Chronic Fatigue Syndrome (CFS) is a severe neuroimmunological disorder characterized primarily by prolonged, intense fatigue. This can be accompanied by many other complaints such as sleep disorders, sore throat or muscle pain, difficulty concentrating and an increased susceptibility to infections. The exact causes of CFS have not yet been finally clarified. You can read here how chronic fatigue syndrome develops and what the diagnosis and treatment look like.
ICD codes for CFS: G93
Chronic Fatigue Syndrome (CFS) is what physicians refer to as a serious and multifaceted neuroimmunological disease (neuroimmunological = affecting the nervous and immune systems). The main symptoms are debilitating mental and physical fatigue and fatigue that cannot be explained by a known physical cause or specific mental disorder. In addition, those affected have a wide variety of other complaints.
Typically, CFS symptoms worsen after even minimal physical or mental exertion. Protection or rest do not bring any lasting improvement. The performance and quality of life of the patients are often severely impaired for years. Many of those affected can no longer work and are bedridden. Some require extensive care. The level of suffering associated with this disease is often high because it is sometimes not recognized or is not taken seriously by those around the affected person.
In the past, CFS was often considered a mental illness. But that has been disproved – CFS is now viewed as a multi-system disease that affects the immune system and energy metabolism, among other things.
Controversy about the correct name
There are different definitions and classification criteria for Chronic Fatigue Syndrome. The naming of the clinical picture is also not uniform (internationally) and is sometimes controversial:
For example, Chronic Fatigue Syndrome (CFS) is often referred to as myalgic encephalomyelitis (ME), especially in Great Britain and Scandinavia – here, a comprehensive inflammation of the central nervous system (encephalitis myelitis = brain and spinal cord inflammation) with muscle involvement (myalgic) is regarded as the cause of the disease . Other experts prefer to use the combined term ME/CFS.
In Europe one often speaks of chronic fatigue syndrome, sometimes also of chronic fatigue syndrome. However, these terms are rejected by many experts and those affected as trivializing – the severe persistent weakness or exhaustion (fatigue) of CFS patients has nothing to do with simple exhaustion or tiredness. In addition, those affected suffer from many other complaints, not just from pathological exhaustion.
In addition, CFS should not be confused with the fatigue that often occurs with cancer or other serious, chronic diseases and is known as fatigue syndrome. Although this causes similar symptoms, it has a different cause. There are also similarities with the symptoms of other diseases such as fibromyalgia, which is one of the rheumatic diseases.
It is not possible to say exactly how often chronic fatigue syndrome occurs in Germany or other countries – the information varies considerably, possibly because there are no uniform diagnostic criteria and the disease is often not recognized. According to the Federal Association of Chronic Fatigue Syndrome, an estimated 300,000 people in Germany suffer from chronic fatigue syndrome. This estimated value results from applying corresponding American studies on CFS frequency to Germany. About 17 million people worldwide are believed to have CFS.
Women are affected significantly more often than men. Chronic Fatigue Syndrome can occur at any age. Very often those affected are between 29 and 35 years old when the disease breaks out (mean age at diagnosis).
Symptoms of chronic fatigue syndrome
Chronic Fatigue Syndrome is a complex clinical picture that usually develops suddenly – often after a viral infection. But there are also sufferers in whom CFS has developed insidiously over a long period of time.
Experts use different catalogs of criteria to diagnose “chronic fatigue syndrome”. For example, the Canadian Consensus Criteria (CCC) and the International Consensus Criteria (ICC) are frequently used:
Canadian CFS criteria
According to the Canadian Consensus Criteria (CCC), chronic fatigue syndrome requires all of the following symptoms to be present:
• Fatigue: New onset, unexplained, persistent, or recurrent physical or mental fatigue that significantly decreases the patient’s activity level
• Post-exertional Malaise and/or Fatigue: After exertion, there is unusual fatigue, worsening of malaise, pain, and/or worsening of other symptoms. The patient takes more than 24 hours to recover.
• Sleep disorders: eg non-restorative sleep, disturbed day-night rhythm
• Pain: eg muscle and/or joint pain, new types of headaches.
In addition, at least two neurological or cognitive manifestations must be present, for example confusion, impaired concentration and short-term memory, word-finding disorders, impaired movement coordination (ataxias).
Another requirement for diagnosis, according to the Canadian criteria, is having at least one symptom in at least two of the following categories :
• Autonomous manifestations: e.g. extreme paleness, dizziness, nausea and irritable bowel syndrome, bladder dysfunction, palpitations with or without cardiac arrhythmia
• Neuroendocrine manifestations: eg frequent low body temperature, sweating, intolerance to heat and cold, loss of appetite or increased appetite, noticeable weight change, aggravation of symptoms with stress
• Immunological manifestations: e.g. tender lymph nodes, recurrent sore throat, recurring flu-like symptoms, new onset of hypersensitivity to food, drugs and/or chemicals
Last but not least, the symptoms must have existed for at least six months (three months in children) so that the diagnosis “chronic fatigue syndrome” can be made.
International CFS criteria
According to the International Consensus Criteria (ICC), having symptoms for at least six months is not a prerequisite for a diagnosis of chronic fatigue syndrome. The doctor can certify a person affected by CFS earlier if the following criteria are met:
• Postexertional neuroimmune exhaustion (PENE), ie after physical or mental exertion, there is a disproportionate worsening of the symptoms (physical and mental exhaustion, muscle pain, cardiac arrhythmia, etc.), which can last for hours or days. Neither sleep nor rest will help. PENE is considered a cardinal symptom that must be present in any case of chronic fatigue syndrome.
• At least 1 symptom from the neurological impairment category, e.g. pain, sleep disturbances, memory and concentration disturbances, muscle weakness, disturbances in the coordination of movements, sensitivity to smells, sounds, light or touch
• At least 1 symptom from the category of immunological, gastrointestinal and urogenital impairments, eg chronic respiratory infections, increased susceptibility to infections, food intolerance, irritable bowel syndrome, urinary disorders
• At least 1 symptom from the energy production and ion transport disorder category, e.g. cardiac arrhythmias, tachycardia, low blood pressure, dizziness, inability to adjust the circulation to an upright body position (orthostatic intolerance), sweating, shortness of breath, intolerance to heat/cold and severe temperature fluctuations.
Causes and risk factors of chronic fatigue syndrome
What exactly causes chronic fatigue syndrome has not yet been finally clarified. According to recent investigations, it seems to be an autoimmune disease (dysregulation of the immune system) and a severe disruption of the energy metabolism in the mitochondria (“power plants” of the cells). This is indicated by several studies in recent years. In addition, a variety of factors are discussed that can predispose, trigger, or perpetuate CFS.
Antecedent (predisposing) factors
Chronic fatigue syndrome is usually preceded by an infection. This infection often occurs during a phase characterized by stress or high levels of physical activity.
In addition, some experts suspect that some people have a genetic susceptibility (genetic predisposition) to CFS. This is indicated by twin studies. So far, however, no specific risk genes for chronic fatigue syndrome have been identified.
Most patients cite infection as the cause of chronic fatigue syndrome. There are cases in which CFS has occurred, for example, after an infection with Epstein-Barr viruses (infectious mononucleosis) or enteroviruses (e.g. influenza), after dengue fever, Q fever or Lyme disease.
In addition to such infections, severe injuries, operations, pregnancy or childbirth sometimes also trigger chronic fatigue syndrome. Stressful events such as the death of a loved one or unemployment can also act as triggers for CFS.
Physical overload and mental stress can increase the symptoms of chronic fatigue syndrome. Also, if patients are unable to work due to CFS, receive little social support and/or become depressed, this can worsen the course of the disease. The same applies if those affected are not taken seriously by those around them (family, friends, colleagues, doctors, etc.).
Operations and accidents can also lead to an acute increase in symptoms. Another problem is the increased susceptibility to infections that often accompanies CFS: Many patients suffer from the symptoms of chronic fatigue syndrome for weeks after an infection. Similarly, allergies and food intolerance can adversely affect the condition of CFS sufferers.
Diagnosis of chronic fatigue syndrome
Chronic Fatigue Syndrome is difficult to diagnose and in many cases goes unrecognized. There are no specific laboratory or machine tests that will confirm the diagnosis of CFS. In addition to the precise collection of the medical history with all the symptoms that occur, the primary aim is to rule out other diseases that can cause symptoms similar to chronic fatigue syndrome. These include, for example:
• Thyroid, heart and liver diseases
• Anemia, for example as a result of iron deficiency
• Diabetes (diabetes mellitus)
• Neurological diseases such as multiple sclerosis (MS)
• Rheumatological diseases (such as rheumatoid arthritis)
• Infectious diseases such as chronic hepatitis or Lyme disease
• Tumor diseases
• Severe mental illness (such as depression)
• Alcohol, drug or medication abuse
• Pronounced obesity (severe obesity)
Various tests may be necessary to rule out such factors, such as a physical examination, ultrasound and blood tests. Once this is done, the doctor can use a list of criteria (see “Symptoms” above) to check whether the patient has the necessary characteristics of chronic fatigue syndrome. If so, the diagnosis of CFS can be made.
Treatment of chronic fatigue syndrome
So far, experts have not agreed on how best to treat chronic fatigue syndrome. One thing is certain: CFS therapy should be individually adjusted. It is based on the most distressing symptoms (e.g. sleep disorders, pain) and concomitant diseases and should include both drug and non-drug measures.
Medicines such as painkillers can be used, for example, for joint pain and headaches. If depression accompanies the illness, treatment with antidepressants may also be necessary. If the patient has a (chronic) infection, this should be treated specifically, for example with antibiotics in the case of a bacterial infection. If a lack of certain vitamins or minerals (such as vitamin D, zinc, iron) can be detected, it can make sense to compensate for the deficit with appropriate preparations.
Note: Targeted drugs for CFS are not yet available. Scientists are currently researching, for example, the effectiveness of drugs that regulate the immune system.
In general, a regular daily routine is recommended for CFS. Overexertion is strongly discouraged because it can make symptoms worse. For the same reason, those affected should also avoid emotional stress if possible.
Relaxation methods such as autogenic training or other methods for reducing stress often prove to be helpful . For example, they can help CFS patients with sleep disorders. In addition, changing the diet (sufficient vitamins and minerals, high in protein, sufficient unsaturated fatty acids) and avoiding and eliminating harmful substances also sometimes appear to reduce the symptoms of CFS in some cases.
CFS: disease course and prognosis
It is difficult to predict how chronic fatigue syndrome (CFS) will develop in an individual case.
In most cases, the disease begins suddenly, often as a result of an infection: The persistent exhaustion and poor performance can be so pronounced that those affected hardly ever leave the house. Chronic fatigue syndrome can improve again after months or years – whether spontaneously or as a result of a specific treatment cannot usually be said. However, the regained ability to perform is often not permanent: chronic fatigue syndrome has a high recurrence rate; Especially after infections, physical exertion and periods of stress, the paralyzing and persistent exhaustion can set in again. Some of those affected by CFS are permanently restricted in everyday life (up to the point of disability) as a result of the disease.
In rarer cases, chronic fatigue syndrome does not appear suddenly, but gradually. Over time, the symptoms get worse and worse. If a chronic fatigue syndrome takes this course, the chances of recovery are significantly worse.