Transient ischaemic attacks (TIA) can eventually lead to cognitive declines as steep as those after a full-on stroke, suggests recent research, which found that over five years, study participants’ performance on cognitive tests after a TIA drops as steeply as it does among victims of a full-on stroke.
Medical experts are urging people to take a TIA, or mini-stroke, more seriously, saying a scarier name, like “minor ischaemic stroke” would more likely prompt an emergency call and initiate faster treatment, reports The New York Times.
Indiana’s Kristin Kramer woke up early one morning 10 years ago because one of her dogs needed to go out. Then, a couple of odd things happened.
When she tried to call her other dog, “I couldn’t speak”, she said. And then she noticed her right hand wasn’t working.”
But she went back to bed, “which was totally stupid”, said Kramer, now 54. “It didn’t register that something major was happening, especially because, reawakening an hour later, I was perfectly fine.”
So she ignored it and went to work.
Increase in cases
It’s a common response to the neurological symptoms that signal a TIA, experienced by at least 240 000 Americans each year, with the incidence increasing sharply with age.
Because the symptoms disappear quickly, usually within minutes, people don’t seek immediate treatment, putting them at high risk for a bigger stroke.
Kramer felt some arm tingling over the next couple of days and saw her doctor, who found nothing alarming on a CT scan. But then she started “jumbling” her words and finally had a relative drive her to an emergency room.
By then, she could not sign her name. After an MRI, she recalled, the doctor told her she’d had a small stroke.
Did those early-morning aberrations constitute a TIA? Might a 911 call and an earlier start on anti-clotting drugs have prevented her stroke? “We don’t know,” she said. She’s doing well now, but if she was faced with such symptoms again, “I would seek medical attention”.
Now, a large epidemiological study by researchers at the University of Alabama at Birmingham, published in JAMA Neurology, points to another reason to take TIAs seriously: over five years, study participants’ performance on cognitive tests after a TIA drops as steeply as it does among victims of a full-on stroke.
“If you have one stroke or one TIA, with no other event over time and no other change in your medical status, the rate of cognitive decline is the same,” said Dr Victor Del Bene, a neuropsychologist and lead author of the study.
An accompanying editorial by Dr Eric Smith, a neurologist at the University of Calgary, was pointedly headlined Transient Ischaemic Attack – Not So Transient After All!
The study showed that even if the symptoms resolve, typically within 15 minutes to an hour, TIAs set people on a different cognitive slope later in life, Smith said, “a long-lasting change in their cognitive ability, possibly leading to dementia”.
The study, analysing findings from data on more than 30 000 participants, followed three groups of adults over 45 with no history of stroke or TIA. “It’s been a hard group to study because you lack the base-line data of how they were functioning before the TIA, or stroke,” Del Bene said.
With this longitudinal study, however, researchers could separate those who went on to have a TIA from a group that went on to suffer a stroke and also from an asymptomatic control group. The team adjusted their findings for a host of demographic variables and health conditions.
“Immediately after a TIA, we don’t see an abrupt change in cognition, as measured by cognitive tests administered every other year,” Del Bene said. The stroke group showed a steep decline, but the TIA and control group participants were more or less neck and neck.
Five years later, the picture was different. People who had experienced TIAs were cognitively better off than those who had suffered strokes. But both groups were experiencing cognitive decline, and at equally steep rates.
After accounting for various possible causes, the researchers concluded that the cognitive drop reflected not demographic factors, chronic illnesses or normal ageing, but the TIA itself.
“It’s not dementia,” Del Bene said of the decline after a TIA. “It may not even be mild cognitive impairment. But it’s an altered trajectory.”
Combination
Of course, most older adults do have other illnesses and risk factors, like heart disease, diabetes or smoking. “These things together work synergistically to increase the risk for cognitive decline and dementia over time,” he said.
The findings reinforce long-standing concerns that people experiencing TIAs don’t respond quickly enough. “These events are serious, acute and dangerous,” said Dr Claiborne Johnston, a neurologist and chief medical officer of Harbor Health in Austin.
After a TIA neurologists put the risk of a subsequent stroke within 90 days at 5% to 20%, with half that risk occurring in the first 48 hours.
“Feeling back to normal doesn’t mean you can ignore this, or delay and discuss it with your primary care doctor at your next visit,” Johnston said. The symptoms should prompt a 911 call and an emergency room evaluation.”
Recognising a TIA
Dr Tracy Madsen, an epidemiologist and emergency medicine specialist at the University of Vermont, promotes the BE FAST acronym: balance loss, eyesight changes, facial drooping, arm weakness, speech problems. The T is for time, as in don’t waste any.
“We know a lot more about how to prevent a stroke, as long as people get to a hospital,” said Madsen, vice-chair of an American Heart Association committee that, in 2023,revised recommendations for TIAs.
The statement called for more comprehensive and aggressive testing and treatment, including imaging, risk assessment, anti-clotting and other drugs, and counselling about lifestyle changes that reduce stroke risk.
Unlike other urgent conditions, a TIA may not look dramatic or even be visible; patients themselves have to figure out how to respond.
Perhaps “transient ischeemic attack” is too reassuring a label, Johnston and a co-author argued in a 2022 editorial in JAMA. They suggested that giving a TIA a scarier name, like “minor ischaemic stroke”, would more likely prompt a 911 call.
The experts interviewed for this article all endorsed the idea of a name that includes the word “stroke”.
Changing medical practice is “frustratingly slow”, Johnston acknowledged, urging adherance to BE FAST.
Study details
Cognitive decline after first-time transient ischaemic attack
Victor A. Del Bene, George Howard, Toby Gropen, et al.
Published in JAMA Neurology on 10 February 2025
Abstract
Importance
Prior research suggests reduced cognitive function after transient ischaemic attack (TIA). Whether this is directly related to the TIA, a function of pre-existing risk factors, or prior cognitive decline remains unclear.
Objective
To study if a single, diffusion-weighted image–negative, adjudicated TIA is associated with longitudinal declines in cognition, independent of pre-existing risk factors.
Design, Setting, and Participants
This was a secondary data analysis from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a population-based cohort following up 30 239 black and white participants for incident cerebrovascular events. The setting consisted of telephone cognitive assessments. Participants were individuals with first-time TIA, first-time stroke, and asymptomatic community control groups with neuroimaging used for adjudication.
Exposures
First-time TIA and stroke.
Main Outcomes and Measures
Verbal fluency and memory measures administered biannually. Primary outcome was a composite standardised z score, with secondary outcomes individual test performances. Adjusted segmented regression models characterised pre-event and postevent cognition and annual cognitive change.
Results
Included in the study were 356 individuals with first-time TIA (mean [SD] age, 66.6 [8.7]; 188 female [53%]) and 965 individuals with first-time stroke (mean [SD] age, 66.8 [8.2]; 494 male [51%]). A total of 14 882 individuals (mean [SD] age, 63.2 [8.6] years; 8439 female [57%]) were included in the asymptomatic control group. Overall cognitive composite before index event was lower in the stroke (−0.25; 95% CI, −0.32 to −0.17) than TIA (−0.05; 95% CI: −0.17 to 0.07; P = .005) and asymptomatic (0; 95% CI, −0.03 to 0.03; P < .001) groups. After the index event, the cognitive composite of the group with stroke significantly declined (−0.14; 95% CI, −0.21 to −0.07) compared with that of the group with TIA (0.01; 95% CI, −0.10 to 0.12; P = .02) and controls (−0.03; 95% CI, −0.05 to −0.01; P = .003). The annual decline after the index event was faster (P = .001) in the group with TIA (−0.05; 95% CI, −0.06 to −0.03) than that for asymptomatic controls (−0.02; 95% CI, −0.02 to −0.02) but not different from the group with stroke (−0.04; 95% CI, −0.05 to −0.03; P = .43).
Conclusions and Relevance
Results of this cohort study suggest that despite the quick resolution of stroke symptoms in TIA, there was apparently sufficient impact to be associated with long-term cognitive decline. Whether the underlying mechanisms are by direct or secondary injury and/or interaction with concomitant neurodegenerative factors remains to be elucidated.
JAMA Neurology article – Cognitive decline after first-time transient ischaemic attack (Open access)
The New York Times article – A Mini-stroke Can Have Major Consequences (Restricted access)
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