June 10, 2011
Richard Libman, MD
National patterns of racial and regional differences in stroke incidence are similar to those for stroke mortality; however, the magnitude of these differences in incidence appears smaller, according to a study appearing in a recent issue of the Annals of Neurology. Known as REGARDS (the REasons for Geographic And Racial Differences in Stroke), the national study further elaborates on the geographic variation in the incidence of stroke, stroke risk factors and cognitive impairment, a condition that includes problems with memory, language or other mental functions.
It has been known for some time that the "stroke belt" is a geographical region with a significantly higher incidence of brain attacks. Stroke by itself is a major contributor to cognitive impairment and dementia. Furthermore, such risk factors for stroke as high blood pressure and diabetes are independent risk factors for cognitive impairment. In the REGARDS study, living in the stroke belt was also a risk factor for cognitive impairment.
The important message is that careful analysis of what makes the stroke belt different from other areas of the country can lead to more insight into what is causing the cognitive impairment, and, hopefully, result in effective preventive measures and treatment.