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CFS and Autonomic Dysfunction


By Craig Maupin at

When you flip a light switch on in your house, you know what the end-result will be. The light switch connects a circuit that produces light when the electrons reach the filament. Your computer is similar. While you type a report or surf the Internet, the computer performs an abundance of unseen tasks in the background: checking for printer signals, moving data to the hard drive, and organizing its memory.   It is easy to take these tasks for granted, because they operate behind the scenes; they don’t seem relevant to the task at hand.

The human body functions much the same way. Every process in the body is controlled by signals sent from the brain, through the nerves, to each individual organ or muscle. Like the example of our computer, there is an abundance of tasks the body performs that can be easily taken for granted.    These background tasks are referred to as the “autonomic nervous system”.    Heart rate, sleep, digestion, and vascular pressure are all normal bodily functions that don’t receive a second thought.    But, what if the body didn’t perform these functions correctly?   What does autonomic nervous system dysfunction feel like?

There are a few illnesses that cause autonomic nervous system dysfunction.   As if by design, the areas of the brain controlling the autonomic nervous system were made the most secure. Even in degenerative neurological diseases such as Alzheimer’s or Parkinson’s, autonomic functions like heart rate and digestion remain untouched until the late stages of the illness.

However, there are examples of illnesses that do wreak havoc on the autonomic nervous system.   In the later stages of diabetes, the nervous system slowly deteriorates from the systemic, long-term damage caused by the illness.   Digestion, heart rate and syncope, pain response, and even sleep can be impaired.   In diabetes, the damage may present itself differently from person to person. This is also true of chronic fatigue syndrome (CFS). But with chronic fatigue syndrome (CFS), the severity of autonomic dysfunction puts the illness in a unique class.

Sleep dysfunction

Each of us has a circadian clock. Most of us take this clock for granted. We simply get sleepy at a certain time each day. We feel refreshed when we wake. With CFS, many lose the ability to sleep regularly.   One person with CFS, Jodi Bassett, explains:  “You can lie awake with insomnia all night, completely exhausted but unable to sleep."

Sleep deprivation is not the cause of the fatigue of chronic fatigue syndrome (CFS). When patients are able to sleep, often they find they are not refreshed.   They wake feeling just as tired as they did when they retired for the night.   Many theorize that the lack of restful sleep seen in CFS is caused by metabolic or circulatory dysfunction in the illness.   Gerry Campbell, who worked in biomedical research before being disabled by CFS, says sleep in CFS doesn’t mean a respite from the illness, “The fatigue is not relieved with either rest or sleep.”

Orthostatic Intolerance and Tachycardia

Orthostatic intolerance refers to the inability to sit or stand for prolonged periods. The orthostatic intolerance seen in chronic fatigue syndrome (CFS) may or may not be due to autonomic nervous system dysfunction that regulates heartrate. Studies have shown impairment in the circulatory system of CFS. There is a possibility that the makeup of blood in patients with CFS is different.   Many researchers have pointed to a hematological or cardiocirculatory rationale as a possible explanation. 

Peter Rowe, a researcher from Johns Hopkins, was one of the first researchers to elucidate the strong link between chronic fatigue syndrome (CFS) and orthostatic intolerance. According to Rowe, the problem is widespread in the illness, but poorly understood, "We have no good data on the true prevalence of the problem.   I follow over 400 adolescents with orthostatic intolerance in association with chronic fatigue syndrome."

Many patients suffer from postural tachycardia, a faster than normal heartbeat upon standing or remaining upright for a short time.   Donna, who is from Arizona, experiences faintness and an increased heart rate after standing or being upright for a short time.    She says CFS “makes it very hard to stand up without feeling terribly weak, faint, and very ill. My pulse races to 140.”    Like many people who suffer from CFS, Donna often must remain supine to remain comfortable.    She finds that this makes it difficult for her to leave her house or a couch.

Nausea, pain response, balance, vertigo

Balance and vertigo are also common. Laura Hillenbrand, the author of Seabiscuit, has vividly described what it is like to suffer from this symptom. While writing her bestselling book, she found the text on a page was hard to focus, the room was spinning, and her balance and surroundings were in a constant state of flux. “In the early 1990s, I could not read or write (because of vertigo). There were months when I couldn't get down the stairs. I simply lay in bed and hung a watch on the windowsill and watched the time go by."

Another patient says, “The room can spin with constant vertigo. It can leave you unable to read even a few lines of text, write, watch TV, or have the radio on. ”

Mental Exhaustion

Many people with chronic fatigue syndrome (CFS) find that their memory and cognitive abilities relapse along with their energy levels.   Mental work produces extreme exhaustion.   After using their energy resources on an activity, reading or comprehending written material can be more difficult. Bev, from Alberta, Canada, describes it this way, “…on a really tired day I can read the same thing three times and not know what I read.”

Teresa was on her way to a doctorate fellowship before being felled by CFS.    She describes what it is like to lose her ability to process information quickly.   “I cannot balance my checkbook.   I used to balance it every month.    Heavy traffic is scary, it is overwhelming.”

Johnny Bohn, who has struggled with chronic fatigue syndrome (CFS) while completing his doctorate for close to 20 years, has found that working with the neurological dysfunction of CFS exacts a toll on his ability to remember details. “Long term [memory] is unaffected, but my short term is almost completely gone. I can't remember things from one minute to the next.    Reading comprehension is terrible.   I have to read things many times before I start to remember, and then read them again later to be somewhat reminded.”

The most striking thing about chronic fatigue syndrome (CFS) is that some activities that are taken for granted can become difficult under CFS.    Carole Anne Dumas, who was a graphic artist before becoming disabled 3 years ago, describes losing one of her most pleasurable activities, reading: “I have been unable to read a book for the past 8 years, truly a heartbreaking and unexpected loss. Reading is always a sickening and painful effort; this lifelong pleasure, once taken for granted, is now an elusive luxury.”

This experience is common. Jerry Campbell says the mental clarity is most severe after exercise:   “I also have a next-day energy crash, with very deep fatigue and energy so low that it affects my thinking and memory.   All symptoms get worse after exercise. An hour or less of heavy exertion, or a few hours of moderate exertion, cause all symptoms to become severe, including memory, mental ability, listening, word-finding, balance and body temp, in addition to the pain and fatigue.”    Because of these problems, many people with CFS feel neuro-processing problems in CFS are not neurological at all, but may have metabolic roots.   Recent and powerful Rna profiling studies done by the CDC have had more metabolic and immunological hits than neuroendocrine dysfunction.

A Common Factor

In coming years, there may be considerable debate over the source of the neurological dysfunction of chronic fatigue syndrome (CFS).   Neurology, more than other medical disciplines, often walks a fine line between theory and concrete knowledge. Some believe that each neurological symptom could be explained by the cardiologic and hypovolemic research. However, the question yet to be answered is whether the cardiological implications in CFS are due to autonomic dysfunction, or vice versa.    Others believe tissue inflammation or metabolic dysfunction is a likely culprit.

Either way, living with chronic fatigue syndrome (CFS) is like living with a body that cannot perform the tasks needed to keep its house in order.  Cognitive exhaustion, vertigo, balance problems, and memory may all be affected by CFS. Autonomic dysfunction, whatever the cause, can be a disabling and life-altering symptom of CFS.


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