Essential hypertension refers to high blood pressure with no identifiable cause.

As blood is pumped through your body, it exerts pressure on the walls of your arteries. The systolic blood pressure is the pressure against these walls when the heart contracts, and the diastolic blood pressure is the pressure against these walls when the heart relaxes. When you get a blood pressure reading, you are told the systolic pressure/diastolic pressure.

For example, normal blood pressure is below 120/80.

High blood pressure, also called hypertension, occurs when the systolic pressure is consistently over 140 mm Hg, or the diastolic blood pressure is consistently over 90 mm Hg. Blood pressure is determined by the amount of blood pumped, by the actions of the heart, and by the size and condition of the arteries. Many factors affect blood pressure, including:

• The amount of water in the body
• The amoutn of salt in the body
• The condition of the kidneys, nervous system, and blood vessels
• Various hormone levels in the body

Prehypertension is when your systolic blood pressure is between 120 and 139 or your diastolic blood pressure is between 80 and 89. If you have prehypertension, you are more likely to develop high blood pressure at some point. Therefore, your doctor will recommend lifestyle changes to bring your blood pressure down to normal ranges.

African Americans of both sexes and Caucasian males have a higher rate of significant hypertension. While essential hypertension has no correctable cause, some genetic factors have been identified. Blood vessels become somewhat stiffer as you grow older. For this reason, the rate of high blood pressure increases with age.