Deficits in brain's 'executive' skills common with TIA, minor stroke

February 24, 2010

Nearly four in 10 transient ischemic attack (TIA) and minor ischemic stroke patients may experience mental impairment, according to a study presented at the American Stroke Association's International Stroke Conference 2010.

Researchers evaluated 140 patients (average age 67) admitted to the Urgent TIA Clinic at the London Health Sciences Centre in London, Ontario. Within a week of symptom onset, the researchers used a short, easily administered battery of tests that can detect deficits in so-called "executive functions," including speed of mental processing, abstraction and reasoning ability. They found that these functions -- higher-level cognitive skills that control and coordinate other mental abilities and behaviors -- were impaired in almost 40 percent of the TIA and minor stroke patients.

Researchers have known that TIAs and minor strokes can subtly change mental abilities, a condition known as vascular cognitive impairment. But little has been known about how common impairment was in these patients.

"Transient ischemic attacks and minor strokes are not just a warning of future stroke. They are an indication that the process of brain injury may have begun," said Michael Harnadek, Ph.D., the study's lead author and a neuropsychologist with the London Health Sciences Centre.

Researchers also administered the most commonly used test for mental functioning, the Mini Mental Status Exam, which is designed to identify patients with Alzheimer's dementia. They found that test couldn't detect the cognitive problems in minor stroke and TIA patients. Harnadek said this indicates while cognitive impairment is common in patients who have experienced TIAs and minor strokes, it can be missed if doctors rely only on measures designed to test for Alzheimer's dementia.

"Using measures that specifically test executive functioning, screening for cognitive impairment can be done quickly and easily," he said.

Ischemic events -- caused by a blockage in a blood vessel in or leading to the brain -- account for about 85 percent of all strokes. About one-third of people who have a TIA, also known as a "warning stroke," have a stroke within a year, according to the American Stroke Association.

In a May 2009 statement, the American Heart Association/American Stroke Association re-defined TIA as a transient episode of neurological dysfunction caused by focal brain (an injury confined to one area of the brain), spinal cord or retinal ischemia without acute infarction. Infarction is tissue death, currently the main distinction between TIA and stroke, and can be determined by magnetic resonance imaging (MRI).

Symptoms of a TIA and stroke are the same and include sudden onset of any of the following:Among the patients in the study who experienced a TIA, symptoms went away within 24 hours, while for the minor stroke patients, physical or sensory symptoms persisted but didn't cause serious disability.

Sixty-one percent of the study subjects were women, but the researchers haven't yet determined whether rates of impairment varied between males and females. The study also didn't include enough patients to discern differences among racial or ethnic groups, Harnadek said.

The study should be replicated elsewhere to see whether rates of impairment are similar for the same type of patients, he said. Researchers should also try to learn whether patients' impairment interferes with their ability to understand and follow the treatment guidance their physician provides.

"Our research, and similar studies, underscores the need for the prevention of cerebrovascular disease, as well as early detection and treatment in those affected, to preserve cognitive health," Harnadek said.
-end-
Co-authors are: Richard Chan, M.D.; Cheryl Mayer, R.N., M.Sc.N.; and Vladimir Hachinski, M.D., D.Sc. Author disclosures are on the abstract.

Funding for the study was provided through the Canadian Stroke Network.

Click here to download audio clips offering perspective on this research from American Stroke Association spokesperson, Bruce Ovbiagele, M.D., Assistant Professor of Neurology, UCLA School of Medicine, Los Angeles, Calif.

Statements and conclusions of study authors that are presented at American Heart Association/American Stroke Association scientific meetings are solely those of the study authors and do not necessarily reflect association policy or position. The association makes no representation or warranty as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing science content. Revenues from pharmaceutical and device corporations are available at www.americanheart.org/corporatefunding.

NR10-1009 (ISC 2010/Harnadek)

American Heart Association

Related Stroke Articles from Brightsurf:

Stroke alarm clock may streamline and accelerate time-sensitive acute stroke care
An interactive, digital alarm clock may speed emergency stroke care, starting at hospital arrival and through each step of the time-sensitive treatment process.

Stroke patients with COVID-19 have increased inflammation, stroke severity and death
Stroke patients who also have COVID-19 showed increased systemic inflammation, a more serious stroke severity and a much higher rate of death, compared to stroke patients who did not have COVID-19, according a retrospective, observational, cross-sectional study of 60 ischemic stroke patients admitted to UAB Hospital between late March and early May 2020.

'Time is vision' after a stroke
University of Rochester researchers studied stroke patients who experienced vision loss and found that the patients retained some visual abilities immediately after the stroke but these abilities diminished gradually and eventually disappeared permanently after approximately six months.

More stroke awareness, better eating habits may help reduce stroke risk for young adult African-Americans
Young African-Americans are experiencing higher rates of stroke because of health conditions such as high blood pressure, diabetes and obesity, yet their perception of their stroke risk is low.

How to help patients recover after a stroke
The existing approach to brain stimulation for rehabilitation after a stroke does not take into account the diversity of lesions and the individual characteristics of patients' brains.

Kids with headache after stroke might be at risk for another stroke
A new study has found a high incidence of headaches in pediatric stroke survivors and identified a possible association between post-stroke headache and stroke recurrence.

High stroke impact in low- and middle-income countries examined at 11th World Stroke Congress
Less wealthy countries struggle to meet greater need with far fewer resources.

Marijuana use might lead to higher risk of stroke, World Stroke Congress to be told
A five-year study of hospital statistics from the United States shows that the incidence of stroke has risen steadily among marijuana users even though the overall rate of stroke remained constant over the same period.

We need to talk about sexuality after stroke
Stroke survivors and their partners are not adequately supported to deal with changes to their relationships, self-identity, gender roles and intimacy following stroke, according to new research from the University of Sydney.

Standardized stroke protocol can ensure ELVO stroke patients are treated within 60 minutes
A new study shows that developing a standardized stroke protocol of having neurointerventional teams meet suspected emergent large vessel occlusion (ELVO) stroke patients upon their arrival at the hospital achieves a median door-to-recanalization time of less than 60 minutes.

Read More: Stroke News and Stroke Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.