Blood Pressure Influences Your Risk for Alzheimer's Disease
Are you monitoring your blood pressure levels? Research shows that those who have uncontrolled blood pressure have a higher risk of neurodegenerative diseases, particularly Alzheimer's.
STORY AT-A-GLANCE
High blood pressure affects nearly half of American adults. A study shows that it increases the risk of Alzheimer's disease by 42% in untreated cases compared to people without hypertension
Blood pressure damages brain capillaries when elevated, causing blood clots, leakage and restricted blood flow, which leads to cognitive issues and stroke
Normal blood pressure is 120/80 mm Hg. For accurate readings, measure it while lying down in the evening after resting for 20 minutes
Vitamin D deficiency increases blood pressure by affecting the renin-angiotensin-aldosterone system. Studies have also shown that people have higher blood pressure levels during winter months
Contrary to common medical advice, reducing salt intake only temporarily affects blood pressure and can lead to mineral imbalances affecting vascular relaxation and stress levels
High blood pressure, also known as hypertension, is one of the most common health conditions affecting Americans today. According to the American Heart Association (AHA), almost half of the adult population has high blood pressure. What's worse is that it's dubbed as "the silent killer," as many don't know they have it.
Research1 has shown that hypertension increases your risk for numerous health conditions, such as chronic kidney disease, atrial fibrillation, heart failure and aortic syndromes. Now, a study shows that high blood pressure increases your risk for dementia, specifically Alzheimer's disease.
High Blood Pressure Increases Your Risk for Alzheimer's Disease by 42%
In a meta-analysis published in Neurology,2 researchers established that hypertension increases the risk of dementia. However, how high is the likelihood? This is the question they sought to measure. Specifically, they investigated how mid-life hypertension affects the development of Alzheimer's disease and non-Alzheimer's dementia. They also analyzed how much risk is reduced when anti-hypertensive interventions are implemented.
For the analysis, the researchers selected 14 community-based longitudinal studies from a database monitoring cognitive change and dementia over time. Each study came from a different country to paint a global picture of this health issue.
A total of 31,250 participants were selected for the study after filtering out factors such as having a dementia diagnosis at baseline. The follow-up durations for all studies ranged between two and 15 years. Analysis was done using special software, and once completed, factors such as blood pressure readings, and whether the participants were taking hypertensive medications or not were considered for the results.3
Once the data was collated, the researchers noted the differences in Alzheimer's risk for people with treated and untreated hypertension:4
"We found that individuals aged 60 years or older with untreated hypertension had a 42% increased risk of all-cause dementia compared with those without hypertension and a 26% increased risk compared with those with treated hypertension …
AD (Alzheimer's disease) has distinct familial, genetic and environmental risk factors compared with other dementias, as well as specific symptomatic and disease-modifying treatments. As such, risk mitigation strategies for AD may need to be different to other dementias, and it is important that the particular effect of BP and antihypertensive use on AD risk, in addition to all-cause dementia, be understood."
Understanding the Process Behind Blood Pressure-Induced Dementia
Based on the findings, it's clear that blood pressure affects cognitive health. But how? Blood flows into your brain via an extensive network of capillaries, which are the smallest type of blood vessels. According to the Cleveland Clinic, they form the blood-brain barrier, helping deliver nutrients to the brain while simultaneously preventing the entry of toxins. Anatomically, they're very small, having a diameter of only 8 to 10 micrometers.5
What's more, capillaries are sensitive to changes in pressure. In fact, many people already get broken capillaries when severely coughing or vomiting. These usually manifest as little red dots on your skin that heal on their own.6 But when the pressure in the capillaries inside your brain increases, that's a different matter.
According to the Mayo Clinic, high blood pressure raises the risk of blood clots forming in the arteries leading to the brain, which leads to stroke. In other cases, high blood pressure damages the blood vessels, causing them to leak or contract, limiting blood flow to the brain. Eventually, these changes cause cognitive issues.7
This hypothesis is also supported by a study8 published by Cedars-Sinai researchers. According to their findings, high blood pressure increases the risk of Alzheimer's disease or another type of dementia.
Are You at Risk for High Blood Pressure?
The only way to know if you have high blood pressure is to have your levels checked, ideally at regular intervals at home, and during medical checkups. But, how do you interpret the results?
For those unfamiliar, a blood pressure reading has two numbers. The top number is the systolic blood pressure (SBP), while the lower number is diastolic blood pressure (DBP). The SBP value refers to the highest pressure in the arteries, which occurs when the heart ventricles contract.
The DBP value is the lowest arterial pressure that happens during the resting phase of your cardiac cycle. Once you have your readings, refer to the table below to see your blood pressure's current health state:9
According to the AHA and American College of Cardiology, normal blood pressure for adults is 120/80 mm Hg. However, your blood pressure levels fluctuate throughout the day. Clinical researcher Dr. Stephen Juraschek said that the "gold standard" for accurate measurements is ambulatory blood pressure monitoring, but he noted that the issue here is that you're required to wear a device for 24 hours, even while you sleep.10
To get an accurate reading, it's better to measure your blood pressure while lying down at nighttime. From Juraschek's research, he noted that this approach is one of the best predictors of cardiovascular disease. However, it will disrupt your sleep, which will have negative consequences to your health. For a more practical approach, take your blood pressure at home in the evening when you can lie down for 20 minutes.
Also make sure you're using the correct cuff size. And, if taking your blood pressure in a seated position, make sure your arm is supported on a desk with the midcuff positioned at the heart level to ensure accurate measurements. The wrong arm position can result in a misdiagnosis of hypertension.11
Managing high blood pressure is a vital part of heart health. Unfortunately, once people discover their blood pressure isn't within the normal range, medication is often the first course of action, and this not the wise path to take. Implementing healthy lifestyle changes alone already have a significant impact on your blood pressure. Simply put, there's no need for you to resort to drugs that come with a long list of adverse side effects.
Quit Vaping and Smoking
For those who are vaping, the risks to your cardiovascular health are similar to smoking cigarettes, which most people know is already bad for their health. Published research has linked vaping to increased blood pressure and arterial stiffness.12 When your arteries are stiffer, the heart works harder to pump blood throughout the body since the arteries don't expand as easily. This eventually leads to heart muscle thickening (hypertrophy) and eventually heart failure.
In another study, researchers followed 175,667 participants with an average age of 52 for 45 months. They noted that those who used e-cigarettes at any point in their lives are 19% more likely to develop heart failure compared to those who didn't vape.13
If you're having trouble quitting vaping or smoking, there are different ways to help you quit. I recommend increasing your physical activity, such as walking, to help distract you from cravings and reduce stress, which is often a trigger for getting another smoke. Mindfulness activities, such as yoga, meditation and the Emotional Freedom Techniques (EFT) will also help you manage stress and the cravings to smoke.
Not Getting Enough Vitamin D Affects Your Blood Vessels
Vitamin D is one of the most important nutrients for optimal health, and if you don't get enough of it, your blood pressure is affected. This was observed in a study published in the International Journal of Molecular Sciences.14 Moreover, the researchers noted that blood pressure levels across populations are lower in the summer compared to during winter. What is the mechanism behind this?
The researchers dove deeper into the connection between vitamin D and hypertension, noting that a deficiency increases RAAS (renin-angiotensin-aldosterone system) activity, which is a process that maintains long-term blood pressure.
Essentially, the increased plasma renin concentration predisposes you to arterial hypertension and decreased glomerular filtration rate, which subsequently affects the cardiovascular system. Interestingly, vitamin D deficiency affects blood pressure through the thyroid gland:15
"Vitamin D is involved in calcium homeostasis by stimulating the production of calcium transporters, increasing calcium reabsorption in the kidney, and inducing the osteoclastic calcium release in bones.
Therefore, a vitamin D deficiency can result in a decreased concentration of Ca2+ in the plasma, which will lead to the secretion of parathyroid hormone (PTH) from the chief cells in the parathyroid gland to counteract this. Several epidemiological studies have shown that elevated PTH levels were associated with higher SBP and DBP values and a higher prevalence of HT in general."
Not surprisingly, the country in which you live will affect your vitamin D levels. In a study published in Nutrients,16 researchers showed that people who live at latitudes greater than 40 degrees don't have enough sunlight exposure for months to get enough vitamin D compared to those who live on the equator.
If you live in a place where there's not enough sunshine for months, it would be wise to take a vitamin D3 supplement. To maximize its effectiveness, increase your intake of magnesium, calcium and vitamin K2 as well.
For everyone else living in a place with adequate sunlight, the best way to optimize your vitamin D levels is by going outside, but there are some caveats to this. If you've been eating a diet high in linoleic acid (LA), it's important you minimize your intake of it to less than 5 grams per day. If you can get it below 2 grams, even better. That's because LA embeds into your skin and oxidizes when exposed to sunlight. Once this happens, inflammation and DNA damage occurs.
As you start the process of removing excess LA from your body, which can take anywhere between four to six months, I recommend you avoid sunlight during solar noon. In the meantime, you can expose your skin during early morning and late afternoon when the sun's rays aren't as strong. While this isn't optimal, it will keep you safe as you work toward eliminating LA from your body.
Taking low-dose aspirin, astaxanthin and/or molecular hydrogen, as well as applying niacinamide cream on your skin will also provide added protection against skin damage.
For optimal health, your blood vitamin D level should be between 60 and 80 nanograms per milliliter (ng/mL). Get your blood tested to determine your current level and how much supplementation you might need.
Don't Fear Increasing Salt Intake
You've probably heard of the conventional advice to cut back on your salt intake when you have high blood pressure, but is there any truth to this saying? While the National Institutes of Health (NIH) espouses that adopting this strategy will help manage blood pressure,17 the truth is that it only works temporarily.
Salt, also known as sodium, is an important electrolyte in your body. Having a stable salt level helps your body maintain an appropriate blood volume, which helps proper circulation. When salt suddenly decreases, the blood volume is reduced and impedes your body's ability to eliminate waste. In addition, your body goes into a defensive state by preventing your kidneys from excreting the remaining sodium.
By retaining sodium, your body increases blood volume, but the downside is that vasoconstriction increases to bring blood pressure back up. In addition, your body begins to excrete potassium and magnesium instead, which are minerals important for vascular relaxation.
Once your potassium and magnesium levels are running low, your body begins to increase sympathetic nervous system activity, which is responsible for the fight-or-flight response, leading to stress. As noted in a study18 published in the Journal of Preventive Medicine & Public Health, stress (especially when chronic) contributes to hypertension.
Your body will benefit from an intake between 1,500 and 3,500 mg of sodium per day, depending on your physical activity. To be sure, I recommend getting a fasting chemistry profile showing your serum sodium. The ideal level is around 139 (the optimal range being 136 to 142).
Also remember to increase your potassium intake as well. It works together with sodium, creating a crucial homeostasis known as the sodium-potassium ratio. Research shows that regardless of sodium intake, higher potassium levels are associated with lower blood pressure.19
As a general rule, your potassium intake should be five times more than sodium. You'll find potassium in foods such as oranges, cantaloupe, grass fed yogurt and spinach.20
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