A new study from the University of Michigan shows that having a stroke ages a person’s memory and brain function by almost eight years. Stroke, a publication of the American Heart Association, will publish the results in its July issue. The study team comprised members of the University of Michigan Medical School and School of Public Health and the VA Center for Clinical Management Research. The National Institutes of Health funded the study.
We talked with Deborah A. Levine, M.D., MPH, lead author of the study and a University of Michigan Medical School assistant professor, to learn more about the study and her thoughts on stroke prevention.
What was the effect of stroke on brain function?
We found that having a stroke meant that our participants’ score on a 27-item test of memory and thinking speed dropped as much as it would have if they had aged 7.9 years.
By measuring participants’ changes in cognitive test scores over time—from 1998 to 2012—we could see that both blacks and whites did significantly worse on the test after their stroke.
Why did your team undertake the study?
For years, researchers have known that blacks have a greater incidence of dementia. We were trying to find out if that is because of racial differences in acute stroke, the impact of stroke on cognitive health or other factors. We study differences in risk of stroke and cognitive decline between blacks and whites to better understand the reasons for these differences and also to better understand what causes these diseases.
How did you analyze the data?
We analyzed data from more than 4,900 black and white seniors over the age of 65.
We merged two sources of information for our analysis: detailed surveys and tests of memory and thinking speed over multiple years from participants in the Health and Retirement Study, a large, national study of older Americans, and Medicare data from the same individuals. We then zeroed in on the participants who had no recent history of stroke, dementia or other cognitive issues but who suffered a documented stroke within 12 years of their first survey and cognitive test in 1998.
In this group of older adults, stroke did not explain black-white differences in cognitive decline or impact cognition differently by race.
What is the link between stroke and cognitive decline, and why is this study significant?
Cognitive decline is one of the most feared aspects of aging. It increases older adults’ risk of death, disability and dependent living, and decreases their quality of life.
Stroke is a major and preventable cause of cognitive decline. Our study shows that stroke is associated with significant cognitive decline. By preventing stroke, we can reduce an individual’s risk of cognitive decline, and most strokes can be prevented. Individuals of all racial and ethnic backgrounds can ask their doctors to screen them for stroke risk factors. They can also estimate their own risk of stroke using online scoring systems, such as the National Stroke Association’s Stroke Risk Scorecard. With this information, adults and their doctors can work together to implement preventive strategies that will reduce their risk of stroke.
How can we prevent stroke?
Control your blood pressure and cholesterol. If you’re taking medication for either of these conditions, make sure you take it on a regular basis as prescribed by your doctor. Don’t smoke. If you have diabetes, make sure you’re controlling your blood sugar. And always be active, even in old age. Think about adopting a Mediterranean diet, which can reduce the risk of stroke and cognitive decline.
If you have had a stroke, it’s critical to prevent another stroke from happening because second strokes are more lethal and disabling than first strokes.
Controlling risk factors like high blood pressure, high cholesterol and diabetes, and engaging in healthy lifestyles and behaviors can prevent 80% of repeat strokes.
How can rehabilitation play a part after a person experiences stroke?
Rehabilitation after stroke can improve function and cognition. Many stroke survivors recover.
Take the next steps
- Complete the National Stroke Association Stroke Risk Scorecard to find out your stroke risk.
- Talk with your doctor if you are concerned about stroke risk factors such as blood pressure, cholesterol, smoking, diabetes or weight.
Deborah A. Levine, M.D., MPH, is Assistant Professor of Medicine in the Departments of Internal Medicine and Neurology and Research Scientist, Center for Clinical Management and Research at the VA Ann Arbor Healthcare System. She sees patients at the University of Michigan Health System. Levine’s primary research interests are the epidemiology, prevention and care of stroke and cardiovascular disease with a focus on vascular risk factors, medication adherence and health disparities. She founded the University of Michigan General Medicine Post Stroke Clinic.
For more than 160 years, the University of Michigan Health System has been a national leader in advanced patient care, innovative research to improve human health and comprehensive education of physicians and medical scientists. The three U-M hospitals have been recognized numerous times for excellence in patient care, including a #1 ranking in Michigan and national rankings in many specialty areas by U.S. News & World Report.