Tag: 2025

Rate of 4.5% Post-COVID ME/CFS Onset Cited in Recent RECOVER Study is Based on Biased Cohort

Letter:

The recent paper by Vernon, et al.1 predicts that 4.5% of adult COVID sufferers in the United States experience subsequent onset of Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS). While the degree of ME/CFS onset is indeed significant, the figure of 4.5% cannot be justified from the provided data.

Vernon, et al. compute a male onset rate of 3.41% (107/3134, see Table 1 of paper) and a female onset rate of 4.91% (422/8600). They then take a weighted average based on the gender breakdown of their cohort, which is 27.7% male and 72.3% female, to arrive at 4.5% overall.

The problem here is that their cohort, which is nearly three-quarters female, is not representative of the adult gender prevalence of COVID in the United States. One can estimate the gender breakdown using the CDC Household Pulse Survey,2 which shows 61.6% of US adults having gotten COVID, 58.6% of males and 64.4% of females. These numbers are consistent with an assumed gender breakdown of the adult population of 48.3% male and 51.7% female, from which can be deduced an adult COVID breakdown of 46% male and 54% female, leading to an ME/CFS onset rate of 4.22%. While significant, this is less than the 4.5% published conclusion.

Source: Mirin AA. Rate of 4.5% Post-COVID ME/CFS Onset Cited in Recent RECOVER Study is Based on Biased Cohort. J Gen Intern Med. 2025 Jul 22. doi: 10.1007/s11606-025-09711-3. Epub ahead of print. PMID: 40696227.  https://link.springer.com/article/10.1007/s11606-025-09711-3 (Full text)

Intelligent Eye Tracker Integrated with Cylindrical Capacitive Sensors for Chronic Fatigue Assessment

Abstract:

Fatigue negatively impacts health, safety, and productivity, yet current monitoring methods are often subjective, labor-intensive, and inaccurate. To address these challenges, this study presents a capacitive sensor-based eye tracker leveraging cylindrical carbon nanotube-paper composite (CCPC) sensors for chronic fatigue (CF) assessment.

Fabricated by novel wet-fracture and paper-rolling methods, CCPC sensors demonstrate superior proximity sensitivity with a small form factor. These one-dimensional sensors are seamlessly integrated into an eyeglass frame for noncontact monitoring of blink rates and eye closures. A 15-minute testing protocol, combining cognitive tasks and noise exposure, is designed to induce acute fatigue and identify CF. By analyzing changes in the digital markers against established fatigue indicators, CF is assessed with the aid of machine learning models for the evaluation of accuracy, sensitivity, and specificity.

This real-time, wearable monitoring platform provides an objective, effortless, and noncontact approach to fatigue assessment. With further testing and optimization, it holds the potential for user-friendly evaluation of acute fatigue or fatigue-associated diseases, such as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

Source: Li T, Park SH, Lee C, Kim S, Kwon Y, Kim H, Chung JH. Intelligent Eye Tracker Integrated with Cylindrical Capacitive Sensors for Chronic Fatigue Assessment. Adv Sens Res. 2025 Jul;4(7):e00027. doi: 10.1002/adsr.202500027. Epub 2025 May 22. PMID: 40662140; PMCID: PMC12259227. https://pmc.ncbi.nlm.nih.gov/articles/PMC12259227/ (Full text)

Cytokine profiles associated with persisting symptoms of post-acute sequelae of COVID-19

Abstract:

Background/aims: Post-acute sequelae of COVID-19 (PASC) are highly heterogeneous; therefore, the pathophysiological mechanisms for PASC remain unclear. In this study, we aimed to examine the immunologic aspects of various PASC symptoms.

Methods: We prospectively enrolled adults aged ≥ 18 years who were diagnosed with COVID-19 between August 2022 and September 2023. Blood samples were collected from all participants, who were interviewed using a questionnaire for PASC symptoms at least once between 1 and 6 months after the COVID-19 diagnosis. For immunological evaluation, plasma concentrations of SARS-CoV-2 spike subunit 1-specific IgG and 33 cytokines were measured using enzyme-linked immunosorbent assays and multiplex-based immunoassay, respectively.

Results: In total, 156 pairs of blood samples and symptom reports from 79 participants were eligible for analysis. The most frequent symptom was fatigue, followed by post exertional malaise, chronic cough, thirst, and brain fog. Gastrointestinal symptoms, chest pain, post exertional malaise, smell/taste change, fatigue, brain fog, abnormal movement, and palpitation were accompanied by significant increases in IL-10, VEGF, and inflammatory cytokines like MIP-1α, IL-1β, IL-6, IL-8, MIG, granzyme A, and CX3CL1 levels, while chronic cough, dizziness, dyspnea, and hair loss were not accompanied by significant differences in cytokine levels.

Conclusion: Symptoms classified into different categories based on the dysfunctional organs may share a common pathophysiology regarding elevation of certain cytokines. Although PASC symptoms are heterogeneous, our findings suggest that T-cell recruitment, thrombosis, and increased vascular permeability might contribute to various symptom clusters sharing common pathophysiological mechanisms.

Source: Kwon JS, Chang E, Jang HM, Kim JY, Kim W, Son JY, Cha J, Jang CY, Bae S, Jung J, Kim MJ, Chong YP, Lee SO, Choi SH, Kim YS, Kim SH. Cytokine profiles associated with persisting symptoms of post-acute sequelae of COVID-19. Korean J Intern Med. 2025 Jul;40(4):667-675. doi: 10.3904/kjim.2024.217. Epub 2025 Jul 1. PMID: 40635493. https://kjim.org/journal/view.php?doi=10.3904/kjim.2024.217 (Full text)

Assessing the influence of lived-experience experts on healthcare providers in a virtual community of practice: a qualitative study

Abstract:

Long COVID, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), and other poorly understood post-acute infection syndromes (PAIS) can present with unexplained symptoms or conditions that may be misunderstood by healthcare providers, causing delays in diagnosis and care. To address these issues, the Centers for Disease Control and Prevention (CDC) funded the Long COVID and Fatiguing Illness Recovery Program (LC&FIRP), initiated as a pilot project to assess whether providing tele-mentoring and other online education for primary care providers could help them improve the quality of life and support the recovery of their patients with these conditions.

The LC&FIRP multi-disciplinary team-based care approach is built on the Extension for Community Healthcare Outcomes (ECHO) learning model, which is an evidence-based virtual learning framework developed by the University of New Mexico and designed to disseminate and implement best practices, especially in under-resourced areas. A distinctive feature of LC&FIRP was the inclusion of lived-experience experts. To explore the influence of lived-experience experts on the care patients received, we collected the educational recommendations provided by the lived-experience experts during webinar sessions (January 2022-March 2024) and grouped these by themes.

The major themes that emerged included validation of patients’ illness experience; attitudes and beliefs about Long COVID, ME/CFS, and PAIS; understanding patients’ challenges and communicating with empathy; navigating referrals; recognizing and supporting disability; and supporting self-care. Investigators also interviewed patients of the Family Health Centers of San Diego (FHCSD) about their experiences receiving care from participating primary care providers and employed content analysis methods to code interview transcripts to identify themes among patients’ perspectives. Positive comments from the patients about topics emphasized by the lived-experience experts provided evidence of providers’ uptake and application of the experts’ recommendations and support the value of involving lived-experience experts in medical education to improve health services.

Source: Weaver SS, Carry M, Bertolli J, Godino J, Struminger B, Taren D, Scott JD, Sharp SP, Samaniego J, Bean DR, Issa A, Lin JS, Unger ER, Ramers CB. Assessing the influence of lived-experience experts on healthcare providers in a virtual community of practice: a qualitative study. Front Health Serv. 2025 Jun 27;5:1562651. doi: 10.3389/frhs.2025.1562651. PMID: 40656206; PMCID: PMC12245761. https://pmc.ncbi.nlm.nih.gov/articles/PMC12245761/ (Full text)

Brain and muscle chemistry in myalgic encephalitis/chronic fatigue syndrome (ME/CFS) and long COVID: a 7T magnetic resonance spectroscopy study

Abstract:

Myalgic encephalitis/chronic fatigue syndrome (ME/CFS) is a common debilitating medical condition, whose main symptoms – fatigue, post-exertional malaise and cognitive dysfunction – are also present in many cases of long COVID. Magnetic resonance spectroscopy (MRS) allows the insight into their pathophysiology through exploration of a range of biochemicals putatively relevant to aetiological processes, in particular mitochondrial dysfunction and energy metabolism.

24 patients with ME/CFS, 25 patients with long COVID and 24 healthy controls (HC) underwent brain (pregenual and dorsal anterior cingulate cortex, respectively, pgACC and dACC) and calf muscle MRS scanning at 7 Tesla, followed by a computerised cognitive assessment. Compared to HC, ME/CFS patients had elevated levels of lactate in both pgACC and dACC, while long COVID patients had lowered levels of total choline in dACC. By contrast, skeletal muscle metabolites at rest did not significantly differ between the groups.

The changes in lactate in ME/CFS are consistent with the presence of energetic stress and mitochondrial dysfunction. A reduction in total choline in long COVID is of interest in the context of the recently reported association between blood clots and ‘brain fog’, and earlier animal studies showing that choline might prevent intravascular coagulation.

Importantly, differences in findings between ME/CFS and long COVID suggest that the underlying neurobiological mechanisms, while leading to similar clinical presentations, may differ. An important implication is that patients with ME/CFS and those with fatigue in the course of long COVID should not be studied as a single group, at least until the mechanisms are better understood.

Source: Godlewska BR, Sylvester AL, Emir UE, Sharpley AL, Clarke WT, Williams SR, Gonçalves AJ, Raman B, Valkovič L, Cowen PJ. Brain and muscle chemistry in myalgic encephalitis/chronic fatigue syndrome (ME/CFS) and long COVID: a 7T magnetic resonance spectroscopy study. Mol Psychiatry. 2025 Jul 12. doi: 10.1038/s41380-025-03108-8. Epub ahead of print. PMID: 40652046. https://www.nature.com/articles/s41380-025-03108-8 (Full text)

The impact of leading questions on ME/CFS research: bias and stigma in study design

Abstract:

Background: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex and often misunderstood illness, characterized by post-exertional malaise, unrefreshing sleep, and cognitive impairments.

Objective: To investigate how question phrasing in ME/CFS research may influence participant attributions of fatigue/energy problems and unintentionally reinforce psychosomatic assumptions.

Methods: A total of 2248 individuals with ME/CFS from an international sample completed a survey assessing fatigue-related attributions. We analyzed how question wording influenced whether participants attributed their symptoms to physical or psychosocial causes. Particular focus was given to a fatigue attribution item that framed causes in terms of ‘personal life’ or ‘environmental factors.’

Results: Participants were significantly more likely to attribute their fatigue/energy problems to psychosocial factors when prompted with psychosocial framing. Many respondents who previously indicated physical causes as the primary source of their symptoms shifted to psychosocial explanations in response to the differently phrased item. This shift was especially pronounced among participants reporting higher levels of psychological distress.

Conclusions: Leading or biased question phrasing may distort participant responses in ME/CFS research, potentially inflating psychosomatic interpretations of the illness. Researchers should critically examine survey language to avoid introducing unintended bias that could compromise research validity and reinforce stigma.

Source: Campolattara, A. T. T., Jason, L. A., & Tuzzolino, K. C. (2025). The impact of leading questions on ME/CFS research: bias and stigma in study design. Fatigue: Biomedicine, Health & Behavior, 1–16. https://doi.org/10.1080/21641846.2025.2530338 https://www.tandfonline.com/doi/full/10.1080/21641846.2025.2530338

Beneficial effects of intermittent intravenous saline infusion in dysautonomic patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: a caseseries

Abstract:

Purpose. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating condition with no single, uniformly effective pharmacologic therapy. Dysautonomic features like orthostatic intolerance and postural tachycardia syndrome are common features in ME/CFS, severely affecting the patient´s quality-of-life. Intermittent saline infusion may reduce symptoms associated with dysautonomia, but this has not been tested scientifically in patients with ME/CFS.

In this case-series, 22 patients with ME/CFS and signs of dysautonomia and/or hypovolemia were treated every third week over 9 weeks with intravenous saline (9 mg/mL NaCl), using standard aseptic technique. Symptoms were monitored throughout the treatment regime, and a follow-up evaluation was conducted.

Results. At treatment start, patients were predominantly female (95%), at mean age 46 ± 10 years, and with a mean body hydration percentage of 48 ± 6. Self-reported health status revealed an overall symptom score of 47 ± 13 on a 0-96 scale, a median POTS score of 64 (IQR 16) on a 0-120 scale, and poor measures of quality-of-life (median 25 IQR 25, on a 0-100 scale) and abilityto-work (median 0, IQR 26, on a 0-100 scale). Following 9 weeks of intermittent saline infusion (mean volume 1600 ± 360 mL), self-reported composite symptom score, quality-of-life and POTS-related symptoms improved significantly (all p<0.001), as did ability-to-work (p<0.05).

Our data derived from a non-controlled case-series indicate health benefits from volume loading with intermittent infusion of saline among patients with ME/CFS, which may stimulate further studies on various forms of intravenous volume loading to patients with ME/CFS and dysautonomia.

Source: Per Sjogren, Helena Huhmar, Bo Christer Bertilson, Björn A Bragée, Olli Polo. Beneficial effects of intermittent intravenous saline infusion in dysautonomic patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: a caseseries. Front. Neurol., Sec. Autonomic Disorders, Volume 16 – 2025 | doi: 10.3389/fneur.2025.1601599 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1601599/abstract

SMPDL3B a novel biomarker and therapeutic target in myalgic encephalomyelitis

Abstract:

Background: Sphingomyelin phosphodiesterase acid-like 3B (SMPDL3B) is emerging as a potential biomarker and therapeutic target in myalgic encephalomyelitis (ME), a complex multisystem disorder characterized by immune dysfunction, metabolic disturbances, and persistent fatigue. This study investigates the role of SMPDL3B in ME pathophysiology and explores its clinical relevance.

Methods: A case-control study was conducted in two independent cohorts: a Canadian cohort (249 ME patients, 63 controls) and a Norwegian replication cohort (141 ME patients). Plasma and membrane-bound SMPDL3B levels were quantified using ELISA and flow cytometry. Gene expression of SMPDL3B and PLCXD1, encoding phosphatidylinositol-specific phospholipase C (PI-PLC), was analyzed by qPCR. The effects of dipeptidyl peptidase-4 (DPP-4) inhibitors-vildagliptin, saxagliptin, and linagliptin-on modulation of membrane-bound and soluble SMPDL3B were assessed in vitro by qPCR, flow cytometry and ELISA.

Results: ME patients exhibited significantly elevated plasma SMPDL3B levels, which correlated with symptom severity. Flow cytometry revealed a reduction in membrane-bound SMPDL3B in monocytes, accompanied by increased PLCXD1 expression and elevated plasma levels of PI-PLC and SMPDL3B. These findings suggest that immune dysregulation in ME may be linked to enhanced cleavage of membrane-bound SMPDL3B by PI-PLC. Sex-specific differences were observed, with female ME patients displaying higher plasma SMPDL3B levels, an effect influenced by estrogen. In vitro, estradiol upregulated SMPDL3B expression, indicating hormonal regulation. Vildagliptin and saxagliptin were tested for their potential to inhibit PI-PLC activity independently of their role as DPP-4 inhibitors, and restored membrane-bound SMPDL3B while reduced its soluble form.

Conclusions: SMPDL3B emerges as a key biomarker for ME severity and immune dysregulation, with its activity influenced by hormonal and PI-PLC regulation. The ability of vildagliptin and saxagliptin to preserve membrane-bound SMPDL3B and reduce its soluble form via PI-PLC inhibition suggests a novel therapeutic strategy. These findings warrant clinical trials to evaluate their potential in mitigating immune dysfunction and symptom burden in ME.

Note: See Correction: SMPDL3B a novel biomarker and therapeutic target in myalgic encephalomyelitis

Source: Rostami-Afshari B, Elremaly W, Franco A, Elbakry M, Akoume MY, Boufaied I, Moezzi A, Leveau C, Rompré P, Godbout C, Mella O, Fluge Ø, Moreau A. SMPDL3B a novel biomarker and therapeutic target in myalgic encephalomyelitis. J Transl Med. 2025 Jul 7;23(1):748. doi: 10.1186/s12967-025-06829-0. PMID: 40624584; PMCID: PMC12236014. https://pmc.ncbi.nlm.nih.gov/articles/PMC12236014/ (Full text)

Distinct white matter alteration patterns in post-infectious and gradual onset chronic fatigue syndrome revealed by diffusion MRI

Abstract:

While post-infectious (PI-ME/CFS) and gradual onset (GO-ME/CFS) myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) manifest similar symptoms, it has long been suspected that different disease processes underlie them. However, the lack of biological evidence has left this question unanswered. In this study, how white matter microstructural changes in PI-ME/CFS and GO-ME/CFS patients were investigated.

PI-ME/CFS and GO-ME/CFS patients were recruited based on consensus diagnoses made by two experienced clinicians and compared their diffusion MRI features with those of rigorously matched healthy controls (HCs) with sedentary lifestyles. PI-ME/CFS participants showed significantly higher axial diffusivity (AD) in several association and projection fibres compared to HCs. Higher AD in PI-ME/CFS was significantly related to worse physical health.

In contrast, GO-ME/CFS participants exhibited significantly decreased AD in the corpus callosum. Lower AD in GO-ME/CFS was significantly associated with worse mental health in commissural and projection fibres. No significant group differences were found for fractional anisotropy, mean diffusivity, or radial diffusivity. Distinct patterns of AD alterations in PI-ME/CFS and GO-ME/CFS provide neurophysiological evidence of different disease processes and highlight the heterogeneities of ME/CFS.

Source: Yu Q, Kwiatek RA, Del Fante P, Bonner A, Calhoun VD, Bateman GA, Yamamura T, Shan ZY. Distinct white matter alteration patterns in post-infectious and gradual onset chronic fatigue syndrome revealed by diffusion MRI. Sci Rep. 2025 Jul 7;15(1):24256. doi: 10.1038/s41598-025-09379-z. PMID: 40624094; PMCID: PMC12234658. https://pmc.ncbi.nlm.nih.gov/articles/PMC12234658/ (Full text)

Prevalence and severity of neurologic symptoms in Long-COVID and the role of pre-existing conditions, hospitalization, and mental health

Abstract:

Background: Long-COVID refers to ongoing, relapsing, or new symptoms present 30 or more days after Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. This study examined the prevalence and severity of neurologic symptoms at greater than 1 month following acute SARS-CoV-2 infection and the influence of pre-existing neurologic and psychiatric conditions, current depression and anxiety status, and hospitalization on the presence and severity of these symptoms.

Methods: This prospective cohort study recruited primarily self-referred Long-COVID participants with confirmed SARS-CoV-2 infection. Online questionnaires inquiring about pre-existing conditions, neurologic symptoms and their severity pre, during and post COVID-19, and current anxiety and depression screening were completed by 213 participants at a median time of 8 months after infection. Descriptive analyses and prevalence modeling were performed.

Results: The most frequent neurologic symptoms post COVID-19 were fatigue, concentration/memory difficulties, unrefreshed sleep, and dysarthria/word finding difficulties (73.2–86.4%). Neurologic symptoms were highly prevalent with significantly greater odds post COVID-19 compared to pre for all symptoms and higher prevalence at time periods farther from infection, including those implicit in fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome. Several severe neurologic symptoms were significantly more prevalent post COVID-19. Moderate to severe anxiety (34%) and depression (27%) were observed post COVID-19. Preexisting neurologic or psychiatric conditions did not demonstrate any significant difference in neurologic symptom prevalence post COVID-19. Those who met criteria for moderate or severe anxiety post COVID-19 had a significant difference in prevalence of fatigue, sensitivity to touch and unrefreshed sleep. Similarly, fatigue, concentration/memory difficulty and unrefreshed sleep were more prevalent in moderate to severe depression. There were no significant differences in neurologic symptom prevalence in a hospitalized group when compared to non- hospitalized.

Conclusion: Long-COVID has a high burden of long lasting and severe neurological sequelae. These sequelae are independent of pre-existing self-reported neurologic and psychiatric conditions, as well as previous hospitalization. Current moderate to severe anxiety and depression status can impact fatigue, cognition, and sleep post COVID-19. Focus on the biological impact of SARS-CoV-2 on the nervous system will be essential in ameliorating the tremendous symptom burden left in the wake of the COVID-19 pandemic.

Source: Huff Hanalise V. , Roberts Henry , Bartrum Elizabeth , Norato Gina , Grayson Nicholas , Fleig Katherine , Wilkerson Miciah J. , Stussman Barbara J. , Nath Avindra , Walitt Brian. Prevalence and severity of neurologic symptoms in Long-COVID and the role of pre-existing conditions, hospitalization, and mental health. Frontiers in Neurology, Volume 16 – 2025 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1562084 10.3389/fneur.2025.1562084 ISSN:1664-2295 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1562084/full (Full text)