Chronic fatigue syndrome is a complex disease, with multiple symptoms and manifestations , and of which very little is known about its origin and treatment. Hence, it still constitutes a great mystery within the scientific community.

Interestingly, in the 1970s and 1980s it was called the yuppie flu, as it mainly affected young workers who lived in the city and the stress and fast pace of life caused them intense exhaustion.

What is chronic fatigue?

Chronic fatigue syndrome (CFS) is a disorder that causes a person to feel extremely tired or fatigued , which may prevent the person from being able to perform any regular activity or task.

To distinguish chronic fatigue from severe tiredness, the person must have the symptoms for more than six months. In addition, if he or she tries to alleviate them through rest, or physical or mental tasks, it is very likely that they will become even worse.

This disease is constituted as a chronic condition, extremely complex and whose causes are still clear, even interfering in the cardiovascular, endocrine, neurological and immune systems.

Today, it is speculated that this condition affects about 0.5% of the world’s demographics , with women being the most affected in 90% of the cases. In addition, it often appears in conjunction with other diseases such as fibromyalgia or irritable bowel syndrome.

Other names for chronic fatigue (CFS) are myalgic encephalomyelitis/chronic fatigue syndrome (MS/CFS) or systemic stress intolerance disease (STI).

Symptoms

As noted above, to consider this fatigue as extreme fatigue syndrome, they must last for at least six months. The patient affected by chronic fatigue syndrome presents, among many others, the following symptoms :

  • Intense fatigue
  • Hyperthermia or fever
  • Photophobia
  • Hyperacusis
  • Unrefreshing sleep
  • Headache
  • Muscle pain
  • Intolerance to temperature changes
  • Concentration deficits
  • Short-term memory loss
  • Deficit in spatial orientation

Thus, the symptoms of chronic fatigue syndrome can be felt in many aspects of life and affect both the way a person relates to others and the way they interact with elements of the environment in which they live, affecting their achievement of goals, self-image, etc.

Causes

Some time ago, chronic fatigue was considered a psychosomatic disorder , however, it has now been accepted that it cannot be considered a psychiatric disorder, but rather an illness with an organic basis but whose causes are not yet fully known.

Despite the large amount of research on chronic fatigue syndrome worldwide, the origin of this phenomenon is still far from being discovered. Still, some research has reached reliable conclusions suggesting that oxidative stress is an important element of the disease, even though it is not known whether this is a cause or a consequence of CFS.

A 2001 study concluded that an increase in both nitrous oxide (NO) and peroxynitrites would be linked to the origin of several diseases, including chronic fatigue syndrome, post-traumatic stress and multiple chemical sensitivity.

With the passage of time and the advance of science, it was hypothesized that an accelerated pace of life and poor nutrition, among other causes, would cause an abnormal development of the candidiasis fungus, thus triggering chronic fatigue syndrome. However, this theory has been widely criticized and rejected.

On the other hand, some studies conjecture that the toxic substances found in the environment and the chemical elements present in some foods also contribute to weakening the person and causing CFS.

Finally, the influence of sleep quality, recurrent physical and psychological stress or some disorders such as post-traumatic stress disorder has also been noted.

Diagnosis

Chronic fatigue syndrome is unique in that it is difficult to diagnose. For a better assessment of the patient’s condition, the clinician should begin by taking a medical history and conducting a physical examination, with the aim of ruling out any hidden diseases behind these symptoms.

Considering that between 39% and 47% of CFS patients also suffer from depression , it is necessary that an assessment of the patient’s mental state is also carried out. Blood and urine tests should also be performed to rule out the influence of certain drugs.

Despite the difficulties involved in diagnosing CFS, there are eight criteria that have been developed over time, and although there is no consensus opinion on which one is more effective, there are two methods that stand out from the rest. These are the Fukuda diagnostic criteria (1994) and more recent criteria developed by the U.S. National Academy of Medicine (2015).

Fukuda (1994) Diagnostic Criteria

In order to make a diagnosis of CFS according to these criteria, the patient must present

1. Intense tiredness

Chronic and intense fatigue for at least six months and for no apparent reason Moreover, this fatigue does not diminish with rest.

2. Rule out other conditions that could cause fatigue

Exclude any illness that a potential cause of the feeling of tiredness.

3. Present at least four of the following signs for six or more months:

  • Memory and concentration deficits
  • Sore throat when swallowing
  • Muscle pain
  • Non-inflammatory joint pain
  • Headaches
  • Unrefreshing sleep
  • Fatigue after an effort with a course of more than 24 hours

U.S. National Academy of Medicine Diagnostic Criteria (2015)

These much more current guidelines were the first to highlight the possible organic features of the disease.

According to this organization, to make a valid diagnosis of CFS, the patient must have the following symptoms:

  • Significant reduction of energy for the performance of any activity, for at least six months and without apparent cause.
  • Feelings of discomfort after exercise.
  • Non-repairable rest
  • Presenting one of these two symptoms: cognitive impairment or orthostatic intolerance

Other aspects to be taken into account in the diagnosis are the frequency and the degree to which these occur, which should be given, at least in half of the occasions, in a main or severe way.

Treatment

Since it is a chronic disease, there is no cure for it. However, drug therapy to manage symptoms such as muscle pain, sleep disturbance, anxiety or depression , has proven to be effective, with symptoms thriving over time.

In other words, the health intervention is of a palliative type, to cushion the impact that the disease has on the quality of life and to prevent it from generating additional problems that do not necessarily exist with an effective management of the symptoms and the interaction with the environment.

Likewise, cognitive-behavioral intervention to work on emotional aspects, and food re-education, can also be successful as a complement to pharmacological treatment.

Bibliographic references:

  • Bested, A. C.; Marshall, L. M. (2015). Review of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: an evidence-based approach to diagnosis and management by clinicians. Rev Environ Health, 30(4): 223-49.
  • Haney, E., Smith, M.E., McDonagh, M., Pappas, M., Daeges, M., Wasson, N., Nelson, H.D. (2015). Diagnostic Methods for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Systematic Review for a National Institutes of Health Pathways to Prevention Workshop. Ann Intern Med, 162 (12): 834-40.
  • Reeves, W.C., Lloyd, A., Vernon, S.D., Klimas, N., Jason, L.A., Bleijenberg, G., Evengard, B., White, P.D., Nisenbaum, R., Unger, E.R. et. al. Identification of ambiguities in the 1994 chronic fatigue syndrome research case definition and recommendations for resolution. BMC Health Serv Res. 3 (1): 25.