For a young person a typical reading might be 120 systolic and 80
diastolic. These values are expressed in millimetres of mercury and it is
conventional to record the values as systolic/diastolic e.g, 120/80. Blood
pressure in an individual is not a fixed property but varies from minute to
are asleep at night and may become very high when you are startled or understress intense mental arithmetic, for instance, has quite a profound effect. In some subjects blood pressure may rise transiently in response to anxietygenerated by the act of measuring the pressure or attendance at a surgery orhospital clinic. In most cases the blood pressure measured on the first occasionis higher than that recorded on subsequent visits, when patientsare more at ease, Doctors make allowance for this. There is also a tendency for blood pressure torise with age. This particularly affects the systolic pressure and is partly due to
the fact that the larger arteries become harder and lose some of their “give”.
Thus a systolic blood pressure of 145 would be abnormal in a woman of 18, but
would be perfectly acceptable in someone of 70.