People who frequently lose their train of thought or often become sidetracked may be displaying earlier symptoms of cerebral small vessel disease, also known as a "silent stroke," a study warns. The study, published in the journal Neurobiology of Aging, found that adults with damage to the brain's white matter, caused by silent strokes, reported poor attentiveness and being distracted more frequently on day-to-day tasks.
Despite these complaints, about half of the people with identified white matter damage scored within the normal range on formal laboratory assessments of attention and executive function. The executive function is a person's ability to plan, stay organised and maintain focus on overall goals.
"Our results indicate that in many cases of people who were at a higher risk of silent stroke and had one, they saw a notable difference in their ability to stay focused, even before symptoms became detectable through a neuropsychological test," said Ayan Dey from the University of Toronto in Canada.
"If a person feels this may be the case, concerns should be brought to a doctor, especially if the person has a health condition or lifestyle that puts them at a higher risk of stroke or heart disease," Dey said.
Cerebral small vessel disease is one of the most common neurological disorders of ageing. This type of stroke and changes in the brain's blood flow (vascular changes) are connected to the development of vascular dementia and a higher risk of Alzheimer's disease and other dementias.
The strokes are "silent" since they do not cause lasting major changes seen with an overt stroke, such as affecting a person's ability to speak or paralysis. Despite a lack of obvious symptoms, cerebral small vessel disease causes damage to the brain's white matter (responsible for communication among regions), which can cause memory and cognitive issues over time.
Typically, this type of stroke is uncovered incidentally through MRI scans or once the brain damage has worsened, said Dey. "There are no effective treatments for Alzheimer's disease, but brain vascular changes can be prevented or reduced through smoking cessation, exercise, diet and stress management, as well as keeping one's blood pressure, diabetes and cholesterol under control," said Brian Levine from the University of Toronto.
"With the right diagnosis, these interventions and lifestyle changes give older adults who are at risk for cognitive decline some options for maintaining brain health," Levine said.
The study looked at results from 54 adults (between the ages of 55 to 80), who also possessed at least one risk factor for a stroke, such as high blood pressure, high cholesterol, diabetes, sleep apnea, a history of smoking, past mini strokes and advanced age above 75.
Research participants had their brains scanned by MRI and scientists analysed brain tissue damage, specifically in relation to white matter, to determine injuries caused by cerebral small vessel disease. They also took part in a number of neurocognitive tests and questionnaires that assessed their attention and executive function.