Normal blood pressure is widely regarded as 120/80mmHg. A precautionary gap labeled prehypertension for those beyond 120/80mmHg and less than 130/90mmHg existed as well. But in the first update to comprehensive U.S. guidelines on blood pressure detection and treatment since 2003, the category of prehypertension is eliminated.
High blood pressure is now defined as readings of 130 mm Hg and higher for the systolic blood pressure measurement, or readings of 80 and higher for the diastolic measurement. That is a change from the old definition of 140/90 and higher, reflecting complications that can occur at those lower numbers.
This means about 14 percent more people will be diagnosed with high blood pressure and counseled about lifestyle changes. By lowering the definition of high blood pressure, the guidelines recommend earlier intervention to prevent further increases in blood pressure and the complications of hypertension.
Other changes in the new guideline include:
- Only prescribing medication for Stage I hypertension if a patient has already had a cardiovascular event such as a heart attack or stroke, or is at high risk of heart attack or stroke based on age, the presence of diabetes mellitus, chronic kidney disease or calculation of atherosclerotic risk (using the same risk calculator used in evaluating high cholesterol).
- Recognizing that many people will need two or more types of medications to control their blood pressure, and that people may take their pills more consistently if multiple medications are combined into a single pill.
- Identifying socioeconomic status and psychosocial stress as risk factors for high blood pressure that should be considered in a patient’s plan of care.
The new guidelines were developed by the American Heart Association, American College of Cardiology and nine other health professional organizations. They were written by a panel of 21 scientists and health experts who reviewed more than 900 published studies.
Blood pressure categories in the new guideline are:
- Normal: Less than 120/80 mm Hg;
- Elevated: Systolic between 120-129 and diastolic less than 80;
- Stage 1: Systolic between 130-139 or diastolic between 80-89;
- Stage 2: Systolic at least 140 or diastolic at least 90 mm Hg;
- Hypertensive crisis: Systolic over 180 and/or diastolic over 120, with patients needing prompt changes in medication if there are no other indications of problems, or immediate hospitalization if there are signs of organ damage.