Dementia + Stroke a Potentially Fatal Combination
New research indicates dementia associated with a stroke can dramatically increase fatality risk
FRIDAY, Aug. 2 (HealthDay) -- As if having a stroke weren't bad enough: A mental disability known as dementia can be a strong predictor of death if it accompanies a stroke, researchers have found.
People with symptoms of dementia before or after a stroke have a much greater risk of dying within the next two years, reports a study in the August issue of Stroke: Journal of the American Heart Association.
In fact, dementia turned out to be one of the most important determinants of death in people who had had strokes.
Individuals who developed dementia after their stroke had a more than eight-fold increase in their risk of dying within two years. Those who had symptoms of dementia before the stroke had a risk of death twice as high as those with no dementia before or after. When the dementia was related to the stroke, the risk for death increased more than six times. This was true even after adjusting for other risk factors such as age, gender and heart disease.
The authors of the study speculate that this may be because stroke survivors with no dementia receive better care than those who do suffer from dementia. The study found that patients with dementia were less likely to receive oral anticoagulants, for example.
People with dementia have declining mental abilities, including memory loss, some motor skill degradation, confusion and often, the inability to find the right words to express a thought or idea.
Although the idea that individuals with stroke and dementia fare worse than their non-demented counterparts is not new, there may be some implications for prevention and care strategies.
"It is true, when a person has dementia, there is unfortunately a trend towards easing up on the care that they get," says Dr. Keith A. Siller, assistant professor of neurology at New York University School of Medicine in New York City.
"One thing you should take away from the study is that you should be just as concerned at modifying risking factors -- treating blood pressure, lowering cholesterol, giving anticoagulants and antiplatelets -- to those who have dementia," he adds.
It's a message the authors are also highlighting.
"We can say that cognitive impairment has prognostic implications in stroke patients," says Dr. Raquel Barba, lead author of the study and a clinical investigator in the department of medicine at Fundacion Hospital Alcoron in Madrid, Spain.
"Both pre- and post-stroke dementia determine a significant reduction in survival and are among the most important risk factors of mortality in these patients," she adds. "On the other hand, we must try to control other risk factors even in demented patients, because this can improve their prognosis."
Vascular dementia is caused by a narrowing of the blood vessels in the brain. Stroke is the most common acute neurological illness in the country, the leading cause of disability for adults and the third cause of mortality in developed countries. Post-stroke dementia can be found in some 20 to 30 percent of stroke patients.
Barba and her colleagues analyzed information on 324 patients who were admitted to a hospital in Madrid for stroke treatment in 1994 and 1995. Information from a questionnaire on cognitive decline (filled out by a patient's relative or caregiver) as well as a medical history and neurological evaluation identified pre-stroke dementia in 49 patients or about 15 percent of the patients.
Evaluations conducted three months later identified 75 people with post-stroke dementia, including 50 cases in which the dementia was related to the stroke.
After two years, only 58.3 percent of patients with stroke-related dementia had survived compared with 95.4 percent of patients without it.
"I think this reinforces the connection between dementia and stroke," Siller says. "What happens with dementia after stroke is a big topic in my field. Patients get through the stroke, but they may now be cognitively very poor. This is often more disabling than paralysis. This is a big health concern."
Ironically, the most severely disabled stroke patients may actually get the best care because they're often in a hospital or other facility and are totally supervised.
"It's the people in between who you may not even know are demented," Siller says. They may miss appointments, miss taking their pills, or take too many pills at one time.
"Some of these people may not get best medical care because the thinking process of the doctor changes when they don't know if the patient is reliable," Siller says. "It's wrong and unethical to withhold care even in an unconscious way."
What To Do
For more information on dementia, visit the American Geriatrics Society.