This information was first published in the May 2000 issue of the Lyndonville Journal - a bi-monthly newsletter from Dr. Bell's medical office that preceded the Lyndonville News (DavidSBell.com). It is reproduced here with kind permission,* and offers basic information on a subject of great current interest, with researchers at various centers(1) working to unravel the link between orthostatic dysfunction and ME/CFS.
Orthostatic Intolerance and Chronic Fatigue Syndrome (ME/CFS)
“In many medical illnesses, the patient will feel ill regardless of whether he or she is lying down or standing up. With CFS, patients will say, ‘"I feel so exhausted I have to lie down.’”
Orthostatic intolerance (OI) is a term used for illnesses which are characterized by inability to maintain the upright posture. It is a group of illnesses that overlaps with CFS just as fibromyalgia does, and it may give up leads as to the underlying pathology of the illness. The most exciting new leads are happening in the world of orthostatic intolerance.
Because much of the literature on OI may be unfamiliar to the reader, I will try to summarize it. For those interested in more in-depth reading, I would start with “The Epidemic of Orthostatic Tachycardia and Orthostatic Intolerance.” The February 1999 issue of the American Journal of the Medical Sciences. This issue [unfortunately fee based] is devoted to a review of OI, and much of what I will say here is taken from that issue.
Defined simply, OI is the presence of symptoms due to inadequate cerebral perfusion [blood flow to the brain] on assuming the upright posture. The usual symptoms include fatigue, nausea, lightheadedness, heart palpitations, sweating, and sometimes passing out.
Many persons with medically proven OI have been assumed to have emotional problems when they don’t.
Like CFS, there have been many terms in the past to describe this group of disorders, including “asthenia.” Sound familiar? It is not known what is the exact relationship between OI and CFS, and up until recently studies in the two areas have followed separate tracks.
The one very nice advantage OI has over CFS is that it can be proven and there are well defined subgroups.
Over the past year in our office we have been testing patients with CFS for OI by two methods.
• One has been a circulating blood volume study [low blood volume is common in ME/CFS],
• And the second is a test for orthostatic intolerance. This test is easily done in the office and requires only a blood pressure cuff and a good nurse to catch the patient before passing out.
The test is relatively simple.
• The patient lies comfortably for ten minutes and BP and pulse are taken several times.
• Then the patient stands quietly (no moving around) with the blood pressure cuff on, and BP and pulse are taken every few minutes.
This is a poor man’s tilt test [tilt test video], and I would argue that it is more accurate because it reproduces exactly what happens to a patient waiting in the checkout line at the supermarket. [For detail, see sidebar on "Orthostatic Testing Procedure."]
A person with CFS nearly always has orthostatic intolerance.
They describe the symptom of fatigue (which is not fatigue at all), which is characterized by being relatively OK while walking down the aisle of the supermarket, but being unable to stand in the checkout line. The orthostatic testing describes physiologically why this occurs.
There are five separate abnormalities than can occur during quiet standing:
1. Orthostatic Systolic Hypotension
Where the upper number (systolic) blood pressure drops. The normal person will not drop BP more than 20mmHg on standing up.
One patient I follow with CFS had a normal BP lying down (100/60) but it fell to 60/0 on standing. No wonder she was unable to stand up – a blood pressure that low is really unable to circulate blood to the brain. In any ICU they would panic seeing a BP like that. And she was turned down for disability because she probably was a hypochondriac.
2. POTS - Stands for Postural Orthostatic Tachycardia Syndrome
A healthy person will not change their heart rate standing up for an hour.
In a person with POTS, this heart rate increases 26 beats per minute (bpm). Some experts say the heart rate should exceed 120 bpm to have POTS. But either way, this increase occurs frequently in CFS.
I think the increase in heart rate is linked to the decrease in blood volume. Orthostatic intolerance has been called idiopathic hypovolemia [low blood volume] in the past.)
3. Orthostatic Narrowing of the Pulse Pressure
The pulse pressure is the difference between the upper number of the BP and the lower number. For example, a normal person with a BP of 100/60 would have a pulse pressure of 40.
It is actually the difference between the upper (systolic, maximum pressure) and lower number (diastolic, minimum pressure) of the BP that circulates blood.
• If the pulse pressure drops below 18, it is abnormal, and blood would not circulate in the brain well.
• We routinely see in our patients with CFS blood pressures of 90/80, thus a pulse pressure of 10.
• The current record holder is a young woman with CFS whose pulse pressure fell to 6 mmHg before she passed out.
4. Orthostatic Diastolic Hypertension
The lower number of the BP often reflects the systemic resistance, and while standing, many persons with OI and CFS will raise their lower BP number in [the body's] attempt to push blood up to the brain.
Sometimes this is dramatic. One patient being followed with CFS has a low blood volume, about 60% of normal. While lying down, his BP was 140/80. After standing, his BP rose to 210/140 before we made him lie down. His pulse went up to 140 bpm. He felt rotten but refused to sit down by himself.
As an aside, everyone thought he was a fruitcake – a healthy looking man who said he felt poorly and couldn’t work. He was denied disability as usual. Yet when we did the test, he was so determined to stand up I was afraid… But he was standing with a BP of 210/140 and a pulse of 140 bpm. He is definitely not a wimp.
After the test, we gave him a liter of saline in the office because he didn’t look too good and his blood pressure fell to 90/80 after an hour or so.
It is important to note that we had measured his volume the day before so we knew he was hypovolemic [had low blood volume]. Normally you would never give saline to someone with high blood pressure, it just makes it go higher. In the future, orthostatic testing will require being done in an intensive care unit because these number are so scary.
Now it is ignored, and patients with CFS called fruitcakes!
5. Orthostatic Diastolic Hypotension
This represents a fall in the lower number of the BP, and seems to be the least frequent abnormality in patients with CFS I have tested.
[To learn more, read "Maggie's Panic" - Dr. Bell's intriguing case study of a CFS and fibromyalgia patient whose 'strange symptoms' were finally diagnosed as orthostatic intolerance and low blood volume.]
Below is a listing of these BP abnormalities and normal values, taken from Dr. David Streeten’s book Orthostatic Disorders of the Circulation.... These are important as they will directly measure treatment responses with something other than symptom improvement.
NORMAL systolic blood pressure (sBP) - upper number:
Standing (4 min): 94-141;
Orthostatic change -19 to +11
NORMAL diastolic blood pressure (dBP) - lower number:
Orthostatic change: -9 to +22
Orthostatic Systolic Hypotension:
Fall in systolic blood pressure of 20mmHg or more
Orthostatic Diastolic Hypertension:
Fall in diastolic BP of 10 mmHg or more
Orthostatic Diastolic Hypertension:
Rise in diastolic BP to 98 mmHg or higher
Orthostatic Narrowing of Pulse Pressure:
Fall in pulse pressure to 18 mmHg or lower
Orthostatic Postural Tachycardia:
Increase in heart rate of 28 bpm, or to greater than 110 b/min
Jean Pollard, Dr. Bell's office manager, adds:
In our office we see a number of patients for assessment of disability..... [One part of such an evaluation is a Summary of Laboratory Evaluation.] Supportive laboratory evaluation such as orthostatic testing, circulating blood volume or immunologic status should be reported along with negative studies. Supportive laboratory evaluation should be referenced to show that it has been noted to occur in CFS. For example:
Orthostatic testing revealed orthostatic tachycardia with an elevation of pulse on quiet standing of 47 beats per minute.(1,2)
(1) DeLorenzo F, Hargreaves J, Kakkar VV. Possible relationship between Chronic Fatigue Syndrome and postural tachcardia syndromes. Clin Auton Res 1996 6(5);263-4
(2) Jacob G, Biaggioni I. Idiopathic orthostatic intolerance and postural tachycardia syndrome. Am J Med Sci 1999; 317:88-101.
Orthostatic Testing Procedure
- David S Bell
A number of people have requested the procedure for orthostatic testing that we perform in the office. It takes about 45 minutes and requires a nurse to be constantly present. It is important to note that this test is difficult for some persons with CFS, and an opportunity to rest for an hour after the testing is offered. Intravenous saline is helpful to aid recovery.
1. Patients should be tested late morning or early afternoon with no unusual activity prior to testing. Large meals and large volumes of fluid prior to testing should be avoided.
2. Normal medications should be taken the day of the test. Medications which affect circulating volume should be stopped at least two weeks prior to testing, as they will affect the results. Examples are Florinef, diuretics, blood pressure medications, large salt loads. Tricyclics and SSRI medications are acceptable if not for research studies.
3. Blood pressure should be taken with manual blood pressure cuff every three to five minutes, along with pulse. If available, a dynamap or other accurate BP device can be used.
4. Step 1. Patient lying down comfortably for 10 minutes. Pulse and BP are recorded at onset, 5 minutes and 10 minutes. Pulse and BP are recorded at onset, 5 minutes and 10 minutes, along with recording of observations of spontaneously reported symptoms.
5. Step 2. Patient stands without moving or leaning on any object for 30 minutes or as long as tolerated. If patient pre-syncopal (feeling about to faint), the test is terminated. Right arm is resting on table at mid chest (heart) level with BP cuff in place. Pulse and BP are taken every 5 minutes, and spontaneous symptoms recorded as well as observations (e.g., yawning, feet mottled or bluish, etc). If symptoms become more severe, pulse and BP are taken every 3 minutes.
In recording results, use the listing of normal values and abnormalities per Dr. David Streeten, provided above.
* Reproduced with kind permission of the author from the paper archives of the Lyndonville Journal, © Bell, Pollard, Robinson, 2000. All rights reserved.
1. Other Resources. For recent research reports, see also:
• "Pulse abnormalities at rest and during tilt test could be highly indicative screen for ME/CFS" - Newcastle University
• "Fibromyalgia-like pain as a cause of autonomic dysregulation," (animal study data "corroborate findings in humans with FM.) - University of Iowa.
• "Postural Orthostatic Tachycardia Syndrome following Lyme Disease" - University of Toledo Medical Center
• "Orthostatic symptoms predict functional capacity in chronic fatigue syndrome: Implications for management," - Newcastle University
• "Orthostatic Stress Impairs Cognitive Function in CFS with POTS," - New York Medical College
• "Blood pressure testing should routinely check for orthostatic hypotension too, researchers advise," - Rosalind Franklin University of Medicine & Science, Chicago
Note: This information has not been evaluated by the FDA. It represents the personal research and opinions of the authors, is for general informational purposes only, and is not meant to prevent, diagnose, treat or cure any condition, illness, or disease. ME/CFS/FM is an extremely complex illness, and advice in a newsletter may not be appropriate for a specific individual. Therefore, should you be interested or wish to pursue any of the ideas presented here, please discuss them with your personal physician.