Hypertension : High Blood Pressure

In 90% of people with hypertension, the cause of high blood pressure is not known and is referred to as primary or essential hypertension.
While the specific cause is unknown, there are two kinds of risk factors that can contribute to developing high blood pressure.

1. Factors that can not be changed
    Age: The older a person is, the greater the likelihood that he or she will develop high blood pressure, especially elevated systolic readings. This is largely due to arteriosclerosis, or "hardening of the arteries."
    Race: African Americans develop high blood pressure more often than Caucasians. They develop high blood pressure at a younger age and develop more severe complications sooner in life.
    Socioeconomic status: High blood pressure is found more commonly among the less educated and lower socioeconomic groups. Residents of the southeastern United States, both Caucasian and African American, are more likely to have high blood pressure than residents of other regions.
    Family history (heredity): The tendency to have high blood pressure appears to run in families.
    Gender: Generally men have a greater likelihood of developing high blood pressure than women. This likelihood varies according to age and among various ethnic groups.

2. Factors that can be changed
  • Blood pressure.
  • Lifestyle
  • Obesity: As body weight increases, the blood pressure rises. Obesity is defined as having a body mass index (BMI) greater than 30 kg/m . A BMI of 25-30 kg/m  is considered overweight (BMI=weight in pounds x 703/ height in inches  ) Being overweight increases the risk of high blood pressure. Health care practitioners recommend that all obese people with high blood pressure lose weight until they are within 15% of their healthy body weight.
  • Obese people are two to six times more likely to develop high blood pressure than people whose weight is within a healthy range.
  • Not only the degree of obesity is important, but also the manner in which the body accumulates extra fat. Some people gain weight around their belly (central obesity or "apple-shaped" people), while others store fat around their hips and thighs ("pear-shaped" people). "Apple-shaped" people tend to have greater health risks for high blood pressure than "pear-shaped" people.
  • Sodium (salt) sensitivity: Some people have high sensitivity to sodium (salt), and their blood pressure increases if they use salt. Reducing sodium intake tends to lower their blood pressure. Americans consume 10-15 times more sodium than they need. Fast foods and processed foods contain particularly high amounts of sodium. Many over-the-counter medicines also contain large amounts of sodium. Read food labels and learn about salt content in foods and other products as a healthy first step to reducing salt intake. Fast food restaurants also make the salt and calorie content of their food available to consumers at their restaurants,
  • Alcohol use: Drinking more than one to two drinks of alcohol per day tends to raise blood pressure in those who are sensitive to alcohol.
  • Birth control pills (oral contraceptive use): Some women who take birth control pills develop
  • ck of exercise (physical inactivity): A sedentary lifestyle contributes to the development of obesity and high blood pressure.
  • Medications: Certain drugs, such as amphetamines (stimulants), diet pills, and some medications used for cold and allergy symptoms such as pseudoephedrine, tend to raise blood pressure.

High Blood Pressure Symptoms

High blood pressure usually causes no symptoms and high blood pressure often is labeled "the silent killer." People who have high blood pressure typically don't know it until their blood pressure is measured.
Sometimes people with markedly elevated blood pressure may develop:
headache, dizziness, blurred vision, nausea and vomiting, chest pain and shortness of breath.
People ussually do not seek medical care until they have symptoms arising from the organ damage caused by chronic (ongoing, long-term) high blood pressure.

The following types of organ damage are commonly seen in chronic high blood pressure :
  •     Heart attack
  •     Heart failure
  •     Stroke or transient ischemic attack (TIA)
  •     Kidney failure
  •     Eye damage with progressive vision loss
  •     Peripheral arterial disease causing leg pain with walking (claudication)
  •     Outpouchings of the aorta, called aneurysms
About 1% of people with high blood pressure do not seek medical care until the high blood pressure is very severe, a condition known as malignant hypertension.
In malignant hypertension, the diastolic blood pressure (the lower number) often exceeds 140 mm Hg.
    Malignant hypertension may be associated with headache, lightheadedness, nausea, vomiting, and stroke like symptoms
    Malignant hypertension requires emergency intervention and lowering of blood pressure to prevent brain hemorrhage or stroke.
    It is of utmost importance to realize that high blood pressure can be unrecognized for years, causing no symptoms but causing progressive damage to the heart, other organs, and blood vessels.

High Blood Pressure Diagnosis

    Blood pressure is measured with a blood pressure cuff (sphygmomanometer).
This may be done using a stethoscope and a cuff and gauge or by an automatic machine. It is a routine part of the physical examination and one of the vital signs often recorded for a patient visit. Other vital signs include pulse rate, respiratory rate (breathing rate), temperature, and weight.
    When discussing blood pressure issues, the health care practitioner may ask questions about past medical history, family history, and medication use, including prescriptions, over-the-counter medications, herbal remedies, and food additives. Other questions may include lifestyle habits, including activity levels, smoking, alcohol consumption, and illegal drug use.
    Physical examination may include listening to the heart and lungs, feeling for pulse in the wrist and ankles, and feeling and listening to the abdomen looking for signs of an enlarged aorta. Eye examination with an ophthalmoscope may be helpful by looking at the small blood vessels on the retina in the back of the eyeball.  

Human Blood Pressure

  • Normal Blood Pressure : Systolic less than 120 mm Hg; diastolic less than 80 mm Hg
  • Prehypertension : Systolic 120-139 or diastolic 80-89 mm Hg
  • High Blood Pressure :
  • Stage 1: Systolic 140-159; diastolic 90-99 mm Hg
  • Stage 2: Systolic more than 160; diastolic more than 100 mm Hg
Blood tests may be considered to assess risk factors for heart disease and stroke as well as looking for complications of hypertension.
These include complete blood count (CBC), electrolytes, BUN (blood urea nitrogen), and creatinine and GFR (glomerular filtration rate) to measure kidney function.
A fasting lipid profile will measure cholesterol and triglyceride levels in the blood. If appropriate, blood tests may be considered to look for an underlying cause of high blood pressure including abnormal thyroid or adrenal gland function.
  • Electrocardiogram (ECG) may help evaluate heart rate and rhythm. It is a screening test to help assess heart muscle thickness. If hypertension is long-standing, the heart muscle has to hypertrophy, or get larger, to push blood against the increased pressure within the arteries of the body.
  • Echocardiogram is an ultrasound examination of the heart It is used to evaluate the anatomy and the function of the heart. A cardiologist is required to interpret this test and can evaluate the heart muscle and determine how thick it is, whether it moves appropriately, and how efficiently it can push blood out to the rest of the body. The echocardiogram can also assess heart valves, looking for narrowing (stenosis) and leaking (insufficiency or regurgitation). A chest X-ray may be used as a screening test to look for heart size, the shape of the aorta, and to assess the lungs.
  • Doppler ultrasound is used to check blood flow through arteries at pulse points in your arms, legs, hands, and feet. This is an accurate way to detect peripheral vascular disease, which can be associated with high blood pressure. It also can measure blood flow in the arteries to both kidneys and sometimes depicts narrowings that can lead to high blood pressure in a minority of patients.

High Blood Pressure Treatment

Blood pressure control is a lifelong challenge. Hypertension can progress through the years, and treatments that worked earlier in life may need to be adjusted over time.
Blood pressure control may involve a stepwise approach beginning with diet, weight loss, and lifestyle changes and eventually adding medications as required.
In some situations, medications may be recommended immediately. As with many diseases, the health care practitioner and patient work together as a team to find the treatment plan that will work for that specific individual.

Self-Care at Home

The management and control of high blood pressure involves two major options, lifestyle modification and medication.
  • Lifestyle Modifications to Manage High Blood Pressure
  • Weight Control
  • Aim for a healthy weight range for your height and body type. Your health care practitioner can help you calculate a healthy target weight. Even a small amount of weight loss can make a major difference in lowering or preventing high blood pressure.
  • You must burn more calories than you take in to lose weight.
  • Crash or fad diets are not helpful and may be dangerous.
  • Some weight loss medications also carry major risks and may even elevate blood pressure, and great caution is advised in using these drugs. Please ask your health care practitioner or pharmacist for help in deciding if a weight loss medication is appropriate for your situation.
  • Exercise or Increase Physical Activity
  • Physical activity reduces total cholesterol and bad cholesterol (low density lipoprotein or LDL) and raises the good cholesterol (high density lipoprotein or HDL).
  • Both the American Heart Association (AHA) and the U.S. Surgeon General recommend 30 minutes of physical activity on most days of the week.
  • Physical activity includes many daily activities such as cleaning the house, raking the lawn, and walking. Other possible sources of activity can include using the stairs instead of an elevator or escalator, walking for errands instead of driving a car, and participating in a sport or social activity such dancing.

High Blood Pressure Medications

It may take trial and error to find the proper medication or combination of medications that will help control hypertension in each case. It is important to take the medications as prescribed and only discontinue them on the advice of your health care practitioner.

Water Pills (diuretics)

    Diuretics are used very widely to control mildly high blood pressure, and are often used in combination with other medications. They increase sodium excretion and urine output and decrease blood volume. The sensitivity to the effect of other hormones in your body is decreased.
    One example of a diuretic is hydrochlorothiazide
The most commonly used diuretics to treat hypertension include:
  • hydrochlorothiazide (HydroDIURIL),
  • the loop diuretics furosemide (Lasix) and torsemide (Demadex),
  • the combination of triamterene and hydrochlorothiazide (Dyazide), and metolazone (Zaroxolyn).

    Beta-blockers reduce heart rate and decrease the force of heart contraction by blocking the action of adrenaline receptors. Beta blockers are widely prescribed and effective but can cause increased fatigue and decreased exercise tolerance because they prevent an increased heart rate as a normal response to physical activity. Beta-Blockers also prescribed for people who have associated heart disease, angina, or history of a heart attack.
    Examples of beta blockers include: carvedilol (Coreg), metoprolol (Lopressor), atenolol (Tenormin)

Calcium Channel Blockers (CCBs)
    Calcium channel blocking agents work by relaxing the muscle in artery walls and by therefore reducing the force of contraction of heart muscle.
    Example of calcium channel blockers include, nifedipine (Procardia), diltiazem (Cardizem), verapamil (Isoptin, Calan), nicardipine (Cardene), amlodipine (Norvasc), and felodipine (Plendil)

Angiotensin-Converting Enzyme (ACE) Inhibitors
    ACE inhibitors stop the production in the body of a chemical called angiotensin II, which causes blood vessels to contract. Narrower blood vessels are associated with increased blood pressure. Relaxing artery walls leads to lower blood pressure.
    Examples of ACE inhibitors include Captopril (Capoten), enalapril (Vasotec), lisinopril (Zestril, Prinivil), quinapril (Accupril), and fosinopril (Monopril)

Angiotensin Receptor Blockers (ARBs)
    ARBs work block angiotensin II receptors and prevent vasoconstriction, or narrowing of blood vessels.
    Examples of ARBs include losartan (Cozaar), valsartan (Diovan), candesartan (Atacand), and irbesartan (Avapro)

Blockers of Central Sympathetic (autonomic nervous) System   
      These agents block messages from the brain's autonomic nervous system that contract blood vessels. The autonomic nervous system is the part of the unconscious nervous system of the body that controls heart rate, breathing rate, and other basic functions. These medications relax blood vessels, thus lowering blood pressure.
    An example is clonidine (Catapres)

Direct Vasodilators
    Direct vasodilators relax (dilate) the blood vessels to allow blood to flow under lower pressure.
    These medications are most often used in times of hypertensive crisis and are injected intravenously to quickly lower blood pressure readings.
    Examples include nitroprusside (Nitropress), and diazoxide (Hyperstat).

Other Therapy

Alternative therapies may be helpful to people trying to control their blood pressure.
    Acupuncture and biofeedback are well-accepted alternative techniques that may help some people with high blood pressure.
    Techniques that induce relaxation and reduce stress are recommended. These include meditation, yoga, and relaxation training.
    These techniques alone may not control high blood pressure for many people. They should not be used as a substitute for medical therapy without first consulting with your health care practitioner.
Dietary supplements and alternative medications and therapies are sometimes recommended for high blood pressure.
    Examples include vitamins, garlic, fish oil, L-arginine, soy, coenzyme Q10, herbs, phytosterols, and chelation therapy.
    While these substances may be beneficial, the exact nature of their benefits is not known.
    Scientific studies have produced no evidence that these therapies lower blood pressure or prevent the complications of high blood pressure.
    Most of these substances are harmless if taken in moderate doses. Most people can take them without problems.
    Talk to your health care practitioner if you are considering any of these treatments. Substituting these therapies for medical therapies that have been shown to lower blood pressure and the risk of complications may have a harmful effect on your health.