Classic ME: the basics

Ellen Goudsmit, PhD, FBPsS, is a psychologist who has long studied ME (myalgic encephalomyelitis) and CFS (chronic fatigue syndrome). She believes that the diagnostic confusion between what are two quite separate conditions is unhelpful both for sufferers and for the understanding of both conditions.

FoodsMatter carries three of her articles on the subject: this one which defines ME; ME or CFS, that is the question which explores the differences between the two conditions, and ME: Chronic Fatigue Syndrome or a distinct clinical entity, a fully referenced academic paper from which the two articles are drawn.

ME usually starts with an infection but unlike a cold or flu, it doesn’t go away. There is a consensus amongst ME specialists that what differentiates ME from the more common post-viral debility (as well as stress, depression and hyperventilation)  are three characteristics:

1. All patients experience rapid fatigue in their muscles after minimal exertion (referred to in medical journals as muscle fatiguability) and there is a delay in the time it takes for those muscles to recover.  Thus if one used to walk for miles without feeling tired, the person with ME  quickly notices increasingly unpleasant symptoms including weakness in the legs, after walking less than a hundred yards.

The second feature, the delayed recovery, is equally important.   If you’re healthy, the muscles begin to recover as soon as you rest but in patients with ME, the loss of strength continues for at least 24 hours. Research using objective measures to test muscle power have demonstrated  this phenomenon in the laboratory. You can see it on a computer. The muscles are weaker and continue to weaken, even  after the patient has stopped exercising and has begun to rest. However, referring to this as fatigue is not only misleading, but is a major reason for the confusion between ME and psychological disorders.

Muscle weakness following minimal exertion is a key symptom and it’s hard to recommend any programme aimed at increasing activity when it’s so often the cause of an exacerbation. It’s like advising a smoker with lung cancer to gradually increase the number of cigarettes they smoke. It makes no sense so why do various doctors recommend it?  Because they don’t believe the growing literature indicating that the symptoms are due to a persistent virus or malfunctioning immune system. That may be accurate if you are seeing people with fatigue due to stress or depression, but not if your patient has post-viral ME.   

2. ME always affects the brain and central nervous system.   It’s not the result of a localised injury which has stabilised. Hence it’s listed under neurological diseases in the International Classification of Diseases (ICD), a tome compiled by the World Health Organisation. ME has been coded in the neurology section  since 1969, following a decision made in 1965. One comparatively trivial sign of ME which patients know well but which is rarely mentioned in medical articles on CFS is the loss of fine motor control. In daily life, this means that someone who used to have very neat handwriting will suddenly find it a real challenge to scribble a legible note to the milkman.

ME also affects other organs and functions. A real give-away symptom is intolerance to alcohol. This affects over 90% of patients and is another means of distinguishing ME from conditions  such as depression, stress, and busy lifestyles. ME and alcoholism don’t go together so if a person claims to have ME and spends every night in the pub downing several pints of beer, there is a distinct possibility that he or she has been misdiagnosed.

3.  Signs of impaired circulation.  Usually, a friend or relative can detect that someone has over-exerted themselves before the patient does, simply because of what one expert called, a ‘ghostly pallor’. Patients may also feel cold when it’s hot and vice versa,  and feel dizzy when standing up (postural hypotension).  It is possible to observe the changes in the circulation of blood in the brain on SPECT and PET scans, especially after exertion. 

To support the diagnosis of ME, it’s useful to know that the illness fluctuates. In short, patients are not ‘tired-all-the-time’. There are people who report constant fatigue, but there are usually other reasons for this, including anaemia. Aside from that, tiredness doesn’t really describe how patients with ME feel.  Some refer to post-exertional malaise (PEM), to focus on the worsening of the unpleasant flu-like symptoms that many experience after relatively minimal activity.  However, there is more to ME than that.

The additional symptoms associated with ME, e.g. blurred vision, bladder disturbances, loss of balance, nausea, sensitivity to foods and chemicals etc are not unique to the illness and therefore don’t help with diagnosis. Indeed, if one chooses to diagnose a condition by ticking off  a list of symptoms as opposed to looking at the type, pattern and severity, the more likely it is that one will include individuals with a condition such as depression. In short, CFS is a catch-all diagnosis with the emphasis on fatigue and pain. ME focuses more on muscle weakness and neurological abnormalities. If one prescribes a treatment for the former, it may not be appropriate or effective for the latter.

Possible causes

Some clues as to the cause(s) of ME come from the epidemics in the mid-fifties and eighties. The onset, transmission, incubation times and specimens from patients suggest that one culprit is an enterovirus. However, I am particularly impressed by a small report on four individuals who were not involved in an outbreak. All the patients were men, the condition did not arise in a closed community and there was no health scare at the time (the author was clearly aware of the mass hysteria explanation). Enterovirus was isolated from the cerebrospinal fluid from two of the men, and from the blood samples obtained from the other two (Innes, Lancet 1970, p.969-970.)

When colleagues suggest that ME no longer exists - and many do -  this paper is the one I cite as two of the patients had the typical features of the disease still seen today. For example, case 1 had issues with alcohol  as well as the better known symptoms relating to post-exertional worsening, balance problems and tiring easily, even three years into their illness. The second case was a doctor with weakness from the waist down, (a symptom I can personally relate to), an intolerance to alcohol (idem ditto) and relapses for over two years. 

The third patient also reported problems with alcohol, weak limbs, dizziness and other neurological symptoms, plus a relapsing-remitting course lasting two years. The fourth patient developed illegible handwriting, but this does not impress me as he was a doctor.  To be fair, the account is too short to draw firm conclusions. However, more comprehensive studies published in recent years have continued to find evidence of enteroviral infection, many years after onset. These results have been published in peer-reviewed, scientific journals so they are not opinions. But enteroviruses may not be the only cause of ME. Other viruses have also been implicated.  


I am a psychologist so not prejudiced against the notion that stress may cause or exacerbate any illness. But having read almost every paper on the subject, and talked to many other experts, I am aware, for example, of studies on monkeys, some of whom became ill having been inoculated with a specimen taken from patients.  Thus whatever causes ME, it can be transferred to animals. There are also papers on an enteroviral disease resembling ME which vets have observed in horses and cows. And I recall an account of  a family with ME where the pet also succumbed, as well as  the brain biopsies from sick cats.  Everything points to an infectious cause that can still be detected in blood and tissue (tonsils, stomach biopsies etc) many years after onset.

Those who continue to claim that ME is a result of anxiety or modern life still have to explain the loss of muscle strength following  minimal exertion 24 hours after finishing the exercise tests, not to mention the abnormalities on brain scans, and even memory tests. And there’s the issue of the epidemics which were documented in the 1930s, long before the internet age, mobile phones and the credit crunch. Sadly, the lack of interest in ME means that the NHS does not re-test, let alone take blood on days when a person feels worse. 


Click here for more articles


Back to top