Myalgic encephalomyelitis: International Consensus Criteria

Abstract:

The label ‘chronic fatigue syndrome’ (CFS) has persisted for many years because of the lack of knowledge of the aetiological agents and the disease process. In view of more recent research and clinical experience that strongly point to widespread inflammation and multisystemic neuropathology, it is more appropriate and correct to use the term ‘myalgic encephalomyelitis’ (ME) because it indicates an underlying pathophysiology. It is also consistent with the neurological classification of ME in the World Health Organization’s International Classification of Diseases (ICD G93.3).

Consequently, an International Consensus Panel consisting of clinicians, researchers, teaching faculty and an independent patient advocate was formed with the purpose of developing criteria based on current knowledge. Thirteen countries and a wide range of specialties were represented. Collectively, members have approximately 400 years of both clinical and teaching experience, authored hundreds of peer-reviewed publications, diagnosed or treated approximately 50 000 patients with ME, and several members coauthored previous criteria. The expertise and experience of the panel members as well as PubMed and other medical sources were utilized in a progression of suggestions/drafts/reviews/revisions.

The authors, free of any sponsoring organization, achieved 100% consensus through a Delphi-type process. The scope of this paper is limited to criteria of ME and their application. Accordingly, the criteria reflect the complex symptomatology. Operational notes enhance clarity and specificity by providing guidance in the expression and interpretation of symptoms. Clinical and research application guidelines promote optimal recognition of ME by primary physicians and other healthcare providers, improve the consistency of diagnoses in adult and paediatric patients internationally and facilitate clearer identification of patients for research studies.

© 2011 The Association for the Publication of the Journal of Internal Medicine.

Comment in: A controversial consensus–comment on article by Broderick et al. [J Intern Med. 2012]

 

Source: Carruthers BM, van de Sande MI, De Meirleir KL, Klimas NG, Broderick G, Mitchell T, Staines D, Powles AC, Speight N, Vallings R, Bateman L, Baumgarten-Austrheim B, Bell DS, Carlo-Stella N, Chia J, Darragh A, Jo D, Lewis D, Light AR, Marshall-Gradisbik S, Mena I, Mikovits JA, Miwa K, Murovska M, Pall ML, Stevens S. Myalgic encephalomyelitis: International Consensus Criteria. J Intern Med. 2011 Oct;270(4):327-38. doi: 10.1111/j.1365-2796.2011.02428.x. Epub 2011 Aug 22. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3427890/ (Full article)

 

Chronic fatigue syndrome: Is it one discrete syndrome or many? Implications for the “one vs. many” functional somatic syndromes debate

Abstract:

There is a current debate as to whether “functional somatic syndromes” (FSSs) are more similar to or different from each other. While at the same time, there is evidence of heterogeneity within single syndromes. So, it could be that these syndromes are all part of one big process/illness, are discrete in their own right, or that they are heterogeneous collections of different illnesses lumped together by common symptoms but separated by uncommon pathophysiologies. The example of chronic fatigue syndrome (CFS) is instructive. There is evidence to support all three models of understanding. Three recent large studies have suggested that FSSs are both similar and dissimilar at the same time. The solution to the debate is that we need to both “lump” and “split.” We need to study both the similarities between syndromes and their dissimilarities to better understand what we currently call the FSSs.

Copyright 2010 Elsevier Inc. All rights reserved.

 

Source: White PD. Chronic fatigue syndrome: Is it one discrete syndrome or many? Implications for the “one vs. many” functional somatic syndromes debate. J Psychosom Res. 2010 May;68(5):455-9. doi: 10.1016/j.jpsychores.2010.01.008. Epub 2010 Mar 17. https://www.ncbi.nlm.nih.gov/pubmed/20403504

 

One single diagnosis, bodily distress syndrome, succeeded to capture 10 diagnostic categories of functional somatic syndromes and somatoform disorders

Abstract:

BACKGROUND: In order to clarify the classification of physical complaints not attributable to verifiable, conventionally defined diseases, a new diagnosis of bodily distress syndrome was introduced. The aim of this study was to test if patients diagnosed with one of six different functional somatic syndromes or a DSM-IV somatoform disorder characterized by physical symptoms were captured by the new diagnosis.

METHOD: A stratified sample of 978 consecutive patients from neurological (n=120) and medical (n=157) departments and from primary care (n=701) was examined applying post-hoc diagnoses based on the Schedules for Clinical Assessment in Neuropsychiatry diagnostic instrument. Diagnoses were assigned only to clinically relevant cases, i.e., patients with impairing illness.

RESULTS: Bodily distress syndrome included all patients with fibromyalgia (n=58); chronic fatigue syndrome (n=54) and hyperventilation syndrome (n=49); 98% of those with irritable bowel syndrome (n=43); and at least 90% of patients with noncardiac chest pain (n=129), pain syndrome (n=130), or any somatoform disorder (n=178). The overall agreement of bodily distress syndrome with any of these diagnostic categories was 95% (95% CI 93.1-96.0; kappa 0.86, P<.0001). Symptom profiles of bodily distress syndrome organ subtypes were similar to those of the corresponding functional somatic syndromes with diagnostic agreement ranging from 90% to 95%.

CONCLUSION: Bodily distress syndrome seem to cover most of the relevant “somatoform” or “functional” syndromes presenting with physical symptoms, not explained by well-recognized medical illness, thereby offering a common ground for the understanding of functional somatic symptoms. This may help unifying research efforts across medical disciplines and facilitate delivery of evidence-based care.

Copyright 2010 Elsevier Inc. All rights reserved.

 

Source: Fink P, Schröder A. One single diagnosis, bodily distress syndrome, succeeded to capture 10 diagnostic categories of functional somatic syndromes and somatoform disorders. J Psychosom Res. 2010 May;68(5):415-26. doi: 10.1016/j.jpsychores.2010.02.004. https://www.ncbi.nlm.nih.gov/pubmed/20403500

 

The prognosis of different fatigue diagnostic labels: a longitudinal survey

Abstract:

BACKGROUND: Several different diagnostic labels exist for the fatigue syndromes, including chronic fatigue syndrome (CFS), myalgic encephalomyelitis (ME) and postviral fatigue syndrome (PVFS). An allied condition is fibromyalgia. No study has examined prognostic differences across these different labels.

OBJECTIVE: To compare the prognoses of patients labelled with different fatigue syndromes in primary care.

METHODS: We performed a longitudinal survey, using electronic records from the General Practice Research Database. All 18,122 patients diagnosed by their GP with a fatigue syndrome from 1988-2001 with a minimum of one year of records after diagnosis were collated into four groups: CFS, ME, PVFS and fibromyalgia. CFS and ME were combined for the main analysis as no code for CFS was available until 1995. The length of illness was calculated as the interval between the diagnosis and the last recorded fatigue symptom, expressed as days per year, to account for differing lengths of record after diagnosis.

RESULTS: Patients with CFS/ME combined had a worse prognosis (median length of illness 80 days per year; interquartile range 0-242) than fibromyalgia (51; 0-244) or PVFS 0 (0-108), a significant difference, P < 0.001. In a subgroup analysis, ME had a worse prognosis (median length of illness in days per year 106; interquartile range 0-259) than CFS (33; 0-170), P < 0.001, in spite of a better course before diagnosis. Secondary outcome measures were consistent with these results.

CONCLUSION: There were important differences in outcome between the various fatigue labels, with ME having the worst prognosis and PVFS the best. This could be an adverse effect of the label ME itself. Alternatively, patients who are destined to have a worse prognosis may preferentially attract the ME label. Our data support the first interpretation.

 

Source: Hamilton WT, Gallagher AM, Thomas JM, White PD. The prognosis of different fatigue diagnostic labels: a longitudinal survey. Fam Pract. 2005 Aug;22(4):383-8. Epub 2005 Apr 1. http://fampra.oxfordjournals.org/content/22/4/383.long (Full article)

 

Incidence of fatigue symptoms and diagnoses presenting in UK primary care from 1990 to 2001

Erratum in: J R Soc Med. 2005 Feb;98(2):88.

 

Abstract:

Little is known about whether the incidence of symptoms of fatigue presented in primary care, and the consequent diagnoses made, change over time. The UK General Practice Research Database was used to investigate the annual incidence of both fatigue symptoms and diagnoses recorded in UK primary care from 1990 to 2001. The overall incidence of all fatigue diagnoses decreased from 87 per 100 000 patients in 1990 to 49 in 2001, a reduction of 44%, while postviral fatigue syndromes decreased from 81% of all fatigue diagnoses in 1990 to 60% in 2001. Chronic fatigue syndrome (CFS) and myalgic encephalomyelitis (ME) together increased from 9% to 26% of all fatigue diagnoses. The incidence of fibromyalgia increased from less than 1 per 100 000 to 35 per 100 000. In contrast, there was no consistent change in the incidence of all recorded symptoms of fatigue, with an average of 1503 per 100 000, equivalent to 1.5% per year. CFS/ME and fibromyalgia were rarely diagnosed in children and were uncommon in the elderly. All symptoms and diagnoses were more common in females than in males. The overall incidence of fatigue diagnoses in general has fallen, but the incidence rates of the specific diagnoses of CFS/ME and fibromyalgia have risen, against a background of little change in symptom reporting. This is likely to reflect fashions in diagnostic labelling rather than true changes in incidence.

Comment in: Brain imaging in fatigue syndromes. [J R Soc Med. 2005]

 

Source: Gallagher AM, Thomas JM, Hamilton WT, White PD. Incidence of fatigue symptoms and diagnoses presenting in UK primary care from 1990 to 2001. J R Soc Med. 2004 Dec;97(12):571-5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1079668/ (Full article)

 

Exhaustion–not fatigue

Erlend Hem & Jon Håvard Loge refutes the language gap in this Journal no. 18/2004 our argument that “chronic  exhaustion syndrome” should be the Norwegian term for “chronic fatigue syndrome” ( 1 , 2 ). In his speech, they write that “many patients with somatic diseases and fatigue would probably feel somewhat alien to mention symptom as fatigue, because fatigue usually linked to a prior activity” ( 2 ).

You can read the rest of this comment here: http://tidsskriftet.no/article/1095666

 

Source: Wyller VB, Wyller TB. Exhaustion–not fatigue. Tidsskr Nor Laegeforen. 2004 Nov 4;124(21):2802; author reply 2802. [Article in Norwegian] http://tidsskriftet.no/article/1095666 (Full article)

 

Chronic fatigue syndrome versus neuroendocrineimmune dysfunction syndrome:differential attributions

Abstract:

Since 1988, when the term chronic fatigue syndrome (CFS) was coined, considerable discussion has occurred about stigma associated with this diagnostic term. In particular, patients with CFS have felt that this term trivializes the serious nature of this disorder. A Name Change Work group, appointed by the CFS Coordinating Committee, developed an umbrella term: chronic neuroendocrineimmune dysfunction syndrome (CNDS), and proposed that there would be sub-types under this term, one being CFS. The present study examined attributions of this new umbrella term when compared with CFS.

Nurses and physician assistants (PAs) were presented a case study of a patient with symptoms of CFS. They were told that the patient had either “chronic fatigue syndrome,” “chronic neuroendocrineimmune dysfunction syndrome,” or “chronic neuroendocrineimmune dysfunction syndrome, which had formerly been called chronic fatigue syndrome.” The different terms led to different attributions, with PA respondents rating the “CNDS” label as more severe. Results suggest that a more medical sounding term (CNDS) may lead to attributions that this syndrome is a more serious, disabling illness. The policy implications of these findings are discussed.

 

Source: Jason LA, Holbert C, Torres-Harding S, Taylor RR, LeVasseur JJ, Breitinger P, LaBarbera D, Siegel L. Chronic fatigue syndrome versus neuroendocrineimmune dysfunction syndrome:differential attributions. J Health Soc Policy. 2003;18(1):43-55. http://www.ncbi.nlm.nih.gov/pubmed/15189800

 

Evaluating attributions for an illness based upon the name: chronic fatigue syndrome, myalgic encephalopathy and Florence Nightingale disease

Abstract:

In recent years, considerable discussion has occurred about stigma surrounding the name given to an illness currently known as chronic fatigue syndrome (CFS). Although patients and medical personnel have expressed varying opinions on this issue, no studies have evaluated how beliefs about the illness change based upon the type of name used for diagnostic purposes. Proposals have been put forth to rename the illness with an eponym (a famous patient’s or researcher’s name) or with a less trivial sounding, more medically based type of name.

In this study, attributions about CFS were measured in three groups of medical trainees. All groups read the same case study of a person with classic symptoms of chronic fatigue syndrome, with the only difference being in the type of name given. Trainees then were asked to provide attributions about certain aspects of the illness, including its cause, severity, and prognosis.

Results suggested that, across name conditions, most trainees appeared to consider the symptom complex of CFS a serious illness resulting in poor quality of life. In addition, findings indicated that the name, chronic fatigue syndrome, may be regarded less seriously than the Myalgic Encephalopathy name with respect to some important aspects of the illness. In this study, specialty of medical trainee also played a role in how the illness was perceived.

 

Source: Jason LA, Taylor RR, Plioplys S, Stepanek Z, Shlaes J. Evaluating attributions for an illness based upon the name: chronic fatigue syndrome, myalgic encephalopathy and Florence Nightingale disease. Am J Community Psychol. 2002 Feb;30(1):133-48. http://www.ncbi.nlm.nih.gov/pubmed/11928774

 

Assessing attitudes toward new names for chronic fatigue syndrome

Abstract:

A questionnaire was distributed at the American Association of Chronic Fatigue Syndrome’s biannual convention in Washington in January 2001 as well as through various Internet Web sites and listserves during early February and March of 2001. The sample consisted of 432 respondents. Most respondents (86%) indicated they wanted a name change, although more patients than scientists were in favor of this change. It was also apparent that the patients and physicians were clearly split between adopting a name such as myalgic encephalopathy versus one such as neuro-endocrine immune disorder. Also, among those respondents who selected either of these two choices for a new name, less than 30% of them supported the other name. Although the majority of respondents feel the name should be changed at this time, this survey suggests there are different stakeholders involved in the name-change process, each with strong and sometimes disparate feelings about changing the name.

 

Source: Jason LA, Eisele H, Taylor RR. Assessing attitudes toward new names for chronic fatigue syndrome. Eval Health Prof. 2001 Dec;24(4):424-35. http://www.ncbi.nlm.nih.gov/pubmed/11817200

 

Attitudes regarding chronic fatigue syndrome: the importance of a name

Abstract:

Undergraduates from diverse academic backgrounds and medical trainees were assessed regarding their attitudes about and familiarity with chronic fatigue syndrome (CFS). We explored whether different names given to chronic fatigue syndrome (CFS, myalgic encephalopathy, or Florence Nightingale disease) were associated with differences in attributions regarding its cause, nature, severity, contagion, prognosis, and treatment. Participants’ attributions toward the illness varied with the names used to characterize it.

Participants prompted with the myalgic encephalopathy name were more likely to attribute a biomedical cause to the illness, and less likely to consider patients as candidates for organ donation than those prompted with the CFS name. Although the medical trainees were less likely to consider the patient as malingering, and more likely to view the illness as leading to poorer quality of life and a poorer prognosis, they were also more likely to consider the illness a form of primary depression, more likely to think the patient would attempt suicide, and less likely to consider associated cognitive symptoms as severe. The implications are discussed.

 

Source: Jason LA, Taylor RR, Stepanek Z, Plioplys S. Attitudes regarding chronic fatigue syndrome: the importance of a name. J Health Psychol. 2001 Jan;6(1):61-71. Doi: 10.1177/135910530100600105. http://www.ncbi.nlm.nih.gov/pubmed/22049238