Blood Pressure

Blood Pressure

Blood pressure is defined as the pressure that is exerted by the blood on the walls of the blood vessels, particularly the arteries. Blood pressure is affected by many factors including: the strength of the heart muscle contractions, blood volume and viscosity, overall health of the body’s blood vessels, and the age and health of the individual. When blood pressure is abnormally high, this is called “Hypertension”.

How is blood pressure measured?

Blood pressure is measured as two numbers: “Systolic” Pressure (when the heart muscle contracts pushing blood into the circulatory system) and “Diastolic” Pressure (when the heart relaxes following contraction to allow it to refill with blood). Blood pressure readings are expressed as systolic pressure “over” diastolic pressure and written as: 120/80 This level is the “benchmark” for a healthy resting blood pressure.

For the blood pressure to be accurately measured, a person should be sitting quietly for at least 5 minutes. The blood pressure cuff should be placed on the bare (not over clothing) upper arm, and 2 or 3 separate measurements made over several minutes, and the average of the readings recorded.

When am I at risk?

If your resting blood pressure is consistently above the benchmark 120/80 level at rest, you may be at increased risk for many of the adverse effects of hypertension over time. These can include any combination of the following: a stroke caused by bleeding from or blockage of arteries in the brain, damage to the retina of the eye with loss of vision, coronary artery heart disease, heart attack, heart failure, kidney damage leading to kidney failure, and vascular atherosclerotic changes (“hardening of the arteries”) including the development of areas of stenosis (severe narrowing with restriction of blood flow) and aneurysms (weakening of areas of the artery walls causing ballooning with pressure on surrounding tissues or rupture with bleeding).

For both men and women, long term exposure to elevated blood pressure has also been found to be a cause earlier sexual dysfunction (erectile dysfunction in men and vaginal effects in women leading to decreased desire, arousal and difficulty achieving orgasm).

American Heart Association / American College of Cardiology Blood Pressure Guidelines
CategorySystolic Reading (upper number)and/orDiastolic Reading (lower number)
NormalLess than 120ANDLess than 80
Elevated120-129ANDLess than 80
High Blood Pressure (Hypertension) Stage 1130-139OR80-89
High Blood Pressure (Hypertension) Stage 2140 or higherOR90 or higher
Hypertension Crisis (consult your physician immediately)higher than 180AND/ORHigher than 120

Additional Resources

Further information on blood pressure available at the following sites:

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