Introduction to Hypertension
Hypertension or high blood pressure is a condition in which a person's blood pressure is raised. Blood pressure is the measure of the force of the blood flow in the arterial blood vessels that carry blood from the heart to the rest of the body. Hypertension results from two major factors, which can be present independently or together, (a) the heart pumps blood with excessive force, (b) the body's smaller blood vessels (known as the arterioles) narrow, so that blood flow exerts more pressure against the vessels' walls.
Hypertensive patients are at increased risk of the following:
> Heart failure
> Stroke i.e. blood clot in brain
> Hardened arteries (atherosclerosis)
> Aortic aneurysm often resulting in sudden cardiac death
> Kidney failure
> Retinopathy (loss of vision)
Are you at risk?
From your daily routine and habits to your health status and genetic heritage, many factors can raise your blood pressure. Understand what your risk factors are so that you can help prevent or delay the onset of high blood pressure and its life- threatening complications.
Some of the lifestyle factors that can contribute to high blood pressure include excess weight, lack of exercise, unhealthy diet, stress, and tobacco products. The good news is that by making even small changes to your lifestyle, you can reap big rewards for your health.
Certain medical conditions can cause high blood pressure. This type of high blood pressure is called secondary hypertension. Some of the numerous conditions that can cause secondary hypertension include polycystic kidney disease, cushing's disease, and coarctation of the aorta. By effectively treating these medical conditions, you can typically get your blood pressure under control or even cure it.
Certain prescription medications, over-the-counter drugs, supplements and other substances can induce or worsen high blood pressure or interfere with the action of medications you're taking to lower your blood pressure. Among these numerous substances are, certain antidepressants, certain cold medicines, certain oral contraceptives, and illicit drugs like cocaine. One obvious solution is to avoid illicit drugs, as well as unnecessary medications. In addition, talk to your doctor about medications or other substances that could affect your blood pressure.
Unfortunately, you can't control all of the factors that may increase your risk of high blood pressure. Two major risk factors for high blood pressure that you can't control are, being older than 55 and having a family history of high blood pressure. If you have any uncontrollable risk factors, don't simply assume you'll get high blood pressure eventually, no matter what efforts you make. That's not true. You may be able to compensate by changing the risk factors you can control.
Two numbers are used to describe blood pressure:
Systolic: The systolic pressure (the higher and first number) measures the force that blood exerts on the artery walls as the heart contracts to pump out the blood.
Diastolic: The diastolic pressure (the lower and second number) is the measurement of force as the heart relaxes to allow the blood to flow into the heart.
Normal blood pressure for adults is considered to be under 120/80 millimeters of mercury. Generally, blood pressure above 140/90 is considered to be high for adults, and blood pressure under 90/60 is considered to be low for adults.
Pre-hypertension, is used when individuals with blood pressures between 120-139/80-89 who do not take anti-hypertension drugs. Such individuals do not require any medication, but they need to adopt certain lifestyles which are known reduce blood pressure. It includes weight loss, diet, exercise, reducing salt intake and quitting smoking.
The risk of developing one or more of these serious health conditions increases as blood pressure rises. The following categories apply to adults (age 18 and over) who are not taking medicine for high blood pressure and do not have a serious short-term illness:
Optimal: Systolic (Under 120) AND Diastolic (under 80)
Pre-hypertensive: Systolic (120-139) OR Diastolic (80-89)
Stage 1: Systolic (140-159) OR Diastolic (90-99)
Stage 2: Systolic (160-179) OR Diastolic (100-109)
Stage 3: Systolic (180-209) OR Diastolic (100-119)
Stage 4: Systolic (210 or over) OR Diastolic (120 or over)
Signs and Symptoms
The majority of people with mild to moderate high blood pressure cannot tell when their blood pressure is raised. One-third of hypertensive people are not aware of their condition. If symptoms are present, patients may experience chest pain (angina), shortness of breath or other symptoms related to heart disease or underlying damage. High blood pressure may cause any of the following: fatigue, nausea or upset stomach, vision changes or problems, confusion, excessive sweating, paleness or redness of skin, nosebleeds, anxiety or nervousness, palpitations (fast or obviously irregular heartbeat), ringing or buzzing in ears, impotence, headache, dizziness.
Depending on the severity of high blood pressure, the physician may recommend lifestyle modifications, or lifestyle modifications in conjunction with medications. Steps that can and should be taken to lower and control blood pressure include:
Dietary Changes: Avoid saturated fat (although include calcium-rich dairy products that are no- or low-fat). When choosing fats, select monounsaturated oils, such as olive or canola oils. Choose whole grains over white flour or polished rice products. Food rich in fiber may help lower blood pressure. Include nuts, seeds, or legumes (dried beans or peas) daily. Choose modest amounts of protein (preferably fish, poultry, or soy products).
Salt restriction: About half of people with hypertension have blood pressure that reacts significantly to salt. Such people are known to be salt-sensitive. High-salt diets in anyone who is salt-sensitive may harm the heart, kidney, and brain and increase the risk for death, regardless of their blood pressure. Because testing for salt-sensitivity is not easy, experts recommend that everyone proactively restrict their daily salt-intake.
Quitting smoking: This is perhaps the most important thing a smoker can do to promote his or her own health. Among many other side effects, smoking elevates blood pressure.
Losing weight: Loss of weight in the abdominal area can immediately reduce blood pressure and help reduce the size of the heart. Weight loss accompanied by salt restriction may allow mild hypertensives to reduce or eliminate their need for medication.
Add dietary supplements: Antioxidants, such as vitamin C and vitamin E, help the body eliminate oxidants, or oxygen free radicals, which are damaging particles produced as part of the body's chemical processes. Also, adequate intake of minerals such as potassium, magnesium and calcium is thought by some experts to be even more helpful than reducing salt intake for reducing blood pressure. Omega 3 Fatty Acids appear to help keep blood vessels flexible and may also help protect the nervous system. Individuals should consult with their physician before supplementing their diet.
Regular exercise: Exercising at least three to four times per week is helpful for regulating high blood pressure, keeping in mind that the regularity of the exercise is more important than the intensity of the workout. Regular exercise helps keep arteries elastic, even an in older person, which in turn ensures blood flow and normal blood pressure. Sedentary people have a 35% greater risk of developing hypertension than athletes do.
Stress management: Emotional factors may play important roles in the development of hypertension. Studies suggest that stress reduction programs, can reduce blood pressure. In some cases people can even go off medication. Even pets can provide healthful support.
Good sleep habits: Insufficient sleep may raise blood pressure in patients with hypertension, placing them at increased risk of cardiovascular morbidity and mortality. Stress hormone levels increase with sleeplessness, which can activate the sympathetic nervous system, a strong player in hypertension. Patients who have chronic insomnia or other severe sleep disturbances should consider consulting sleep experts if life style measures are not helpful.
Care while taking drugs: Hypertensives must also be careful about using certain over-the-counter (OTC) medications that contain vasoconstrictors, which can elevate blood pressure. Such medications include eye drops, antihistamines, cold, flu, and sinus and cough medications (especially those containing decongestants).
Women are also encouraged to discuss with their physicians the increased risk of high blood pressure that results from taking birth control pills, particularly if they are over the age of 35. High blood pressure is two to three times more common in women taking birth control pills than those not taking them, especially in women who are overweight.
Other lifestyle considerations: People with high blood pressure should avoid certain activities and situations that may raise their heart rates and blood pressure to dangerous levels. These include activities such as saunas, steam rooms and very warmly heated swimming pools.
Blood pressure reducing medications: In addition to these lifestyle changes, patients are often prescribed blood pressure-reducing medications. These medications include: Diuretics, Alpha blockers, beta blockers, alpha and beta blockers, ACE inhibitors, Angiotensin II receptor blockers (ARBs), calcium channel blockers,central agonists, nervous system inhibitors such as peripheral adrenergic inhibitors and blood vessel dilators.
How do drugs work?
Diuretics are sometimes called "water pills" because they work in the kidney and flush excess water and sodium from the body.
Beta-blockers reduce nerve impulses to the heart and blood vessels. This makes the heart beat slower and with less force. Blood pressure drops and the heart works less hard.
Angiotensin converting enzyme (ACE) inhibitors prevent the formation of a hormone called angiotensin II, which normally causes blood vessels to narrow. The ACE inhibitors cause the vessels to relax and blood pressure goes down.
Angiotensin antagonists shield blood vessels from angiotensin II. As a result, the vessels become wider and blood pressure goes down.
Calcium Channel Blockers keep calcium from entering the muscle cells of the heart and blood vessels. This causes the blood vessels to relax and pressure goes down.
Alpha-blockers reduce nerve impulses to blood vessels, which allows blood to pass more easily, causing the blood pressure to go down.
Alpha-beta-blockers work the same way as alpha-blockers but also slow the heartbeat, as beta-blockers do. As a result, less blood is pumped through the vessels and the blood pressure goes down.
Nervous system inhibitors relax blood vessels by controlling nerve impulses. This causes the blood vessels to become wider and the blood pressure to go down.
Side effect of drugs
Some of the drugs listed below can affect certain functions of the body, resulting in bad side effects. However, drugs that lower blood pressure have proven effective over the years. The benefits of using them far outweigh the risk of side effects. Most people who have taken these drugs haven't had any problems.
Diuretics: Some of these drugs may decrease your body's supply of a mineral called potassium. Symptoms such as weakness, leg cramps or being tired may result. Eating foods containing potassium may help prevent significant potassium loss. You can prevent potassium loss by taking a liquid or tablet that has potassium along with the diuretic, if your doctor recommends it. Diuretics such as amiloride, spironolactone or triamterene are called "potassium sparing" agents. They don't cause the body to lose potassium. They might be prescribed alone but are usually used with another diuretic.
Some people suffer from attacks of gout after prolonged treatment with diuretics. This side effect isn't common and can be managed by other treatment. In people with diabetes, diuretic drugs may increase the blood sugar level. A change in drug, diet, insulin or oral antidiabetic dosage corrects this in most cases. Your doctor can change your treatment. Most of the time the degree of increase in blood sugar isn't much. Impotence may also occur in a small percentage of people.
Beta-blockers: These drugs, such as acebutolol, atenolol, metoprolol, nadolol, pindolol, propranolol or timolol, may cause insomnia, cold hands and feet, tiredness or depression, a slow heartbeat or symptoms of asthma. Impotence may occur. If you have diabetes and you're taking insulin, have your responses to therapy monitored closely.
ACE inhibitors: These drugs, such as captopril, enalapril, lisinopril, may cause a skin rash; loss of taste; a chronic dry, hacking cough; and in rare instances, kidney damage.
Angiotensin II receptor blockers: These drugs may cause occasional dizziness.
Calcium channel blockers: These drugs, such as diltiazem, nicardipine, Nifedipine and verapamil, may cause palpitations, swollen ankles, constipation, headache or dizziness. Side effects with each of these drugs differ a great deal.
Alpha blockers: These drugs may cause fast heart rate, dizziness or a drop in blood pressure when you stand up.
Combined alpha and beta blockers: People taking these drugs may experience a drop in blood pressure when they stand up.
Central agonists: Alpha methyldopa may produce a greater drop in blood pressure when you're in an upright position (standing or walking) and may make you feel weak or faint 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 may experience impotence. If this side effect persists, your doctor may have to change the drug dosage or use another medication.
Clonidine, guanabenz or guanfacine may produce severe dryness of the mouth, constipation or drowsiness. If you're taking any of these drugs, don't stop suddenly, because your blood pressure may rise quickly to dangerously high levels.
Peripheral adrenergic inhibitors: Reserpine may cause a stuffy nose, diarrhea or heartburn. These effects aren't severe and no treatment is required other than to change the amount of drugs taken. If you have nightmares or insomnia or get depressed, tell your doctor. You should stop using the drugs.
Guanadrel or guanethidine may cause some diarrhea, which may persist in some people. This side effect usually becomes less of a problem if you continue treatment. These drugs reduce blood pressure more when you stand. Consequently, you may get dizzy and lightheaded and feel weak when you get out of bed in the morning or stand up suddenly. If you notice any of these reactions and if they persist for more than a minute or two, sit or 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 keep standing in the hot sun or at a social gathering if you begin to feel faint or weak. These activities cause low blood pressure. Male patients may experience impotence. Contact your doctor if this occurs. These drugs are rarely used unless other medications don't help.
Blood vessel dilators: Hydrazine may cause headaches, swelling around the eyes, heart palpitations or aches and pains in the joints. Usually none of these symptoms are severe, and most will go away after a few weeks of treatment. This drug isn't usually used by itself. Minoxidil is a potent drug that's usually used only in resistant cases of severe high blood pressure. It may cause fluid retention (marked weight gain) or excessive hair growth.