Chronic Fatigue Syndrome (CFS)

CFS overview   Symptoms   Nutritional discussion
Causes: Onset   CNS & Hormones   Immune   Viral   Hypotension   Sleep   Other causes

Chronic fatigue syndrome (CFS) is defined as disabling fatigue lasting more than six months that reduces activity by more than half. No single cause for CFS has been identified. Suggested causes include chronic viral infections, food allergy, adrenal gland dysfunction, and many others; but none has been convincingly documented in more than a minority of sufferers. Contrary to the myth that there is nothing you can do to speed up recovery from chronic fatigue other than rest and wait, there are a number of proactive things you can do to help recover.

Symptoms

In addition to fatigue, there may also be muscle pain, joint pain not associated with redness or swelling, short-term memory loss, and an inability to concentrate. Some people with chronic fatigue syndrome also experience difficulty sleeping, swollen lymph nodes, and/or mild fever.

Causes

There are many theories about the cause for chronic fatigue syndrome and while doctors mostly accept it as a real disease, there is a substantial controversy as to whether research should focus on physiological or psychological considerations. None of the causes explain all cases of CFS and there are no consistent means to objectively measure biological factors such as a blood test or brain scan.

Experts feel that chronic fatigue may develop from a variety of factors that add up to the resulting condition or the importance of the sequence of factors, whether they act alone or in combination, and whether a genetic or other abnormality makes patients more at risk. Many cases do begin with great physical or mental stress or over work combined with a viral or other infection.

• Hereditary factors
• Abnormalities in the brain
• An over active immune system
• Viral and other infections
• Mental or emotional stress

Sudden- and Gradual-Onset CFS

Some researchers classify CFS as either sudden-onset or gradual-onset, and feel that each class may have different causes. Less than 1/2 of CFS patients experience gradual-onset CFS. It is theorized that gradual-onset might develop from emotional/mental causes and sudden-onset by viral infection or neurological abnormality, as indicated by results of MRI scans of the brains of some patients that showed small injuries.

Central Nervous System and Hormone Abnormalities

Abnormalities in the central nervous system have been reported. Read more about CNS and hormone abnormalities.

Immune System Abnormalities

Researchers have found a number of abnormalities in the immune system. Read more about immune system abnormalities.

Viral Causes

Chronic fatigue syndrome resembles the symptoms of viral illness that does not improve and so attention has been focused on the idea that it was at least partially caused by a virus in the first place, or that a viral infection damages the immune system which remains active after the virus itself has been defeated, or that such an abnormal immune system reactivates an inactive virus that exists in the body.

Evidence for Viral Cause

• CFS begins suddenly with a flu-like condition 80% of the time.
• CFS reportedly begins in same U.S. household, same workplace, etc, but this is not confirmed.
• CFS in the U.K. was found that to possibly be related to previous infections.
• Some believe that normal intestinal bacteria might be a factor.
• CFS patients often have unusually high antibody levels for fatigue-causing viruses, such as candida, Lyme, herpes, HTVL, Epstein-Barr, coxsackie B, measles, parvovirus or cytomegalovirus.

Evidence Against Viral Cause.

• It does not appear to be contagious or spread in the way a cold might spread.
• It is not spread by sexual contact.
• No single virus or other micro-organism has been connected to CFS.

Neurally Mediated Hypotension

• Some CFS patients also have neurally mediated hypotension (NMH) which results in a sudden and marked drop in blood pressure when standing. It is possible that this condition is brought about by damage to the central nervous system as the result of infection.
• This abnormality of the CNS tells the heart to slow so that blood pressure drops when the person changes posture resulting in inadequate circulation and resulting in light-headedness, etc.
• Interestingly, it is reported that patients with this NHM-connected chronic fatigue syndrome are younger and recover more quickly.
• Postural orthostatic tachycardia syndrome (POTS) , a mild form of hypotension, may also be connected to CFS.

Disturbed Circadian Rhythms

• CFS may result from a disordered circadian rhythm and tied to mental or physical over-exertion and stress which hampers their ability to restore their natural sleep and wakefulness cycle.
• Experts further postulate that such abnormal sleep-wake cycle and the resulting tiredness causes the person to not get sufficient exercise, further exacerbating the condition.
• However it has been reported that patients with chronic fatigue are just as physically fit as those without the condition. This means that CFS isn't caused by a sedentary lifestyle, but that the activity level is low due to the condition itself.

Psychosocial Factors

Mental and emotional factors are decidedly connected to CFS in most patients. They probably are not the primary cause but certainly may contribute to vulnerability. And of course, having CFS is mentally and emotionally stressful.

Other Theories

• Muscle Defect. CFS patients often feel as though their muscles don't work correctly leading some to propose that a physical problem might be involved, but this has not been substantiated by chemical, physical or metabolic research.
• Some propose that hyperventilation, caused by asthma, infections, hyperthyroidism, and anxiety might be a factor. Although the condition has been found in some patients research has not substantiated it.
• The vagus nerves provide communication from the brain, through the chest to the intestines and transmits information about the condition of the organs to the central nervous system. It has been noted that after chronic fatigue patient exercise the activity of this nerve is slightly abnormal. There has been no substantive research connecting the abnormality as a cause.
• Mitochondria are the energy producers of the body. Inherited mitochondria mutations cause muscle pain and fatigue and muscle pain. Such mutations might also result from environmental and infectious attacks on the body. More research is needed.

Conventional Treatment

Medical professionals employ a combination of healthy diet, lifestyle amendments, exercise, reducing stress, and counseling. Prescription medications may also be used and include anti-anxiety drugs, antidepressants, hydrocortisone, and pain relievers.

Chronic Fatigue News

Want to learn more? See our blog news on chronic fatigue.

Research

See research on which the above discussion is based.

See additional research.

CFS overview   Symptoms   Nutritional discussion
Causes: Onset   CNS & Hormones   Immune   Viral   Hypotension   Sleep   Other causes