High blood pressure is also known as hypertension. High blood pressure is common in older adults, because our blood vessels become less elastic, or stiffen, as we age. This increases resistance to the flow of blood, and blood pressure increases. National surveys show that over half of people aged 65 and older have high blood pressure. People with high blood pressure are at increased risk of heart attacks, strokes, kidney disease, eye diseases, and other problems.
High blood pressure in older adults is generally caused by the blood vessels becoming less elastic. The walls of the aorta and other large blood vessels stiffen, which increases resistance to blood flow. (The aorta is the largest blood vessel in the body. It directs blood directly from the heart to the rest of the blood vessels throughout the body.) The ability of blood vessels to expand or dilate also becomes less efficient with age, which adds to the resistance to blood flow. In addition, as people age, their blood vessels often become coated with fatty tissue that can narrow the diameter of the vessel, a condition called atherosclerosis (see
Heart Disease).Changes in the regulation of salt and water also play a role in the development of high blood pressure. Approximately two thirds of older adults are sensitive to salt, so that their blood pressure goes up with increased salt intake. This is especially a problem for people with certain types of kidney disease.
Other important factors in the development of high blood pressure include obesity, physical inactivity, and other diseases such as diabetes or kidney disease.
Blood pressure is measured in millimeters (mm) of mercury (Hg). One mm of mercury is the pressure needed to push a column of mercury one mm up a glass tube.
Each blood pressure measurement has two parts, a top number and a bottom number. The top number, which is called systolic, is the pressure when the heart is contracting and pushing blood out of the heart into the arteries. The bottom number, which is called diastolic, is the pressure when the heart is relaxing and letting blood flow into it.
Normal systolic (ie, top number) pressure is about 120-130 mm Hg. Normal diastolic (ie, bottom number) pressure is about 70-80 mm Hg. In early hypertension, the systolic pressure is usually 120-139, and the diastolic pressure is about 80-89. As hypertension progresses, the systolic pressure goes up to 140-159 and the diastolic pressure to 90-99. In even more advanced hypertension, the systolic pressure can be 160 or higher, and the diastolic pressure can be 100 or more.
People with high blood pressure usually don’t feel sick or experience symptoms. So, you don’t know if you have high blood pressure unless it is measured.
Blood pressure measurements become much more variable as we get older. Blood pressure might be high one day and normal on another. For this reason, health care providers like to take several blood-pressure readings on each of several office visits, and then average the results before deciding if you have high blood pressure.
Some people get nervous when they go to the doctor, which may cause normal blood pressure to go up. This is called "white-coat" hypertension. In this case, your health care provider may ask you to take your blood pressure several times at home and report the average. Many types of accurate and easy-to-use blood pressure monitors for home use are available at a reasonable cost.
Once high blood pressure has been diagnosed, your health care provider will want to check for any underlying illnesses that may have caused it or are being caused by it (eg, heart problems, kidney disease, diabetes, or eye problems). This involves a routine history and physical examination, as well as blood and urine tests.
Heart disease is generally the most common problem related to high blood pressure. So your health care provider may focus particularly on risk factors for heart disease, such as obesity, family history, high cholesterol level, lack of exercise, heavy drinking, and poor diet.
Because high blood pressure can cause so many problems, treatment is important. The goal of treatment is to lower blood pressure enough so that your risk of heart disease and stroke is lowered. This generally means having a systolic pressure of around 135-140 mm Hg or less, and a diastolic pressure of around 85-90 mm Hg or less. However, if you have diabetes or chronic kidney disease, your health care provider will work with you to get your blood pressure below 130/80. Also, although maintaining normal systolic and diastolic pressures is important, the systolic pressure is the one most associated with heart disease and other problems in older adults. In most cases, blood pressure is lowered gradually over days or weeks.
Treatment usually begins with changes in diet and lifestyle unless your blood pressure is very high and/or you have other conditions which indicate that medications should be started right away. Many people can benefit a great deal from making some changes in their lifestyle, including the following:
- Lowering the amount of dietary salt and fat
- Drinking alcohol only in moderation
- Quitting smoking
- Exercising
- Losing weight (if needed)
Lifestyle changes may be all that is needed for older adults that have systolic pressure measurements of 140-159 mm Hg systolic and diastolic measurements of 90-99 mm Hg. Lifestyle changes are also an important part of treatment when medication is needed. Even relatively minor changes in lifestyle can help. For example, some research has shown benefits from only minor reductions in salt intake and long-term weight loss of only 8-10 pounds.
Drugs are generally used to lower blood pressure in more severe cases (eg, systolic greater than 160 or diastolic greater than 100) or when lifestyle changes alone are not enough. Often, the first type of medication used is a diuretic (ie, "water pill"), which lowers blood pressure by lowering the overall amount of fluid in the body. The most commonly used diuretics are from a class of drugs known as thiazides. Thiazide diuretics lower blood pressure and decrease the risks of stroke, heart disease, and early death. They are relatively safe and produce fewer side effects than some other more complex drugs. Thiazide diuretics need to be taken only once a day, and they are relatively inexpensive so they are more economical over the long run.
Other drugs used to treat high blood pressure include calcium channel blockers, ACE inhibitors, beta blockers, and alpha blockers. These drugs work in different ways than diuretics do. They are sometimes used when there are underlying diseases (eg, diabetes or heart disease) in addition to high blood pressure. They may also be added to diuretic treatment programs, when diuretics alone are not enough to correct the high blood pressure. Your health care provider and pharmacist can provide more information about these various drugs and whether they may be appropriate for you.
Once your blood pressure is back to normal levels, your doctor may want to gradually lower the dose of your medication(s). This ensures that you receive the smallest dose necessary to maintain a normal blood pressure.
Drug complications
Many people worry about using drugs to treat high blood pressure, especially when they don’t feel sick. However, the overwhelming consensus from medical research is that drug treatment for high blood pressure is safe and effective in older adults. Still, as in all chronic conditions, in high blood pressure, it is important to balance the clear benefits of drug treatment with the potential for drug complications that can affect function and quality of life.
One particular possible complication is a sudden drop in blood pressure, which can cause you to pass out and fall, potentially breaking a bone. Unsafe drops in blood pressure happen most commonly after meals or while getting up after sitting or lying down (see also
Walking and Falling). This potential for a drop in blood pressure is one reason that drug treatment is started at low doses and increased slowly and carefully. In addition, when you are on medications that can lower your blood pressure, you should rise from a lying or sitting position slowly so that your body can adapt.Another possible complication of drug treatment for high blood pressure is loss of blood potassium. This can be a problem from treatment with diuretics, especially at higher doses. Low levels of blood potassium can lead to problems with heart rhythm or blood glucose (sugar). Your health care provider may check your potassium levels frequently during treatment and may recommend potassium supplements. Some foods (eg, bananas) are also good sources of potassium. However, because other medications often used for the treatment of high blood pressure can make you retain potassium, it is always important to check with your health care provider before taking extra potassium or replacing salt with a salt substitute that contains potassium.
Long-term monitoring and maintenance
You’ll need to visit your health care provider periodically so that your progress can be monitored and your medication adjusted if necessary. In addition, your health care provider will watch for other problems that may develop related to the high blood pressure or to effects of the medication (eg, low blood potassium). You should also routinely take blood pressure measurements at home and keep a written record. Sticking with your treatment is important, whether it means changing your lifestyle, taking your medications consistently, or both. Remember, achieving your blood-pressure goal may take many months, and maintaining a normal blood pressure usually requires a consistent effort.
Most blood pressure treatment is done gradually over time. However, there are a few emergency situations involving high blood pressure. These are situations in which blood pressure gets very high and causes sudden damage to the brain, heart, or other organs. Unlike most high blood pressure situations, these emergencies are associated with symptoms and signs of problems, which vary depending on the organs involved. In these rare emergencies, your physician may admit you to the hospital for immediate treatment and continuous blood pressure monitoring. The goal is to get your blood pressure down to a reasonable level quickly (eg, over 6-24 hours) to prevent any further organ damage.
If you don’t have high blood pressure, it can be helpful to follow the guidelines mentioned earlier related to lifestyle to keep your blood pressure at a normal level as you get older.
AGS Foundation for Health in Aging
The Empire State Building, 350 Fifth Avenue, Suite 801 New York, NY 10118
(212) 755-6810 Tel, (212) 832-8646 Fax, (800) 563-4916 Toll Free, staff@healthinaging.org.