Tag: case definition

What Long COVID investigators can learn from four decades of ME/CFS research

Abstract:

Four decades of research in the field of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) have yielded lessons that may be instructive for those devising criteria to better comprehend Post-Acute Sequelae of SARS CoV-2 Infection (PASC) and Long COVID.

For instance, substantial effort has been devoted to defining classification systems, operationalizing methods, and developing instruments with adequate reliability and validity in the ME/CFS field.

The current article provides guidelines for developing a case definition for Long COVID and discusses the significance of psychometric issues and criterion variance, including how to specify symptoms, develop thresholds, subtypes, and exclusionary conditions. ME/CFS research could enhance our knowledge of Long COVID pathophysiology, early diagnosis, prognosis, and the identification of effective treatments.

Source: Leonard A. Jason, Benjamin H. Natelson, Hector Bonilla, Zaki A. Sherif, Suzanne D. Vernon, Monica Verduzco Gutierrez, Lisa O’Brien, Emily Taylor. What Long COVID investigators can learn from four decades of ME/CFS research. Brain Behavior and Immunity Integrative, Volume 4, 2023, 100022. https://www.sciencedirect.com/science/article/pii/S2949834123000211 (Full text)

The importance of estimating prevalence of ME/CFS in future epidemiological studies of long COVID

Abstract:

The resolution of the COVID-19 pandemic is giving rise to another public health challenge due to the explosion of long COVID (LC) cases. In many cases, LC results in persistent fatigue, post-exertional malaise (PEM), and other debilitating symptoms that resemble the clinical manifestation of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). The similarity of these two diseases suggests that future epidemiological studies of LC could take the opportunity to also estimate the prevalence of ME/CFS at a minimal cost.

With this opportunity in mind, we revisited the most consensual case definitions of ME/CFS for research purposes. We then compared the symptoms assessed at the participants’ enrollment in the UK ME/CFS Biobank with those documented in three systematic reviews encompassing hundreds of LC epidemiological studies. We found that published epidemiological studies of LC did not consistently assess or report the prevalence of PEM, which is a compulsory symptom for ME/CFS diagnosis. However, these studies assessed many neuro-cognitive, immunologic, and autonomic symptoms.

In this scenario, we recommend that the estimation of ME/CFS prevalence in the context of LC epidemiology is easily achievable by deploying tested and validated diagnosis tools used in ME/CFS. The knowledge of ME/CFS prevalence within the LC population is of cardinal importance to optimal allocation of resources and better design of healthcare interventions to manage and treat patients with this devastating disease.

Source: Anna D. Grabowska, Francisco Westermeier, Luís Nacul, Eliana Lacerda, Nuno Sepúlveda. The importance of estimating prevalence of ME/CFS in future epidemiological studies of long COVID. DOI:10.13140/RG.2.2.20997.52967 https://www.researchgate.net/publication/373043778_The_importance_of_estimating_prevalence_of_MECFS_in_future_epidemiological_studies_of_long_COVID (Full text)

Impact of Misdiagnosis in Case-Control Studies of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Misdiagnosis of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) can occur when different case definitions are used by clinicians (relative misdiagnosis) or when failing the genuine diagnosis of another disease (misdiagnosis in a strict sense). This problem translates to a recurrent difficulty in reproducing research findings.

To tackle this problem, we simulated data from case-control studies under misdiagnosis in a strict sense. We then estimated the power to detect a genuine association between a potential causal factor and ME/CFS. A minimum power of 80% was obtained for studies with more than 500 individuals per study group.

When the simulation study was extended to the situation where the potential causal factor could not be determined perfectly (e.g., seropositive/seronegative in serological association studies), the minimum power of 80% could only be achieved in studies with more than 1000 individuals per group.

In conclusion, current ME/CFS studies have suboptimal power under the assumption of misdiagnosis. This power can be improved by increasing the overall sample size using multi-centric studies, reporting the excluded illnesses and their exclusion criteria, or focusing on a homogeneous cohort of ME/CFS patients with a specific pathological mechanism where the chance of misdiagnosis is reduced.

Source: Malato J, Graça L, Sepúlveda N. Impact of Misdiagnosis in Case-Control Studies of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Diagnostics. 2023; 13(3):531. https://doi.org/10.3390/diagnostics13030531 https://www.mdpi.com/2075-4418/13/3/531 (Full text)

The Hindi Version of International Consensus Criteria: A Cross-cultural Adaptation and Validation Study for Myalgic Encephalomyelitis in Post-COVID Patients

Abstract: 

Context: Fatigue is the most prominent feature of long COVID. With the increasing burden of long COVID cases post-acute phase of illness after recurrent waves of the pandemic, understanding its pathophysiology is of paramount importance.

Such fatigue and post-viral illness could be associated with features of neuroimmune exhaustion and thus be a part of a larger syndrome such as myalgic encephalomyelitis (ME).

Identifying the proportion of patients having ME from those experiencing fatigue would bring us one step closer to understanding the pathophysiology. International consensus criteria (ICC) originally published in English (ICC-E) is a valid and reliable tool for identifying cases of ME. However, a validated Hindi version of ICC-E is not available.

Aims: To develop and validate an equivalent version of ICC-E in the native Hindi language (ICC-H) to suit Indian patients and health care workers even at peripheries and to make conducting large scales surveys more feasible.

Subjects and methods: Once permission from the ethics board was granted, guidelines given by MAPI Research Trust were followed and ICC-H was developed from ICC-E, in the following steps: (a) translation to Hindi, (b) back translation, (c) comparison between the translated and back-translated version performed by experts, and (d) pre-pilot test in the intended population. The ICC-H was applied to 53 bilingual individuals knowing both Hindi and English.

Statistical analysis used: The distribution of Hindi and English questionnaires was analyzed using the Chi-square test and Spearman’s correlation coefficient was used for correlation between answers of each question.

Results: The score of individual items and its global score was highly correlated with each other (p<0.001). The scores of individual components and global scores of ICC-H at baseline and original ICC-E after 4 weeks did not differ significantly.

Conclusion: This study shows that the ICC-H is a valid and reliable instrument for the assessment of ME. ICC-H can be used for Hindi speaking population for identifying cases of ME.

Source: Shah M, Kakar A, Gogia A. The Hindi Version of International Consensus Criteria: A Cross-cultural Adaptation and Validation Study for Myalgic Encephalomyelitis in Post-COVID Patients. J Assoc Physicians India 2022;70(10):59–63. https://www.japi.org/x2d4b494/the-hindi-version-of-international-consensus-criteria-a-cross-cultural-adaptation-and-validation-study-for-myalgic-encephalomyelitis-in-post-covid-patients  https://www.researchgate.net/profile/Atul-Gogia/publication/364241915_Postgraduate_Student_2_Vice_Chairman_and_Senior_Consultant_The_Hindi_Version_of_International_Consensus_Criteria_A_Cross-cultural_Adaptation_and_Validation_Study_for_Myalgic_Encephalomyelitis_in_Post-/links/63405e8aff870c55ce0adebf/Postgraduate-Student-2-Vice-Chairman-and-Senior-Consultant-The-Hindi-Version-of-International-Consensus-Criteria-A-Cross-cultural-Adaptation-and-Validation-Study-for-Myalgic-Encephalomyelitis-in-Post.pdf (Full text available as PDF file)

Separating patients with SEID from those with CFS in the French ME/CFS Association, with some thoughts on nomenclature

Abstract:

In 2015, the American Institute of Medicine, now called the National Academy of Medicine, (IOM/NAM) proposed new diagnostic criteria for both Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and a new label: Systemic Exertion Intolerance Disease (SEID). This study aimed to evaluate the SEID criteria among members of the French Association of ME/CFS (ASFC) and their opinion about this new name. We sent an anonymous questionnaire to 494 ASFC members, using French-translated questions derived from the IOM/NAM tool kit. Among the 178/231 responding subjects who reported ME/CFS diagnosis, 150 (84%) met the criteria of SEID. For each set of questions, we identified some of them that significantly distinguished SEID from non-SEID patients concerning unrefreshing sleep, cognitive disorders, and orthostatic intolerance items.
Forty-six percent of the respondents considered the “SEID” terminology as more appropriate than “CFS”, 39% considered it inappropriate, and 15% had no opinion. Some questions better identified the SEID criteria. The IOM/NAM SEID criteria captured a large part of ASFC members suffering from ME/CFS. However, this new SEID label was not well accepted by the subjects, nor were the other denominations, suggesting that a better term should be found. Pending development of specific markers, further work with patient communities is needed to find a more suitable label.
Source: Campagne J, Fornasieri I, Andreani B, Eginard M, de Korwin J-D. Separating Patients with SEID from Those with CFS in the French ME/CFS Association, with Some Thoughts on Nomenclature. Diagnostics. 2022; 12(5):1095. https://doi.org/10.3390/diagnostics12051095. https://www.mdpi.com/2075-4418/12/5/1095 (Full text available as PDF file)

Evaluating case diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): toward an empirical case definition

Abstract:

Purpose: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is an illness characterized by a variety of symptoms including post-exertional malaise, unrefreshing sleep, and cognitive impairment. A variety of case definitions (e.g., the Canadian Consensus Criteria (CCC), the Myalgic Encephalomyelitis International Consensus Criteria (ME-ICC), and the Institute of Medicine (IOM) criteria) have been used to diagnose patients. However, these case definitions are consensus-based rather than empirical.

Materials and methods: The aim of the current study was to evaluate the validity of the aforementioned case definitions by factor analyzing a large, international sample (N = 2308) of ME/CFS symptom data. We performed primary and secondary exploratory factor analyses on the DePaul Symptom Questionnaire’s 54-item symptom inventory. These results were compared to the CCC, the ME-ICC, and the IOM criteria.

Results: We identified seven symptom domains, including post-exertional malaise, cognitive dysfunction, and sleep dysfunction. Contrary to many existing case criteria, our analyses did not identify pain as an independent factor.

Conclusions: Although our results implicate a factor solution that best supports the CCC, revisions to the criteria are recommended. Implications for rehabilitation: ME/CFS is a chronic illness with no consensus regarding case diagnostic criteria, which creates difficulty for patients seeking assistance and disability benefits. The current study compared three commonly used case definitions for ME/CFS by factor analyzing symptomological data from an international sample of patients. Our results suggest three primary and four secondary symptom domains which differed from all three case definitions. These findings could help reduce barriers to care for those disabled with ME/CFS by guiding the development of an empirically-based case definition.

Source: Conroy KE, Islam MF, Jason LA. Evaluating case diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): toward an empirical case definition. Disabil Rehabil. 2022 Mar 2:1-8. doi: 10.1080/09638288.2022.2043462. Epub ahead of print. PMID: 35236205. https://pubmed.ncbi.nlm.nih.gov/35236205/

Missteps in Creating a Long Haul COVID Case Definition

Excerpt:

Millions of individuals who have not recovered from the COVID virus are now dealing with a host of symptoms that are challenging our health care system. Many are experiencing significant problems in being recognized by health care workers as a real disorder, as for many of them, there are no biological markers of persistent illness. Just as with ME/CFS, we need to be sure that long haul COVID patients are not victimized first by the pandemic and then by the health care skepticism of their significant symptoms. We have the conceptual and theoretical grounding to develop clinical and research case definitions for those with persisting COVID symptoms. Patients must be instrumentally involved in all such efforts as failure to do so will only further delegitimize their condition.

Read the rest of this article HERE.

Source: Leonard Jason, Ph.D. and Vernita Perkins, PhD. Missteps in Creating a Long Haul COVID Case Definition. Psychology Today. Posted November 22, 2021