Chronic fatigue syndrome (CFS) is a condition of extreme fatigue that persists for more than six months, does not improve with rest, is worsened by physical, cognitive, or emotional exertion, and cannot be easily explained by medical evaluation.
What Is Chronic Fatigue Syndrome?
CFS is a chronic, debilitating condition of extreme fatigue that persists for more than six months and results in a substantially lower level of occupational, educational, or social functioning than experienced prior.
It is characterized by fatigue that worsens with exertion but does not improve with rest and may also include cognitive impairment and autonomic symptoms, such as lightheadedness. It is diagnosed via a thorough medical evaluation for a variety of causes of fatigue. Symptoms often persist for years, although many people experience some improvement in symptoms with time.
Cognitive behavioral therapy and graded exercise programs are evidence-based treatments for CFS. Other symptomatic treatments may also be helpful.
While there is no cure, symptoms can be managed with medication & lifestyle changes.
Chronic Fatigue Syndrome Symptoms
CFS is a chronic disease that can affect anyone and substantially limit life activities. It consists of a variety of symptoms, including:
- Substantial decline in function: People with CFS are unable to engage in occupational, educational, social, or personal activities at the level they were able to prior to developing the syndrome.
- Fatigue: Onset of tiredness is often abrupt. Rest does not significantly alleviate fatigue in CFS.
- : Fatigue worsens substantially after cognitive, emotional, or physical activity.
- Unrefreshing sleep
In addition to the major symptoms above, other symptoms may occur:
- : Many people report swollen lymph nodes, fever, and common cold symptoms at the onset of CFS.
- Cognitive impairment: Difficulties with attention, memory, or problem solving that are worsened by exertion. People with CFS may have difficulty finding words they want to say or feel like they’re in a “brain fog” after exertion.
- Orthostatic intolerance: Lightheadedness, dizziness, or fainting upon standing or sitting up.
- Pain: This includes headaches, joint pains, and muscle aches.
- Immune impairment
Chronic Fatigue Syndrome Causes
Despite extensive research, the underlying cause of CFS remains unknown. Some researchers believe that the condition will eventually be shown to be a complex interplay of genetic, infectious, and environmental factors.
- Immunological factors: A variety of immune system abnormalities (including low levels of certain antibodies and decreased effectiveness of certain immune cells) have been demonstrated in CFS.
- Hormones: Levels of cortisol, a stress hormone, have been found to be consistently lower in people with CFS.
- Infections: CFS can follow infection with Epstein-Barr virus (the virus that causes mononucleosis), and possibly other viruses, but it is not currently thought that all causes of CFS are due to infection or that CFS is due to ongoing viral infection.
- Genetic predisposition: CFS has been found to run in families, suggesting a possible common genetic predisposition.
- : A history of trauma has also been suggested as contributing to CFS. Others have suggested that CFS may be related to manifestations of depression, anxiety, or somatic symptom disorder.
Who is most likely to be affected
Although CFS can affect anyone, it has been found to affect some groups of people more commonly than others.
- Age: CFS is common in young-middle adulthood, with an average age of onset of 33. However, it has been known to affect people throughout the lifespan, including children and the elderly.
- Women: Women are affected twice as often as men.
Treatment Options and Prevention
Reassuringly, many people with CFS experience some improvement in symptoms, although only a minority fully recover. There is no known cure for CFS, but a variety of treatments are available to reduce symptoms. Two treatments (CBT and graded exercise) have been found in clinical research to be particularly effective for CFS.
Cognitive Behavioral Therapy (CBT)
Therapists trained in CBT focus on the relationships between thoughts, feelings, and behaviors. CBT usually occurs in weekly sessions over several months. CBT for CFS can help you understand how your thoughts about activities lead to behaviors that ultimately make you feel more tired. In research studies, CBT has had desirable effects on levels of fatigue, post-exertional malaise, and symptoms of depression and anxiety.
Graded exercise treatment
Carefully planned exercise programs that slowly increase your levels of activity over a few months has been found as effective as CBT for fatigue and functional impairment.
Treatment of comorbid conditions
CFS can be better addressed if certain other underlying conditions are treated.
- Sleep disturbances: Poor sleep can be treated with lifestyle changes such as sleep hygiene and, in some cases, other specific interventions.
- Depression: Depression is common in CFS and can be treated with selective serotonin reuptake inhibitors (SSRIs), such as sertraline (Zoloft) or psychotherapy (talk therapy).
- Pain: Chronic pain can be treated with a variety of over-the-counter or prescription treatments, as recommended by your physician.
*Caution about unproven treatments: Avoid treatments that are not supported by evidence, such as antivirals, immunosuppressants, stimulants, elimination diets, and amalgam extractions, as these may have untoward side effects and minimal benefits.
More research is needed to better understand how to prevent CFS. However, it’s generally advisable to maintain a healthy lifestyle, including:
- Getting quality sleep every night
- Engaging in regular physical activity
- Eating a healthy, well-balanced diet
- Practicing good hygiene to protect yourself from viruses: Wash your hands regularly with soap and water and avoid people who are sick.
When to Seek Further Consultation
If you feel tired all the time
A wide variety of medical conditions can result in feeling tired all the time. If you’re experiencing persistent fatigue, see your primary care physician for an appropriate evaluation. Since fatigue can occur across so many conditions, you may need to work with your physician over multiple appointments to reach the correct diagnosis.
If you are unable to function at your previous level of activity
If you experience an abrupt and significant decline in your ability to perform tasks at home or work, due to cognitive difficulties, fatigue, or physical discomforts, report this concern to your physician. CFS, along with other conditions, can be debilitating and you could benefit from specific treatments or services.
If you are not getting quality sleep
Quality sleep is critical for optimal health and wellbeing. If you do not wake up feeling well-rested, report these concerns to your physician. Your physician may recommend testing for a sleep disorder or provide recommendations to help you get the sleep you need.
Questions Your Doctor May Ask to Diagnose
- Are you having difficulty concentrating or thinking through daily activities?
- How fatigued are you?
- Any fever today or during the last week?
- Do you have trouble sleeping?
- Do you currently smoke?
Self-diagnose with our free if you answer yes on any of these questions.
- Beyond myalgic encephalomyelitis/chronic fatigue syndrome: Redefining an illness: Report guide for clinicians. Institute of Medicine of the National Academies. Published 2015.
- Gluckman S. Chronic fatigue syndrome. Merck Manual Professional Version. Updated July 2018. Y3. ancey JR, Thomas SM. Chronic fatigue syndrome: Diagnosis and treatment. Am Fam Physician. 2012;86(8):741-6.
- Afari N, Buckwald D. Chronic fatigue syndrome: A review. Am J Psychiatry. 2003;160:221-236.