Chronic Fatigue Syndrome (CFS), ME and Fatigue By Cort Johnson
The Fatigue in Chronic Fatigue Syndrome: CFS patients have never been happy about the word ‘fatigue’ in CFS and they well recognize the dangers of focusing too much on it; they have dealt with them for almost 20 years in the US. Fatigue is certainly present in enormous amounts in most CFS patients but it’s the post exertional malaise – the inability to engage in activity without increased symptoms- that’s the core symptom for many CFS patients. While CFS patients and advocates have come to rue the prominence fatigue has come to play in the perception of their disease no efforts have been made to completely dissociate themselves from it.
The Fatigue in ME: Some ME advocates on the other hand flatly deny fatigue is present at all in ME. One prominent website flatly states “Myalgic encephalomyelitis has nothing to do with fatigue” and that “If you are tired all the time you do not have ME’. This website also claims that fatigue was not associated with ME until 1988 when ‘CFS’ came along. An Flawed Definition?
Indeed, fatigue plays only a negative role in the latest (2007) ME definition put forth by Dr. Hyde. Besides the elucidation of a ‘disease process’ in ME the presence of fatigue in CFS appears to be a major differentiating factor between the two diseases. CFS Except for fatigue the symptoms of ME are startlingly similar to those of CFS. They include pain, cognitive deficits, sleep problems, muscle pain, loss of muscle strength after exercise (post-exertional malaise) and vascular problems (problems standing, abdominal problems).
One could easily be forgiven for assuming, based on that list, that Dr. Hyde was referring to CFS not ME. But he’s clearly not for not long afterwards he bluntly states ‘ME is not CFS’ . Why? Because “fatigue was never a major diagnostic criteria of ME”. Dr. Hyde reports that ‘fatigue, loss of stamina, failure to recover quickly occur…in most if not all progressive terminal disease and in a very large number of chronic non-progressive or slowly progressive diseases’. “Fatigue and loss of stamina…cannot be seriously measured…and do not assist us with the diagnosis of ME or CFS or for that matter any disease process”
According to the ME definition the ME patient is in pain, has cognitive problems, often has problems standing but does not suffer from substantial fatigue or if they do, it is of little consequence to the physician or researcher.
Loss of muscle strength after exercise probably refers to weakness not fatigue. Dr Chaudhury and Behan carefully distinguished between weakness and the fatigue when they described the features of ‘central fatigue’ a problem they they believe is a central feature of CFS. If ME patients are weak rather than fatigued they can be thankful; weakness itself is not uncomfortable, fatigue on the other has a high misery index.
A Historical Perspective: Are ME patients weak or fatigued or both? An examination of the early (and virtually only) studies on ME indicates that far from being a throw away symptom fatigue is often mentioned by the early ME researchers. In 1959 Dr. Acheson, in a large overview of these studies, summarized what was known about ME. Dr Acheson noted, as Dr. Hyde does, that the severe headaches, muscle pains (and paralysis!?) are often seen early in the disease. In fact fatigue is not always mentioned although several analogues to it (lassisitude, lethary) often are. Dr. Acheson notes, as does Dr. Hyde that the severe headaches and muscle pain in ME tend to diminish over time.
What Dr. Hyde does not report, however, is that follow up studies invariably mention that severe fatigue is a debilitating part of the disorder. In the Coventry outbreak the authors reported that ‘extreme fatigue… made the rehabilitation period extremely tedious and long’. Dr. Acheson reported that the ‘majority of patients afflicted in the outbreaks…have returned to work after a period of convalescence prolonged by fatigue, aches and pains, depression and lack of concentration”. Seven to ten months after the Akureyri outbreak ‘nervousness, fatigue and persistent muscle pains were common. Six years later those still afflicted complained of ‘nervousness and tiredness’ and less commonly muscle pain and loss of memory. Five months after the Punta Gorda outbreak the still ill patients most commonly complained of ‘nervous tensions, fatigue and depression.’ Two years afterwards Deischer reported the most common problems were ‘tiring easily’ followed by pain and stiffness.
In Dr. Ramsey’s and Dorsett’s 1977 letter to the British Medical Journal on ME they stated that the most characteristic presentation is profound fatigue…increasing in severity with exercise. (Interestingly these five doctors do not mention headache). A letter to the BMJ on epidemic myalgic encephalomyelitis on June 3rd ,1978 states ‘One characteristic feature of the disease is exhaustion, any effort producing generalized fatigue”. In Dr. Acheson’s summary he states that ‘in some instances a characteristic syndrome of chronic ill health has developed with cyclical redrudescences of pain, fatigue, weakness and depression…”
In the more modern era the first symptom that Dr. Ryll, a U.S. physician who has conducted the longest continual study of ME patients on record (1975-1994), listed was severe exhaustion. He noted that the ‘exhaustion that occurs in this disease is profound and unusual”. (Although championed by ME advocates for many years Dr. Ryll believes ME, CFS, fibromyalgia and gulf war syndrome are essentially the same disorder). ME advocates often claim the Incline Village outbreak of 1983-85 to be ME yet Drs. Cheney, Komaroff, Peterson, Buchwald, etc. required that patients experience ‘chronic debilitating fatigue’ for at least 3 months in order to participate in the study. Dr. Ramsey in 1986 twice referred to the ‘dominant clinical feature of profound fatigue’ in ME. The Ramsey and Dorsett ME criteria (1990) stated that the first cardinal feature of ME is ‘Generalized or localized muscle fatigue after minimal exertion with prolonged recovery time’.
Thus long before some ME advocates sought to distance themselves from the fatigue in ‘CFS’ ME physicians and researchers were consistently reporting that fatigue was a significant problem at least in the chronic stage of the disease.
An Unusual and Medically Significant Degree of Fatigue in CFS – While fatigue is difficult to measure it is incorrect that to state that its presence does not assist physicians in the diagnosis of any disease process. Even the International (CDC) Definition takes pains to emphasize the unusual severity of the fatigue seen in CFS calling it’severe disabling fatigue’ and stating that “in our conception of the chronic fatigue syndrome, the symptom of fatigue refers to severe mental and physical exhaustion, which differs from somnolence or lack of motivation”. Studies indicate high disability rates and extremely low quality of life rankings. CFS – as most ME advocates well know – is not mere fatigue.
A Significant Clinical Feature – Fatigue occurs in many diseases but few diseases display the kind (both physical and mental) or the level of fatigue or exhaustion found in CFS. Far from being a throw away symptom severe and incapacitating fatigue is unusual enough to draw the attention of increasing numbers of researchers. Dr. Friedman reported significant increases in the number of studies focused on fatigue had occurred in the last five years at the 2007 IACFS Conference. Diseases and disorders such as multiple sclerosis, cholestatic liver disease, post-cancer disorder and fibromyalgia are characterized by fatigue severe enough to be the subject of study. All can be initiated by an infectious event and research suggests immune/central nervous system dysfunction play an important role in each. Interestingly study findings in all these diseases are generally coherent with those found in CFS and therefore, since ME findings borrow extensively from CFS research studies, on ME as well.
No one likes the word ‘fatigue’ – as noted earlier it obscures the post-exertional problems that are characteristic of CFS/ME and CFS and both ME and CFS advocates would do well, I believe, to continue to highlight that difference. To ignore that fatigue is present in ME, however, is to turn ones back on the fifty years of ME research and much interesting research today into the cause of severe fatigue. ME advocates attempts to distance themselves from the crude stamp of fatigue are easily understood but turning their backs on an important part of their own disease is unwise and using fatigue as a hammer to divide CFS patients in the US from ME patients elsewhere is not only incorrect but is surely unproductive at a time when ME/CFS or if you like ME and CFS face so many obstacles.
Buchwald, D., Cheney, P., Peterson, D., Henry, B., Wormsley, S., Geiger, A., Ablashi, etc. 1992. A chronic illness characterized by fatigue, neurologic and immunologic disorders, and active Human Herpesvirus Type 6 Infection. Annals of Internal Medicine 1116: 103-13.
Chaudhuri, A. and P. Behan. 2000a. Fatigue and basal ganglia. Journal of Neurological Sciences 179: 34-42.
Chaudhuri, A. and P. Behan. 2000b. Neurological dysfunction in Chronic Fatigue Syndrome. Journal of Chronic Fatigue Syndrome 6, 51-68.
Chaudhuri, A. and P. Behan. 2004b. Fatigue in neurological disorders. Lancet 363: 978-988. Epidemic myalgic encephalomyelitis. 1978. British Medical Journal 3, June 1978, 1436.
Ramsey, M. 1986. Myalgic Encephalomyelitis: A baffling syndrome with a tragic aftermath.
Ramsey, A., Dowsett, E., Dadswell, J., Lyle, W., Parish, J. 1977. Icelandic disease (benign myalgic encephalomyelitis or Royal Free disease. British Medical Journal 298, 1350.
Ryll, E. 1994. Infectious venulitis, chronic fatigue syndrome and myalgic encephalomyelitis.