Hypertension
Longxian Cheng
Department of Cardiology, Union Hospital
Tongji Medical College, HUST, Wuhan
Introduction
Hypertension is a major public health problem throughout the world because of its high prevalence and its association with increased risk of cardiovascular disease.
Approximately 100 million Chinese have elevated BP. Of these, 77% are aware of their diagnosis, 70% are receiving treatment, and only 33% are under control.
Definition
Hypertension is defined as a SBP of 140 mmHg or greater and/or a DBP of 90 mmHg or greater in subjects who are not taking antihypertensive medication.
Essential or primary hypertension is a hypertension of unknown cause.
Isolated systolic hypertension is defined as SBP of 140 mmHg or greater and diastolic BP less than 90 mmHg.
Classification of Blood Pressure Levels (mmHg)
Category Systolic Diastolic
Optimal <120 <80
Normal <130 <85
High-normal 130-139 85-89
Grade 1 hypertension(mild) 140-159 90-99
Subgroup: borderline 140-149 90-94
Grade 2 hypertension(moderate) 160-179 100-109
Grade 3 hypertension(severe) ≥180 ≥110
Isolated systolic hypertension ≥140 <90
Subgroup: borderline 140-149 <90
Notes
1. When a patient’s SBP and DBP fall into different categories, the higher category should apply.
e.g.
154/100 mmHg is defined as grade 2 hypertension.
180/82 mmHg is defined as grade 3 isolated systolic hypertension.
Notes(Continue)
2. BP is based on the average of two or more readings taken at each of two or more visits after an initial screening(筛查).
e.g.
12/2 first visit: 172/102 mmHg, 168/104 mmHg.
13/2 second visit: 158/98 mmHg, 158/96mmHg.
The average BP is 164/100 mmHg, which is defined as grade 2 hypertension.
Notes(continue)
3. The patient should be clearly informed that a single elevated reading does not constitute a diagnosis of hypertension but is a sign that further observation is required.
For instance:
21/3 1st visit: 146/98mmHg, 150/98mmHg
23/3 2nd visit: 128/84, 126/80
27/3 3rd visit: 130/80, 130/82
Notes(continue)
4. Optimal BP with respect to cardiovascular risk is less than 120/80 mmHg. However, unusually low readings should be evaluated for clinical significance.
For example,
70/50 mmHg is less than 120/80 mmHg, but it is not optimal.
Classification of Blood Pressure Levels (mmHg)
Category Systolic Diastolic
Hypotension??? <90 <60
Optimal <120 <80
Normal <130 <85
High-normal 130-139 85-89
Grade 1 hypertension(mild) 140-159 90-99
Subgroup: borderline 140-149 90-94
Grade 2 hypertension(moderate) 160-179 100-109
Grade 3 hypertension(severe) ≥180 ≥110
Isolated systolic hypertension ≥140