High Blood Pressure (Hypertension)
What is high blood pressure?
Blood pressure is a measure of the force that the flow of blood exerts on the walls of arteries as it flows through them; high blood pressure (medically known as hypertension) is when blood flow through the arteries creates too much force. Increased force is a consequence of diseased or damaged arterial walls: There is more resistance within the artery walls to blood flowing through them, so the heart has to work harder to force the same amount of blood through the more rigid and narrower vessels.
Hypertension is a very common condition, affecting 50% of Americans ages 20 and older, or about 103 million U.S. adults. This translates to 1 in 3 people in the United States. Unfortunately, many people do not know they have high blood pressure due to the lack of evident symptoms.
A blood pressure measurement has two numbers with the units of pressure, mm Hg (millimeters of mercury). The top number is systolic pressure. It is the highest pressure in your arteries as the heart is pumping blood. The bottom number is diastolic pressure. It reflects the lowest pressure in your arteries when the heart is at rest, between beats. Normal blood pressure is defined as lower than 120/80 mm Hg. A blood pressure reading of 130/80 mm Hg or higher is hypertension. Elevated blood pressure—120/80 to 129/80—is prehypertension.
Blood pressure varies naturally and can moderately rise and fall in response to many situations. For example, blood pressure will rise during strenuous activity or in stressful situations. Blood pressure is normally lower during periods of relaxation or sleep. Because of this, one high blood pressure reading does not mean you have hypertension. A high blood pressure diagnosis requires at least three high readings at different times. Ideally, these readings should take place at least one minute apart while you are resting.
There is no single cause of primary high blood pressure, the most common type. It usually develops slowly over the course of time, so age is a strong predictor of primary hypertension. Age-related changes in blood vessels, various lifestyle habits, and genetic predisposition can all affect blood pressure. Race is also a factor, as more non-Hispanic Black adults have high blood pressure than non-Hispanic white, Hispanic, and Asian American adults.
Chronic, uncontrolled high blood pressure is a serious condition. It can lead to and complicate many health problems, including heart disease, kidney failure, and stroke. It is often called “the silent killer” because it generally has no symptoms until serious complications develop.
Extremely high blood pressure that occurs suddenly or the long-term effects of mild to moderately high blood pressure over time can lead to life-threatening complications, such as stroke, kidney failure, and heart attack. Seek regular medical care to check for and promptly treat high blood pressure to reduce the risk of complications.
Seek immediate medical care (call 911) for such symptoms as chest pain, passing out, difficulty breathing, confusion, slurred speech, vision problems, severe headache, or problems with moving any part of the body, as these can signal a potentially life-threatening event.
What blood pressure numbers define hypertension?
Hypertension categories reflect blood pressure numbers:
Normal blood pressure: a reading of less than 120/80 mm Hg
Elevated blood pressure: a systolic reading of 120 to 129 mm Hg with a diastolic reading under 80 mm Hg. Left untreated, this category, also known as prehypertension, will likely worsen with time.
Stage I hypertension: a systolic reading of 130 to 139 mm Hg or a diastolic reading of 80-89 mm Hg
Stage II hypertension: a systolic reading of 140 mm Hg or higher or a diastolic reading of 90 mm Hg or higher
- Hypertensive crisis: a systolic reading higher than 180 mm Hg or a diastolic reading higher than 120 mm Hg. Another name for it is stage III (stage 3) hypertension. When blood pressure is 180/120 or higher and there are signs of organ damage, it is malignant, or accelerated, hypertension. This is a hypertensive emergency and requires immediate medical care.
What are the different types of hypertension?
Primary and secondary high blood pressure are the two main forms of the disease. Primary high blood pressure is the most common form, affecting 85% of people with hypertension. A combination of factors—faulty genes, environmental factors, and others—bring on primary high blood pressure, also known as essential hypertension.
Secondary hypertension is a result, or secondary effect, of other primary medical conditions, such as kidney disease.
What are the symptoms of high blood pressure?
High blood pressure usually does not cause any symptoms. The only way to diagnose it is to measure it. This is why it is often called “the silent killer.” Many people do not realize they have it until serious complications develop. In some cases, people with high blood pressure may experience nosebleeds or headaches.
Serious symptoms that might indicate a life-threatening condition
In some cases, high blood pressure can be life-threatening, such as hypertensive crises with organ damage. High blood pressure can also accompany symptoms indicating a serious or life-threatening condition that needs immediate evaluation in an emergency setting. Seek immediate medical care (call 911) for any of these symptoms including:
Chest pain, tightness or pressure, or rapid heart rate
Garbled or slurred speech or inability to speak
Nosebleed that does not stop within five minutes
Vision changes, abnormal pupil size, or severe or unusual headache
Regular medical care can help find high blood pressure before serious problems develop. If you have high blood pressure, seeing your doctor on a regular basis is also important. Your doctor will likely have you monitor your blood pressure at home. But regular medical care can help identify early signs of potential complications.
What causes high blood pressure?
Each time the heart beats, it creates a certain amount of pressure (force) against artery walls. Blood pressure is highest when blood is moving out of the heart into arteries. Pressure is lowest when blood is moving into the heart (between heartbeats). High blood pressure is increased resistance to arterial blood flow through smaller blood vessels that have become narrower and more rigid than normal due to age and or disease. Hypertension is another name for sustained high blood pressure, as tension increases within the walls. The heart has to work harder than normal to push, or force, the same amount of blood through the blood vessels.
In most cases, high blood pressure has no known direct cause. This is primary—or essential—hypertension. It usually develops slowly over the course of time. Instead of a direct cause, there are indirect causes, such as age-related changes in blood vessels, various lifestyle habits, and genetic predisposition. Scientists have identified dozens of genes associated with high blood pressure.
High blood pressure can also develop due to an underlying condition or medication. This is secondary hypertension. It tends to occur more suddenly than primary hypertension.
Common conditions that can cause secondary hypertension include kidney problems, thyroid disorders, and adrenal gland tumors. Obstructive sleep apnea can also contribute to high blood pressure.
Medications that can lead to high blood pressure include hormonal birth control, cold medicines, corticosteroids, and NSAIDs (nonsteroidal anti-inflammatory drugs). Cocaine and methamphetamine can also cause it.
What are the risk factors for high blood pressure?
High blood pressure is linked to several risk factors. However, not all people who are at risk for high blood pressure will develop it. And not all people who develop high blood pressure have risk factors.
Risk factors include:
Age: High blood pressure becomes more common as you age.
Family history of high blood pressure
Gender: Males have a higher risk until age 64. After age 65, the risk is higher in females.
Other medical conditions: Diabetes, high cholesterol, anxiety, stress and prehypertension (elevated blood pressure) all increase the risk.
Race: High blood pressure is more common in African Americans. It tends to develop at a younger age and results in more serious complications, such as heart attack, in this group.
Lifestyle habits and behaviors can also increase the risk of high blood pressure. This includes:
Drinking alcohol excessively
Eating a high-salt diet
Leading a sedentary lifestyle
Smoking or using nicotine
How do you prevent high blood pressure?
Changing risk factors you can control is the main way to prevent high blood pressure. There are several healthy behaviors you can adopt to reduce your risk of high blood pressure, including:
Eating a healthy diet low in salt and high in fiber, whole grains, and fresh fruits and vegetables
Getting regular physical exercise, with 30 minutes of moderate-intensity activities (like walking briskly) five days a week
Maintaining a healthy weight
Stopping smoking or using other forms of nicotine
It is also important to seek regular medical care for other medical conditions that contribute to high blood pressure.
What are the diet and nutrition tips for high blood pressure?
A chronically high-salt diet stresses the kidneys, which leads to fluid buildup and higher blood pressure. As far back as the 1990s, doctors discovered a low-sodium diet alone—reducing salt intake to 1,500 mg/day—can “cure” mild hypertension. The study led to the Dietary Approaches to Stop Hypertension (DASH) diet, which is beneficial for anyone, but particularly people with hypertension and many other cardiovascular conditions as well as type 2 diabetes.
The DASH diet is essentially a heart-healthy diet. It includes:
Fruits that have a low glycemic index (apples, oranges, peaches, plums, pears, grapes, and strawberries)
Healthy fat, such as found in avocados, nuts, flax seeds, and fish
Legumes and beans
Vegetables, particularly green leafy vegetables like broccoli, kale and spinach
Whole grains, including wheat, oats, and ancient grains like millet
When you adopt a blood pressure-friendly diet like the DASH diet, you are also getting foods full of potassium, calcium and magnesium, all of which are beneficial for your cardiovascular system. Avoid unhealthy sources of fat, including margarine, vegetable shortening, and processed and fast foods, which also contain a significant amount of salt.
Ask your healthcare provider for guidance before making significant changes to your diet.
What are some conditions related to high blood pressure?
How do doctors diagnose high blood pressure?
A high blood pressure diagnosis requires several blood pressure measurements to record and confirm it. (The 2017 American Cardiology Association/American Heart Association guideline is more than two measurements at more than two doctor visits.) Healthcare providers commonly measure the arterial pressure in the upper arm, but they may measure both arms and legs as well.
Doctors or other healthcare professionals order additional tests to determine (if possible) an underlying cause and look for signs of organ damage. They may order tests to evaluate other risk factors for heart disease and stroke, such as high cholesterol.
Additional tests may include:
How is high blood pressure treated?
For secondary hypertension, treating the underlying problem, such as kidney disease or an adrenal gland tumor, may return blood pressure to normal. When a medication is responsible for high blood pressure, your doctor may stop it or lower the dose.
There is no cure for primary hypertension, but patients can usually control it with lifestyle changes and, if necessary, high blood pressure medicine. Doctors customize high blood pressure treatment plans based on the type and severity of high blood pressure, disease risk factors, lifestyle, and medical history. Your blood pressure goal will depend on your age and overall health.
The first step in treating high blood pressure is often the same lifestyle changes that can reduce your risk. These changes may be enough to bring elevated blood pressure (prehypertension) under control.
Lifestyle changes for high blood pressure
- Drinking less caffeine, including from coffee and energy drinks
- Eating a heart-healthy diet, including less alcohol and less than 1,500 mg sodium/day
- Exercising more. The physical activity guideline for the general public is 150 minutes of moderate exercise per week, but everyone is different. If you are exercising this amount and not seeing any difference in your blood pressure readings, you may have to exercise harder or more frequently. Ask your doctor for guidance based on your health.
- Not smoking, or quitting if you smoke
- Losing weight for overweight or obese patients
High blood pressure medicine
Sometimes, lifestyle changes alone are not enough to lower blood pressure. When this is the case, doctors prescribe medications to lower blood pressure. The American Heart Association guidelines recommend medication in these circumstances:
- Stage 1 hypertension (130/80 to 139/89 mm Hg) in adults 65 years of age or older
- Stage 1 hypertension and a history or risk of cardiovascular disease (CVD), or stage 1 and patient has diabetes or chronic kidney disease
- Stage 2 or 3 hypertension (140/90 mm Hg or higher)
The type of medication that is best for you depends on how high your blood pressure is and your other medical conditions. Types high blood pressure medications include:
- ACE (angiotensin-converting enzyme) inhibitors, which lower blood pressure by preventing the body from making angiotensin II, a hormone that narrows and tightens blood vessels. These drugs may be particularly helpful for people with kidney disease.
- Alpha blockers, which decrease nerve impulses that tighten blood vessels
- ARBs (angiotensin II receptor blockers), which block the action of angiotensin II. Like ACE inhibitors, people with kidney disease may benefit from an ARB.
- Beta blockers, which lower blood pressure by helping the heart to beat more slowly and less forcefully
- Calcium channel blockers, which relax the blood vessels. These drugs may work better than other high blood pressure medicines in African Americans and older people.
- Centrally-acting agents, which work in the brain to prevent signals that narrow the blood vessels
- Diuretics, which lower blood pressure by stimulating the kidneys to flush extra fluid and salt from the body. “Water pills” is a common name for these drugs. They are often the first choice for treating high blood pressure. Like calcium channel blockers, they may work better than other options in African Americans and the elderly.
- Renin inhibitors, which decrease the production of renin, the enzyme that starts the chain reaction that makes angiotensin II
- Vasodilators, which relax and widen blood vessels
You may start out on one medicine, but it is common to need a combination of medicines to effectively control blood pressure. It can take time to find the right medicine or combination of medicines for you. It involves some trial and error to adjust dosages or change medicines.
Alternative treatments for high blood pressure
While alternative treatments do not substitute for proven hypertension treatments, such as a low-sodium diet and medication when necessary, you can add them to your prescribed treatment plan with doctor supervision. Always inform your doctor of any and all medications, supplements and vitamins you take, as there may be potentially dangerous drug interactions.
Alternative treatments with some evidence for therapeutic benefit include:
- Coenzyme Q10
- Flavonoids, which are plant-based compounds. In particular, dark chocolate, soy protein isolate, and green tea have been shown to reduce blood pressure.
- Garlic extract (aged)
- Meditation or simple deep breathing exercises to reduce stress
- Potassium from food
- Vitamin D, which you can take as a supplement if you are deficient
How does high blood pressure affect quality of life?
High blood pressure is what many heart and vascular specialists refer to as the “silent killer” because there are no symptoms (except for hypertensive crisis), but life-threatening damage to blood vessels and the heart is happening.
The biggest burdens of high blood pressure include:
Four-fold higher risk of dying from stroke
Three-fold higher risk of dying from heart disease
Doctor visits: As a population, Americans make 55 million doctor visits annually for blood pressure treatment
Medical expense: Annual healthcare costs are an estimated $131 billion higher for hypertensive adults as a group compared to people without it.
A heart-healthy lifestyle and high blood pressure medications can control most cases of hypertension to target levels. Typical medications for high blood pressure are inexpensive with insurance (costing less than $10 per month), even without insurance. Unfortunately, nearly half (45%) of people who know they have hypertension do not have it under control.
What are the possible complications of high blood pressure?
When doctors find high blood pressure early, treatment is usually successful in preventing serious complications. However, uncontrolled high blood pressure can result in serious and even life-threatening complications. It can permanently damage the arteries throughout your body, including those that supply blood to vital organs, such as the kidneys, brain and heart.
Complications of uncontrolled high blood pressure include:
Heart attack, coronary artery disease, and heart failure
Kidney failure and other types of organ damage
Vision changes and blindness
Following the treatment plan you and your doctor design offers the best chance of preventing complications from high blood pressure.
Does high blood pressure shorten life expectancy?
Primary hypertension and hypertensive renal disease (high blood pressure due to blocked kidney artery) is listed as the cause of death for about 36,000 people a year (2019) in the United States—among the top 15 causes of death. However, this does not account for deaths due to heart disease (leading cause of death) or stroke (fifth-leading cause of death), for which high blood pressure is a major contributing cause. From 2005 to 2015, the number of deaths due to high blood pressure increased 37%. High blood pressure also shortens life expectancy by about five years.
Hypertensive crisis—when blood pressure quickly rises to 180/120 or higher—can cause stroke, heart attack, kidney and eye damage, aortic dissection, and memory loss, among other complications. Symptoms of hypertensive crisis include severe headache, vision changes, shortness of breath, loss of consciousness, chest pain, nosebleed, and severe anxiety.
High blood pressure awareness
High blood pressure is a preventable and treatable disease, but only half of people with high blood pressure have it under control. Learn more about the long-term effects of high blood pressure and the Million Hearts campaign for cardiovascular disease awareness and prevention.