What Is the Danger Zone for High Blood Pressure?

Ask a Doctor

I just went to my cardiologist and he said my blood pressure was too high – 138/87. She put me on an ACE inhibitor called Capoten and told me I needed to change my diet, cut out salt and exercise if I wanted to keep my hypertension out of the “danger zone.” What is the danger zone for high blood pressure? What do the numbers mean?

Doctor's Response

Based on the your blood pressure numbers, you have stage 1 hypertension. I’m glad you’re getting the treatment you need. Please heed your doctor’s advice about diet and exercise, because the more quickly you can reduce your blood pressure, the less the risk of developing a host of other complications.

Uncontrolled high blood pressure is responsible for many cases of death and disability resulting from heart attack, stroke, and kidney failure. According to research studies, the risk of dying of a heart attack is directly linked to high blood pressure, particularly systolic hypertension. The higher your blood pressure, the higher the risk. Maintaining lifelong control of hypertension decreases the future risk of complications such as heart attack and stroke.

Blood pressure is measured with a blood pressure cuff and recorded as two numbers, for example, 120/80 mm Hg (millimeters of mercury). Blood pressure measurements are usually taken at the upper arm over the brachial artery.

  • The top, larger number is called the systolic pressure. This measures the pressure generated when the heart contracts (pumps). It reflects the pressure of the blood against arterial walls.
  • The bottom, smaller number is called the diastolic pressure. This reflects the pressure in the arteries while the heart is filling and resting between heartbeats.

The American Heart Association and the American College of Cardiology has recommended guidelines to define normal and high blood pressure (all values are in mm Hg).

  • Normal blood pressure: Systolic < 120 and diastolic < 80
  • Elevated blood pressure: Systolic 120-129 and diastolic < 80
  • Stage 1 hypertension: Systolic 130-139 or diastolic 80-89
  • Stage 2 hypertension: Systolic > 139 or diastolic > 89

Based on these 2017 guidelines defining high blood pressure, as many as half of all Americans will have this disease (48% of men and 43% of women).

References
American Heart Association.

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Hoeper MM, et al. Goal-oriented treatment and combination therapy for pulmonary arterial hypertension; Eur Respir J. 2005 Nov;26(5):858-63.

Lipsitz LA, et al. Antihypertensive therapy increases cerebral blood flow and carotid distensibility in hypertensive elderly subjects; Hypertension. 2005 Feb;45(2):216-21. Epub 2005 Jan 17.

Pischke CR, et al. Comparison of coronary risk factors and quality of life in coronary artery disease patients with versus without diabetes mellitus; Am J Cardiol; 2006 May 1;97(9):1267-73. Epub 2006 Mar 10.

Whelton PK, et al. 2017 High Blood Pressure Clinical Practice Guideline: Executive Summary. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults. Nov 2017.
<http://hyper.ahajournals.org/content/hypertensionaha/early/2017/11/10/HYP.0000000000000066.full.pdf?download=true>

NIH. Description of the DASH Eating Plan. Updated: Sep 16, 2015.
<https://www.nhlbi.nih.gov/health/health-topics/topics/dash>