An unknown cause of higher than normal blood pressure.  In adults when at rest, the systolic pressure is equal to or above 140mm Hg and the diastolic pressure is usually equal to or above 90mm Hg.  It is  also referred to as primary hypertension. 

The increase of blood pressure is due to the narrowing of peripheral blood vessels often leading to dysfunction of the kidneys. High blood pressure can result from overweight, stress, smoking, alcoholism, diabetes, or a di...more