group (5 percent) and the stroke group (4 percent). The study did not determine if TIAs alone were responsible for the rate of decline or whether other risk factors or pre-existing cognitive decline played a part.

Cognitive Decline

Alba Coraini, MD, who practices at Neurologists of Cape Cod in Hyannis, said she wasn’t surprised by the study’s results. She said she sees cognitive decline in both stroke and TIA patients.

The cause in TIA patients may be a combination of risk factors such as high blood pressure, high cholesterol levels, diabetes, and atrial fibrillation (AFib, a common type of heart arrythmia), she said.

Often, first-time TIA patients have gone untreated for one or more of these risk factor conditions, which aren’t discovered until the patient undergoes work-up after a TIA, Dr. Coraini said. These conditions can lead to a TIA by damaging blood vessels in the brain. Cholesterol can build up plaque on blood vessel walls, restricting blood flow, and diabetes and high blood pressure can cause blood vessels' walls to thicken, constricting the space for blood to pass. Atrial fibrillation can cause a clot to form in the heart, which can then be pumped to the brain and partially or fully block a blood vessel there, according to the American Heart Association.

“It’s important to treat these risk factors to prevent the recurrence of TIAs or stroke”, she said. “Once a patient has a TIA or stroke, it’s very important to follow up with a neurologist.”

Prevention and Treatment

Don’t ignore symptoms of a TIA or stroke. Instead, seek help immediately, Dr. Coraini said. According to the National Institute of Neurological Disorders and Stroke, there’s no way outside of the hospital to differentiate whether a person is suffering a TIA or a stroke, and there is a short window of time in which strokes need to be treated to prevent permanent damage to the brain, she said.

Most strokes are ischemic, caused by a blood clot, and patients must be given a clot-dissolving drug within three hours of the stroke for the treatment to be most effective. Some patients may get some help from this method as late as four and a half hours afterward, according to the National Heart, Lung and Blood Institute. Ischemic stroke patients may need surgery to remove a clot.

“Even if your symptoms go away, it’s very important that patients do seek medical attention,” Dr. Coraini said.

Patients may undergo an MRI (magnetic resonance imaging) scan or other imaging of their brain to determine if they had a TIA or stroke and the extent and location of damage. They may also have an ultrasound done of their heart and be fitted with a heart monitor. If diagnosed with a TIA, patients will need treatment to prevent recurrence.

“Patients with TIA are at risk of another TIA or stroke, which is highest in the weeks right after the event,” Dr. Coraini said.

Treatment could include low-dose aspirin in the short term, she said. Any untreated medical condition would be addressed, such as starting a blood thinner for people with a cardiac arrythmia. Recommended lifestyle changes to address contributing risk factors include:

• Eating a healthy diet.
• Exercising regularly
• Avoid smoking.
• Not consuming alcohol in excess.
• Staying hydrated. “If you’re dehydrated, you’re at risk of reduced blood flow to the brain,” she said.
• Controlling blood pressure and cholesterol levels.

TIAs and strokes are “insults to the brain,” Dr. Coraini said, and they can lead to worsening cognition and dementia. In addition to treating underlying conditions and following a healthy lifestyle, “socialization is very important,” she said. “Try to keep the mind active.”