From the Guidelines
A positive orthostatic blood pressure response indicates orthostatic hypotension, which is characterized by a decrease in systolic blood pressure of at least 20 mmHg or a decrease in diastolic blood pressure of at least 10 mmHg within three minutes of standing, as defined in the most recent and highest quality study 1. This condition results from the body's inability to adequately adjust blood pressure when changing positions, often due to inadequate vasoconstriction or impaired autonomic nervous system function. Common causes include:
- Dehydration
- Certain medications (particularly antihypertensives, antidepressants, and diuretics)
- Neurological disorders like Parkinson's disease
- Endocrine disorders
- Prolonged bed rest
- Aging Symptoms may include:
- Lightheadedness
- Dizziness
- Blurred vision
- Weakness
- Fatigue
- Fainting upon standing Management typically involves addressing underlying causes, ensuring adequate hydration, rising slowly from lying or sitting positions, wearing compression stockings, increasing salt intake if appropriate, and in some cases, medications like fludrocortisone or midodrine may be prescribed to help maintain blood pressure, as suggested by 1. It's worth noting that the definition of orthostatic hypotension has been consistently defined across various studies, including 1, 1, and 1, but the most recent and highest quality study 1 provides the most up-to-date guidance on this condition.
From the Research
Orthostatic Blood Pressure Response
A positive orthostatic blood pressure response is indicated by an increase in blood pressure upon standing from a supine position. This response is a normal physiological reaction to maintain blood flow to the brain and other organs when changing posture.
Indications of Positive Orthostatic Response
- An increase in systolic blood pressure of 20 mmHg or more upon standing is considered a positive orthostatic response 2
- This response is associated with an increase in heart rate to maintain blood pressure upon standing 2
- A positive orthostatic response is not necessarily associated with an increased risk of cardiovascular disease, unlike standing hypertension 3
Comparison with Orthostatic Hypotension
- Orthostatic hypotension is a decrease in blood pressure upon standing, which can lead to impaired blood supply to the brain and other organs 4, 5
- Orthostatic hypotension is associated with an increased risk of adverse outcomes such as syncope, falls, and mortality 6
- A positive orthostatic response is distinct from orthostatic hypotension and is not typically associated with these adverse outcomes