A definition of recovery in myalgic encephalomyelitis and chronic fatigue syndrome should be based upon objective measures

Introduction

Adamowicz and colleagues recently proposed to use “a consistent definition of recovery that captures a broad-based return to health with assessments of both fatigue and function as well as the patients’ perceptions of his/her recovery status” for patients with chronic fatigue syndrome (CFS).

Methods

A qualitative analysis of case definitions for Myalgic encephalomyelitis (ME) and CFS and methods to assess the symptoms and clinical status of ME and CFS patients objectively.

Results

The criteria of CFS define a heterogeneous disorder. ME, often used interchangeably with CFS, is principally defined by muscle weakness, cognitive impairment etc., but above all post-exertional “malaise”: a long-lasting increase in symptoms, e.g. muscle pain and cognitive deficits, after a minor exertion. The principle symptom of CFS however is “chronic fatigue”. Since post-exertional “malaise” is not obligatory for CFS, only part of the CFS patients meet the diagnostic criteria for ME, while not all ME patients qualify as CFS patients. There are several accepted methods to assess characteristic symptoms and the clinical status of ME and CFS patients using objective measures, e.g. (repeated) cardiopulmonary exercise tests.

Conclusion

To resolve the debate about the clinical status, proposed effectiveness of therapies and recovery in ME and CFS, it is crucial to accurately diagnose patients using well-defined criteria for ME and CFS and an objective assessment of various typical symptoms, since subjective measures such as “fatigue” will perpetuate the debate.     

Idiopathic chronic fatigue and chronic fatigue syndrome: a comparison of two case-definitions

The aim of the study was to compare the signs and symptoms of individuals meeting two different definitions of chronic fatigue syndrome (CFS). Ninety-four patients fitting the eligibility criteria for idiopathic fatigue were enrolled into the study. Of the 94 patients, 48 met the 1988 definition of CFS, 20 the 1994 (but not the 1988) definition of CFS, and 26 met neither definition. The 1994 defined cases were more likely than 1988 defined cases, and non-syndromal individuals to be male, married, and high school educated. The 1994 cases were less likely than 1988 cases to present acute onset, self reported sore throat, mild fever lymphadenopathy, pharyngitis. In conclusion, the 1994 criteria increased the number of patients classified as CFS; however, those who fit only the 1994 criteria were less likely to have an acute symptomatic onset and signs and symptoms suggestive of an infectious process.     

Health-related quality of life in patients with myalgic encephalomyelitis/chronic fatigue syndrome: an Australian cross-sectional study

Quality of Life Research - Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious and debilitating disorder associated with significant disruptions in daily life including. This...     

Variability in diagnostic criteria for chronic fatigue syndrome may result in substantial differences in patterns of symptoms and disability

Chronic fatigue syndrome (CFS) is an illness that involves severe, prolonged exhaustion as well as neurologic, immunologic, and endocrine system pathology. Because the pathogenesis of CFS has yet to be determined, case definitions have relied on clinical observation in classifying signs and symptoms for diagnosis. The current investigation examined differences between CFS as defined by Fukuda and colleagues and a set of criteria that has been stipulated for myalgic encephalomyelitis (ME). Dependent measures included psychiatric comorbidity, symptom frequency, symptom severity, and functional impairment. The ME and Fukuda et al. (1994) CFS criteria were compared with a group having chronic fatigue due to psychiatric reasons. Significant differences occurred primarily with neurologic, neuropsychiatric, fatigue/weakness, and rheumatological symptoms. These findings suggest that it might be inappropriate to synthesize results from studies of this illness that use different definitions to select study populations.     

Specifics of chronic fatigue syndrome coping strategies identified in a French flash survey during the COVID-19 containment

The COVID-19 pandemic has focused health systems on supporting patients affected by this virus. Meanwhile in the community, many other contained patients could only use self-care strategies, especially in countries that have set up a long and strict containment such as France. The study aimed to compare coping strategies deployed by patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS; a poorly recognised syndrome) to those with better known and referenced chronic conditions. An online flash survey was conducted during the containment period in partnership with French Patients Organizations including ME/CFS national association. Therefore, ‘Brief COPE’ version of Lazarus and Folkman's Ways of Coping Check List has been adapted to the specificity of the containment. The survey was e-distributed in France from 15 April to 11 May 2020. Differences of coping strategies were analyzed using Wilcoxon–Mann–Withney test. Amongst 637 responses, 192 were complete, presenting a wide variety of diseases, including 93 ME/CFS. The latter have significantly different coping strategies than recognised diagnosed diseases patients: similar uses of emotion focused coping but less uses of seek social support and problem-focused copings. In conclusion, coping strategies are different for those who deal with the daily experience of ME/CFS, highly disabling chronic condition with diagnostic ambiguity, low degree of medical and social recognition and without treatment. Better understanding of those strategies is needed to provide the means for health promotion researchers, managers and clinicians, to accompany those patients.     

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms

Although myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) are considered to be synonymous, the definitional criteria for ME and CFS define two distinct, partially overlapping, clinical entities. ME, whether defined by the original criteria or by the recently proposed criteria, is not equivalent to CFS, let alone a severe variant of incapacitating chronic fatigue. Distinctive features of ME are: muscle weakness and easy muscle fatigability, cognitive impairment, circulatory deficits, a marked variability of the symptoms in presence and severity, but above all, post-exertional “malaise”: a (delayed) prolonged aggravation of symptoms after a minor exertion. In contrast, CFS is primarily defined by (unexplained) chronic fatigue, which should be accompanied by four out of a list of 8 symptoms, e.g., headaches. Due to the subjective nature of several symptoms of ME and CFS, researchers and clinicians have questioned the physiological origin of these symptoms and qualified ME and CFS as functional somatic syndromes. However, various characteristic symptoms, e.g., post-exertional “malaise” and muscle weakness, can be assessed objectively using well-accepted methods, e.g., cardiopulmonary exercise tests and cognitive tests. The objective measures acquired by these methods should be used to accurately diagnose patients, to evaluate the severity and impact of the illness objectively and to assess the positive and negative effects of proposed therapies impartially.     

Neurocognitive complaints and functional status among patients with chronic fatigue syndrome and fibromyalgia

Purpose

The purpose of this study was to conduct a longitudinal examination of cognitive complaints and functional status in patients with chronic fatigue syndrome (CFS) alone and those who also had fibromyalgia (CFS/FM).

Methods

A total of 93 patients from a tertiary care fatigue clinic were evaluated on four occasions, each 6 months apart. Each evaluation included a tender point assessment, and self-reported functional status and cognitive complaints.

Results

Patients with CFS/FM reported significantly worse physical functioning, more bodily pain, and more cognitive difficulties (visuo-perceptual ability and verbal memory) than patients with CFS alone. Over time, bodily pain decreased only for participants with CFS alone. Verbal memory problems were associated with more bodily pain for both patient groups, whereas visuo-perceptual problems were associated with worse functional status for patients with CFS alone.

Conclusions

This study adds to the literature on functional status, longitudinal course, and cognitive difficulties among patients with CFS and those with CFS and FM. The results suggest that patients with CFS/FM are more disabled, have more cognitive complaints, and improve more slowly over time than patients with CFS alone. Specific cognitive difficulties are related to worse functional status, which supports the addition of cognitive difficulties to the FM case criteria.

     

The lifestyle of patients with chronic fatigue syndrome and the effect on fatigue and functional impairments

Background:  Little is known about the lifestyle of patients with chronic fatigue syndrome (CFS) and its influence on symptoms of CFS. The present study aimed to investigate the lifestyle of patients with CFS, and to assess whether lifestyle factors are related to fatigue and functional impairments.
Methods:  Two hundred and forty-seven patients fulfilling the Center for Disease Control criteria for CFS were included. Validated questionnaires were used to collect data on lifestyle factors, smoking, intake of alcohol, fat, fibres, fruit and vegetables, body mass index (BMI), fatigue severity and functional impairments.
Results:  Of the CFS patients, 23% smoked, 32% had an unhealthy BMI, and none had an unhealthy alcohol intake. A majority had an unhealthy food intake: 70% had unhealthy fat, fruit and vegetable intake, and 95% had unhealthy fibre intake. Compared with the general Dutch population, significantly fewer CFS patients were overweight. Significantly more female CFS patients abstained from alcohol, and fewer male CFS patients smoked. Unhealthy lifestyle factors were not significantly associated with fatigue severity or functional impairments.
Conclusions:  CFS patients tend to lead a healthier lifestyle compared to the general Dutch population. However, no relationship was found between lifestyle factors and fatigue severity and functional impairments in CFS.     

A systematic review describing the prognosis of chronic fatigue syndrome

AIM: To perform a systematic review of studies describing the prognosis of chronic fatigue (CF) and chronic fatigue syndrome (CFS) and to identify occupational outcomes from such studies. METHOD: A literature search was used to identify all studies describing the clinical follow-up of patients following a diagnosis of CF or CFS. The prognosis is described in terms of the proportion of individuals improved during the period of follow-up. Return to work, other medical illnesses and death as outcomes are also considered, as are variables which may influence prognosis. RESULTS: Twenty-eight articles met the inclusion criteria and, for the 14 studies of subjects meeting operational criteria for CFS, the median full recovery rate was 5% (range 0-31%) and the median proportion of patients who improved during follow-up was 39.5% (range 8-63%). Less fatigue severity at baseline, a sense of control over symptoms and not attributing illness to a physical cause were all associated with a good outcome. Return to work at follow-up ranged from 8 to 30% in the three studies that considered this outcome. CONCLUSIONS: Full recovery from untreated CFS is rare. The prognosis for an improvement in symptoms is less gloomy. This review looks at the course of CF/CFS without systematic intervention. However, there is increasing evidence for the effectiveness of cognitive behavioural and graded exercise therapies. Medical retirement should be postponed until a trial of such treatment has been given.     

The specificity of the CDC-1994 criteria for chronic fatigue syndrome: comparison of health status in three groups of patients who fulfill the criteria

PURPOSE: The Centers for Disease Control (CDC)-1994 definition of chronic fatigue syndrome (CFS) is very broad, and there have been suggestions that it lacks specificity. To test this, we have compared three groups of patients, all of whom fulfill the criteria but self-report different etiologies. METHODS: Patients with self-reported symptoms which developed sporadically (sCFS, n=48); after Gulf War service (GW, n=24); and following exposure to organophosphate insecticides (OP, n=25) underwent a clinical examination, completed the MOS SF-36 quality of life and Hospital Anxiety and Depression scales, and were assessed for major and minor criteria for CDC-1994 CFS. RESULTS: Significant differences in simple clinical measures and outcome measures were observed between groups. The GW group had significantly more severe physical symptoms-fatigue, muscle and multi-joint pain-than OP or sCFS, and the sCFS group was significantly less impaired than the other two groups in terms of role emotional and mental health. In all three groups, a majority of patients exhibited muscle weakness in the lower limbs, and significant numbers of patients had absent or abnormal reflexes. CONCLUSIONS: Differences in simple, easily performed clinical outcome measurements can be observed between groups of patients, all of whom fulfill the CDC-1994 criteria for CFS. It is likely that their response to treatment may also vary. The specificity of the CFS case definition should be improved to define more homogeneous groups of patients for the purposes of treatment and research.     

Identification of ambiguities in the 1994 chronic fatigue syndrome research case definition and recommendations for resolution

Background  

A recent article by Reeves et al. on the identification and resolution of ambiguities in the 1994 chronic fatigue syndrome (CFS) research case definition recommended the Checklist Individual Strength, the Chalder Fatigue Scale, and the Krupp Fatigue Severity Scale for evaluating fatigue in CFS studies. To be able to discriminate between various levels of severe fatigue, extreme scoring on the individual items of these questionnaires must not occur too often.     

Is chronic fatigue syndrome synonymous with effort syndrome?

Chronic fatigue syndrome (CFS), including myalgic encephalomyelitis (ME) and postviral syndrome (PVS), is a term used today to describe a condition of incapacity for making and sustaining effort, associated with a wide range of symptoms. None of the reviews of CFS has provided a proper consideration of the effort syndrome caused by chronic habitual hyperventilation. In 100 consecutive patients, whose CFS had been attributed to ME or PVS, the time course of their illness and the respiratory psychophysiological studies were characteristic of chronic habitual hyperventilation in 93. It is suggested that the labels 'CFS', 'ME' or 'PVS' should be withheld until chronic habitual hyperventilation - for which conventional rehabilitation is available - has been definitively excluded.     

Interventions for the treatment, management and rehabilitation of patients with chronic fatigue syndrome/myalgic encephalomyelitis: an updated systematic review

OBJECTIVES: To determine whether any particular intervention or combination of interventions is effective in the treatment, management and rehabilitation of adults and children with a diagnosis of chronic fatigue syndrome / myalgic encephalomyelitis (CFS/ME). DESIGN: Substantive update of a systematic review published in 2002. Randomized (RCTs) and non-randomized controlled trials of any intervention or combination of interventions were eligible for inclusion. Study participants could be adults or children with a diagnosis of CFS/ME based on any criteria. We searched eleven electronic databases, reference lists of articles and reviews, and textbooks on CFS/ME. Additional references were sought by contact with experts. RESULTS: Seventy studies met the inclusion criteria. Studies on behavioural, immunological, pharmacological and complementary therapies, nutritional supplements and miscellaneous other interventions were identified. Graded exercise therapy and cognitive behaviour therapy appeared to reduce symptoms and improve function based on evidence from RCTs. For most other interventions, evidence of effectiveness was inconclusive and some interventions were associated with significant adverse effects. CONCLUSIONS: Over the last five years, there has been a marked increase in the size and quality of the evidence base on interventions for CFS/ME. Some behavioural interventions have shown promising results in reducing the symptoms of CFS/ME and improving physical functioning. There is a need for research to define the characteristics of patients who would benefit from specific interventions and to develop clinically relevant objective outcome measures.     

‘Betwixt and between’; liminality in recovery stories from people with myalgic encephalomyelitis (ME) or chronic fatigue syndrome (CFS)

This paper explores experiences of 16 people claiming to have recovered from Myalgic Encephalomyelitis (ME) or Chronic Fatigue Syndrome (CFS) using the concept of liminality. Liminality describes the status of those falling between socially recognised and medically sanctioned categories, and illuminates both the experience of illness and the process of recovery from ME/CFS. The liminality experienced during illness was akin to that described by Turner with a degree of communitas among sufferers. As recovery progressed, participants stressed the percentage to which they had improved, and compared themselves with peers and themselves prior to the illness. Recovery did not mean transition into a post‐liminal phase, but involved a new liminality, characterised by straddling boundaries between illness and wellness. Participants continued strategies such as rest, pacing and meditation. This second liminal state included difficulty in communicating the experience convincingly, and estrangement from the ME/CFS community. Thus, recoverees moved from the liminality of illness to a second, and less legible state of sustained liminality in recovery, described as having one foot in the ill world, one foot in the well world. This suggests that more needs to be understood about the recovery experience to assist those making the transition toward wellness.     

Chronic fatigue and chronic fatigue syndrome: A co-twin control study of functional status

Chronic fatigue syndrome (CFS) and the symptom of chronic fatigue may be accompanied by substantial functional disability. A volunteer sample of twins discordant for fatigue was identified from throughout the US. Fatigued twins were classified using three increasingly stringent definitions: (1) 6 months of fatigue (119 pairs); (2) CFS-like illness based on self-report of the Centers for Disease Control and Prevention CFS research definition criteria (74 pairs); and (3) CFS assessed by clinical examination (22 pairs). Twins with chronic fatigue were compared with their unaffected co-twins on the eight standard scales and two physical and mental component summary scales from the medical outcomes study short-form health survey (SF-36). Substantial impairment was observed for fatigued twins across all levels of fatigue, while scores in the healthy twins were similar to US population values. Mean scores among fatigued twins on the physical and mental component summary scales were below 97 and 77%, respectively, of the US population scores. Diminished functional status was found across increasingly stringent classifications of fatigue and was associated with a dramatic decrement in physical functioning. The symptom of fatigue has a pronounced impact on functional status, especially in the domain of physical functioning.     

Epidemiology of chronic fatigue syndrome

BACKGROUND: Chronic fatigue syndrome (CFS) is a controversial disorder with different case definitions, aetiological models and proposed treatments. An epidemiological approach is likely to bring some clarity to the field. AIM: The aim of this article is to review the literature on the epidemiology of fatigue, chronic fatigue and CFS. METHOD: A literature search was conducted using the databases Medline and Pubmed as well as the reference lists of recent reviews to identify the relevant studies. The aim was not to do a systematic review but to review the key studies in the area to highlight the methodological issues. RESULTS: The review is organized according to the following areas: the prevalence of fatigue and chronic fatigue, the prevalence and incidence of CFS, epidemiological associations such as gender, social class and psychiatric co-morbidity and CFS in special groups such as those recovering from a viral infection, specific occupational groups and Gulf War veterans. CONCLUSION: While fatigue as a symptom is very common, CFS is relatively rare. Many of the epidemiological associations seen in specialist clinics are not found in community samples. It is unlikely that one specific causal factor can explain CFS. Future studies should go beyond estimating the prevalence to testing more complex aetiological models.     

Severity Scales for Use in Primary Health Care to Assess Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a physical and cognitive disabling illness, characterized by severe fatigue and a range of physiological symptoms, that primarily affects women. The immense variation in clinical presentation suggests differences in severity based on symptomology and physical and cognitive functional capacities. In this article, we examine a number of severity scales used in assessing severity of patients with CFS/ME and the clinical aspects of CFS/ME severity subgroups. The use of severity scales may be important in CFS/ME because it permits the establishment of subgroups that may improve accuracy in both clinical and research settings.     

The utility of patient-reported outcome measures among patients with myalgic encephalomyelitis/chronic fatigue syndrome

Purpose

Debilitating fatigue is a core symptom of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS); however, the utility of patient-reported symptom outcome measures of fatigue for ME/CFS patients is problematic due to ceiling effects and issues with reliability and validity. We sought to evaluate the performance of three patient-reported symptom measures in a sample of ME/CFS patients and matched controls.

Methods

Two hundred and forty ME/CFS patients and 88 age, sex, race, and zip code matched controls participated in the study. Participants completed the Multidimensional Fatigue Inventory-20, DePaul Symptom Questionnaire, and RAND SF-36.

Results

The general and physical fatigue subscales on Multidimensional Fatigue Inventory-20, as well as the role of physical health on the RAND SF-36, demonstrated questionable or unacceptable internal consistency and problematic ceiling effects. The DePaul Symptom Questionnaire demonstrated excellent internal reliability, and less than 5 % of participants were at the ceiling on each subscale. The post-exertional malaise subscale on the DePaul Symptom Questionnaire demonstrated excellent clinical utility as it was able to differentiate between ME/CFS patients and controls (OR 1.23, p < .001) and predicted ceiling effects on other patient-reported outcome subscales. A score of 20 on the post-exertional malaise subscale of the DePaul Symptom Questionnaire optimally differentiated between patients and controls.

Conclusions

Significant ceiling effects and concerns with reliability and validity were observed among Multidimensional Fatigue Inventory-20 and RAND SF-36 subscales for ME/CFS patients. The DePaul Symptom Questionnaire addresses a number of concerns typically identified when using patient-reported outcome measures with ME/CFS patients; however, an improved multidimensional patient-reported outcome tool for measuring ME/CFS-related symptoms is warranted.

     

Social support needs for equity in health and social care: a thematic analysis of experiences of people with chronic fatigue syndrome/myalgic encephalomyelitis

Background

Needs-based resource allocation is fundamental to equitable care provision, which can meet the often-complex, fluctuating needs of people with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). This has posed challenges both for those providing and those seeking support providers, in building shared understanding of the condition and of actions to address it. This qualitative study reports on needs for equity in health and social care expressed by adults living with CFS/ME.

Methods

The participants were 35 adults with CFS/ME in England, purposively selected to provide variation in clinical presentations, social backgrounds and illness experiences. Accounts of experienced needs and needs-related encounters with health and social services were obtained through a focus group (n = 6) and semi-structured interviews (n = 35). These were transcribed and needs related topics identified through data-led thematic analysis.

Findings

Participants emphasised needs for personalised, timely and sustained support to alleviate CFS/ME impacts and regain life control, in three thematic areas: (1) Illness symptoms, functional limitations and illness management; (2) practical support and social care; (3) financial support. Access of people with CFS/ME to support from health and social services was seen to be constrained by barriers stemming from social, cultural, organisational and professional norms and practices, further heightened for disadvantaged groups including some ethnic minorities. These reduced opportunities for their illness to be explained or associated functional limitations and social disadvantages to be addressed through social support. Participants sought more understanding of bio-psycho-social aspects of CFS/ME, of felt needs of people with CFS/ME and of human rights and disability rights, for providing person-centred, equitable care.

Conclusions

Changes in attitudes of health practitioners, policy makers and general public and more flexibly organised health and social care provision are needed to address equity issues in support needs expressed by people with CFS/ME, to be underpinned by research-based knowledge and communication, for public and professional education. Policy development should include shared decision-making and coordinated action across organizations working for people with CFS/ME, human rights and disadvantaged groups. Experiences of people with CFS/ME can usefully inform an understanding of equity in their health and social care.