High blood pressure can have a detrimental effect on your brain, and that includes the possibility of mild cognitive impairment and dementia, including the most common type of dementia, Alzheimer’s disease. For many years, experts have known that high blood pressure is associated with vascular dementia, a type of dementia that develops when individuals have a series of small strokes. Now increasing evidence indicates that hypertension is linked to Alzheimer’s disease as well.
Mild cognitive impairment is a transition stage between a person’s brain changes’ effect on memory and understanding on a mild level and the more serious impact associated with Alzheimer’s disease. Not everyone who has mild cognitive impairment goes on to develop Alzheimer’s disease, but nearly everyone who has Alzheimer’s disease first experienced mild cognitive impairment. Mild cognitive impairment and dementia/ Alzheimer’s disease can result from blockage of blood flow to the brain when hypertension damages the blood vessels. High blood pressure that appears in early life can increase a person’s risk of dementia in later years.
A March 2013 study that appeared in JAMA Neurology indicated that people who control or prevent high blood pressure earlier in life may limit or delay the changes that occur in the brain associated with Alzheimer’s disease and other dementias. Among those brain changes is the accumulation of a protein called beta-amyloid. The buildup of beta-amyloid has been implicated as a potential cause of Alzheimer’s disease.
About 20 percent of the population has a specific type of gene called an APOE4, which makes these individuals more likely to have elevated levels of beta- amyloid. In this study, Dr. Karen Rodrigue, assistant professor at the University of Texas at Dallas Center for Vital Longevity, and her team found that people with APOE4 as well as high blood pressure were at greater risk of accumulation of beta-amyloid and therefore at higher risk of developing Alzheimer’s disease than individuals without APOE4 or hypertension.
Scientists have noted a link between high blood pressure and Alzheimer’s disease regarding something called white-matter lesions. When high blood pressure damages the arteries, it causes a type of scarring called white matter jesions. In the brain, white matter is involved in cell communication. When the blood vessels in the brain are impacted by white-matter lesions, it can affect memory and cognitive functioning.
In a Johns Hopkins study involving nearly one thousand adults, researchers found that the longer middle aged people with high blood pressure did not adequately control their hypertension, the more white-matter damage they incurred. Evidence of the damage was seen on brain scans. One argument for managing high blood pressure as quickly as possible is that a rapid response lowers your risk of developing dementia or Alzheimer’s disease in the future. In fact, a National Institute on Aging study discovered that patients in a study who were treated for twelve years or longer for high blood pressure had 60 percent less dementia risk than people who were never treated for hypertension.
Hypertension can silently take its toll on your brain and your cognitive functioning. To protect yourself against the possibility of dementia and Alzheimer’s disease, it’s critical to take control of your high blood pressure now.