The Institute of Medicine (IOM) recently released their report regarding a new name (i.e., systemic exertion intolerance disease) and case definition for chronic fatigue syndrome (CFS). In brief, the IOM proposed that at least four symptoms needed to be present to be included in this new case definition: substantial reductions or impairments in the ability to engage in pre-illness levels of occupational, educational, social or personal activities; post-exertional malaise; unrefreshing sleep; and at least one of the two following symptoms: cognitive impairment or orthostatic intolerance.
Melvin Ramsay, the distinguished British physician who helped create the first diagnostic criteria for myalgic encephalomyelitis (ME), also specified four domains within the original ME case definition. However, in 1988, the Centers for Disease Control renamed this illness CFS, and expanded the case definition’s domains to eight. In addition to patient discontent over the name change to CFS, the muddled case definition had a number of problems as it is well known that as unexplained somatic symptoms increase, there is a greater likelihood of identifying individuals who have psychiatric comorbidities.
If there are ambiguities with case definitions, there will be difficulties in replicating findings across different labs, estimating the prevalence of the illness, consistently identifying biomarkers, and determining which treatments help patients. To develop or validate a reliable case definition, we need to provide operationally explicit criteria for a case definition, and develop a consensus within the scientific community on the case definition. The members of the preeminent IOM body are distinguished scientists and clinicians, and many are leaders within the ME and CFS fields.
However, regarding their proposed case definition, there is considerable evidence that cognitive impairment should belong to the group of cardinal and required symptoms. Orthostatic intolerance doesn’t evidence prevalence rates as high as the other proposed core symptoms, nor is there any clear justification of requiring patients to have either cognitive impairment or orthostatic intolerance. (I do not know of any factor analytic study that has separated the symptoms into this particular structure.) There may be different groupings of patients (different features, levels of severity) and this was not adequately addressed. Empirical methods could have been employed to test the proposed classification system. It is unclear why the committee members limited themselves to surveying extant studies rather than testing out their proposed model with an actual data set, particularly as they proposed a specific constellation of symptoms that had not been previously investigated. It was also a mistake to apply identical diagnostic criteria to both children and adults. Finally, there is a clear need to exclude those who have a primary affective psychiatric disorder, as including these patients in the case definition would confound the interpretation of epidemiologic and treatment studies, and complicate efforts to identify biological markers for this illness.
There are steps that could remedy some of the above issues.
First, there are a number of existing data sets that could be used to explore and validate this new diagnostic system. Compare the findings with other case definitions.
Second, there has been considerable discussion among patient groups regarding prominent differences among patients. There is a need for studies to determine whether distinct categories or continuous measures best capture these differences. Employ both large data sets and sophisticated research methods to address such investigations.
Third, due to the secrecy inherent in the IOM committee process, there was a significant breakdown in communicating with other government efforts (such as the ongoing Pathways to Prevention effort), as well as the larger scientific and patient community. The IOM report has a comprehensive section devoted to dissemination activities, indicating that the committee members clearly understood the importance of gaining support from key constituencies and gatekeepers. However, the patient and scientific community could have been actively involved in selecting the case definition and its criteria prior to the dissemination effort. This involvement would represent a departure from the process that has historically existed, and which patient activists have bitterly challenged.
An alternative vision is still possible if those in power are willing to bring all interested parties to the table, including international representatives, historians on the science of illness criteria, and social scientists adept at developing consensus. In a collaborative, open, interactive, and inclusive process, issues may be explored, committees may be charged with making recommendations, and key gatekeepers may work collaboratively and transparently to build a consensus for change. Involve all parties — patients, scientists, clinicians, and government officials — in the decision-making process.
Headline image: © Spotmatik via iStockphoto.
“Dislodging CFS” without ever solving the Tahoe outbreak is the fulfillment of Stephen Straus’s vision to derail science by giving the syndrome a trivializing name.
Well said, Lenny! Thanks so much.
I support what Dr; Jason said on many levels. This should be an international effort, not just a US one. It should also have involved individuals more representative of the entire US. Do people from IOM really have more “on board” than the rest of us? Does Stanford and Harvard have an edge that the rest of us lack? The implications here are tremendous, and this movement ended up with many people who know and understand this illness not having a voice.
Although I agree with about 99.9% of what Dr. Jason says, I don’t understand why those with a primary affective psych disorder (i.e., depression) should not be allowed the ME/CFS/SEID diagnosis. Depression is often co-morbid with ME/CFS/SEID. So why exclude patients who have it from being diagnosed with SEID? I am aware that many people with depression have disabling fatigue, but I haven’t read that depression causes Post-Exertional Malaise (PEM). So if having PEM is a required criteria for being diagnosed with SEID, that should help avoid patients who have depression-related fatigue (that don’t have SEID) from being diagnosed with SEID. Any ideas, anyone? Am I missing something here?
JA: I think the IOM are trying to cover two purposes. Clinical and Research.
I think it is essential that people with a “primary” diagnosis of “clinical” depression be excluded from the diagnostic definition of ME for the purpose of research. While many of the symptoms are similar, they do appear to be distinct illnesses. If we included people with depression that would leave only Post Exertional Malaise as the definitive symptomatic diagnostic.
That would be a BIG mistake as PEM is NOT an absolute distinctive symptom. It is the most common distinguishing symptom.
I also disagree strongly with naming an illness such as this from a symptom (SEID). It is premature to create a new name. Stick with ME for now, until we have enough immunological variables to give it a name or many names.
On a personal level I found that any psychological events came long after the initial very disabling illness, & then only after many months of clinicians not being able to identify or quantify the illness. It was the ongoing crippling symptoms with no end in sight & no cure or apparent reason for the onset of the symptoms that finally started to crack me up. Seemingly with no real support from anybody in the medical world except my then GP, who had known me as a very busy & active person within the community, with a busy family lifestyle, work, hobbies & varied interests, he was th only person at that point who actually said-‘I think this is ME, but you will get better, though I can’t tell you when, I’m sorry I cannot give you a magic cure, but stay positive’. The positive took some doing but nearly 22 years later I still have the ME, though not as severe, & also other health problems developed over the years-but I am positive! I weep when I see that the sceptics are still very much in charge of our care! Let them have a dose & see what they make of it!
[…] March, Professor Leonard A Jason outlined his serious concerns around the report: The IOM’s efforts to dislodge Chronic Fatigue Syndrome […]
[…] IOM also released a new case definition to replace CFS, and our published work now suggests that these new criteria would almost triple the prior CFS […]