What is Hypertension? Symptoms & Causes of High Blood Pressure

Hypertension, also known as high blood pressure, is a very common condition.¹n High blood pressure happens when blood moving through the body pushes ntoo much on the walls of the arteries, which are a type of blood vessel.¹n Nearly half of American adults have high blood pressure.1 Learn more nabout high blood pressure, its symptoms, and its long-term effects.

What Is Hypertension?

Hypertension is high blood pressure.² High blood pressure is sometimes abbreviated as HBP.

There are two main types of high blood pressure.³n Primary hypertension is high blood pressure that has no identifiable ncause. Most cases of high blood pressure are primary hypertension.

Secondaryn hypertension is a form of high blood pressure that is caused by a nmedical condition that was present before the high blood pressure ndiagnosis.³ In most cases, if the initial condition resolves,n the blood pressure will also return to normal. Secondary hypertension nis responsible for only a small portion of hypertension cases.

What Are High Blood Pressure Symptoms?

High blood pressure usually doesn’t cause any obvious symptoms, especially in the beginning stages.^1,2n A lot of people don’t even know they might have it. About 1 in 3 U.S. nadults with high blood pressure don’t even know that they have it and naren’t being treated.² That’s why high blood pressure is frequently called a "silent killer".^1,4

Bloodn spots in the eyes, facial flushing, and dizziness may be indirectly nassociated with high blood pressure, but these are not causes or signs nof high blood pressure.⁴

Some people think that high blood pressure can cause headaches and nosebleeds, but that’s not usually true in most cases.⁴ If you have a headache or nosebleed and your blood pressure is nunusually high, this might be a hypertensive crisis. A hypertensive ncrisis is a medical emergency that requires medical attention.

What Causes High Blood Pressure?

Most cases of high blood pressure are primary hypertension and have no identifiable cause.³ High blood pressure develops gradually over time.⁵ There are a number of factors that can increase a person’s risk of developing high blood pressure.³n These risk factors can be divided into two groups: factors that can’t nbe changed (nonmodifiable) and factors that can be changed (modifiable).

Nonmodifiable risk factors include family history, age, and gender.³ Having a close blood relative (e.g., parent, sibling) with high blood npressure can increase the risk of developing high blood pressure. nGenerally, increasing age increases the risk. Gender also affects risk. Before the age of 64, men have an increased risk of developing high nblood pressure. After 65 years or more, women have an increased risk of ndeveloping high blood pressure.

Race is another nonmodifiable risk factor that can affect a person’s risk of developing high blood pressure.³n In the U.S., Black people tend to develop high blood pressure more noften than people of any other racial background. About 55% of Black adults have high blood pressure.⁶ These patients also tend ton have higher rates of more severe high blood pressure and tend to be ndiagnosed earlier in their lives than people of other racial nbackgrounds. Historical and systemic factors, like not having access to ncare and healthy foods and other societal issues, are major contributorsn to the imbalance of high blood pressure diagnoses among Black adults inn the community.

Modifiable risk factors that can increase the risk of developing high blood pressure include:³

• Lack of physical activity
• Unhealthy diet (such as a diet high in salt, calories, fat, and sugar)
• Excess body weight
• Regular, excessive alcohol consumption
• Obstructive sleep apnea
• High cholesterol
• Diabetes
• Smoking and tobacco use and exposure
• Excess stress

How Is Blood Pressure Measured?

An healthcare provider usually measures the blood pressure using an ninflatable cuff placed on the arm and a stethoscope, gauge, or nelectronic sensor.^{2, 7} Checking blood pressure is easy and painless.²

There are a few things that patients can do to help get the most accurate blood pressure measurement.^{2, 7}

• Wear clothing that can be removed or easily moved so clothing is not covering the location of the cuff.
• Avoid caffeine, exercise, and smoking within 30 minutes of having blood pressure measured.
• Go to the bathroom before the measurement.
• Sitn in a chair with the feet on the floor, the back supported, and the arm nresting on a table at the level of the heart. Relax here for more than 5n minutes before the measurement.
• Do not speak during the blood pressure measurement.

When a healthcare provider checks the blood pressure of a patient for the first time, they might check it in both arms.^{2, 7} If the measurement is higher in one arm than the other, they should ncontinue to measure the blood pressure in the arm that gives the higher nmeasurement.⁷

What Do the Numbers in a Blood Pressure Measurement Mean?

There are two numbers in a blood pressure measurement.⁸n The first number is the force of blood on the artery walls when the heart beats and blood is pumped out of the heart. This number is called nthe systolic (si-stol-ik) blood pressure, or SBP. The second number is the force of blood on the artery walls when the heart is filling up withn blood in between beats. This number is called the diastolic (dy-uh-stol-ik) pressure, or DBP.

Blood pressure is measured in the units of millimeters of mercury.^{2, 8} This is because the first pressure gauges used to accurately measure nblood pressure used mercury. Millimeters of mercury is often abbreviatedn as mm Hg.

Blood pressure measurements include both the systolic nand diastolic blood pressure numbers with a "/" in between, like a fraction.^{2, 8} When people talk about blood pressure, the 2 numbers are separated by the word “over”, to represent the fraction. Forn example, 120/80 is usually called "120 over 80."

How Is High Blood Pressure Diagnosed?

High blood pressure is usually diagnosed using multiple measurements of the blood pressure taken at a doctor’s office or clinic.² An average of at least two blood pressure measurements on at least two separate occasions are used to make the diagnosis.⁷

Normaln blood pressure is when systolic blood pressure measurements are usuallyn less than 120 mm Hg and diastolic blood pressure measurements are nusually less than 80 mm Hg.^{7, 8}

Elevated blood pressuren is when systolic blood pressure measurements are usually in the range nof 120-129 mm Hg and diastolic blood pressure measurements are usually nless than 80 mm Hg.^{7, 8} Patients with elevated blood pressure often progress to having high blood pressure unless they make lifestyle changes.⁸

High blood pressure can be divided into two stages:^{7, 8}

• Stagen 1 is when systolic blood pressure measurements are usually in the rangen of 130-139 mm Hg or when diastolic blood pressure measurements are nusually in the range of 80-89 mm Hg.
• Stage 2 is when systolic nblood pressure measurements are usually at least 140 mm Hg or when ndiastolic blood pressure measurements are usually at least 90 mm Hg.

Blood pressures of more than 180/120 mm Hg might be a hypertensive crisis.⁸ A hypertensive crisis is a medical emergency that requires medical attention.

What Are the Long-Term Effects of Hypertension?

Hypertensionn can result in long-term effects to the body. Blood vessels become ndamaged when the blood pressure remains high over time.⁹ Cholesterol can build up in the injured blood vessels. This causes the arteries to become stiffer and narrower.

High blood pressure that is not diagnosed or is uncontrolled can lead to nserious health problems. Some of these health problems include:^{2, 9}

• Aneurysm
• Chest pain
• Heart attack
• Heart failure
• Chronic kidney disease or kidney failure
• Eye damage/vision loss
• Peripheral artery disease or carotid artery disease
• Sexual dysfunction
• Stroke

High Blood Pressure Prevention

The best way to reduce the risk of developing high blood pressure is by living a healthy lifestyle.^{2, 7, 10} This can involve:

• Eating healthy foods that are low in salt and high in potassium
• Limiting alcohol
• Keeping physically active
• Maintaining a healthy body weight
• Quitting smoking
• Managing stress
• Getting enough sleep

Resources for Learning More About High Blood Pressure

Some trusted resources for learning more about high blood pressure include:

• The Facts About High Blood Pressure – American Heart Association (AHA)
• Learn About High Blood Pressure – Centers for Disease Control and Prevention (CDC)
• What Is High Blood Pressure – National Heart, Lung, and Blood Institute (NHLBI)

Sources

1. High Blood Pressure. National Heart, Lung, and Blood Institute. Updated March 24, 2022. Accessed October 10, 2022. https://www.nhlbi.nih.gov/health/high-blood-pressure
2. The Facts About High Blood Pressure. American Heart Association. Updated November 30, 2017. Accessed October 10, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/the-facts-about-high-blood-pressure
3. Know Your Risk Factors for High Blood Pressure. American Heart Association. Updated December 31, 2017. https://www.heart.org/en/health-topics/high-blood-pressure/why-high-blood-pressure-is-a-silent-killer/know-your-risk-factors-for-high-blood-pressure
4. What are the Symptoms of High Blood Pressure? American Heart Association. Updated October 31, 2016. Accessed October 10, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/why-high-blood-pressure-is-a-silent-killer/what-are-the-symptoms-of-high-blood-pressure
5. Why High Blood Pressure is a “Silent Killer”. American Heart Association. Updated November 31, 2017. Accessed October 10, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/why-high-blood-pressure-is-a-silent-killer/know-your-risk-factors-for-high-blood-pressure
6. High Blood Pressure Among Black People. American Heart Association. Updated March 4, 2022. Accessed October 10, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/why-high-blood-pressure-is-a-silent-killer/high-blood-pressure-and-african-americans
7. Wheltonn PK, Carey RM, Aronow WS, et al. 2017 nACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the nPrevention, Detection, Evaluation, and Management of High Blood Pressuren in Adults: Executive Summary: A Report of the American College of nCardiology/American Heart Association Task Force on Clinical Practice nGuidelines. Hypertension. 2018;71:1269-1324.
8. Understanding Blood Pressure Readings. American Heart Association. Accessed October 11, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/understanding-blood-pressure-readings
9. Health Threats from High Blood Pressure. American Heart Association. Updated March 4, 2022. Accessed October 11, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/health-threats-from-high-blood-pressure
10. Changes You Can Make to Manage High Blood Pressure. American Heart Association. November 30, 2017. Accessed October 11, 2022. https://www.heart.org/en/health-topics/high-blood-pressure/changes-you-can-make-to-manage-high-blood-pressure