Chronic Fatigue Syndrome (CFS) sometimes referred to as Myalgic Encephalomyelitis (ME) or Chronic Fatigue and Immune Dysfunction Syndrome, is characterized by persistent or relapsing unexplained fatigue often resulting in severe impairment in daily functioning.
A standard definition2 includes fatigue which:-
- Lasts for at least 6 months
- Is of new or definite onset
- Is not the result of an organic disease or of continuing exertion
- Is not attenuated by rest
- Results in a substantial reduction in previous occupational, educational, social and personal activities.
Four or more of the following symptoms concurrently present for longer than 6 months:
- Impaired memory or concentration
- Sore throat
- Tender cervical or axiliary lymph nodes
- Muscle pain
- Pain in several joints
- New headaches
- Unrefreshing sleep
- Malaise after exertion
Predisposing and precipitating factors:-
Personality and life style or some other factor may influence vulnerability to CFS which is why the illness does not affect everyone exposed to the conditions described below. Three quarters of patients report an infection, such as a cold, flu-like illness or Infectious Mononucleosis (Glandular Fever) before symptoms began. A recent study reported on a significant association between the presence of the XMRV Retrovirus and CFS3. It was not clear whether this finding established a causal link to the development of CFS or it is a passenger virus in an immmunocompromised CFS patient. It was worth noting that nearly 4% of a healthy control population (with no symptoms of CFS) also had evidence of the virus. Subsequent research was unable to confirm these results. Serious life events such as bereavement, or a job or other stressful situation, or even physical trauma may also precede the illness. It is probable that a combination of factors contribute to an alteration in immunity including the ‘permanent distress response’ mentioned below.
Perpetuating factors:-
What seems to underlie many of the symptoms associated with this CFS and other conditions is a dysfunction of the sympathetic nervous system. Dysfunction in this context is a disordered regulation or a disturbance of the fine processes of control which operate normally. This can lead to a state of permanent distress response or sustained arousal. Once CFS has developed, psychological or some other process seems to be involved. A strong belief in a physical cause of the illness, a strong focus on bodily sensations and a poor sense of control over complaints contribute to an increase in fatigue severity and functional impairment.
Health workers including Medical Practitioners can contribute to the persistence of CFS by encouraging unnecessary medical diagnostic procedures, by suggesting psychological causes, or by not acknowledging CFS as a diagnosis, thus causing communication problems. As a physician and a practitioner with considerable experience of working with people with CFS, I am convinced that CFS is not psychosomatic; it is a neurological illness with many of the symptoms described above.
The model of CFS as described, plus the common history of precipitating and perpetuating factors, supports my belief that a retraining programme can be particularly helpful in either effecting recovery or a major shift in symptoms. There needs to be an acceptance by potential trainees that the neurological pathways associated with the physical symptoms can be unlearned and often surprisingly rapidly.
Other management strategies are described in the NICE guidelines published in August 2007. (www.nice.org.uk)
1Prins JB, van der Meer JWM, Bleijenberg G. Chronic Fatigue Syndrome. Lancet 2006; 367: 346-355
2Fakuda K, Straus SE, Hickie I, et al, The Chronic Fatigue Syndrome: a comprehensive approach to its definition and study. Ann Intern Med 1994: 121: 953-959.
3Lombardi VC et al. Detection of an Infectious Retrovirus, XMRV, in blood cells of patients with Chronic Fatigue Syndrome. Science 2009; 326:585-588
