High Blood Pressure (Hypertension)

When you have high blood pressure, or hypertension, the force of blood against your artery walls is too strong. High blood pressure can damage your arteries, heart, and kidneys, and lead to atherosclerosis and stroke. Hypertension is called a "silent killer" because it does not cause symptoms unless it is severely high and, without your knowing it, causes major organ damage if not treated.

Your blood pressure measurement consists of two numbers, systolic and diastolic. The systolic measurement is the pressure of blood against your artery walls when the heart has just finished pumping (contracting). It is the first or top number of a blood pressure reading. The diastolic measurement is the pressure of blood against your artery walls between heartbeats, when the heart is relaxed and filling with blood. It is the second or bottom number in a blood pressure reading. You are considered to have high blood pressure if your systolic measurement is 140 or above and your diastolic measurement is 90 or above.

In most cases, a doctor may not be able to pinpoint the exact cause of your high blood pressure. But, several factors are known to increase blood pressure, including obesity, heavy alcohol use, family history of high blood pressure, high salt intake, and aging. A sedentary lifestyle, stress, low potassium intake, low calcium intake, and resistance to insulin may also cause your blood pressure to rise. If one or more of these factors is causing your high blood pressure, you have primary, or essential, high blood pressure, which is the most common type. Secondary high blood pressure is caused by certain medications or other conditions, such as pregnancy or narrowing of the kidney arteries.

Several factors increase your risk for developing high blood pressure. Some of them, such as salt intake and alcohol consumption, are lifestyle issues that you can control. Other factors, such as your family history, are not controllable. Risk factors for primary (essential) high blood pressure include:

  • A family history of high blood pressure.
  • Aging. Ninety percent of people who, at age 55, do not have hypertension will eventually develop it.
  • Black race.
  • Sodium (salt) intake.
  • Excessive alcohol consumption.
  • Low intake of potassium, magnesium, and calcium.
  • Obesity.

Usually you will not feel any warning signs or symptoms of high blood pressure and you will not know you have it until a health professional takes a blood pressure reading. Hypertension develops slowly and can cause serious organ damage, usually without any symptoms. If you develop very severe high blood pressure, you may have headaches, visual disturbances, nausea, and vomiting. Over time, if you do not receive treatment for your high blood pressure, you may feel symptoms caused by damage to your heart, kidneys, or eyes, including:

  • Coronary artery disease, heart attack, heart failure, or abnormal heart beat.
  • Kidney (renal failure).
  • Peripheral vascular disease.
  • Retinopathy, or damage to the tiny blood vessels that supply blood to the light-sensitive lining of the back of the eye (retina).
  • Stroke.

You will be diagnosed with hypertension if your blood pressure measurements are high (above 140/90 mm Hg) on three or more separate occasions. They are usually measured 1 to 2 weeks apart. Except in very severe cases, the diagnosis is not based on a single measurement.

If you fall into the pre-hypertension range (120-139/80-89 mm Hg), your doctor will likely recommend lifestyle modifications, including losing excess weight, exercising, limiting alcohol, cutting back on salt, quitting smoking, and following the Dietary Approaches to Stop Hypertension (DASH) diet. The DASH eating plan is a low-fat and low-saturated-fat diet that emphasizes eating more fruits, vegetables, whole grains, and low-fat dairy foods. If you have high blood pressure (140-159/90-99 mm Hg) and you do not have any organ damage or other risk factors for heart disease (uncomplicated high blood pressure), your doctor will likely recommend lifestyle changes and possibly medications. Most people with high blood pressure will need two or more medications, including a thiazide-type diuretic, to lower their blood pressure to below 140/90 mm Hg, the goal for people with uncomplicated hypertension. If you have other conditions, such as diabetes, heart failure, or chronic kidney disease, your goal blood pressure is lower: 130/80 mm Hg. If your blood pressure is 160-179/100-109 mm Hg or higher, you and your doctor may need to try various combinations of medications to find what works best for you. You will also need to make aggressive lifestyle changes. Overall, your treatment will depend on how high your blood pressure is, whether you have other medical conditions, such as diabetes, and whether any organs have already been damaged. Your risk of developing other diseases, especially heart disease, will be another important factor your doctor will consider.

Although you may have your blood pressure checked outside of a doctor's office, you must see a health professional to confirm that you have high blood pressure, so that you and your doctor can develop a treatment plan that's right for you. A family practice doctor, internist, nurse practitioner, or physician's assistant can diagnose and treat your high blood pressure. If you have extremely high blood pressure or heart problems, you may also need to see a heart specialist (cardiologist).

If you have primary (essential) hypertension, you will first need to look closely at the foods you eat. Your health professional may recommend that you follow the DASH diet. Losing weight if you need to and exercising will also be important for lowering your blood pressure. If you smoke cigarettes, you will need to quit. If you are a heavy drinker, you will need to severely cut back on your consumption of alcohol. Also, it may be necessary for you to learn to check your blood pressure at home. High blood pressure treatment, whether it involves medication or lifestyle changes, usually is a lifelong process. Whether you need medication depends on the severity of your high blood pressure and whether you have other health problems or conditions, such as heart failure or diabetes, or are pregnant. If your doctor prescribes medication, it is extremely important to take your medications as prescribed.

Call a doctor immediately if you have high blood pressure and:

  • Your blood pressure is usually normal or well controlled, but it suddenly goes well above the normal range on more than one occasion.
  • Your blood pressure is 180/110 mm Hg or higher.
  • A sudden, severe headache.
  • Chest pain (angina).
  • Other symptoms of a heart attack.
  • Symptoms of a stroke or transient ischemic attack.

Call a doctor if:

  • Your blood pressure is 140/90 mm Hg or higher on two or more occasions (taken at home or in a community screening program). If one blood pressure measurement is high, have another reading taken by a health professional to verify the first reading.
  • You develop significant side effects from any medication you take for high blood pressure.

Adults are encouraged to have their blood pressure checked regularly.

Your blood pressure can be checked:

  • At a clinic where you work or go to school.
  • At health fairs, fitness centers, community centers, fire stations, and ambulance stations.
  • By a nurse practitioner or physician's assistant.
  • By a primary care doctor.