George Howard, DrPH
Photography: Steve WoodThe United States is seeing an upward trend in the age distribution of the general population. By 2050, it is anticipated over 50 percent of stroke events will occur in those over the age of 75. However, the majority of stroke-related studies focus on populations that are younger than this age.
Researchers at the University of Alabama at Birmingham evaluated the association of stroke risk factors to learn whether any varied with older age. Results published today in the American Academy of Neurology’s medical journal, Neurology, found the impact of certain stroke risks differed between age groups. Specifically, high blood pressure and diabetes were more significant factors in younger populations, 45-69, than in those older than 74.
“Previous studies have assumed that the relative impact of certain risk factors remained the same no matter one’s age,” said George Howard, DrPH, professor in the UAB School of Public Health and first author. “Understanding how risk factors change with age can help health practitioners better identify those at a higher risk for stroke as well as create risk appropriate interventions.”
The study followed 28,235 people who had never had a stroke and were enrolled in UAB’s Reasons for Geographic And Racial Differences in Stroke, or REGARDS, cohort study. Participants were first evaluated for risk factors that included high blood pressure, diabetes, cigarette smoking, atrial fibrillation, race, heart disease and left ventricular hypertrophy, which is the thickening of the heart’s left ventricle. The participants were followed an average of 11 years. During the study, 1,405 strokes occurred.
The Reasons for Geographic And Racial Differences in Stroke, or REGARDS, project, sponsored by the National Institutes of Health, is a national study focusing on learning more about the factors that increase a person’s risk of having a stroke.
Findings showed people with high blood pressure in the younger group had an 80 percent higher risk of stroke than others their age. Additionally, younger participants with diabetes were twice as likely to have a stroke. In the older group, the risk of having a stroke caused by high blood pressure decreased to 50 percent and 30 percent for those with diabetes.
Stroke risk factors such as cigarette smoking, atrial fibrillation and left ventricular hypertrophy did not have an age-related change.
“It is important to note that our results do not suggest that treatment of high blood pressure and diabetes becomes unimportant in older age,” Howard said. “Such treatments are still very important for a person’s health. But it also may be wise for doctors to focus on managing risk factors such as atrial fibrillation, smoking and left ventricular hypertrophy as people age.”