We are talking about a complex and debilitating illness characterised by intense physical and mental fatigue, which does not abate significantly after rest and worsens with physical or mental exercise.
José A. de la Osa
It is known as chronic fatigue syndrome (CFS), and we are hearing from the neurologist Norge Santiesteban Velázquez, a professor and specialist with the Institute of Neurology and Neuroscience’s Group for Neuromuscular Illnesses in Havana.
The onset of this illness, he tells us, forces sufferers to substantially reduce their activity levels, and this reduction is reflected in all areas of daily life. Over time it has been given many imprecise names, including post-viral fatigue syndrome, myalgic encephalomyelitis, abortive poliomyelitis and, going back as far as the nineteenth century, neurasthenia.
Indeed, according to Doctor Santiesteban, this is not a modern disease. In the mid-nineteenth century the American Internist Austin Flint (1812-1886), described it as ‘nervous exhaustion’.
Are the causes of the illness known, or, if not, what hypotheses are being put forward in the scientific world?
The exact cause remains unknown. Some theories suggest that it could be due to infection by the Epstein-Barr virus (EBV) or the human herpes virus type 6 (HHV-6). Among many other hypotheses, the existence of inflammation in the nervous system caused by a defective response by the immune system has also been cited.
Scientists have put forward factors such as age (it tends to be most common in 30 to 50 year olds), previous illness (depression, anxiety, disturbed sleep patterns and fibromyalgia), stress, some environmental agent and genetic predisposition.
Based on world statistics and your own clinical experience, could you describe it as common?
The disease affects around 0.5% of the world population, and the proportion in terms of gender is nine women to every man.
They are similar to those of flu and other common viral illnesses and span muscle pains, headaches and extreme fatigue. However, the symptoms of CFS last six months or more on average, with the predominance of extreme tiredness (fatigue). This tends to be intense and does not get better with rest in bed. Typical CFS also includes discomfort of the pharynx, painful glands, muscle and joint pains and headaches which are different to those the patient may have already suffered. Sleep is often not restorative.
When you experience extreme and persistent fatigue, without necessarily feeling the other symptoms of this disorder. The patient can be examined by their GP, specialists in internal medicine, physiatrists or neurologists.
Is the diagnosis clinical, or does it require complimentary examinations?
It is entirely clinical. There are no specific tests to confirm it.
From a medical perspective, is the diagnosis difficult? Can it be confused with other disorders?
CFS is diagnosed after the physician rules out other possible causes of fatigue such as a dependence on drugs, autoimmune disorders, muscular or neurological diseases and also psychiatric and psychological illnesses, particularly depression or tumours.
What consequences can this lead to in the short and long term?
Possible complications are social isolation as a result of the fatigue, lifestyle limitations (some people become so fatigued that they are essentially disabled throughout the course of the illness), and depression.
What treatments are suggested for these patients?
Once the diagnosis has been carried out, the doctor must provide them with the necessary information about the disease and its possible evolution, in order to avoid the deterioration of healthy lifestyle habits. The most widely-used drugs are antidepressants.
In general, what is the prognosis?
A large proportion of these patients get better with time, and recover completely or partially. Unfortunately, in other cases, the disease seems invariable.
Anything else to add…?
It is vital for these patients to know the importance for their health of not self-medicating, and of systematically carrying out the physical exercises that are indicated to them. These must be supervised by the physiatrist. And I should specify that fatigue is not a synonym of CFS.
(Translated by Alex Thomas)