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Orthostatic Intolerance and CFS


By Craig Maupin at

There is much in life that we take for granted.   One common, yet necessary, function to live well is remaining upright – sitting and standing.   We must remain upright when we drive a car. We must remain upright when we attend a class.   We must remain upright to watch a movie, attend a wedding, or enjoy a church service.   Most people don’t think twice about it, and many feel these activities are a form of rest.   Yet, orthostatic intolerance (the inability to sit and stand for periods of time) is, for many, the most disabling feature of chronic fatigue syndrome (CFS).   

I remember when I first began to deal with CFS during my senior year of high school. I quickly noticed something was very different when I returned to classes. As soon as I took a seat, it was as if a timer was ticking, and I was on my way to a crash. My legs felt as if they were heavy and disconnected -suffocating.   For simply remaining in my chair, I was paying a heavy and painful price.

Later, I would learn I was not alone. Orthostatic intolerance is one of the most prevalent symptoms of chronic fatigue syndrome (CFS).   It is also one of the most disabling and devastating.   One cannot secure a job without being able to remain seated for any given period of time.   It is difficult to have a social life, attend functions, and participate in social activities.   Life with orthostatic intolerance can seem overwhelming, in a way few understand.

How much it impedes life?

For most people, remaining seated is a restful act that requires no thought.   However, for those with chronic fatigue syndrome (CFS), a restful chair is often far from restful.   Their legs become heavy and exhausted.   If they sit beyond a given period of time, they become exhausted.

Gerald Campbell took a biology degree and parlayed it into a promising career in the pharmaceutical industry, before being derailed by CFS 12 years ago. Like many with chronic fatigue syndrome (CFS), he found standing in one place to be difficult:   “Upon prolonged standing, my legs get tired and achy, and my energy level goes down."  Gerald doesn't have long until he experiences pain:   "The pain and energy drain starts after several minutes.”    Like many with CFS, he finds, “…moving around feels better than standing still.”

Megan, an editor who has had CFS for 10 years, describes the feeling of orthostatic intolerance. “The most difficult is standing in one place (like in a line for more than 5 minutes)… it's a real effort to maintain the standing position and my heart usually starts to race.”

Carole Anne Dumas, a former graphic artist, describes how the simple act of remaining upright can be very uncomfortable:   “ I have blood pooling in hands and feet, blurred vision, heart racing, shortness of breath and a desperate need to sit or lie down when just trying to make up the bed, prepare a simple meal, or even walk to the mailbox. “

Many researchers feel that chronic fatigue syndrome (CFS) is primarily a cardiocirculatory or hematological disease; while other researchers believe the circulatory problems in CFS are secondary to another process, such as immune activation or inflammation.   Whatever the cause, research has found a wide variety of abnormalities in both the cardiocirculatory functioning of CFS patients, as well as the makeup of the blood (see references below).   PWC’s (people with CFS) also have lower cardiac stroke volumes. Many PWC’s also describe feeling thirsty.   One person with CFS says, “I am tremendously thirsty and need to drink water pretty much all day, or at least have it handy.”

What Causes Orthostatic Intolerance and CFS?

Theories as to what causes orthostatic intolerance in CFS differ.   Dr. Peter Rowe, a researcher from Johns Hopkins University, is one of the worlds leading experts on CFS and orthostatic intolerance.   Many of Rowe’s patients come to his clinic carrying a water bottle with them, due to low volume and dehydration.    He has published numerous studies on orthostatic intolerance and low circulating blood volume in CFS.

According to Rowe, “Fully 66% of 171 study subjects with CFS who were screened with a 2-stage upright tilt table test developed neurally mediated hypotension, postural tachycardia syndrome, or both. The evidence for an association between CFS and orthostatic intolerance is strongest in adolescents (constituting Level 1 evidence). In the 9 controlled studies published thus far, 7 have identified a higher prevalence of orthostatic intolerance in CFS patients than in healthy controls. In those with substantial worsening of symptoms during quiet upright posture, orthostatic hypotension can be excluded with a 3 minute standing test. Prolonged orthostatic testing to exclude postural tachycardia syndrome or neurally mediated (vaso-vagal) hypotension may be appropriate in those whose symptoms are aggravated by several minutes of quiet upright posture. “

Theories as to the cause of orthostatic intolerance in chronic fatigue syndrome differ.  Martin Lerner, an infectious disease specialist at Wayne State University, believes CFS is a cardiomyopathy, perhaps caused by immune dysfunction and active infection of the heart muscle .

Les Simpson, a biologist from New Zealand specializing in blood rheology (blood flow), believes that people with CFS may have capillaries that are too small for red blood cells to pass through. “I found that [CFS] blood filtered poorly - implying that they had a problem with blood flow, particularly at capillary level.   In a paper published by New Jersey Medicine, I suggested that [CFS] people might have the anatomical feature of smaller than usual capillary diameters. Such a proposal would help to explain the great variety and variation in distribution of the symptoms reported…”

Red blood cells in CFS have been found to often be misshapen or flattened. This has been theorized to cause the blood to not flow well into the capillaries. Dr. Nancy Klimas at the University of Miami has published studies that the ability of the body to manufacture and restore red blood cells is impaired in those with CFS.

Other researchers feel that the circulatory impairment in chronic fatigue syndrome is caused by neurological impairment caused by a chronic condition.   Diabetes can, over the long term, lead to neurological damage.   Yet, orthostatic intolerance in CFS is often far more severe than that seen in diabetes.   Since many of the symptoms, such as vertigo are present when the patients are supine (lying down), many suggest that the nervous system’s role is secondary.


Whatever the cause, orthostatic intolerance is the most disabling symptom many with chronic fatigue syndrome will face.  Its very presence precludes them from many cherished or productive activities.   Even more troubling, the disabling nature of orthostatic intolerance is difficult for others to understand.   After all, even the most feeble members of society consider sitting in a chair restful, even relaxing.

Yet for those with CFS, the ability to remain upright is not taken for granted.   For many with CFS, taking a seat is anything but restful.


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