What is Hypertension (high blood pressure)

It is defined in an adult as a systolic pressure of 140 mm Hg or higher and/or a diastolic pressure of 90 mm Hg or higher. It is especially dangerous because it often has no warning signs or symptoms. Hence it is also called as a ‘silent killer’.

Normally, your blood pressure can change from minute to minute, with changes in posture, exercise or sleeping. But it is mainly the systolic pressure which varies, the diastolic pressure varies within narrow limits. Hence a sustained rise of diastolic pressure is of more significance. Therefore, even if the systolic pressure is not high, a constant diastolic pressure of 90 mm hg or more indicates hypertension.