What is hypertension?

The heart works like a pump, sending blood rich in oxygen and nutrients throughout the body, and the pressure the moving blood exerts on the vessel walls is called blood pressure. The highest pressure, exerted on the vessel walls as the heart contracts, is the systolic blood pressure, and the pressure while the heart relaxes (expands) and takes in blood is the diastolic blood pressure. A reading of 140/90 mmHg (systolic/diastolic) or higher is defined as hypertension.
Ideal blood pressure is 115/75mmHg, and office blood pressure above 140/90mmHg is called hypertension.

Causes of hypertension

About 90~95% of hypertension is essential (primary) hypertension, with no identifiable cause.
The remaining 5-10% is secondary hypertension, in which blood pressure rises because of an underlying condition such as kidney, adrenal or thyroid disease or narrowing of a blood vessel; in these cases blood pressure returns to normal once the underlying disease is treated.

Hypertension symptoms

Most hypertension causes no symptoms. People often assume that dizziness, headache, neck stiffness or pain means high blood pressure, but most of these symptoms have little to do with hypertension, so there is no way to know other than measuring blood pressure regularly.
Exceptionally, if diastolic blood pressure rises above 110mmhg, headache may occur, along with swelling, palpitations, headache and dizziness.