People with high blood pressure, or hypertension, have a systolic pressure of 130 millimeters of mercury (mm Hg) or higher, or a diastolic pressure of 80 mm Hg or higher.
High blood pressure often does not cause any noticeable symptoms. However, it can lead to serious health complications, such as heart disease and stroke.
In this article, we outline the distinction between normal and high blood pressure readings and describe the factors that can cause or contribute to high blood pressure. We also provide information on how to treat high blood pressure.
Blood pressure readings indicate the force with which the heart pumps blood around the body. These readings take into account two different types of blood pressure: systolic and diastolic.
Systolic pressure measures the degree of blood pressure within the arteries as the heart contracts. Diastolic pressure measures the degree of blood pressure within the arteries as the heart rests between contractions.
Blood pressure monitors display the systolic pressure above the diastolic pressure. For example, the monitor may display the reading 120/80 mm Hg, indicating a systolic pressure of 120 mm Hg and a diastolic pressure of 80 mm Hg.
A healthcare provider will assign a person’s blood pressure reading to one of the following five categories (all measurements are in mm Hg):
- Normal: A systolic pressure below 120 with a diastolic pressure below 80.
- Elevated: A systolic pressure of between 120 and 129 with a diastolic pressure below 80.
- High blood pressure (hypertension stage 1): A systolic pressure of between 130 and 139, or a diastolic pressure between 80 and 89.
- High blood pressure (hypertension stage 2): A systolic pressure of 140 or higher, or a diastolic pressure of 90 or higher.
- Hypertensive crisis: A systolic pressure greater than 180, a diastolic pressure greater than 120, or both. A person who is experiencing a hypertensive crisis should consult their doctor immediately.
High blood pressure tends to affect certain groups of people more than others. Some examples include those below.
According to a 2015 review, males below the age of 65 are more likely to experience hypertension than females belonging to the same age group.
Age is an unavoidable risk factor for developing high blood pressure. According to the National Institute on Aging, a blood pressure reading of 130/80 mm Hg or higher would indicate high blood pressure in an older adult.
Isolated systolic hypertension is a type of high blood pressure that results from age-related stiffening of the arteries. It causes a systolic pressure of 130 mm Hg or higher alongside a diastolic pressure below 80 mm Hg. Doctors treat this type of hypertension in the same way that they treat regular hypertension.
People who have overweight
Body weight can play a role in the development of high blood pressure. According to the AHA, a person with overweight can decrease their blood pressure by losing as little as 5 or 10 pounds.
For people who have overweight or obesity, losing weight also helps reduce the risk of certain health conditions, including:
Women can develop high blood pressure during pregnancy. Likewise, individuals with a history of high blood pressure can continue to experience this throughout their pregnancy.
According to the National Library of Medicine, three types of high blood pressure can affect women during pregnancy. They are:
- Chronic hypertension: High blood pressure that developed either before the pregnancy or before the 20th week of the pregnancy.
- Gestational hypertension: High blood pressure that begins after the 20th week of pregnancy. This type is not usually dangerous to the woman or the fetus. Women who develop gestational hypertension usually find that their blood pressure returns to normal within 12 weeks of giving birth.
- Preeclampsia: A rapid rise in blood pressure that is most common during the third trimester of pregnancy. Preeclampsia can damage the kidneys and liver, and it can be life threatening to both the woman and the fetus.
Women should monitor their blood pressure regularly when pregnant. They should talk to their doctor if their blood pressure readings begin to rise or they experience any of the following symptoms of preeclampsia:
Several factors can affect a person’s blood pressure. Some of these factors are controllable, whereas others are not. Below are some examples of each.
Factors that a person can control
Below are some potentially avoidable risk factors for having or developing high blood pressure:
- drinking alcohol
- having overweight
- not exercising regularly
- eating too much salt
- not having enough potassium in the diet
- having a vitamin D deficiency
- taking cough and cold medications
- taking nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen
- experiencing elevated stress levels
Factors that a person cannot control
It is not possible to control some factors that can increase the risk of high blood pressure. According to the Centers for Disease Control and Prevention (CDC), such factors may include:
- biological sex
- a family history of high blood pressure
A person who has high blood pressure will need to take steps to manage it. These steps will include taking regular blood pressure measurements at home.
A person may also need to make certain lifestyle changes, such as:
- quitting smoking
- limiting alcohol intake
- managing stress levels
- achieving or maintaining a moderate weight through diet and exercise
- eating a healthful, balanced diet that is low in salt
In addition to making lifestyle changes, a person may need to take medication to help manage their blood pressure. According to the CDC, blood pressure medications work by doing at least one of the following:
- reducing the amount of salt and water in the body
- relaxing the blood vessels
- blocking nerve activity that can restrict the blood vessels
- reducing the force of the heartbeat
In some cases, it may be necessary to take more than one type of blood pressure medication. A person should take the appropriate dose of each medication at the same time each day to maximize the effectiveness of the treatment.
Anyone whose home blood pressure readings remain high or begin to elevate again should speak to their doctor. The doctor may need to adjust the dosage of the medication or prescribe an alternative.
Without treatment, high blood pressure can lead to several health complications. According to the National Heart, Lung, and Blood Institute, common complications include:
- vascular dementia
- eye damage
- chronic kidney disease
- carotid artery disease or peripheral artery disease
- heart attack or heart failure
A person who has high blood pressure may not experience symptoms until they develop a related health complication.
The AHA recommend that a person contact their doctor if they have a reading of 180/120 mm Hg or higher twice within 5 minutes. Their doctor will likely recommend adjusting the dosage of a current medication or adding a new one.
If symptoms of a hypertensive emergency accompany a high blood pressure reading, a person should call 911 or go to their nearest emergency room immediately. Symptoms of a hypertensive emergency include:
Women who are pregnant should seek medical advice if they experience symptoms of high blood pressure during their pregnancy.
In most cases, a person can bring their high blood pressure under control with the appropriate lifestyle changes and medical treatments.
Successful management of high blood pressure will lower a person’s risk of health complications, such as stroke, heart disease, and type 2 diabetes.
High blood pressure, or hypertension, is a common condition. It typically does not cause symptoms until a person develops complications, such as a heart attack or stroke.
A person who has high blood pressure may need to make lifestyle changes and take medications to bring their blood pressure under control.
People should talk to their doctor if the steps that they are taking to lower their blood pressure are not working. Anyone who develops symptoms of a hypertensive emergency should seek emergency medical treatment.