Researchers reporting in the journal Neurology have found that elevated blood pressure as we age contributes to stroke risk and memory loss associated with cognitive decline. Stroke is the fourth leading killer of adults in the US, and loss of cognitive abilities leading to dementia ranks in the Top Ten causes of mortality. Hypertension and other known stroke risk factors also increase the risk of developing cognitive problems, even among people with no history of the vascular disorder. Lowering high blood pressure to within an optimal range can have a profound benefit in preventing stroke incidence and averting memory-robbing cognitive decline.
Lead study author, Dr. Frederick Unverzagt, a psychiatry professor at the Indiana University School of Medicine in Indianapolis, analyzed the findings from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study. The study followed 23,752 people with an average age of 64, who were free of stroke and cognitive problems at the start of the study. Participants underwent a Framingham Stroke Risk Profile, typically used to determine people's risk of stroke by measuring their age, blood pressure, education level, history of heart disease, smoking and diabetes status.
Lowering Blood Pressure Directly Decreases Risk of Cognitive Impairment
After four years into the trial, 1,907 people had developed memory and thinking problems, indicative of cognitive decline and a precursor to Alzheimer's disease. The study found that the higher a person's score on the Stroke Risk Profile, the greater the chance of developing cognitive issue after a four year period. Dr. Unverzagt commented "Overall, it appears that the total Stroke Risk Profile score, while initially created to predict stroke, is also useful in determining the risk of cognitive problems."
The trial determined that older age and thickening of the heart muscle (leading to increased blood pressure) were the most important independent factors with cognitive issues. For each 10 mm Hg increase in systolic blood pressure, cognitive decline risk increased by 4.1 percent. Additionally, each 10-year increment in age doubled the risk of cognitive impairment by about 30 percent.
Further evidence connecting lifestyle factors and cognitive decline is published in the journal Diabetes Care. Researchers at the Beth Israel Deaconess Medical Center (Harvard Medical School) have found that diabetes is a strong risk factor that promotes cognitive decline, and for the first time they provided the missing link to explain memory loss and degradation of normal thought processes.
Scientists report that high blood sugar and insulin surges cause the release of two adhesion molecules in the brain causing inflammation and triggering a series of events that damages blood vessels and triggers brain tissue atrophy. Critical functions such as decision-making, language, verbal memory and complex tasks are most affected by this health-robbing cascade of chemical reactions. Regular monitoring and maintenance of blood pressure and blood sugar along with rigorous measures to control these biomarkers within optimal range can prevent stroke and halt the process of cognitive decline.