IOM Recommends New Name, Criteria for Chronic Fatigue Syndrome

Chronic fatigue syndrome (CFS) is an enigmatic condition; this illness can debilitate someone to the point where a simple household chore can be grueling, and even trying to concentrate mentally can be exhausting. At the same time, the condition remains routinely misdiagnosed or dismissed in the medical community.

The confusion over CFS is perhaps well evidenced by the wide variance in estimated prevalence, as recent data suggest it could affect anywhere from 800,000 to 2.5 million Americans. It is also seen in the nomenclature, as in addition to the vague term of CFS, this disease has been called myalgic encephalomyelitis, postviral fatigue syndrome, and others.

In an effort to rein in the various beliefs, diagnostic and otherwise, the Institute of Medicine (IOM) recently published a new report, at the behest of several federal public-health agencies, titled “Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness.”

Based on a comprehensive review of literature and input from patient, advocacy, and research communities, the report proposed a new name—systemic exertion intolerance disease (SEID)—and a new set of standardized diagnostic criteria. The IOM expert committee that composed the report believed these changes more accurately capture the central characteristics of this illness (see box).

“We hope that this report will finally give credence to a real disease with a physiologic basis and that all medical professionals treat it with the respect it deserves,” said Theodore Ganiats, M.D., a professor of family medicine and community health at the Miller School of Medicine at the University of Miami and one of the IOM committee members.

“I do want to stress that while the report emphasized that SEID is a ‘real’ disease, that does not imply that psychiatric illnesses are not real,” Ganiats continued. “The emphasis was meant to clarify that this disease is not just made up in a patient’s mind.”

Pointing out that cognitive impairment remains a critical element for a diagnosis of SEID, Ganiats noted that the psychiatric aspects of SEID should continue to be appreciated. In addition, as a serious chronic illness, SEID brings a greater risk of such accompanying mental health issues as depression or anxiety.

Michael Sharpe, M.D., a professor of psychiatry at the University of Oxford, believes this new designation might be a mixed blessing for patients.

“It appears that this change was driven more by patient preference than new science,” he told Psychiatric News. “The underlying causes of this illness are still shrouded in ambiguity.”

Relabeling CFS may indeed reduce stigma, but Sharpe worries that many people will still be misdiagnosed, while those given an SEID diagnosis may shy away from behavioral therapies that have demonstrated success.

“It doesn’t work for everyone, but rehabilitation through programs like cognitive-behavioral therapy is a proven approach,” Sharpe said. “Now with a new focus on the physical aspects of this condition, patients may lean toward getting more lab tests done to identify a disease process and possibly a pharmacological intervention.”

On this topic, Sharpe also noted that the IOM report did not provide any recommendations for treatments, as it was beyond the scope of the report, though a major purpose in developing a new disease classification is to inform appropriate treatment options.

Akin to Ganiats’ view, though, Sharpe does not discount the biological elements of SEID. “Often medicine doesn’t seem to be able to hold the idea that an illness can affect both the mind and body,” he said. “But in the case of chronic fatigue, and many other complex diseases, a clinician should not be put off in providing an assessment that takes both sides into account.” ■