Category: Case Definition

A Chronic Fatigue Syndrome (CFS) severity score based on case designation criteria

Abstract:

BACKGROUND: Chronic Fatigue Syndrome case designation criteria are scored as physicians’ subjective, nominal interpretations of patient fatigue, pain (headaches, myalgia, arthralgia, sore throat and lymph nodes), cognitive dysfunction, sleep and exertional exhaustion.

METHODS: Subjects self-reported symptoms using an anchored ordinal scale of 0 (no symptom), 1 (trivial complaints), 2 (mild), 3 (moderate), and 4 (severe). Fatigue of 3 or 4 distinguished “Fatigued” from “Not Fatigued” subjects. The sum of the 8(Sum8) ancillary criteria was tested as a proxy for fatigue. All subjects had history and physical examinations to exclude medical fatigue, and ensure categorization as healthy or CFS subjects.

RESULTS: Fatigued subjects were divided into CFS with ≥4 symptoms or Chronic Idiopathic Fatigue (CIF) with ≤3 symptoms. ROC of Sum8 for CFS and Not Fatigued subjects generated a threshold of 14 (specificity=0.934; sensitivity=0.928). CFS (n=256) and CIF (n=55) criteria were refined to include Sum8≥14 and ≤13, respectively. Not Fatigued subjects had highly skewed Sum8 responses. Healthy Controls (HC; n=269) were defined by fatigue≤2 and Sum8≤13. Those with Sum8≥14 were defined as CFS-Like With Insufficient Fatigue Syndrome (CFSLWIFS; n=20). Sum8 and Fatigue were highly correlated (R(2)=0.977; Cronbach’s alpha=0.924) indicating an intimate relationship between symptom constructs. Cluster analysis suggested 4 clades each in CFS and HC. Translational utility was inferred from the clustering of proteomics from cerebrospinal fluid.

CONCLUSIONS: Plotting Fatigue severity versus Sum8 produced an internally consistent classifying system. This is a necessary step for translating symptom profiles into fatigue phenotypes and their pathophysiological mechanisms.

 

Source: Baraniuk JN, Adewuyi O, Merck SJ, Ali M, Ravindran MK, Timbol CR, Rayhan R, Zheng Y, Le U, Esteitie R, Petrie KN. A Chronic Fatigue Syndrome (CFS) severity score based on case designation criteria. Am J Transl Res. 2013;5(1):53-68. Epub 2013 Jan 21. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3560481/ (Full article)

 

Relationship between autonomic cardiovascular control, case definition, clinical symptoms, and functional disability in adolescent chronic fatigue syndrome: an exploratory study

Abstract:

Chronic Fatigue Syndrome (CFS) is characterized by severe impairment and multiple symptoms. Autonomic dysregulation has been demonstrated in several studies. We aimed at exploring the relationship between indices of autonomic cardiovascular control, the case definition from Centers for Disease Control and Prevention (CDC criteria), important clinical symptoms, and disability in adolescent chronic fatigue syndrome.

38 CFS patients aged 12-18 years were recruited according to a wide case definition (ie. not requiring accompanying symptoms) and subjected to head-up tilt test (HUT) and a questionnaire. The relationships between variables were explored with multiple linear regression analyses. In the final models, disability was positively associated with symptoms of cognitive impairments (p<0.001), hypersensitivity (p<0.001), fatigue (p=0.003) and age (p=0.007).

Symptoms of cognitive impairments were associated with age (p=0.002), heart rate (HR) at baseline (p=0.01), and HR response during HUT (p=0.02). Hypersensitivity was associated with HR response during HUT (p=0.001), high-frequency variability of heart rate (HF-RRI) at baseline (p=0.05), and adherence to the CDC criteria (p=0.005). Fatigue was associated with gender (p=0.007) and adherence to the CDC criteria (p=0.04).

In conclusion, a) The disability of CFS patients is not only related to fatigue but to other symptoms as well; b) Altered cardiovascular autonomic control is associated with certain symptoms; c) The CDC criteria are poorly associated with disability, symptoms, and indices of altered autonomic nervous activity.

 

Source: Wyller VB, Helland IB. Relationship between autonomic cardiovascular control, case definition, clinical symptoms, and functional disability in adolescent chronic fatigue syndrome: an exploratory study. Biopsychosoc Med. 2013 Feb 7;7(1):5. doi: 10.1186/1751-0759-7-5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3570350/ (Full article)

 

Myalgic Encephalomyelitis (ME), Chronic Fatigue Syndrome (CFS), and Chronic Fatigue (CF) are distinguished accurately: results of supervised learning techniques applied on clinical and inflammatory data

Abstract:

There is much debate on the diagnostic classification of Myalgic Encephalomyelitis (ME), Chronic Fatigue Syndrome (CFS) and chronic fatigue (CF). Post-exertional malaise (PEM) is stressed as a key feature. This study examines whether CF and CFS, with and without PEM, are distinct diagnostic categories.

Fukuda’s criteria were used to diagnose 144 patients with chronic fatigue and identify patients with CFS and CF, i.e. those not fulfilling the Fukuda’s criteria. PEM was rated by means of a scale with defined scale steps between 0 and 6. CFS patients were divided into those with PEM lasting more than 24h (labeled: ME) and without PEM (labeled: CFS). The 12-item Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale was used to measure severity of illness. Plasma interleukin-1 (IL-1), tumor necrosis factor (TNF)α, and lysozyme, and serum neopterin were employed as external validating criteria.

Using fatigue, a subjective feeling of infection and PEM we found that ME, CFS, and CF were distinct categories. Patients with ME had significantly higher scores on concentration difficulties and a subjective experience of infection, and higher levels of IL-1, TNFα, and neopterin than patients with CFS. These biomarkers were significantly higher in ME and CFS than in CF patients. PEM loaded highly on the first two factors subtracted from the data set, i.e. “malaise-sickness” and “malaise-hyperalgesia”. Fukuda’s criteria are adequate to make a distinction between ME/CFS and CF, but ME/CFS patients should be subdivided into ME (with PEM) and CFS (without PEM).

Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

 

Source: Maes M, Twisk FN, Johnson C. Myalgic Encephalomyelitis (ME), Chronic Fatigue Syndrome (CFS), and Chronic Fatigue (CF) are distinguished accurately: results of supervised learning techniques applied on clinical and inflammatory data. Psychiatry Res. 2012 Dec 30;200(2-3):754-60. doi: 10.1016/j.psychres.2012.03.031. Epub 2012 Apr 21. https://www.ncbi.nlm.nih.gov/pubmed/22521895

 

Response to ‘A controversial consensus’; by the International Consensus Panel

Dear Sir,First and foremost, we would like to thank Drs van der Meer and Lloyd [1] for their careful and thorough review of the International Consensus Criteria (ICC) paper [2]. We support this type of open discussion and strongly agree that only in this way will the basic and clinical science of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS) evolve soundly. This being said the content of their feedback also leads us to believe that several elements have been taken out of context or that we may not have articulated these components as well as we had hoped. As a result, we fully appreciate this opportunity to rectify any such miscommunication.

You can read the rest of this comment here: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2011.02499.x/full

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

 

Source: Broderick G. Response to ‘A controversial consensus’; by the International Consensus Panel. J Intern Med. 2012 Feb;271(2):213-7. doi: 10.1111/j.1365-2796.2011.02499.x. Epub 2011 Dec 30. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2011.02499.x/full (Full article)

 

Contrasting case definitions for chronic fatigue syndrome, Myalgic Encephalomyelitis/chronic fatigue syndrome and myalgic encephalomyelitis

Abstract:

This article uses data from patients recruited using the 1994 case definition of chronic fatigue syndrome (CFS) to contrast those meeting criteria for the Myalgic Encephalomyelitis/chronic fatigue syndrome (ME/CFS) Canadian case definition with those that did not meet these criteria. The study also contrasts those meeting criteria for Myalgic Encephalomyelitis (ME) based on criteria from Ramsay and other theorists with those that did not meet the ME criteria. The ME/CFS case definition criteria identified a subset of patients with more functional impairments and physical, mental, and cognitive problems than the subset not meeting these criteria. The ME subset had more functional impairments, and more severe physical and cognitive symptoms than the subset not meeting ME criteria. When applied to a population meeting the 1994 CFS case definition, both ME/CFS and ME criteria appear to select a more severe subset of patients.

 

Source: Jason LA, Brown A, Clyne E, Bartgis L, Evans M, Brown M. Contrasting case definitions for chronic fatigue syndrome, Myalgic Encephalomyelitis/chronic fatigue syndrome and myalgic encephalomyelitis. Eval Health Prof. 2012 Sep;35(3):280-304. doi: 10.1177/0163278711424281. Epub 2011 Dec 7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3658447/ (Full article)

 

Data mining: comparing the empiric CFS to the Canadian ME/CFS case definition

Abstract:

This article contrasts two case definitions for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). We compared the empiric CFS case definition (Reeves et al., 2005) and the Canadian ME/CFS clinical case definition (Carruthers et al., 2003) with a sample of individuals with CFS versus those without. Data mining with decision trees was used to identify the best items to identify patients with CFS. Data mining is a statistical technique that was used to help determine which of the survey questions were most effective for accurately classifying cases. The empiric criteria identified about 79% of patients with CFS and the Canadian criteria identified 87% of patients. Items identified by the Canadian criteria had more construct validity. The implications of these findings are discussed.

© 2011 Wiley Periodicals, Inc.

 

Source: Jason LA, Skendrovic B, Furst J, Brown A, Weng A, Bronikowski C. Data mining: comparing the empiric CFS to the Canadian ME/CFS case definition. J Clin Psychol. 2012 Jan;68(1):41-9. doi: 10.1002/jclp.20827. Epub 2011 Aug 5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3228898/ (Full article)

 

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 in an ethnically diverse population: the influence of psychosocial adversity and physical inactivity

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a complex multifactorial disorder. This paper reports the prevalence of chronic fatigue (CF) and CFS in an ethnically diverse population sample and tests whether prevalence varies by social adversity, social support, physical inactivity, anxiety and depression.

METHODS: Analysis of survey data linking the Health Survey for England (1998 and 1999) and the Ethnic Minority Psychiatric Illness Rates in the Community (EMPIRIC) study undertaken in 2000. The study population comprised a national population sample of 4,281 people ages 16 to 74 years. CF and CFS were operationally defined on the basis of an interview in the EMPIRIC study, alongside questions about psychosocial risk factors. Previous illnesses were reported in the Health Survey for England during 1998 and 1999, as was physical inactivity.

RESULTS: All ethnic minority groups had a higher prevalence of CFS than the White group. The lowest prevalence was 0.8% in the White group, and it was highest at 3.5% in the Pakistani group (odds ratio (OR), 4.1; 95% confidence interval (95% CI), 1.6 to 10.4). Anxiety (OR, 1.8; 95% CI, 1.4 to 2.2), depression (OR, 1.4; 95% CI, 1.1 to 1.8), physical inactivity (OR, 2.0; 95% CI, 1.1 to 3.8), social strain (OR, 1.24; 95% CI, 1.04 to 1.48) and negative aspects of social support (OR, 2.12; 95% CI, 1.4 to 3.3) were independent risk factors for CFS in the overall sample. Together these risk factors explained ethnic differences in the prevalence of CFS, but no single risk factor could explain a higher prevalence in all ethnic groups.

CONCLUSIONS: The prevalence of CFS, but not CF, varies by ethnic group. Anxiety, depression, physical inactivity, social strain and negative aspects of social support together accounted for prevalence differences of CFS in the overall sample.

 

Source: Bhui KS, Dinos S, Ashby D, Nazroo J, Wessely S, White PD. Chronic fatigue syndrome in an ethnically diverse population: the influence of psychosocial adversity and physical inactivity. BMC Med. 2011 Mar 21;9:26. doi: 10.1186/1741-7015-9-26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3072345/ (Full article)

 

A review of the definitional criteria for chronic fatigue syndrome

Abstract:

RATIONALE, AIMS AND OBJECTIVES: The research community has for more than three decades tried to unravel the diagnostic mystery that is Chronic Fatigue Syndrome (CFS). This has resulted in considerable amounts of time and money being invested in attempts aimed at establishing the aetiology and pathogenesis of CFS. All of this investment has produced evidence of an interesting variety of endocrine, immune, infectious, muscular and neurological abnormalities in CFS; however, the cause remains elusive. The absence of a known causative agent or diagnostic test for CFS has resulted in the development of a number of CFS case definitions. As such, the main objectives of this paper are to provide a critical review of the similarities and differences between the varying approaches to CFS case definition. The conflicts and controversies that have emerged as a result of the differing definitional criterion for CFS are highlighted and the potential impact on future research is identified.

METHODS, RESULTS AND CONCLUSIONS: This paper presents a critical review of the most frequently used case definitions in CFS. There are currently five case definitions of CFS; however, the most prominent and widely used of these definitions is the 1994 Centre for Disease Control and Prevention Case Definitions. However, the pre-eminence of this definition over the others has never been substantiated and it has been widely criticized for its lack of specificity. Furthermore, none of the above case definitions have produced evidence to demonstrate their accuracy or precision at defining cases of CFS. A summary description of the symptom profile included in each of the case definitions is provided. The inconsistencies that have emerged in CFS research as a consequence of differing approaches to case definition are also highlighted and discussed.

© 2010 Blackwell Publishing Ltd.

 

Source: Christley Y, Duffy T, Martin CR. A review of the definitional criteria for chronic fatigue syndrome. J Eval Clin Pract. 2012 Feb;18(1):25-31. doi: 10.1111/j.1365-2753.2010.01512.x. Epub 2010 Oct 4. https://www.ncbi.nlm.nih.gov/pubmed/21029269

 

Severe versus Moderate criteria for the new pediatric case definition for ME/CFS

Abstract:

The new diagnostic criteria for pediatric ME/CFS are structurally based on the Canadian Clinical Adult case definition, and have more required specific symptoms than the (Fukuda et al. Ann Intern Med 121:953-959, 1994) adult case definition.

Physicians specializing in pediatric ME/CFS referred thirty-three pediatric patients with ME/CFS and 21 youth without the illness. Those who met ME/CFS criteria were separated into Severe and Moderate categories. Significant differences were found for symptoms within each of the six major categories: fatigue, post-exertional malaise, sleep, pain, neurocognitive difficulties, and autonomic/neuroendocrine/immune manifestations.

In general, the results showed participants who met the Severe ME/CFS criteria reported the highest scores, the Moderate ME/CFS group show scores that were a little lower, and the control group evidenced the lowest scores. Findings indicate that the Pediatric Case Definition for ME/CFS can distinguish between those with this illness and controls, and between those with Severe versus Moderate manifestations of the illness.

 

Source: Jason L, Porter N, Shelleby E, Till L, Bell DS, Lapp CW, Rowe K, De Meirleir K. Severe versus Moderate criteria for the new pediatric case definition for ME/CFS. Child Psychiatry Hum Dev. 2009 Dec;40(4):609-20. doi: 10.1007/s10578-009-0147-8. Epub 2009 Jun 10.https://www.ncbi.nlm.nih.gov/pubmed/19513826