Hypertension is the term used to describe high blood pressure.
Blood pressure is a measurement of the force against the walls of your arteries as the heart pumps blood through the body.
Blood pressure readings are measured in millimeters of mercury (mmHg) and usually given as two numbers -- for example, 120 over 80 (written as 120/80 mmHg). One or both of these numbers can be too high.
The top number is your systolic pressure.
- It is considered high if it is over 140 most of the time.
- It is considered normal if it is below 120 most of the time.
The bottom number is your diastolic pressure.
- It is considered high if it is over 90 most of the time.
- It is considered normal if it is below 80 most of the time.
Pre-hypertension may be considered when your:
- Top number (systolic blood pressure) is between 120 and 139 most of the time, or
- Bottom number (diastolic blood pressure) is between 80 and 89 most of the time
If you have pre-hypertension, you are more likely to develop high blood pressure.
If you have heart or kidney problems, or if you had a stroke, your doctor may want your blood pressure to be even lower than that of people who do not have these conditions.
See also: Blood pressure
High blood pressure; HBP; Blood pressure - high
Causes, incidence, and risk factors
Many factors can affect blood pressure, including:
- How much water and salt you have in your body
- The condition of your kidneys, nervous system, or blood vessels
- The levels of different body hormones
You are more likely to be told your blood pressure is too high as you get older. This is because your blood vessels become stiffer as you age. When that happens, your blood pressure goes up. High blood pressure increases your chance of having a stroke, heart attack, heart failure, kidney disease, and early death.
You have a higher risk of high blood pressure if you:
- Are African American
- Are obese
- Are often stressed or anxious
- Eat too much salt in your diet
- Have a family history of high blood pressure
- Have diabetes
Most of the time, no cause is identified. This is called essential hypertension.
High blood pressure that is caused by another medical condition or medication is called secondary hypertension. Secondary hypertension may be due to:
- Alcohol abuse
- Autoimmune disorders such as periarteritis nodosa
- Chronic kidney disease
- Coarctation of the aorta
- Cocaine use
- Diabetes (if it causes kidney damage)
- Endocrine disorders, such as adrenal tumors (pheochromocytoma, aldosteronism), thyroid disorders, and Cushing syndrome
- Appetite suppressants
- Birth control pills
- Certain cold medications
- Migraine medications
- Renal artery stenosis
Most of the time, there are no symptoms. Symptoms that may occur include:
- Ear noise or buzzing
- Irregular heartbeat
- Vision changes
If you have a severe headache or any of the symptoms above, see your doctor right away. These may be signs of a complication or dangerously high blood pressure called malignant hypertension.
Signs and tests
Your health care provider will perform a physical exam and check your blood pressure. If the measurement is high, your health care provider may think you have high blood pressure. The measurements need to be repeated over time, so that the diagnosis can be confirmed.
If you monitor your blood pressure at home, you may be asked the following questions:
- What was your most recent blood pressure reading?
- What was the previous blood pressure reading?
- What is the average systolic (top number) and diastolic (bottom number) reading?
- Has your blood pressure increased recently?
Other tests may be done to look for blood in the urine or heart failure. Your doctor will look for signs of complications in your heart, kidneys, eyes, and other organs in your body.
These tests may include:
The goal of treatment is to reduce blood pressure so that you have a lower risk of complications. You and your health care provider should set a blood pressure goal for you.
There are many different medicines that can be used to treat high blood pressure, including:
- Alpha blockers
- Angiotensin-converting enzyme (ACE) inhibitors
- Angiotensin receptor blockers (ARBs)
- Beta blockers
- Calcium channel blockers
- Central alpha agonists
- Renin inhibitors, including aliskiren (Tekturna)
Your health care provider may also tell you to exercise, lose weight, and follow a healthier diet. If you have pre-hypertension, your health care provider will recommend the same lifestyle changes to bring your blood pressure down to a normal range.
Often, a single blood pressure drug may not be enough to control your blood pressure, and you may need to take two or more drugs. It is very important that you take the medications prescribed to you. If you have side effects, your health care provider can substitute a different medication.
In addition to taking medicine, you can do many things to help control your blood pressure, including:
- Eat a heart-healthy diet, including potassium and fiber, and drink plenty of water.
- Exercise regularly -- at least 30 minutes a day.
- If you smoke, quit -- find a program that will help you stop.
- Limit how much alcohol you drink -- 1 drink a day for women, 2 a day for men.
- Limit the amount of sodium (salt) you eat -- aim for less than 1,500 mg per day.
- Reduce stress -- try to avoid things that cause stress for you. You can also try meditation or yoga.
- Stay at a healthy body weight -- find a weight-loss program to help you, if you need it.
Your health care provider can help you find programs for losing weight, stopping smoking, and exercising. You can also get a referral from your doctor to a dietitian, who can help you plan a diet that is healthy for you.
Your health care provider may ask you to keep track of your blood pressure at home. Make sure you get a good quality, well-fitting home device. It will probably have a cuff with a stethoscope or a digital readout. Practice with your health care provider or nurse to make sure you are taking your blood pressure correctly.
Most of the time, high blood pressure can be controlled with medicine and lifestyle changes.
- Aortic dissection
- Blood vessel damage (arteriosclerosis)
- Brain damage
- Congestive heart failure
- Chronic kidney disease
- Heart attack
- Hypertensive heart disease
- Peripheral artery disease
- Pregnancy complications
- Vision loss
Calling your health care provider
If you have high blood pressure, you will have regularly scheduled appointments with your doctor.
Even if you have not been diagnosed with high blood pressure, it is important to have your blood pressure checked during your yearly check-up, especially if someone in your family has or had high blood pressure.
Call your health care provider right away if home monitoring shows that your blood pressure remains high or you have any of the following symptoms:
- Chest pain
- Excessive tiredness
- Nausea and vomiting
- Shortness of breath
- Significant sweating
- Vision changes
Adults over 18 should have their blood pressure checked routinely.
Lifestyle changes may help control your blood pressure:
- Avoid smoking. (See: Nicotine withdrawal)
- Do not consume more than 1 drink a day for women, 2 a day for men.
- Eat a diet rich in fruits, vegetables, and low-fat dairy products while reducing total and saturated fat intake (the DASH diet is one way of achieving this kind of dietary plan). (See: Heart disease and diet)
- Exercise regularly. If possible, exercise for 30 minutes on most days.
- If you have diabetes, keep your blood sugar under control.
- Lose weight if you are overweight. Excess weight adds to strain on the heart. In some cases, weight loss may be the only treatment needed.
- Try to manage your stress.
Follow your health care provider's recommendations to modify, treat, or control possible causes of secondary hypertension.
Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7). Rockville, Md. National Heart, Lung, and Blood Institute, US Department of Health and Human Services; August 2004. National Institutes of Health Publication No. 04-5230.
Kaplan NM. Systemic Hypertension: Therapy. In: Libby P, Bonow RO, Mann DL, Zipes DP, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 41.
Wolff T, Miller T. Evidence for the reaffirmation of the U.S. Preventive Services Task Force recommendation on screening for high blood pressure. Ann Intern Med. 2007;147:787-791.
Blumenthal JA, Babyak MA, Hinderliter A, Watkins LL, Craighead L, Lin PH, et al. Effects of the DASH diet alone and in combination with exercise and weight loss on blood pressure and cardiovascular biomarkers in men and women with high blood pressure: the ENCORE study. Arch Intern Med. 2010;170:126-135.
Reviewed By: A.D.A.M. Editorial Team: David Zieve, MD, MHA, and David R. Eltz. Previously reviewed by David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine (5/26/2010).