Part 3: Is it POTS? POTS vs. OH
Updated: Dec 27, 2022
This page is Part 3 of a 4-part series
Part 2: Is it POTS? Autonomic mimics Part 3: Is it POTS? POTS vs. OH
Postural orthostatic tachycardia syndrome (POTS) and orthostatic hypotension (OH) can look a lot alike. They both cause rapid heart rate (hr) and lightheadedness with prolonged standing. Management of POTS and OH is similar. Medication options overlap, but there are differences. While POTS is common in Sjogren’s, it is important to rule out mimics, as reviewed in Part 1 and Part 2 of this blog series.
On Sjogren’s Advocate, OH refers to a long-term difficulty maintaining blood pressure when upright because of a malfunctioning autonomic nervous system Clinicians often associate OH with the acute version that is seen with dehydration, blood loss, etc. It is important to explain the chronic nature of your symptoms to your clinician.
Standing test – It is useful to document readings from two or more home standing tests before your medical appointment. Readings that support a POTS or OH diagnosis should prompt further investigation. The standing test should be repeated in the clinic setting for confirmation and documentation. See Part 2 of this blog series for the diagnostic criteria for POTS and OH. Take these to your clinic appointment:
Your standing test results The standing test handout and article recommended on the POTS page This article about OH
Even if your clinician is familiar with POTS and OH it is good to have articles on hand for self-advocacy. See the Clinician Handouts for tips about sharing articles and handouts with clinicians.
The standing test handout is for POTS. Does it work for OH?
Yes, the instructions are the same, with additional readings needed to properly document OH.
If you are doing this on your own, I recommend starting with the standing test for POTS first. If your blood pressure (bp) falls more than 10 mm systolic or 5 mm diastolic at the 2-minute mark, take a break and start over with the standing test for OH. This is the same test but requires additional early readings.
The standing test for OH
Use the standing test for POTS. Record readings at 1, 2, 3, 5, and 10 minutes (vs. 2, 5, 10 minutes.)
If your blood pressure (bp) drops more than 20 mm systolic (top number) or 10 mm diastolic (bottom number) at 3 minutes, this indicates OH, rather than POTs. It is best to complete the 10-minute test unless you feel like fainting.
Why not add the extra readings for OH at the outset? This should be fine if you have someone helping you. Even small movements, such as looking at the blood pressure monitor or recording your result, reduce the accuracy of the test.
Voice recording apps are also a good option.
For both OH and POTS, carefully follow the instructions for the POTS standing test (see link above). Failing to do so reduces test accuracy.
Record the results, including date and time of day, along with any symptoms you have during the test.
Repeat the test on two or three additional days.
POTS and OH screening tests are more likely to be positive first thing in the morning.
What if you have symptoms but your standing test results fall short of the criteria for POTS or OH diagnosis?
One option is to arrange for a Tilt Table test. This eliminates the problem of involuntary leg muscle contraction interfering with test accuracy. This is test is not always readily available. Some people have a classic POTS or OH presentation but do not quite meet the diagnostic criteria. Non-specific orthostatic intolerance is managed similarly to POTS and OH, based on clinical judgment.