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Shaky Foundation - Part 5

Repair Job: Placing CFIDS Research on a Solid Foundation

By Craig Maupin at

There is now widespread agreement that in order for chronic fatigue syndrome (CFS) research to find itself on a firm foundation, the case definition will need to be revised. As I stated earlier, I am skeptical that a revision is likely to be effective until some of the faulty science, diverse political needs, and unsound supportive ideologies are adequately addressed. Within several weeks prior to this release, two CFSCRC centers published studies derived from many of the problematic ideas that were challenged in this series. This is evidence that the problems within chronic fatigue syndrome (CFS) research will not be resolved any time soon. They are ongoing and entrenched.

The political shell game that led to the formation of a broad case definition in 1994 will have to be replaced by a new admission that patient samples of differing researchers are incongruent. There will have to be an admission that the case definition for CFS has often favored a variety of unmet, yet deserving political needs over solid scientific methods, and the "integrative" approach has led to conflicting results and confusion. In other words, feelings, assumptions, needs, and politics are often the driving force behind the low standards seen in CFS research.

Once an illness is broadened, the broadened case definition can redefine the illness itself, making a firm foundation very difficult to achieve. Many researchers are dependent on the broad chronic fatigue syndorme (CFS) definition for both funding and prominence. Working back into a solid case definition from here will be a long and difficult task. In other words, a lot of damage has been done.

Despite numerous obstacles to reform, what would a solid case definition for CFS look like? A reliable case definition for CFS will affirm clinical differences instead of attempting to blur them in one massive "fatigue syndrome". CFS, Fibromyalgia, multiple chemical sensitivity disorder, and post-traumatic stress disorders may be different illnesses, or they may be related. Either way, a reliable case definition will see the distinctions between these illnesses as valuable scientific information, rather than as hindrances to relieving a broad set of funding needs.

A reliable case definition for chronic fatigue syndrome (CFS) can also be remarkably simple. The longer and more technical the CFS case definition becomes the more suspicious one should be of its effectiveness. During the crafting of the revised 1994 case definition, it would appear that each representative tossed in symptoms they perceived as important to buttress their own research model. In the end, there was no distinctness or simplicity remaining, and a lot of confusion.

There are some logical and straightforward ways the case definition for CFS could be repaired. Of primary importance is the need to emphasize the distinct features of the illness and to classify into groups those symptoms that are variable among individual patients.

Symptoms of CFS

Emphasize and clearly define the hallmark symptom of CFS - The hallmark symptom of CFIDS is a chronic, disabling, and flu-like fatigue that is exacerbated by activity/exertion. The distinct, postexertional aspect of this fatigue should be adequately described. It should be treated in the case definition as the major, required symptom for CFIDS, instead of as non-essential.

Group the Variable Symptoms of CFS by 2 Classifications - Due to the fact that these symptoms vary from patient to patient, they should be classified, rather than dumped into a long, unrelated list. Flu-like, neurological symptoms would be effective headings. It is characteristic of CFS that these symptoms worsen after exertion. No matter how the symptoms vary from patient to patient, this key feature of CFS and should be stated in the section of the case definition preceding the listing of these variable symptoms.

Flu-Like Symptoms – Swollen lymph nodes, fevers, sore throat, flu-like malaise.

Neurological Symptoms – Neurological symptoms such as: sleep dysfunction, cognitive dysfunction, memory loss, headaches, and possibly syncope should fall under this heading. The neurological symptoms of CFS are the symptoms most likely to be shared among the various subgroups of the illness, but they are also the most variable. The authors of the 1994 case definition decided to give each neurological symptom an equal weighting with the hallmark symptom of CFS. This was a trendy but disastrous tool used to encourage researchers to fund different illnesses under CFS research - often taking samples that didn’t have the hallmark symptom of CFIDS. By grouping neurological symptoms under one heading of Neurological Dysfunction, the case definition will achieve more reliable results.

Other Unique Symptoms of CFS

1. Orthostatic Intolerance and circulatory impairment. Recent studies have suggested that this symptom can aid in diagnosis of CFS.

Subgroups and Addressing Unmet Funding Needs

The ineffective case definition for chronic fatigue syndrome (CFS) has often been supported by a desire to use the CFS case definition to meet various unmet funding needs. These suggested subgroups might temporarily address some of these needs, instead of placing them on the funding backburner of "fatigue syndrome" year after year. Subgrouping can also be effective in uncovering important differences and distinctions pertaining to each group.

Fibromyalgia Syndrome – Formal recognition of Fibromyalgia Syndrome, as well as consideration to updating the Fibromyalgia definition, should be tackled before repairing the chronic fatigue syndrome (CFS) case definition. Until this is done, there will be a continued political desire to use a broadened and blurred CFS case definition to attend to the shortcomings of the American Rheumatology’s definition for Fibromyalgia. Symptoms such as fatigue, sleep disorders, and neurological dysfunction need to be added to the definition of Fibromyalgia to affirm the disabling status of Fibromyalgia. Until this happens, the CFS case definition will continue to be used to address the lack of attention and needed reform of the Fibromyalgia Definition.

Also, despite current enthusiasm and rationalizations for integrating Fibromyalgia (FM) research into CFS funding streams, Fibromyalgia Syndrome should have its own well-developed research funding structure. Fibromyalgia is too expansive and widespread of a disease to be integrated into CFS research without reaping unintended consequences, for both those with CFS or Fibromyalgia. Fibromyalgia needs to be recognized as a disabling, unique disease. Formal recognition of Fibromyalgia Syndrome by adding the complete symptoms of Fibromyalgia to the FM definition, as well as encouraging a distinct funding structure for Fibromyalgia, is the only way to begin achieving these goals.

There are several ways that a reliable case definition may deal with Fibromyalgia. The first way is to add the Fibromyalgia symptoms to the CFS definition yet emphasize the hallmark symptoms of CFS. The second way is to strip the CFS definition of FM symptoms and then to recommend researchers/clinicians to add a “co-morbid” diagnosis of FM for those patients that meet both distinct criteria. This would mean that a smaller group of CFS and FM patients would carry two diagnoses. Eventually, as more is learned about both illnesses, I feel this will be accepted as most reliable and scientifically dependable way to go. But for now, the political reality of Fibromyalgia funding pressures at several FM-predominant CFS research centers will be a driving impetus for a definition that continues to move the CFS definition more toward a definition for FMS -- downplaying the distinct features of CFS.

Other Subgroups – Biological Subgroups should be encouraged that look into already published biological differences between CFS patients. Low-molecular-weight Rnase L and orthostatic intolerance are two such subgroups that come to mind.

Severity and Longetivity Subgroups would be helpful as well. Again, simplicity and specific recommendations will be the most effective way of accomplishing this objective.

Psychiatrists researching post-traumatic stress disorder (PTSD) under the current CFS case definition may also want a subgroup. The CDC's William Reeves, in particular, is one researcher with a reputation for funding a personal interest in PTSD under the broad CFS case definition.  However, they need to demonstrate that their research samples weren't simply derived from previously-defined illnesses such as PTSD making their way into their broad, loose research standards. The pertinent question that has not been resolved is whether these illnesses already have a funding structure in place, and if so, would it not be sounder from a scientific standpoint to fund these illnesses in these structures? Just as in the case of Fibromyalgia, achieving a solid case definition will require that the tendency to fund previously defined illnesses in CFS funding streams will need to be reexamined and rethought. Until this happens, subgroups may be the only political solution that doesn't continue to reap a loss of respect for the CFS research community.

Creating interpretable CFS research by quantifying and identifying the content of samples

A reliable and respected research definition would require published CFS researchers to identify and quantify differing fatiguing illnesses that are present in their patient samples! It does not take complex questionaires and symptom inventories to do solid research on CFS.

This standard should be a requirement of any research definition for CFS! The failure to clearly define samples has made it impossible to interpret much of what is published as CFS research. This has led to a deep loss of respect for both CFS research and its researchers. Most CFS researchers publish studies on CFS that do not reveal the quantities of Fibromyalgia, MCS, PTSD, depression, and psychiatric diagnosis comprising their samples. For CFS research to again be interpretable, reliable, and respected, this practice should be frowned upon, not encouraged.

Even so, there has been much resistance to this standard by the CFS research community. But without the enforcement of reliable methods by the definition, CFS research will not be held in esteem. In short, for the CDC's CFS research program and for CFS research to be respected, the inclusion of this standard should not be seen as a trifle but as an absolute necessity.

Summary of Solid Case Definition for CFS

Major or Hallmark Symptom - Chronic, Distinct Flu-like Fatigue: Exacerbated by Exertion and Activity.

Classified Symptoms - Classify in groups the symptoms that vary from patient to patient, yet are still likely to be seen in CFS. Post-exertional exacerbation of these variable symptoms is a common feature of CFS. This should also be emphasized.

Neurological Symptoms – Cognitive Impairment, Syncope, Sleep Disorders, and Short-Term Memory loss, Headaches.

 Flu-Like Symptoms – Sore throat, swollen lymph nodes, fevers.

Orthostatic intolerance, circulatory symptoms - Orthostatic intolerance, low blood volume symptoms, thirst.

Muscle and joint pain - This symptom would be best addressed by suggesting a co-diagnosis of Fibromyalgia for those patients who have both the hallmark symptoms of chronic fatigue syndrome (CFS) and this distinct pain of FM. For research purposes, the inclusion of this symptom in CFS samples may be problematic, until CFS and Fibromyalgia are more clearly differentiated.


Encourage the formal recognition of Fibromyalgia Syndrome - Encourage the proper definition of Fibromyalgia Syndrome by advising the CDC to form a panel to address the needed repair to the Fibromyalgia case definition. Encourage a renewed commitment to independent and increased investigation of Fibromyalgia Syndrome, by advocating Fibromyalgia and FMS be given it's own well-funded poltical structure. Strong consideration should be given to measures that that keep Chronic Fatigue Syndrome (CFS) and Fibromyalgia distinct.

Severity and Longetivity - Encourage the Subgrouping of patients by severity and longetivity.

Encourage Biological Subgroups – Low Molecular Weight Rnase L, Orthostatic Intolerance, ect...

Returning CFS Research to Respect Through Simple, Rather than Complex and Expensive, Clinical Standards – Require researchers quantify and reveal the inclusion of overlapping illnesses in their patient samples. As stated earlier, this is a must.

Conclusion – Well, there it is: a logical case definition for chronic fatigue syndrome (CFS). This definition is amazingly simple compared to the current approach. Trust me when I say, attaining a reliable case definition for CFS is a lot easier on paper than in the real world. Currently, many researchers with many different interests are dependent on the broadness of the CFS case definition for funding and relevance. The current chaos of CFS research is based on the application of an integrative case definition to fund various unmet needs and agendas. The reasons for these problems are not complex, but fixing them is. Funding, egos, and agendas may all stand in the way of progress, reform, and simplification. That, in and of itself, is a sad state of affairs.

But there is hope. A few courageous researchers are beginning to speak out on these problems. These researchers are challenging many of the rationalizations that have led to a flimsy foundation for chronic fatigue syndrome (CFS) research. They are also making clear clinical distinctions. I wish these researchers well. We need more of these bold researchers to speak directly to the current problems in CFS research.

For an emerging illness like chronic fatigue syndrome (CFS), the case definition is the very foundation that will lead to better treatments, research, and results. In 1994, that foundation was shaken, cracked, and overturned, but it can be rebuilt. A shaky ideology can and eventually will give way to sound science. Partisan bickering can be replaced by scientific strength. The CFS research community could be invigorated by a new, reliable case definition. For those who suffer with CFS, an replacing of the Shaky Foundation with a sound ideology based on tried and true scientific methods can’t happen soon enough. It is those of us who suffer from CFS who have born the Shaky Foundation's true cost. It is time for a sound foundation.


Craig Maupin writes for The CFIDS Report ( He can be reached at