Tag: letter

Response to treatment in the Multiple Symptoms Study 3 trial

Letter:
Chistopher Burton and colleagues conducted an unblinded trial of a consultative intervention for 354 people with persistent physical symptoms but no identifiable “organic” cause. Patient Health Questionnaire-15 (PHQ-15) score, which is a brief, subjective, self-administered screen of severity of somatic complaints, was the primary outcome. This kind of trial design can be expected to produce modest positive outcomes, via expectation bias alone. No real-life, objective assessment of functioning was conducted.
The intervention involved up to four sessions with a general practitioner, offering patients “rational explanations” for their symptoms in the absence of known, falsifiable causes and helping patients to develop strategies for managing symptoms. Although the “rational explanations” are not described, they presumably did not include “organic” diseases or conditions.
Scores on the PHQ-15 range from 0 to 30. Recruited patients had scores from 10 to 20, indicating moderate severity. At the end of the study, the adjusted between-group difference of –1·82 did not reach the minimal clinically important difference of 2·3. The change is well within what would be expected from bias alone. The results therefore confirmed that the intervention was of limited, if any, practical benefit. However, the paper presents the findings as though they had shown the opposite.
Instead of the “rational explanations” promoted by the investigators, more straightforward and honest explanations—for example, we do not know what is causing symptoms—could easily have produced similar results. Patients desire resolution of symptoms and recovery of functions. The trial did not achieve this result. Post-intervention, participants continue to have an impaired quality of life and poor experiences of health care.
DT holds an academic position at the Center for Global Public Health at UC Berkeley, which is largely supported by crowdfunded donations directly to the university, many of them from patients with myalgic encephalomyelitis or chronic fatigue syndrome and related conditions that fall under the heading of persistent physical symptoms. JSC declares no competing interests.
Source: Joan S Crawford and David Tuller. Response to treatment in the Multiple Symptoms Study 3 trial.  The Lancet, Volume 405, Issue 10485, 1145 – 1146  https://link.springer.com/article/10.1007/s00421-025-05759-5 (Full text)

Letter: Time to correct the record on the global burden of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Dear Editor,

We have read Lim et al.’s study [1] with great interest. Studies of this illness are scarce, so their article is important in establishing the global prevalence systematically. In fact, it has been cited over 200 times and has had a significant influence on global reporting of the burden of ME/CFS. Unfortunately, the core figure that is most frequently drawn from the article is a significant underestimate of the prevalence of ME/CFS, and has led to the spread of misinformation about the burden of this disease.

A global ME/CFS population of 17 to 24 million people is reported in articles such as those published in BMC Medicine [2] and Science [3], all referencing Lim et al. The same range of numbers is also easy to find in patient advocacy websites and news reports, such as those of the American Myalgic Encephalomyelitis and Chronic Fatigue Syndrome Society [4] and CNN [5], all updated after Lim et al.’s article was published. However, this figure is drawn from the Background section of Lim et al.’s article, where they state, “In worldwide statistics, approximately 1% of the population, 17 to 24 million people, suffer from this condition [14], which is likely to be as common as rheumatoid arthritis” [1]. The cited reference (reference [14]) is an article about the global burden of multiple sclerosis, and is not relevant to the global ME/CFS population.

The actual headline result of the study by Lim et al. was an estimated prevalence of 0.89% using the CDC-1994 definition, as indicated in the Discussion and Conclusions sections of their article [1]. If we correctly apply this to the global population of 8 billion, the true prevalence of ME/CFS would be 71.2 million (71,200,000). However, new research using more up-to-date datasets and methods is essential to gain a full understanding of the burden of this disease.

Due to this unfortunate misreading and misattribution by others of an erroneous reference in the Background section of Lim et al.’s article, there is widespread underestimation of the true burden of ME/CFS. Such underestimation may exacerbate the isolation, stigmatization, and suffering of people living with this poorly-understood and under-recognized illness. More effort is needed to correct this underestimation globally, develop treatment methods and welfare support, and relieve the burden of ME/CFS. Correct reporting of the true prevalence of this disease is an important first step to addressing the ongoing neglect that its sufferers experience, and this can begin with the correct reporting of Lim et al.’s research.

Source: Vardaman M, Gilmour S. Letter: Time to correct the record on the global burden of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). J Transl Med. 2025 Mar 14;23(1):331. doi: 10.1186/s12967-025-06281-0. PMID: 40087760. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-025-06281-0 (Full text)

Recognizing the role of fibromyalgia in post-exertional malaise

Letter:

The recent opinion by Charlton et al. published in Trends in Endocrinology & Metabolism [] provides a thought-provoking discussion of the overlap between long coronavirus disease (long-COVID) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), emphasizing the centrality of post-exertional malaise (PEM) as a shared mechanism.

Here, we suggest that fibromyalgia should be included in the discussion, given the established role of PEM in this condition []. In addition, fibromyalgia not only shares symptomatic and mechanistic overlaps with ME/CFS, but also offers a complementary perspective on the pathophysiology of PEM. Considering that PEM is a key symptom in both fibromyalgia and long COVID, exploring skeletal muscle function in fibromyalgia could provide complementary insights into the muscle-specific alterations that contribute to this debilitating phenomenon.

Source: Giollo A, Salvato M, Doria A. Recognizing the role of fibromyalgia in post-exertional malaise. Trends Endocrinol Metab. 2025 Mar 11:S1043-2760(25)00045-1. doi: 10.1016/j.tem.2025.02.005. Epub ahead of print. PMID: 40074568. https://www.cell.com/trends/endocrinology-metabolism/abstract/S1043-2760(25)00045-1

On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection

Introduction:

There is an increasing body of evidence connecting the post-acute SARS-CoV-2 condition (PASC, commonly known as long COVID) to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a debilitating disease of unknown cause characterized by persistent and unexplained fatigue, post-exertional malaise (PEM), among other symptoms. This connection implies that, in the clinic, some PASC cases comply with the official case definitions of ME/CFS. As such, there is a necessity to quantify the burden of ME/CFS among the PASC population in order to delineate effective healthcare interventions for the benefit of these patients who are often neglected or, in some extreme cases, stigmatized by medical staff and society.
To answer this urgent research question, Dehlia and Guthridge performed a systematic review and meta-analysis of recent data on PASC adults and reported an ME/CFS prevalence estimate of 51% (95% CI, 42%-60%); this systematic review and meta-analysis will be referred to as PASC-ME/CFS study. In the present Letter to Editor, we aimed to discuss the reliability of this estimate using the research protocol from the European Network on ME/CFS (EUROMENE) for systematic reviews and meta-analysis on the epidemiology burden of ME/CFS in Europe.

Source: Sepúlveda N, Westermeier F. On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection. J Infect. 2024 Nov 16:106353. doi: 10.1016/j.jinf.2024.106353. Epub ahead of print. PMID: 39557089. Sepúlveda N, Westermeier F. On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection. J Infect. 2024 Nov 16:106353. doi: 10.1016/j.jinf.2024.106353. Epub ahead of print. PMID: 39557089. https://www.journalofinfection.com/article/S0163-4453(24)00288-3/fulltext (Full text)

Correspondence: Inaccurate reference leads to tripling of reported FND prevalence

Highlights:

  • Perez et al asserted that FND is the “2nd most common” diagnosis in outpatient neurology.
  • Stone et al (2010), cited by Perez et al, does not support the “2nd most common” claim.
  • In Stone et al, a broad “functional/psychological” category was the second most common
  • •

    FND is not synonymous with the “functional/psychological” category in Stone et al.

To the editor:

An article in NeuroImage: Clinical, “Neuroimaging in functional neurological disorder: state of the field and research agenda” (Perez et al., 2021), cited a prominent paper (Stone et al., 2010) as evidence for the assertion that functional neurological disorder (FND) is the “2nd most common outpatient neurologic diagnosis.” Although studies have yielded varying FND prevalence rates, the claim that it is the second-most common diagnosis at outpatient neurology clinics represents an erroneous interpretation of the findings of the referenced 2010 paper.

FND is the current name for what was formerly called conversion disorder, the diagnosis previously given to patients believed to have psychogenic motor and gait dysfunctions, sensory deficits, and non-epileptic seizures. According to the 2013 edition of the Diagnostic and Statistical Manual of Mental Disorders and as noted in Perez et al, FND is not a diagnosis of exclusion but requires the presence of specific “rule-in” clinical signs believed to be incompatible with known neurological disease. Some of these clinical signs have long been used by neurologists and other clinicians to help them identify cases of conversion disorder.

Stone et al.,’s (2010) paper was one of several arising from the Scottish Neurological Symptoms Study (SNSS). The study reviewed records from multiple outpatient neurology clinics and reported that 209 of 3781 attendees, or less than 6 %, received diagnoses compatible with conversion disorder–in other words, what would now be called FND. In terms of ranking, this group of patients—labeled in the SNSS as having “functional” symptoms or diagnoses–was far down the list. The study found higher rates of many other conditions, including headache (19 %), epilepsy (14 %), peripheral nerve disorders (11 %), miscellaneous neurological disorders (10 %), multiple sclerosis/demyelination (7 %), spinal disorders (6 %) and Parkinson’s disease/movement disorders (6 %).

Earlier this year, a paper in the European Journal of Neurology (Mason et al., 2023) cited a different SNSS paper (Stone et al., 2009) to support the assertion that FND prevalence at outpatient neurology clinics was 5.4 %—far lower than the percentage needed to be the “2nd most common” diagnosis. Moreover, the authors of another paper (Foley et al., 2022) have recently issued a correction for the same misstatement of FND prevalence from the SNSS findings as the one identified in Perez et al.

The assertion that the SNSS found FND to be the “2nd most common” diagnosis at outpatient neurology clinics is based on a parallel and commonly repeated claim that the study found the prevalence in these settings to be 16 % (e.g. Ludwig et al., 2018). That rate is almost three times the 5.4 % prevalence recently highlighted in Mason et al. The extra patients included in this greatly expanded FND category were another 10 % collectively identified in the SNSS as having “psychological” symptoms or diagnoses. These “psychological” patients fell into a range of clinical sub-categories, among them hyperventilation, anxiety and depression, atypical facial/temporomandibular joint pain, post-head injury symptoms, fibromyalgia, repetitive strain injury, and alcohol excess. The SNSS paper cited in Perez et al reported that a combined grouping of the patients with “functional and psychological” symptoms or diagnoses had a prevalence of 16 % but did not provide any evidence that the 10 % included under the “psychological” label met, or could have met, the explicit FND requirement for rule-in clinical signs.

FND is not synonymous with the broader “functional and psychological” category in the SNSS and should not be presented as if it were. The post-hoc reinterpretation of previously reported data in a way that conflates FND with other complex conditions—almost tripling its apparent prevalence in the process–is an example of the phenomenon known as diagnostic creep. In any event, the SNSS results are a matter of record. Whatever future studies might determine about FND rates, the published findings cited by Perez et al and addressed in this letter do not support either the claim that it is the “2nd most common” diagnosis in outpatient neurology clinics or the related claim that its prevalence at these venues is 16 %.

Sincerely–

David Tuller (corresponding author)

Center for Global Public Health

School of Public Health

University of California, Berkeley

Berkeley, CA, USA

David Davies-Payne

Department of Radiology

Starship Children’s Hospital

Auckland, New Zealand

Jonathan Edwards

Department of Medicine

University College London

London, England, UK

Keith Geraghty

Centre for Primary Care and Health Services Research

Faculty of Biology, Medicine and Health

University of Manchester

Manchester, England, UK

Calliope Hollingue

Center for Autism and Related Disorders/Kennedy Krieger Institute

Department of Mental Health/Johns Hopkins Bloomberg School of Public Health

Johns Hopkins University

Baltimore, MD, USA

Mady Hornig

Department of Epidemiology

Columbia University Mailman School of Public Health

New York, NY, USA

Brian Hughes

School of Psychology

University of Galway

Galway, Ireland

Asad Khan

North West Lung Centre

Manchester University Hospitals

Manchester, England, UK

David Putrino

Department of Rehabilitation Medicine

Icahn School of Medicine at Mt Sinai

New York, NY, USA

John Swartzberg

Division of Infectious Diseases and Vaccinology

School of Public Health

University of California, Berkeley

Berkeley, CA, USA

Source: Correspondence: Inaccurate reference leads to tripling of reported FND prevalence. Neuroimage Clin. 2024 Feb 7;41:103537. doi: 10.1016/j.nicl.2023.103537. Epub ahead of print. PMID: 38330816. https://www.sciencedirect.com/science/article/pii/S2213158223002280 (Full text)

Re: What happens inside a long covid clinic?

Dear Editor

As a patient with severe long covid and myalgic encephalomyelitis (M.E.), I was pleased to see the article ‘What happens in a long covid clinic?’ [1] raising awareness of the scale and impact of long covid and the importance of long covid clinics. According to a recent estimate by Altmann et al, 1 in 10 people who contract COVID-19 will be affected by long covid, whilst the oncoming impact of long covid on health systems, populations and economies will be “so large as to be unfathomable”.[2]

Around 2-14% of patients with long covid develop orthostatic tachycardia six to eight months after COVID infection and as many as 60% show some symptoms of POTS. [3] Yet there remain no agreed guidelines for POTS in long covid, making the early diagnosis and management of the condition in primary care challenging. NICE guidance on long covid only mentions POTS in passing with no information on management.[4] The approach outlined by Espinosa-Gonzalez and colleagues to diagnose and manage POTS in primary care could greatly improve function and health for people with POTS.[5]

While I commend the excellent NHS services highlighted in the feature [1], as a patient with severe long covid I would question how prevalent this integrated medically-led care model is across the country despite it being in the ‘The NHS plan for improving long covid services’.[6] Many patients I speak to in long covid support groups report long waits, only to then be offered basic wellbeing classes or rehabilitation without any active treatment for symptoms.

Access to clinics for the most severely affected is variable with not all services offering remote consultations or home visits. It is imperative that long covid clinics are medically led, inter-disciplinary and able to prescribe medications. Additionally, we need the same standard of care for patients with ME/CFS, who are still waiting for NICE guidance from 2021[7] to be implemented. A recent survey noted there remain significant gaps in provision for patients with ME/CFS.[8]

Previously young fit and healthy patients with severe long covid and ME are being left bed-bound without adequate diagnosis, support, care or treatment as there is no specialty or service that is set up to provide this. I went from climbing mountains and working on-call to unable to stand or feed myself in the space of 8 weeks with long covid – I am still severely affected a year later. Given the multi-system complexity of long covid and ME/CFS it is time for an interdisciplinary patient-centred service for post-viral illnesses that recognises the biological nature of the disease and the unique challenges patients with severe long covid and ME have with safely accessing services given their limited energy available, severe cognitive effects, physical immobility and range of complications across bodily systems.

The Department of Health and Social Care are currently seeking views on the interim delivery plan for ME/CFS care in an online consultation [9], which is relevant to both patient groups and professionals and could lay the groundwork for more comprehensive care of post-viral illnesses in the UK.

Yours sincerely,

Dr Alexis Gilbert BSc MBBS MPH FFPH

Source: MJ 2023;382:p1791 https://www.bmj.com/content/382/bmj.p1791/rr (Full text)

Mast cell activation may contribute to adverse health transitions in COVID-19 patients with frailty

Abstract:

A prominent aspect of the post-coronavirus disease-2019 (post-COVID-19) era is long-COVID. Therefore, precise patient classification and exploration of the corresponding factors affecting long-COVID are crucial for tailored treatment strategies. Frailty is a common age-related clinical syndrome characterized by deteriorated physiological functions of multiple organ systems, which increases susceptibility to stressors.

Herein, we performed an inclusion and exclusion analysis (definite COVID-19 infection diagnosis, clear underlying disease information, ≥60 years old, and repeated sampling of clinical cases) of 10,613 blood samples and identified frailty cases for further investigation. RNA-Seq data were used for differential gene expression and functional and pathway analyses.

The results revealed that patients with frailty were more prone to poor health conversions and more sequelae, and the blood transcriptome had obvious disturbances in pathways associated with immune regulation, metabolism, and stress response. These adverse health transitions were significantly associated with mast cell activation. Additionally, NCAPG, MCM10, and CDC25C were identified as hub genes in the peripheral blood differential gene cluster, which could be used as diagnostic markers of poor health conversion.

Our results indicate that healthcare measures should be prioritized to mitigate adverse health outcomes in this vulnerable patient group, COVID-19 patients with frailty, in post-COVID era.

Source: Xiangqi Li, Chaobao Zhang & Zhijun Bao (2023) Mast cell activation may contribute to adverse health transitions in COVID-19 patients with frailty, Emerging Microbes & Infections, 12:2, DOI: 10.1080/22221751.2023.2251589 https://www.tandfonline.com/doi/pdf/10.1080/22221751.2023.2251589 (Full text)

Long COVID, linking etiopathogenic theories

Abstract:

In this letter we discuss the various theories involved in the pathogenesis of Long COVID and how they are closely interrelated, conditioning the full range of symptoms and signs presented by patients affected by this condition, as well as calling for the recognition of the disease by the health authorities that must begin to streamline their health processes to limit the burden of this disease, which tends to be chronic and degenerative.

Source: Luis del Carpio-Orantes, Andrés Aguilar-Silva. Long COVID, linking etiopathogenic theories. Qeios, CC-BY 4.0. https://www.qeios.com/read/A7TYBN (Full text)

Prevalence of Post–COVID-19 Conditions Depends on the Method of Assessment

To the Editor—In their systematic review and meta-analysis on the global prevalence of long coronavirus disease 2019 (COVID-19), Chen et al report that a significant share of patients with COVID-19 suffer from sequelae of acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection [1]. The authors performed a database search in PubMed, Embase, and iSearch and included 50 studies comprising hospitalized and nonhospitalized patients from the Americas, Europe, and Asia, of which 41 studies were meta-analyzed. The estimated pooled prevalence of a post–COVID-19 condition was 0.43 (95% confidence interval, .39–.46) [1].

Concerning a post–COVID-19 condition, or long COVID, and their global burden of disease, we think it is important to bear in mind that many studies (including our own [2], which was in the meta-analysis) assess long COVID symptoms via self-report/questionnaires. Self-reported outcomes do not necessarily match clinical reports that are based on physical and/or technical examinations. Thus, there is a difference between functional impairment based on objective medical findings and self-estimation, giving rise to potential detection bias, as the authors briefly mention in the supplement. Moreover, possible bias through elevated media attention, resulting in potentially altered response behavior, must be considered.

Making causal links between nonspecific symptoms, such as dizziness, headache, or fatigue, to SARS-CoV-2 or acute COVID-19 remains challenging [3]. Furthermore, precise pathophysiological mechanisms underlying specific long COVID symptoms have not been fully elucidated [4, 5]. Fatigue, for example, is associated with several chronic conditions and its prevalence in the population is estimated to be in the same range as found in SARS-CoV-2 cases in the present meta-analysis [6]. With regard to the World Health Organization definition, a post–COVID-19 condition may represent a diagnosis per exclusion in many cases [7]. Nonetheless, even if the prevalence of long COVID was overestimated in the underlying studies, COVID-19 sequelae pose a considerable burden on health, social insurance systems, and economies worldwide given the high attack rate of SARS-CoV-2 [8].

Source: Lampl BMJ, Leitzmann MF, Salzberger B. Prevalence of Post-COVID-19 Conditions Depends on the Method of Assessment. J Infect Dis. 2023 Jan 11;227(2):306. doi: 10.1093/infdis/jiac467. PMID: 36546758. https://academic.oup.com/jid/article/227/2/306/6853665 (Full text)

Long-haul COVID: heed the lessons from other infection-triggered illnesses

According to the Johns Hopkins Coronavirus Resource Center, more than 115 million people worldwide have been infected with SARS-CoV-2 during the COVID-19 pandemic, with extensive implications for morbidity and mortality. Description of long-term effects of COVID-19 are apparing in the medical literature; the first large cohort study with 6-months’ follow-up has been published, and more data are sure to follow. A small number of studies point not only to persistent imaging and testing abnormalities across several organ systems in the postacute period, but to a high frequency of patient-reported symptoms such as fatigue, insomnia, anxiety and depression, autonomic disturbances, cognitive difficulties, pain, and others. The presence of patient support groups, and the rapid expansion of clinics to manage or treat these symptoms, validate further their existence and impact.
Although the frequency, severity, and potentially the etiology of persistent symptoms can vary, sequelae after COVID-19 appears poised to join the range of other postinfectious syndromes described in the field of infectious diseases.

These often share a common symptom phenotype, which might also meet case definitions for myalgic encephalomyelitis/chronic fatigue syndrome, fibromyalgia, or post-treatment Lyme disease. We hope that researchers and clinicians will draw on these other conditions as they continue to advance scientific understanding of so-called long-haul or persistent COVID-19. We would also argue that there are important lessons to learn and pitfalls to avoid; our specific area of clinical care and research (post-treatment Lyme disease) has remained a fiercely contentious condition for more than 30 years.

Read the rest of this article HERE.
Source: John N Aucott, Alison W Rebman. Long-haul COVID: heed the lessons from other infection-triggered illnesses. The Lancet, CORRESPONDENCE| VOLUME 397, ISSUE 10278, P967-968, MARCH 13, 2021 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00446-3/fulltext (Full text)