Clinical criteria versus a possible research case definition in chronic fatigue syndrome/myalgic encephalomyelitis

Abstract

Background The Institute of Medicine (IOM) recently developed clinical criteria for what had been known as chronic fatigue syndrome (CFS). Given the broad nature of the clinical IOM criteria, there is a need for a research definition that would select a more homogenous and impaired group of patients than the IOM clinical criteria. At the present time, it is unclear what will serve as the research definition. Purpose The current study focused on a research definition which selected homebound individuals who met the four IOM criteria, excluding medical and psychiatric co-morbidities. Methods Our research criteria were compared to those participants meeting the IOM criteria. Those not meeting either of these criteria sets were placed in a separate group defined by 6 or more months of fatigue. Data analyzed were from the DePaul Symptom Questionnaire and the SF-36. Due to unequal sample sizes and variances, Welch’s F tests and Games-Howell post hoc tests were conducted. Results Using a large database of over 1,000 patients from several countries, we found that those meeting a more restrictive research definition were even more impaired and more symptomatic than those meeting criteria for the other two groups. Conclusion Deciding on a particular research case definition would allow researchers to select more comparable patient samples across settings, and this would represent one of the most significant methodologic advances for this field of study.

A Brief Questionnaire to Assess Post-Exertional Malaise

“…Obtaining in-person physician diagnoses would have strengthened this study. In addition, some consider ME and CFS two distinct illness [18], whereas others have suggested that it might be difficult to separate these two illnesses [19,20,21]. If there are two illnesses, then collapsing groups would complicate interpretations of the results.…”

The Development of the DePaul Symptom Questionnaire: Original, Expanded, Brief, and Pediatric Versions

“…As an example, Jason et al ( 63 ) suggested the following classification system, those with just chronic fatigue of 6 or more months would be the broadest category (similar to the Oxford criteria), those who meet a ME/CFS clinical criteria would be represented by the IOM ( 6 ) criteria (with few exclusionary illnesses), and a purer ME criteria could be based either on the Canadian Consensus Criteria ( 3 ) or work of Ramsay ( 36 ). Sophisticated and methodologically sound research methods could also be used to select and operationalize criteria for a research case definition ( 22 , 31 , 32 , 64 ).…”

Impact of Polypharmacy on Candidate Biomarker miRNomes for the Diagnosis of Fibromyalgia and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Striking back on Treatments

“…Fibromyalgia (FM) is a debilitating disorder characterized by low pain threshold and muscle tenderness accompanied by bowel abnormalities, sleep disturbances, depressive episodes, cognitive problems and chronic pain [1][2][3][4]. Despite commonly comorbid with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a disease also showing a complex clinical pathophysiology [5][6][7][8][9][10][11], these syndromes have been classified by the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) with separate codes (M79.7 and R53.82 or G93.3 if post-viral, for FM and ME/CFS respectively) [12]. However, disease distinctions remain under debate [5].…”