Diagnostic Criteria for Hypertension

Primary Diagnostic Threshold

The International Society of Hypertension defines hypertension as blood pressure ≥140/90 mm Hg 1
Hypertension is diagnosed when systolic blood pressure is ≥140 mm Hg and/or diastolic blood pressure is ≥90 mm Hg on repeated office measurements, typically requiring 2-3 visits at 1-4 week intervals to confirm the diagnosis 1

The American College of Cardiology recommends that patients sit quietly for 3-5 minutes before measurement in a comfortable temperature room 1
Patients should not smoke, consume caffeine, or exercise for 30 minutes prior to measurement, and should have an empty bladder 1
The arm should be supported at heart level on a table, with the back supported, legs uncrossed, and feet flat on the floor 1
A validated electronic upper-arm cuff device with an appropriate cuff size should be used 1
Three measurements should be taken with 1 minute between them, and the last two readings should be averaged 1

The International Society of Hypertension recommends using home or ambulatory blood pressure monitoring to confirm the diagnosis whenever possible 1
White coat hypertension is defined as office blood pressure ≥130/80 mm Hg but out-of-office blood pressure <130/80 mm Hg 2
Masked hypertension is defined as normal office blood pressure but elevated out-of-office blood pressure 2

Common errors that bias readings upward and lead to over-diagnosis include incorrect arm position, wrong cuff size, talking during measurement, unsupported back or feet, full bladder, and recent caffeine, smoking, or exercise 1, 2

The American College of Cardiology recommends that elderly patients (≥65 years) be diagnosed using the same criteria as younger patients (≥140/90 mm Hg by international standards or ≥130/80 mm Hg by ACC/AHA) 2
Patients with diabetes should be diagnosed using the same threshold as the general population (≥130/80 mm Hg by ACC/AHA criteria) 2

Stage 1 hypertension (130-139/80-89 mm Hg by ACC/AHA criteria) carries approximately 2-fold increased cardiovascular disease risk compared to normal blood pressure 2