High Blood Pressure and Dementia Risk

Dr. Amanda Wiggins
Xtend-Life Research Scientist

Dr. Amanda Wiggins works with Xtend-Life as the Chief Research Scientist, where she shares her knowledge of research, science and wellness.

In this Health Article, we look at the link between high blood pressure and the risk of developing cognitive problems later in life.

It is common knowledge that high blood pressure can lead to heart attacks and strokes. It is less well-known that high blood pressure is also a risk factor for developing mild cognitive impairment and dementia.

Research from decades of observational studies has conclusively shown that having high blood pressure increases the risk of mild cognitive impairment, vascular dementia, and even Alzheimer's disease. Both systolic and diastolic hypertension are risk factors, and in general, the higher the pressure and the longer it persists without treatment, the greater the risk.

Details of the exact increase in risk vary depending on the study. One study of 2,505 men between the ages of 71 and 93 found that those with systolic blood pressure of 140 mm Hg or higher, were 77% more likely to develop dementia, than those with normal systolic blood pressure (below 120 mm Hg).

In another study, researchers analysed blood pressure and cognitive function in more than 7,000 adults with an average age of 59. Data collected over a four-year period showed that those who had uncontrolled high blood pressure had a faster decline in cognitive performance than those who had normal blood pressure. Even those with pre-hypertension - slightly elevated blood pressure, had a faster decline in cognitive function than those with normal blood pressure.

The evidence seems to point to the biggest risk being persistent, uncontrolled blood pressure in the middle of life (ages 40-60). No matter which studies you look at, all studies in this area reinforce the need to maintain normal blood pressure levels throughout life, no matter what your age or stage.

How Does it Work?

Researchers aren't 100% clear on why having high blood pressure increases the risk of cognitive decline and dementia.

One aspect is obvious, high blood pressure can damage blood vessels making them weaker or narrower, and more likely to burst or become blocked. This restricts blood supply to parts of the brain, so not enough oxygen and nutrients can reach brain cells, leading to cell death and damage in parts of the brain.

High blood pressure also increases the risk of strokes. When we think of strokes, we normally think of the big, catastrophic strokes that render someone with impaired speech or movement. However, strokes are not necessarily big. Often strokes can be so tiny that a person doesn't even know that they are having them. Having lots of tiny strokes (or a few big ones) greatly increases the risk of cognitive decline and dementia.

With regards to the link between high blood pressure and Alzheimer's specifically, it is thought that damage to brain tissues due to blood vessel damage may lead to increased levels of inflammation, which speeds up the onset of full-blown dementia. In one recent study, older people with higher blood pressure were more likely to have brain lesions - areas of dead tissue and more likely to have "tangles" - the twisted strands of protein that are considered markers of Alzheimer's disease.

How Effective Is Lowering Blood Pressure?

There are a lot of studies that look at this issue and while the details vary considerably from study to study, one thing is clear, lowering high blood pressure will lower your risk of cognitive impairment and dementia.

The SPRINT-MIND study is one of the most talked-about and recent studies looking at this issue. It showed that lowering systolic blood pressure to below 120 mm Hg lowered the risk of mild cognitive impairment, a common precursor to Alzheimer's, compared to the control group, which had systolic blood pressure between 120 - 140 mm Hg. The key message from this study is that lowering your blood pressure to below 120 mm Hg should be the goal when it comes to supporting healthy brain function.

The exact amount of risk reduction is really hard to nail down. Various studies have reported that anti-hypertensive treatments reduce the risk of dementia from anywhere between 20% to about 60%. Another study reported that each year of anti-hypertensive therapy resulted in a 6% decline in the risk of developing dementia. Those who'd been on anti-hypertensives for 12 years or more had a 65% lower risk of Alzheimer's than those who had uncontrolled high blood pressure.

How to Control Blood Pressure in the Normal Range

You can reduce your risk of developing cognitive impairment and dementia by lowering your blood pressure to within the normal range. The first step is to know your blood pressure by having it tested regularly. You can have this done by a health professional, or you can purchase an at-home blood pressure machine. Either way, knowing whether your blood pressure is consistently elevated or not, is an important first step.

The best ways to achieve blood pressure in the normal range is through:

If these changes are not sufficient on their own, consider adding a supplement such as Xtendlife's VasQFlow which is packed with natural ingredients that are proven by science to support healthy blood flow and healthy blood pressure.