Buoyed by a spate of recent scientific findings tying the disorder to possible genetic and physiological causes, Center for Disease Control officials said they want chronic fatigue syndrome to join the ranks of "real" diseases.
"The science has progressed," says Julie Gerberding, M.D., director of the CDC, which today began a campaign to raise awareness of the disease among the general public and doctors.
"We are committed to improving awareness that this is a real disease," Gerberding says.
In this effort, the CDC also released brief guidelines pushing physicians to consider chronic fatigue syndrome in symptomatic patients when no other physical or psychiatric explanations can be found.
The guidelines urge the use of moderate exercise, diet modification, and medical treatment for relief of individual symptoms like headache, sore throat, and sleep problems.
Studies estimate as many as 1 million Americans suffer from the disease. Fewer than 20 percent of those with the disease have been diagnosed, according to the CDC.
Chronic fatigue syndrome is defined as severe fatigue — not relieved with rest — that lasts six months or longer, and reduces the patient's ability to do usual daily activities.
Other symptoms include pain in the muscles and joints, problems with memory and concentration, headaches, unrefreshing sleep, sore throat, and tender lymph nodes.
The disorder has been cited as a major cause of absenteeism and lost work productivity, with the cost running in the billions of dollars.
Hard To Pin Down
Still, there is still no lab test, scan, or examination that can reveal chronic fatigue syndrome. It is diagnosed by a patient's history of illness, and after eliminating other conditions.
Also, there is no drug to cure it. Treatment focuses on bringing some relief from symptoms and the return of normal function.
"There's no diagnostic test, no blood test," says Nancy Klimas, M.D., a chronic fatigue researcher at the University of Miami, in explaining the medical community's long frustration with the disease. "These are hard patients, and medical management these days has to be done in six minutes, nine minutes — and that's not going to happen with these patients. These patients slow your day down."
"Historically it's been the lack of credibility of this illness that's been the major stumbling block," she adds.
Fight for Legitimacy
American medical history is rife with examples of diseases not deemed "real" until their physical cause was found.
Depression, long ignored and stigmatized, quickly found legitimacy when researchers realized imbalanced neurotransmitters were more to blame than bad parenting or a lack of personal fortitude.
Now, it appears chronic fatigue syndrome is poised for such a graduation.
Recent scientific findings have linked the problem to abnormalities in the body's autonomic nervous system, which controls blood pressure, heart rate, and other functions.
Meanwhile, genomic studies are beginning to suggest that sufferers carry genes leading their bodies to overreact to stress. In such people, significant stressors like trauma or a major infection could trigger an overresponse that takes the form of chronic fatigue.
"I'm not talking about minor events like public speaking," says William Reeves, M.D., director of the CDC's chronic viral diseases branch.
A study published in the BMJ in September found 12 percent of patients who had serious infections wound up with chronic fatigue symptoms six months later.
Other studies have suggested the illness stems from some kind of hyper-reactive immune system — easily switched into action but hard to turn off.
While the evidence is not definitive, it gos against long-held notions that chronic fatigue syndrome is a figment of patients' imaginations, says Anthony Komaroff, M.D., a professor of medicine at Harvard Medical School.
"In my view, that debate should be over," he says.
Still, theories about a cause remain theories.
Reeves acknowledges that chronic fatigue syndrome is highly variable and unlikely to come with a simple explanation. "There may be more than one."
The CDC wants physicians to understand how to diagnose chronic fatigue syndrome, Gerberding says, "but more importantly be able to validate and understand the incredible suffering."
SOURCES: Julie Gerberding, M.D., director, CDC. Nancy Klimas, M.D., University of Miami, Miami VA Medical Center. William Reeves, M.D., director, chronic viral diseases branch, CDC. Hickie, I. BMJ, Sept.16, 2006; 333:575. Anthony Komaroff, M.D., professor of medicine, Harvard Medical School.
By Todd Zwillich
Reviewed by Louise Chang, M.D