2. Important information on blood pressure and its measurement
2.1. How does high/low blood pressure arise?
Your level of blood pressure is determined in the circulatory center of the brain and adjusts to a variety of situa-
tions through feedback from the nervous system. To adjust blood pressure, the strength and frequency of the
heart (Pulse), as well as the width of circulatory blood vessels is altered. Blood vessel width is effected by fine
muscles in the blood vessel walls.
Your level of arterial blood pressure changes periodically during heart activity: During the “blood ejection”
(Systole) the value is highest (systolic blood pressure value). At the end of the heart’s “rest period” (Diastole)
pressure is lowest (diastolic blood pressure value).
Blood pressure values must lie within certain normal ranges in order to prevent particular diseases.
2.2. Which values are normal?
Blood pressure is very high if your diastolic pressure is above 90 mmHg and/or your systolic blood pres-
sure is over 160 mmHg,
while at rest
. In this case, please consult your physician immediately. Long-term
values at this level endanger your health due to continual damage to the blood vessels in you body.
If your systolic blood pressure values are between 140 mmHg and 159mmHg and/or the diastolic
blood pressure values between 90 mmHg and 99mmHg, consult your physician. Regular self-checks
are necessary.
If you have blood pressure values that are too low, (i.e., systolic values under 105mmHg and/or diastolic
values under 60 mmHg), consult your physician.
Even with normal blood pressure values, a regular self-check with your blood pressure monitor is
recommended. You can detect possible changes in your values early and react appropriately.
If you are undergoing medical treatment to control your blood pressure, keep a record of values along with
time of day and date. Show these values to your physician.
Never use the results of your measure-
ments to independently alter the drug doses prescribed by your physician.
Which values are normal?
The following standards for assessing high blood pressure (without regard to age) have been established
by the National Institutes of Health JNCV7, 2003.
3
Category
Systolic
Diastolic
(mmHg)
(mmHg)
Normal
<120
<80
Pre-Hypertension
120-139
80-89
Hypertension
Stage 1 Hypertension
140-159
90-99
Stage 2 Hypertension
>160
>100
