Chronic fatigue syndrome has always been a controversial subject, and some physicians still remain doubtful that CFS even exists as its own illness. Ailing patients certainly have a condition that incapacitates them, but chronic fatigue syndrome remains such an ambiguous disease that it is difficult to diagnose.
In fact, researchers have struggled for decades to define CFS and properly outline the chronic fatigue symptoms that would form the basis of a diagnosis. In 1994, the CDC adopted criteria for diagnosing chronic fatigue syndrome, providing credibility to the disease. But even with that official recognition, debate continues over its legitimacy.
Doctors diagnose chronic fatigue using the CDC guidelines, which say patients likely have CFS if:
They have had severe chronic fatigue for six months or longer. The fatigue can’t be explained by any other medical conditions. They also have four or more of the following symptoms: impairment of memory or cognition, muscle or joint pain, unusual headaches, poor sleep, post-exertional malaise, and sore throat or tender lymph nodes.
Critics argue there are problems with this definition and with the concept of chronic fatigue syndrome. These problems include:
No cause has been found for chronic fatigue syndrome. Researchers have not been able to determine any specific cause for CFS. Suspected risk factors vary widely — the patient’s personality is a potential contributor to CFS, as are possible problems with the immune system, nervous system, or endocrine system. Researchers also suspect some sort of infectious agent might be involved. Chronic fatigue symptoms overlap with those of other diseases. A number of conditions, illnesses, and diseases cause chronic fatigue and other symptoms attributed to CFS. These conditions include major depression, fibromyalgia, neurasthenia, chemical sensitivities and allergies, chronic mononucleosis, hypothyroidism, sleep apnea and narcolepsy, bipolar disorder, schizophrenia, eating disorders, cancer, autoimmune diseases, hormonal disorders, infections, obesity, alcohol or substance abuse, and reactions to prescribed medications. CFS is diagnosed by exclusion. Chronic fatigue doctors have not been able to identify specific symptoms only caused by CFS and have no laboratory test for use in diagnosis. The disease is only diagnosed after all other explanations have been exhausted. Doctors must consider all other illnesses listed above before they can diagnose chronic fatigue syndrome.