How you can help your doctor treat your high blood pressure.
* You can't ignore high blood pressure; it won't simply go away.
* It can be effectively treated.
* Treating high blood pressure may prevent a heart attack, stroke or kidney failure.
With these facts in mind, this booklet will help you learn how treating your blood pressure can mean a longer, healthier life.
What is High Blood Pressure?
When a doctor takes your blood pressure, two numbers are recorded: an upper one, called the systolic pressure, and a lower one, called the diastolic pressure.
For example, 120 (systolic)/80 (diastolic)
Systolic pressure is the blood pressure in the arteries when the heart is pumping blood; diastolic pressure is the pressure in the arteries when the heart is resting and filling with blood for the next beat.
High blood pressure in adults is defined as a systolic pressure of 140 mmHg (millimeters of mercury) or greater and/or a diastolic pressure of 90 mmHg or greater. An elevated pressure requires attention because the risk of a cardiovascular complication is increased.
Blood pressure levels change from minute to minute, with changes in posture, exercise, degree of tension, smoking and sleeping. Because of these changes, a doctor will usually take several readings over a period of time before making a judgment about high blood pressure.
High blood pressure (called hypertension by physicians) is not "nervous tension." People who have high blood pressure aren't necessarily overanxious, compulsive or "nervous." In fact, a person may have very high blood pressure and not even know it. That's because high blood pressure--in the early stages--may have few, if any, symptoms. An early morning headache does occur in some people.
High blood pressure affects people of all ages; it's most commonly seen in people over 40 years old. Although high blood pressure may run in families, many people with a strong family history of high blood pressure never develop it.
What Causes High Blood Pressure?
Most people with high blood pressure have what's called essential or primary hypertension, meaning that the cause is unknown. While research is continuing on this disease, in about 90 percent of patients with high blood pressure, the exact cause is never found. Food containing too much salt may be a factor in causing high blood pressure in certain "salt sensitive" people.
Other forms of high blood pressure are caused by kidney disease, tumors of the adrenal glands near the kidneys, or the narrowing of certain arteries. These problems may be completely correctable. For example, if high blood pressure is caused by a narrowed artery supplying blood to a kidney, repairing this artery will often cure the hypertension without further treatment. Most of these abnormalities can be ruled out by a careful history, a physical examination and a few simple tests. Special tests are occasionally necessary, but it's rarely necessary for someone to be hospitalized for these studies.
How Does High Blood Pressure Develop?
The heart pumps blood through the body's arteries. The large arteries that leave the heart taper down to smaller arteries called arterioles. The arterioles then taper down into smaller vessels called capillaries, which supply the much-needed oxygen and nutrients to the many organs of the body The blood then returns to the heart through the veins.
The small blood vessels in between the arteries and capillaries, the arterioles, are able to dilate (become larger) or contract (become smaller) under the influence of certain nerve impulses. if these vessels are wide open, blood can flow through easily, and no increase in the strength of the heartbeat is necessary to force the blood through. But if these vessels become narrowed, the heart must pump harder to force the blood to flow through these arterioles, and high blood pressure may then occur. When this happens, the heart becomes strained and blood vessels may become damaged. Eventually, changes in the vessels supplying blood to the kidneys and the brain may produce changes in these organs.
Fortunately, the heart, brain and kidneys can withstand increased pressure for long periods of time. That's why many people with high blood pressure may live for years without any symptoms or ill effects. But that doesn't mean it's not hurting them. It's been shown that high blood pressure is one of the most important risk factors for a stroke, heart attack or kidney failure.
What Can Be Done For High Blood Pressure?
How can you help your blood vessels and vital organs withstand the added burden of hypertension? How can your doctor help you? Obviously the strain on your heart can be reduced simply by reducing the demand for blood in various parts of your body. Fatty tissue requires a lot of blood to feed it. Therefore, if you're overweight, one way to reduce the strain on your heart is to lose weight.
In addition to possibly lowering blood pressure and reducing weight, a low-fat, low-cholesterol diet may also help delay the beginning of arteriosclerosis (hardening of the arteries).
Moderate exercise is encouraged to help conditioning, make you feel better, and help to use up calories--but avoid overexertion. If you participate in sports, stop playing when you feel tired. Your doctor should help you plan the exercise program that's best for you.
The excess fluid that sodium (salt) holds in your body may also put an added burden on the heart and "waterlog" the blood vessels, making them contract or narrow more easily. That's why low-sodium diets are also used in treating mild to moderately severe hypertension. in certain instances they're all that's needed to control blood pressure. However, in people with more severe hypertension, salt restriction must be severe (more than just omitting table salt or salt in cooking) if diet alone is to be beneficial. Unfortunately, most people find it hard to continue such restriction for any length of time.
Medications called diuretics, which help to rid your body of excess salt and water, are often prescribed. The sodium content of the diet should, however, be kept at the lowest possible level, even when taking a diuretic. This can be readily accomplished by avoiding salted foods such as peanuts, processed foods, or salt pork, and not adding extra salt to other food. instead of salt, by skillfully using herbs, spices, or salt substitutes(*) you can enhance the flavor of food and allow your taste preferences to gradually shift away from sodium-containing salt.
Increasing the intake of potassium (chart, page 17) or calcium-containing foods may help lower blood pressure in some people. Generally this can't be depended upon as definitive treatment, however.
A person with high blood pressure can usually drink alcohol in moderation, but if you're on a weight-reduction diet, remember that alcohol is high in calories. Some studies suggest that drinking more than 3 to 4 ounces of 80-proof alcohol per day will raise blood pressure. Smoking, another important risk factor of coronary heart disease, should be stopped.
Learning to relax for short periods of time during the working day, at night and on weekends may also be helpful.
(*) Your physician should recommend the type of salt substitute best for you.
What About Drug Treatment?.
In most cases, tranquilizers or sedatives aren't effective in lowering blood pressure significantly
Diuretic agents still remain a cornerstone of most treatment programs, although in some cases another medication may be used as initial treatment. By eliminating excess sodium (salt) and water from the body, these medications help control blood pressure. Some commonly used diuretics are hydrochlorothiazide (Esidrix, Hydro-DIURIL), metolazone (Zaroxolyn, Mykrox), chlorthalidone (Hygroton) and furosemide (Lasix). All these act in a similar manner, although there may be differences in duration of action. Your doctor will probably use the one with which he or she is most familiar.
If diuretic therapy or another medication by itself isn't effective in bringing blood pressure down to normal, your doctor may add other drugs to the treatment program. Often a combination tablet containing a diuretic agent and one of the other specific blood pressure-lowering drugs may be used. This reduces the number of tablets required daily.
The many drugs that may be used are listed in Table 1.
Table 1--Some of the many drugs other than diuretics available for treating high blood pressure.(*)
Nerve Blockers Generic Name Trade Name rauwolfia derivatives Reserpine guanethidine Ismelin guanadrel Hylorel alpha methyldopa Aldomlet clonidine Catapres guanabenz Wytensin prazosin Minipress terazosin Hytrin Beta Blockers propranolol Inderal metoprolol Lopressor nadolol Corgard atenolol Tenormin timolol Blocadren pindolol Visken acebutolol Sectral labetolol Normodyne or Trandate Blood Vessel Dilators hydralazine, Apresoline minoxidil Loniten(**) Hormone inhibitors captopril Capoten enalapril Vasotec lisinopril Prinivel or Zestril Calcium Channel Blockers nifedipine Procardia verapamil Isoptin or Calan diltiazem Cardizem nicardipine Cardene
(*) Many combinations of these drugs are available--usually with a diuretic.
(**) Used in severe cases or when kidney failure is present.
These drugs relax and open up the narrowed blood vessels and lower blood pressure--but only during the time they're working. That's why medication can't be stopped, in most cases, even after blood pressure is lowered. Usually some treatment must be continued--perhaps over a lifetime--to produce continuously good results.
If you're being treated with any of these drugs, the dose of the drug or drugs must be carefully regulated, and you may have to see your doctor often--at least until blood pressure is controlled. After that, visits may be less frequent, perhaps only 3-4 times a year.
You have your own unique medical history, lifestyle and reactions. Your doctor may have to try several drugs before finding the one that's best for you--the one that lowers your blood pressure and gives you the fewest side effects.
What Are Some Side Effects Of Drugs That Lower Blood Pressure?
Certain functions of the body, in addition to those that control blood pressure, can be affected by some of the medications listed above. in other words, there can be some undesirable results (side effects). All medications may produce side effects, but it's important to keep this in perspective. Blood pressure-lowering drugs have proven effective over the years. The benefit derived from their use far outweighs the risk of side effects that may occur in some patients. Most patients who have taken these medications have not experienced any problems. Some side effects that may occur with the above medications, however, are listed below.
1. Diuretic drugs may decrease the body's supply of a mineral called potassium. Symptoms such as weakness, leg cramps or tiredness may result. Foods containing potassium may help prevent significant potassium loss in many patients taking diuretics. (See chart on page 17)
Many doctors prevent loss of potassium by giving a liquid or a tablet containing potassium along with the diuretic, especially in patients receiving digitalis for heart disease. Potassium-saving drugs such as spironolactone (Aldactone), amiloride (Midamar), or triamterene (Dyrenium) might also be prescribed alone but are usually prescribed in combination with another diuretic. Some of these combinations are Dyazide, Moduretic, Maxzide or Aldactazide.
Occasionally some patients suffer from attacks of gout after prolonged treatment with diuretics. This side effect isn't common and can be managed by other treatment.
In patients with diabetes, diuretic drugs may increase the blood sugar level. This can be corrected in most cases by a change in drug dosage, diet, insulin or oral antidiabetic drugs. Your doctor is well aware of these side effects and will adjust your treatment accordingly. In most instances the degree of increase in blood sugar isn't significant. Impotence may also be noted in a small percentage of patients.
2. The beta blockers--propranolol (Inderal), metoprolol (Lopressor), nadolol (Corgard), timolol (Blocadren), atenolol (Tenormin), pindolol (Visken), or acebutolol (Sectral)--may cause insomnia, cold hands and feet, tiredness or depression, a slow heartbeat or may bring on symptoms of asthma. Impotence may occur. Patients with diabetes who are taking insulin should have their responses to therapy monitored carefully
3. Captopril (Capoten), enalapril (Vasotec), or lisinopril (Zestrilor Prinivil) may cause a skin rash; loss of taste; a chronic dry, hacking cough; and in rare instances, kidney damage.
4. Calcium entry blockers--nifedipine (Procardia), diltiazem (Cardizem), verapamil (Isoptin or Calan), and nicardipine (Cardene)--may cause palpitations, ankle swelling, constipation, headache or dizziness. Side effects with each of these medications differ a great deal.
5. Alpha methyidopa (Aldomet) may produce a greater drop in blood pressure when you're in an upright position (standing or walking) and may cause a feeling of weakness or faintness if the pressure has been lowered too far. This drug may also cause drowsiness or "sluggishness," dryness of the mouth, fever or anemia. Male patients taking the drug may experience impotence, which may be quite annoying. If this symptom persists, your doctor may have to change the drug dosage or use another medication.
6. Clonidine (Catapres) or guanabenz (Wytensin) may produce severe dryness' of the mouth, constipation or drowsiness. If you're taking either of these drugs, never stop doing so suddenly, because blood pressure may rise quickly to high levels.
7. Prazosin (Minipress) may cause fatigue or dizziness.
8. Rauwolfia drugs (Reserpine) may cause a stuffy nose, occasional diarrhea or heartburn. These effects aren't severe and no treatment is required other than a change in the amount of medication taken. If nightmares, insomnia or depression occur, tell your doctor because the drug should be discontinued.
9. Hydralzine (Apresoline) may cause headaches, swelling around the eyes, heart palpitations or aches and pains in the joints. Usually none of these symptoms a severe, and most will disappear after several weeks of treatment. This medication isn't usually used by itself.
10. Guanethidine (ismelin) or guanadrel (Hylorel) may cause some diarrhea. This may persist in some people. Generally this side effect becomes less troublesome with continued treatment.
Because these drugs reduce blood pressure to a greater degree when a person is standing, a user may experience occasional dizziness, lightheadedness, and feelings of weakness when getting out of bed in the morning or standing up suddenly. If you note any of these reactions, and if they persist for longer than a minute or two, it's important to sit or even lie down and either reduce or omit the next dose of the drug. If symptoms continue, contact your doctor.
When you're taking guanethidine, don't remain standing in the hot sun or at a cocktail party if you begin to feel faint or weak. These activities cause low blood pressure. Male patients may experience a form of impotence that isn't harmful, but which can be annoying. Contact your doctor if this occurs. These drugs are rarely used unless other medications prove ineffective.
11. Minoxidil (Loniten) is a potent drug that's usually used only in resistant cases of severe high blood pressure. It may cause retention of fluid (marked weight gain) or excessive hair growth. This can be annoying for female patients.
If you know beforehand how these drugs may affect you--and know what to do about their side effects--it will be easier for you to continue treatment. Your patience will usually be rewarded by good long-term results: lower blood pressure and a longer life.
Foods To Remember
The following lists will give you an idea of which foods to eat or stay away from to keep your potassium intake high and' your salt or sodium intake low.
Certain salt substitutes contain a large amount of potassium and very little sodium. These are inexpensive and may be used freely by most people, except those who have kidney disease. Check with your doctor before choosing a salt substitute.
Good: These foods are relatively high in potassium and low in sodium. Extra amounts of these foods may help prevent a potassium deficiency.
Fruits Apple (*)Nectarine Apricot Prune (*)Avocado (*)Raisin (*)Banana Watermelon (*)Cantaloupe Apple Juice Date (*)Grapefruit Juice Grapefruit Prune Juice (*)Honeydew Melon Orange Juice Vegetables Asparagus Peas, Green (fresh Beans, White or Green and cooked) Broccoli Peppers Brussels Sprouts (*)Potatoes (baked or Cabbage (cooked) boiled) Cauliflower (cooked) Squash, Summer and Corn-on-the-cob Winter (cooked) Eggplant (cooked) Lima Beans (fresh and cooked) (*) especially helpful.
Avoid: These foods are relatively high in potassium and also high in sodium or salt. Limit or avoid them:
Canned Tomato Juice Frozen Peas Raw Clams Canned Spinach Sardines Canned Carrots Frozen Lima Beans
Some Final Advice
Modern treatment of high blood pressure is generally quite simple in most people. It may, however, be complicated in some cases and require a great deal of time, patience, and care by both doctor and patient. It may be annoying to take pills and possibly experience side effects when you may have felt fine before treatment.
Don't be discouraged if you must continue treatment indefinitely. Some patients are able to reduce the dosages of drugs after normal blood pressure has been achieved and maintained for a year or more. (Treatment can rarely be discontinued.) The treatment is far less than is required to treat the complications of high blood pressure. Most cases respond to treatment, and most patients whose blood pressure has been successfully treated live a long and normal life.
Not everyone with high blood pressure needs to be treated with drugs listed in this booklet. Some people may do just as well on other therapy. You should not insist that your physician use a certain medication because you've read or heard about its wonderful effect on other people. You could have a serious side effect from taking a "wonder drug" that wasn't appropriate for you in the first place. Let your doctor decide what drug, if any, to use.
There are many drugs now being studied that may prove useful in the future.
Learning To Live With High Blood Pressure. Remember:
* Don't be frightened by high blood pressure. It can be treated effectively.
* Do the simple things that your doctor suggests. Simple measures, such as reducing weight or cutting back on salt, may produce good results.
* Don't rush frantically from one doctor to the next, looking for a quick, easy "miracle drug." Stick to one reliable doctor or one good clinic and follow through with the treatment plan.
* If you do find yourself on drug therapy, be patient and don't stop treatment if side effects occur. Do let your doctor know about any side effects.
* Give yourself a chance to adjust to a drug's reaction if one occurs. It often takes several weeks to do so, but the results will usually justify your persistence.
* Death rates from strokes have decreased dramatically in the past 15 years.
* Death rates from cardiovascular and kidney diseases have decreased significantly
* A large part of this improvement is probably the result of earlier and better treatment of high blood pressure.
This material is made available as part of the public education program of the American Heart Association and no endorsement of any product or service should be inferred or is intended if distributed by other agencies or concerns.