Definition

Chronic fatigue syndrome (CFS) is a condition characterized by prolonged fatigue (lasting at least 6 months) that cannot be explained by other medical conditions. The fatigue worsens with physical activity or strong emotional experiences but does not improve with rest. Other typical characteristics of CFS include:

• Not feeling fully rested after sleep
• Difficulty remembering, focusing, and concentrating
• Headaches that worsen with changes in position, such as moving from lying down or sitting to standing

This condition is also known as myalgic encephalomyelitis (ME) or systemic exertion intolerance disease (SEID).

The exact cause of CFS is still unknown, although there are several theories that link it to viral infections or psychological stress. Some experts believe that chronic fatigue results from a combination of these factors.

There is no specific test to diagnose CFS. A physical exam and lab tests are necessary to rule out other medical conditions with similar symptoms. Treatment focuses on managing the symptoms of CFS.

Causes

The exact cause of CFS is still unclear. Some people may be predisposed to developing the syndrome, and its onset is often influenced by environmental and emotional factors. Potential triggers for CFS symptoms include:

• Viral infections. Some people develop CFS symptoms after a viral infection, leading experts to suspect certain viruses as a cause. Suspected viruses include Epstein-Barr virus and human herpesvirus 6. However, there is no conclusive evidence linking these viruses directly to CFS.
• Immune system problems. Some cases of CFS involve immune system dysfunction, although the severity of the dysfunction required to cause CFS is not yet known.
• Hormonal imbalances. Some people with CFS experience abnormal hormone levels. The adrenal glands and hypothalamus may not produce certain hormones at normal levels. The significance of these hormonal changes in relation to CFS is still unclear.
• Physical or emotional trauma. Some individuals report major events such as accidents, surgeries, or severe emotional stress prior to the onset of CFS.

Risk Factor

Factors that may increase the risk of developing CFS include:

• Age. CFS can occur at any age, but it is more common in younger to middle-aged adults.
• Gender. Women are more frequently diagnosed with CFS than men, likely because women are more inclined to report symptoms to doctors and receive a clinical diagnosis.

Symptoms

CFS symptoms vary greatly from person to person, and the severity can fluctuate throughout the day. Common signs and symptoms include:

• Persistent fatigue
• Difficulty remembering or concentrating
• Sore throat
• Headaches
• Enlarged lymph nodes in the neck and armpits
• Unexplained joint pain
• Dizziness or lightheadedness triggered by changes in position
• Non-restorative sleep
• Feeling fatigued after minimal physical activity

Diagnosis

There is no specific physical exam or test to diagnose CFS. Its symptoms can resemble other conditions, such as:

• Sleep disorders. People with sleep disorders such as insomnia, restless legs syndrome, and insomnia may experience chronic fatigue. Before diagnosing chronic fatigue syndrome, the doctor needs to confirm that the complaint of sleep disturbances is not due to a sleep disorder. This must be done because it will influence the treatment provided. A sleep study, which involves measuring the quality and duration of your sleep, can assist the doctor in determining this.
• Other medical conditions. Fatigue is a common symptom of conditions like anemia, diabetes, and hypothyroidism. Before confirming a diagnosis of chronic fatigue syndrome, doctors may perform blood laboratory tests to rule out the conditions listed above.
• Mental health disorders. Mental health conditions such as depression and anxiety can cause prolonged fatigue. Before diagnosing chronic fatigue syndrome, your doctor will need to rule out any other mental health diagnoses.

CFS can also occur alongside other conditions like sleep disorders, irritable bowel syndrome, fibromyalgia, depression, and anxiety.

Diagnostic Criteria

The criteria used in the U.S. to diagnose CFS are set by the Institute of Medicine. These criteria include:

• Severe fatigue that significantly interferes with daily activities
• A clear onset of symptoms
• Symptoms that do not improve with rest
• Worsening of symptoms with physical activity or emotional stress

In addition to the above, individuals must also have one of the following symptoms:

• Cognitive difficulties, such as memory problems or difficulty concentrating
• Dizziness or headaches that worsen with positional changes

These symptoms must persist for at least 6 months, and their intensity should be moderate to severe for a minimum of 3 months.

Management

There is no cure for CFS. Treatment focuses on relieving symptoms.

Medications

• Antidepressants. Many people with chronic medical conditions also experience depression. Treating depression may help reduce fatigue and improve sleep. Low-dose antidepressants can also improve sleep quality and reduce pain.
• Antihypertensives. Medications that regulate blood pressure and heart rhythm can help manage headaches and dizziness caused by changes in position.
• Pain relief. If over-the-counter pain relievers like ibuprofen are ineffective, doctors may prescribe medications used to treat fibromyalgia.

Therapies

• Counseling. Talking to a therapist can help develop coping strategies for living with a chronic illness like CFS.
• Sleep management. Improving sleep quality is crucial. Doctors may advise avoiding caffeine and implementing good sleep hygiene.
• Exercise. While intense exercise can worsen symptoms, maintaining low-intensity physical activity can improve overall function over time.

Post-Exertional Malaise

Individuals with CFS may experience intense fatigue following physical or mental exertion. It's important to balance work and rest to manage symptoms. Keeping a journal may help identify activities that trigger fatigue.

Complications

CFS can lead to:

• Reduced ability to perform daily activities
• Frequent absences from school or work, reducing productivity
• Social withdrawal
• Depression

Prevention

There is no known way to prevent CFS, but early consultation with a doctor can help manage symptoms. Keeping a journal of daily activities can prevent overexertion on good days, helping to avoid fatigue in the days following.

When to See a Doctor?

Chronic fatigue can be caused by various medical conditions such as infections, anemia, or mental health disorders. If prolonged fatigue interferes with daily activities, consult a doctor for a proper diagnosis and treatment plan.