
ABOUT BLOOD PRESSURE
What is blood pressure?
The heart creates a force as it pushes blood into the arteries and through the
blood circulation system. The arteries create another force as they resist the
blood flow. Blood pressure is the result of these two forces.
What constitutes high blood pressure?
JNC7 Classification Table
Range
Stage 2 Hypertension
Stage 1 Hypertension
Prehypertension
Normal
SOURCE: The Seventh Report of the Joint National Committee on
Prevention, Evaluation and Treatment of High Blood Pressure for Adults.
National Heart, Lung and Blood Institute - may 2003.
Stage 3 Hypertension
Stage 2 Hypertension
Stage 1 Hypertension
High-Normal
Normal
Optimal
SOURCE: Standards to assess high blood pressure, without regard to age or
gender, have been established by the World Health Organization (WHO).
Systolic
140-159 mmHg
Systolic
Diastolic
≧
160 mmHg
≧
100 mmHg
120-139 mmHg
80-89 mmHg
< 120 mmHg
< 80 mmHg
WHO Classification Table - for adults outside of the U.S. (e.g. Canada, mexico)
Range
Diastolic
160-179 mmHg
According to the Joint National Committee 7 (JNC 7) definitions, when systolic blood
pressure exceeds 140 mmHg or diastolic blood pressure exceeds 90 mmHg, this
constitutes high blood pressure (see figure below)
90-99 mmHg
90-99 mmHg
100-109 mmHg
< 130 mmHg
< 85 mmHg
≧
180 mmHg
≧
110 mmHg
130-139 mmHg
85-89 mmHg
140-159 mmHg
< 120 mmHg
< 80 mmHg
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