What blood pressure readings are considered orthostatic hypotension?

Orthostatic Hypotension Blood Pressure Criteria

Orthostatic hypotension is defined as a sustained decrease in systolic blood pressure of ≥20 mmHg or diastolic blood pressure of ≥10 mmHg within 3 minutes of standing from a supine position. 1, 2

Standard Diagnostic Thresholds

The consensus definition across major cardiology societies establishes clear numerical criteria:

• Systolic BP drop: ≥20 mmHg from baseline 1, 2
• Diastolic BP drop: ≥10 mmHg from baseline 1, 2
• Absolute threshold: Systolic BP falling to <90 mmHg (regardless of the magnitude of drop) 1, 2
• Time frame: Within 3 minutes of active standing or head-up tilt to at least 60 degrees 1, 2

Special consideration: In patients with supine hypertension, a systolic BP drop of ≥30 mmHg should be considered diagnostic. 1, 3

Subtypes Based on Timing

Orthostatic hypotension has distinct temporal patterns that require different measurement approaches:

Initial (Immediate) Orthostatic Hypotension

• Systolic BP drop: >40 mmHg within 15 seconds of standing 1
• Diastolic BP drop: >20 mmHg within 15 seconds of standing 1
• BP spontaneously returns to normal rapidly, with symptoms lasting <40 seconds 1

Classic Orthostatic Hypotension

• Sustained BP decrease meeting standard criteria (≥20/10 mmHg) within 3 minutes 1, 2
• This is the most commonly recognized form 2

Delayed Orthostatic Hypotension

• BP drop meeting standard criteria but occurring beyond 3 minutes of standing 1, 2
• Characterized by slow, progressive decrease in BP 1, 2
• Requires extended standing time beyond the standard 3-minute measurement 3

Proper Measurement Technique

To accurately diagnose orthostatic hypotension, follow this specific protocol:

Baseline measurement:

• Patient rests supine for 5 minutes before initial BP measurement 1, 2, 3
• Use a validated, calibrated BP device with appropriate cuff size for arm circumference 3
• Measure BP in both arms at initial visit; use the arm with higher BP if difference >10 mmHg 3

Standing measurements:

• Measure BP and heart rate at 1 minute after standing 3
• Measure BP and heart rate at 3 minutes after standing 1, 2, 3
• Continue measurements beyond 3 minutes if BP is still falling or if delayed orthostatic hypotension is suspected 1, 3
• Maintain arm at heart level during all measurements 3

Environmental conditions:

• Patient should fast for 3 hours before testing 3
• Avoid nicotine, caffeine, theine, or taurine-containing drinks on test day 3
• Perform testing in temperature-controlled environment (21-23°C) 3

Clinical Pearls and Pitfalls

Continuous vs. interval monitoring: Continuous BP measurement devices are preferred for accurate diagnosis, as interval devices have low concordance with continuous measurements. 3

Heart rate response matters: In neurogenic orthostatic hypotension, the orthostatic heart rate increase is typically blunted (usually <10 beats per minute) due to impaired autonomic control, whereas non-neurogenic causes show compensatory tachycardia. 3

Symptoms vs. numbers: Symptoms depend more on the absolute BP level reached than on the magnitude of the BP fall. 3 This means a patient may be symptomatic even with smaller drops if their baseline BP is lower.

If bedside testing is negative but suspicion remains high: Consider head-up tilt table testing, which can detect orthostatic hypotension missed by standard bedside measurements. 4

Prevalence context: Orthostatic hypotension is present in approximately 10% of all hypertensive adults, up to 50% of older institutionalized adults, and 20% of community-dwelling older adults. 3, 4