This is the third post in a series on chronic diseases in the US.

Statistics

High blood pressure (hypertension) is the 5th leading cause of death in the US. In 2019 half a million people in the US died with hypertension as the cause or major contributing cause. Two thirds of all strokes and half of all heart attacks are caused by hypertension. The old definition of hypertension was a systolic blood pressure of 140 or greater and/or a diastolic blood pressure of 90 or greater. There is a new definition of hypertension that we will talk about later, but by the old definition, one out of every 4 people in the US have uncontrolled hypertension. By the new definition nearly half of people in the US have hypertension.

Definitions

The medical term for high blood pressure is hypertension. Blood pressure has two components. The systolic pressure is the pressure when the heart beats, forcing blood out of the left ventricle into the arteries of the body. The diastolic pressure is the pressure left in the arteries between beats. Both are equally important, and an increase in either one (or both) increases risk.

It has been known for a long time that there is a continuous increase in risk of cardiovascular disease and stroke as blood pressure rises. The lower your blood pressure the lower your risk. The spot on that blood pressure vs risk curve where we define the disease hypertension is arbitrary. The vast majority of deaths, strokes and heart attacks come from systolic blood pressures of 140 or higher and/or diastolic blood pressures of 90 or higher.

The new definition of hypertension

Blood pressure categories in the new guideline are:

• Normal: Less than 120/80 mm Hg;
• Elevated: Top number (systolic) between 120-129 and bottom number (diastolic) less than 80;
• Stage 1: Systolic between 130-139 or diastolic between 80-89;
• Stage 2: Systolic at least 140 or diastolic at least 90 mm Hg

There are no new data on the continuous increase in risk as blood pressure rises. The American Heart Association and other associated groups have simply decided to change the spot on the risk curve where hypertension is defined. They point out that the risk of cardiovascular disease is 3.5 times higher in the Elevated category than in the normal category. That sounds like a lot, but three times a very small risk is still a very small risk.

Measurement of blood pressure

High blood pressure has no symptoms, so you don’t know if you have it unless you measure it. In order to figure out where you are on the blood pressure risk curve, you have to know what your average blood pressure is. Blood pressure should not be measured until you have been sitting quietly for 5 minutes. That clearly does not happen the vast majority of the time when the nurse or medical assistant takes your blood pressure in your doctor’s office. More likely you have rushed to get there, had trouble finding a parking place, walk into the office already agitated and anxious, and the nurse takes your blood pressure as soon as you sit down. That is a recipe for having a falsely elevated blood pressure!

Home blood pressure measurement

The best way to determine your average blood pressure is to measure it at home. There are lots of very reliable reasonably priced home digital blood pressure monitors. Choose one that has a cuff that goes on your upper arm, not your wrist. The wrist blood pressure monitors are not very accurate. Also check that the cuff is the right size for your upper arm. If your upper arm is very large, then you will need a monitor with an extra large cuff. It is a good idea to measure the diameter of your upper arm before you buy a blood pressure monitor. Here is a link to an article by Forbes Health that rates the top ten home digital blood pressure monitors: Best Blood Pressure Monitors of 2022. Note that the highest ranked one is not the most expensive one. Any of the OMRON monitors are good, so if that brand is what is available in your local pharmacy, that brand would be fine.

Measure your blood pressure twice a day for at least two or three weeks. You should sit quietly in a chair for five minutes before you measure your blood pressure. You should not measure your blood pressure right after you have had your morning coffee. Either measure it before coffee (or tea) or about two hours after your last cup. All of the good monitors keep a record of your blood pressures, and some of them will calculate the average for you.

What to do based on your average home blood pressure

Normal (less than 120 systolic and less than 80 diastolic): You don’t need to make any diet or lifestyle changes based on your blood pressure

Elevated (systolic 120-129 and less than 80 diastolic): Although your risk of cardiovascular complications is a little higher than if your systolic pressure was less than 120, it is not much higher. You might want to make some modest diet and lifestyle changes (which I will discuss later). You definitely do not need blood pressure medicine.

Stage 1 (systolic between 130-139 or diastolic between 80-89): This used to be considered normal by the old definition of hypertension. Blood pressure at this level bumps up your risk of stroke or cardiovascular disease by a bit more than the elevated category but it still would be considered moderate risk. You would definitely want to make some diet and lifestyle changes and if you did that you would likely still not need blood pressure medicine.

Stage 2 (systolic 140 or greater or diastolic 90 or greater): The risk of stroke or heart disease is substantially high and gets progressively higher as the blood pressure increases. You still should do diet and lifestyle changes, but you probably will also need blood pressure medicine. If you have stage 2 hypertension, you should definitely see your doctor.

Risk factors for hypertension

Surprise, surprise! The risk factors for hypertension are almost the same ones that increase your risk of type 2 diabetes, heart disease, cancer, and stroke. They are:

• Heredity (not simple and involving multiple genes each contributing a tiny part)
• Increased body fat, particularly increased waist circumference
• Sedentary lifestyle
• Eating high sugar, high carbohydrate processed foods
• Eating too much salt

Diet and lifestyle changes to decrease blood pressure

• Reduce sodium in your diet. That means no added salt and staying away from high sodium foods. Here is a link to an article from drugs.com describing a 2 gram sodium diet: 2 Gram Sodium Diet. If you are simply not willing to get rid of added salt completely, switch to Morton’s Lite Salt. It is half sodium chloride and half potassium chloride. It tastes exactly like salt but has half the sodium of regular table salt.
• All the other diet and lifestyle changes that would reduce blood pressure I have discussed in previous posts. Here are links to those posts: How to Lose Weight and Keep it Off. The Psychology of Eating and How to Use It to Your Advantage. Good Nutrition: A Review of the Evidence. Type 2 Diabetes Mellitus: Anatomy of an Epidemic.

Bottom Line

• High blood pressure, even very high blood pressure has no symptoms. Because of that everyone should determine their average blood pressure at least once a year.
• Home blood pressure measurement is the most accurate way to know your average blood pressure.
• Measure your blood pressure twice a day for at least 2-3 weeks and calculate the average.
• If your average blood pressure is in the elevated range or higher, then diet and lifestyle changes will help reduce it.
• If you have stage 1 or 2 hypertension you should see your doctor.