Known as the “silent killer,” high blood pressure affects about 45% of American adults. Data from 2017 to 2018 revealed that it was higher among men than women. About 70% of Americans will have high blood pressure at some point in their lifetimes. Only one in four patients with elevated blood pressure levels will have blood pressure under control.
Medical experts call it “the silent killer” because it usually doesn’t exhibit symptoms. It does, however, increase the risk of life-threatening cardiovascular diseases, including heart failure, ischemic heart disease, and peripheral artery disease. It’s well-established that high blood pressure affects the heart, but new research indicates that it also affects brain health. Continue reading to learn what the latest research says about the relationship between high blood pressure and cognitive decline, and how you may be able to manage heart and brain health simultaneously.
The Link Between High Blood Pressure And Cognitive Changes
Several studies indicate associations between high blood pressure and cognitive decline, dementia, and possibly Alzheimer’s disease. Researchers note that the evidence is strongest between high blood pressure and cognitive outcomes during middle age. The links are less clear in older age, according to doctors. High blood pressure also increases the risk of stroke and not-so-silent stroke-like changes that can be seen on brain scans. All of those changes have been associated with cognitive alterations, such as dementia.
Why Is High Blood Pressure In Middle Age Risky For Brain Health?
Health experts have a few theories as to why high blood pressure in midlife is integral for brain health. One theory is that it represents a time of vulnerability, while another is that people with high blood pressure in midlife likely have it for a longer period of time. Some people have factors that contribute to high blood pressure for years before ever being diagnosed.
When a doctor diagnoses high blood pressure, a person has reached a tipping point. They have had relatively normal blood pressure (even if slightly elevated) and the body has adjusted to maintain normal changes under pressure. All of a sudden, though, the body can no longer adapt and some sort of intervention is necessary. Diet and exercise can help manage blood pressure, but some people require medication if they cannot keep levels in check with natural remedies.
By examining data, researchers found that the trajectory for developing high blood pressure was similar. People generally have stable blood pressure until the systolic pressure (top number) approaches a range of 120 to 125 millimeters of mercury (mmHg). Once a person passes that threshold, blow pressure increases at a relatively rapid rate until hypertension is diagnosed. Other factors that increase hypertension include chronic stress, smoking, lack of sleep, poor diet, and obesity.
What Happens To The Brain In A Person With High Blood Pressure?
Hypertension can negatively impact the brain in several ways. Long-term hypertension impacts arteriolar and arterial health over time, which increases the risk of stroke or stroke-like changes that can impact overall cognition. Years of elevated blood pressure levels may cause small clots that make their way to the brain. The accumulation of plaque in the arteries also reduces blood flow.
Researchers note that brain matter tries to adapt to the lack of oxygen that stems from partially blocked arteries. The brain grows support tissue around itself, but it isn’t neurological tissue. It is more akin to scar tissue that develops due to a lack of oxygen. Unfortunately, it doesn’t have the capacity or function that brain cells or neurons have. Although this is an adaptive response, the adaptation can cause its own harm because it is trying to defend itself in a state of low oxygen.
That gradual loss of cognitive function over time can lead to the loss of overall brain matter mass, and occasionally, dementia. Health experts believe that high blood pressure can change the efficacy of blood-brain barrier function. It may even impact how the glymphatic system functions. The glymphatic system, not the lymphatic system, is a pathway in the brain that seemingly removes waste from the central nervous system. It is a newer concept that is being discussed in the medical field. By removing toxins from the brain, you may reduce the risk of Alzheimer’s disease.
The Takeaway
As of right now, most of the evidence from observational trials shows that there is a cognitive benefit from managing blood pressure. Physical activity and dietary changes are promising for both cardiovascular and cognitive outcomes. A meta-analysis from 2022 found that higher rates of physical activity were associated with decreased risk of all-cause dementia. It also improved vascular function and decreased risk factors for hypertension.
High blood pressure is but one of the risk factors for cognitive decline that you can control. You can reduce blood pressure via a combination of healthy lifestyle habits, and medication when necessary. It is never too early to talk to your doctor about your blood pressure. Do what you can to keep it in a healthy range, and your heart and brain will thank you.
