A recent study found that about 10 percent of the apparently healthy middle-aged participants with no symptoms of stroke were injured from "silent strokes," researchers report in Stroke: Journal of the American Heart Association.
Silent cerebral infarction (SCI), or "silent stroke," is a brain injury likely caused by a blood clot interrupting blood flow in the brain. It's a risk factor for future strokes and a sign of progressive brain damage that may result in long-term dementia.
"The findings reinforce the need for early detection and treatment of cardiovascular risk factors in midlife," said Sudha Seshadri, M.D., co-author of the study and associate professor of neurology at Boston University School of Medicine. "This is especially true since SCIs have been associated with an increased risk of incident stroke and cognitive impairment."
Researchers evaluated magnetic resonance imaging (MRI) from about 2,000 people, average age 62, who are part of the Framingham Offspring Study (children of participants in the original Framingham Heart Study). The offspring have undergone clinical examinations every four to eight years.
Among patients who displayed no symptoms of stroke, 10.7 percent had SCIs on routine brain MRI, researchers said. Previous estimates of SCIs ranged from 5.8 percent to 17.7 percent depending on age, ethnicity and other issues. Of those in the study with SCIs, 84 percent had a single lesion.
The study is the first to correlate the total score of the Framingham Stroke Risk Profile to prevalence of SCI. The risk profile estimates the 10-year probability of having a stroke. The factors in the profile are age, systolic blood pressure, antihypertensive therapy, diabetes mellitus, cigarette smoking, cardiovascular disease, left ventricular hypertrophy and atrial fibrillation (AF).
All the components of the Framingham Stroke Risk Profile were positively associated with an increased prevalence of SCI. For the first time, researchers found a significant correlation between AF and silent cerebral infarction. AF is the most common form of heart arrhythmia, or irregular heartbeat in people older than 65.
"In our data, AF increased the risk of prevalent SCI more than two-fold," Seshadri said. Hypertension and systolic blood pressure were also associated with an increased prevalence of SCI.
Risk factors for stroke are also risk factors for AF. Hypertension and other factors that make it more likely individuals will experience AF also predispose those people to clinical stroke and probably to SCI. AF, therefore, may be a simultaneous outcome rather than a cause of SCI, researchers said.
The observational data could not indicate if screening for and appropriately treating AF would reduce the population burden of silent stroke, researchers said.
The study also found that high systolic blood pressure, hypertension and elevated levels of blood homocysteine, a sulfur-containing amino acid found in the blood, were other risk factors commonly associated with stroke that also raised participants' chances of having SCI. Hypertension consistently has been implicated as a risk factor of SCI. Neither age nor gender significantly changed the effect of any of the risk factors on SCI.
Researchers' ability to generalize findings for other ethnic groups is limited because participants in the Framingham study are mostly of European descent.
"The significant relationship between hypertension, elevated serum homocysteine, carotid artery disease and prevalent SCI underscores the importance of current guidelines for the early diagnosis and prevention of hypertension and atherosclerosis and their risk factors," Seshadri said.
Bridgette McNeill | EurekAlert!
3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg
Better equipped in the fight against lung cancer
16.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy