What is Blood Pressure?

In simplest terms, blood pressure is the force of blood against the walls of arteries. Blood pressure is recorded as the measure of systolic pressure over diastolic pressure, so if you hear the numbers 120/80, you now know that the first number refers to systolic and the second to diastolic pressure.

Typically, more attention is given to systolic blood pressure (the top number) as a major risk factor for cardiovascular disease for people over 50. In most people, systolic blood pressure rises steadily with age due to the increasing stiffness of large arteries, long-term build-up of plaque and an increased incidence of cardiac and vascular disease.

However, elevated systolic or diastolic blood pressure alone may be used to make a diagnosis of high blood pressure. And, according to recent studies, the risk of death from ischemic heart disease and stroke doubles with every 20 mm Hg systolic or 10 mm Hg diastolic increase among people from age 40 to 89.

Systolic Blood Pressure

  • The force of blood as the heart beats
  • The top number in a blood pressure reading
  • >120 mmHg = elevated systolic blood pressure
  • Systolic blood pressure does not need to be high for you to have high blood pressure

Diastolic Blood Pressure

  • The force of blood as the heart relaxes between beats
  • The bottom number in a blood pressure reading
  • 80-89 mmHg = high diastolic blood pressure
  • The higher the diastolic number, the greater the risk for heart attacks, strokes, and kidney failure—especially in younger people

High Blood Pressure (HBP)

  • Medically defined as hypertension
  • A.K.A. the “silent killer” because there are no obvious symptoms
  • Nearly half of American adults have high blood pressure
  • High blood pressure increases your chance/risk for developing heart disease, stroke, heart failure, kidney disease, vison loss, sexual dysfunction, peripheral artery disease (PAD)

Risk Factors

Unmodifiable Risk Factors (factors out of your control):

  • Family history: If your parents or other close blood relatives have HBP, there is an increased chance you will get it too
  • Age: The older you are the more likely you will develop HBP
  • Gender: Males before the age of 64 are more likely to develop HBP than females. Females 65 and older are more likely to develop HBP
  • Race: African-Americans tend to develop HBP more often than any other racial backgrounds in the United States
  • Chronic Kidney Disease: Kidney disease may lead to the development of HBP. Having HBP may also cause further kidney damage

Modifiable Risk Factors (factors you can control):

  • Smoking and tobacco use: Using tobacco increases you blood pressure and can damage your arteries. Secondhand smoke exposure also increases your risk.
  • Physical inactivity: Not getting enough physical activity as part of your daily lifestyle increases your chances of developing HBP
  • Unhealthy diet: Diets high in salt, saturated fats, trans fats, sugar, and calories increases your chances of developing HBP
  • Being overweight or obese: Carrying too much weight can cause your heart and circulatory system to work too hard, causing serious health problems including HBP
  • Alcohol use: Regular, heavy alcohol use can cause serious health problems including HBP
  • Stress: Too much stress cause HBP and can cause you to engage in behaviors, such as drinking, smoking, or eating too much, that can increase blood pressure
  • High cholesterol: High cholesterol levels can damage your heart and circulatory system, which can increase your blood pressure
  • Diabetes: Having diabetes can increase your blood pressure
  • Sleep apnea: Obstructive sleep apnea may increase your risk of developing HBP

What is Considered High BP?

  • ≥130 systolic or ≥80 diastolic
  • Both systolic and diastolic numbers are important in determining high blood pressure
  • If your blood pressure is >180 systolic and/or >120 diastolic while at rest, wait 5 minutes and check it again. If your reading is still unusually high, consult your doctor immediately

Blood Pressure Levels (mmHg)

Category Systolic / Diastolic

Normal systolic <120 and diastolic <80
Elevated (Pre-hypertension) systolic 120-129 and diastolic <80
Stage 1 Hypertension systolic 130-139 or diastolic 80-89
Stage 2 Hypertension systolic ≥140 or diastolic ≥90

Crisis systolic >180 and/or diastolic >120

Risks associated with high blood pressure


  • High BP can cause a break in weakened blood vessels, which then bleeds to the brain
  • A blood clot blocking a narrowed artery can also cause a stroke

Impaired Vision:

  • High BP can cause blood vessels in the eyes to burst or bleed, making vision blurred and resulting in blindness


  • High BP is associated with hardening of the arteries—arteriosclerosis—in the heart, brain, and kidneys
  • As arteries harden, their pathways for blood flow become narrower, causing the heart and kidneys to work harder

Kidney Damage:

  • Kidneys serve to filter our bodies of waste products
  • High BP can narrow and thicken the blood vessels of the kidneys, resulting in waste product build-up in the blood
  • Eventually the kidneys could fail, resulting in dialysis or a kidney transplant

Heart Attack/Myocardial Infarction:

  • Arteries bring oxygen-carrying blood to the heart muscle
  • If the heart cannot get enough oxygen, chest pain—angina pectoris—can occur
  • When the flow of blood is blocked by a clogged artery, the result is a heart attack

Congestive Heart Failure (CHF):

  • High BP is the number one risk factor for CHF
  • CHF is a serious condition in which the heart is unable to pump enough blood to supply the body’s needs

For more information regarding blood pressure please visit: www.heart.org