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2. IMPORTANT INFORMATION ON THE SUBJECT OF BLOOD PRESSURE AND ITS MEASUREMENT
2.1 How does high or low blood pressure arise?
The level of blood pressure is determined in the circulatory center of your brain and adjusts to a
variety of situations 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 are
altered. Blood vessel width is altered by fine muscles in the blood vessel walls. The level of arte-
rial 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 peri-
od” (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 too high if your diastolic pressure is above 90 mmHg and/or your systolic blood
pressure is over 160 mmHg,
while at rest
. In this case, please consult your physician immediate-
ly. Long-term values at this level endanger your health due to continual damage to the blood ves-
sels in you body.
If your systolic blood pressure values are between 140 mmHg and 160mmHg and/or the diastolic
blood pressure values between 90 mmHg and 95mmHg, 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 measurements 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 JNC7.
Category
Systolic
Diastolic
(mmHg)
(mmHg)
Normal
<120
<80
Self-Check
Pre-Hypertension
120 - 139
80 - 89
Stage 1
140 - 159
90 - 99
Hypertension
Stage 2
>160
>100
Hypertension
