Tag: Unger

Genetic Insights into Circulating Complement Proteins in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Potential Inflammatory Subgroup

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating multi-system illness with heterogeneity that complicates identifying the pathophysiology, biomarkers, and therapeutic targets. Evidence indicates the importance of immune dysregulation, including the complement system, in ME/CFS. This study investigates the contribution of genetic drivers to potential dysregulation of the complement pathway in ME/CFS.

We used protein quantitative trait loci (pQTL) analyses, adjusted for covariates using linear and logistic regression, to identify genetic variants significantly associated with plasma complement protein levels in a study sample identified from the general population (50 ME/CFS and 121 non-fatigued). ME/CFS patients carrying certain pQTLs exhibited dysregulation of the alternative complement pathway, which defined an inflammatory subgroup with a high C3/low Bb profile and established a genetic link to dysregulation of the alternative complement pathway. Six of the significant pQTLs were also associated with fatigue-related phenotypes in the UK Biobank, four of which were complement-associated, providing some validation in an independent population.

Our findings highlight a mechanism by which risk alleles contribute to ME/CFS heterogeneity, providing evidence of a genetic basis for complement dysregulation in a subset of patients. This approach could identify pathway-focused subgroups in ME/CFS and related illnesses to inform personalized approaches to diagnosis and treatment.

Source: Maya J, Unger ER, Lin JS, Rajeevan MS. Genetic Insights into Circulating Complement Proteins in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Potential Inflammatory Subgroup. Int J Mol Sci. 2026 Feb 5;27(3):1574. doi: 10.3390/ijms27031574. PMID: 41683992. https://www.mdpi.com/1422-0067/27/3/1574 (Full text)

Autonomic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Findings from the Multi-Site Clinical Assessment of ME/CFS (MCAM) Study in the USA

Abstract:

Background/Objectives: Symptoms of autonomic dysfunction are common in infection-associated chronic conditions and illnesses (IACCIs), including myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). This study aimed to evaluate autonomic symptoms and their impact on ME/CFS illness severity.
Methods: Data came from a multi-site study conducted in seven ME/CFS specialty clinics during 2012–2020. Autonomic dysfunction was assessed using the Composite Autonomic Symptom Scale 31 (COMPASS-31), medical history, and a lean test originally described by the National Aeronautics and Space Administration (NASA). Illness severity was assessed using Patient-Reported Outcomes Measurement Information System measures, the 36-item short-form, as well as the CDC Symptom Inventory. This analysis included 442 participants who completed the baseline COMPASS-31 assessment, comprising 301 individuals with ME/CFS and 141 healthy controls (HC).
Results: ME/CFS participants reported higher autonomic symptom burden than HC across three assessment tools (all p < 0.0001), including the COMPASS-31 total score (34.1 vs. 6.8) and medical history indicators [dizziness or vertigo (42.6% vs. 2.8%), cold extremities (38.6% vs. 5.7%), and orthostatic intolerance (OI, 33.9% vs. 0.7%)]. Among ME/CFS participants, 97% had at least one autonomic symptom. Those with symptoms in the OI, gastrointestinal, and pupillomotor domains had significantly higher illness severity than those without these symptoms.
Conclusions: ME/CFS patients exhibit a substantial autonomic symptom burden that correlates with greater illness severity. Individualized care strategies targeting dysautonomia assessment and intervention may offer meaningful improvements in symptom management and quality of life for those with ME/CFS and similar chronic conditions.
Source: Issa A, Lin J-MS, Chen Y, Attell J, Brimmer D, Bertolli J, Natelson BH, Lapp CW, Podell RN, Kogelnik AM, et al. Autonomic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Findings from the Multi-Site Clinical Assessment of ME/CFS (MCAM) Study in the USA. Journal of Clinical Medicine. 2025; 14(17):6269. https://doi.org/10.3390/jcm14176269  https://www.mdpi.com/2077-0383/14/17/6269 (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)

Long COVID as an Infection-Associated Chronic Condition: Implications

In-Brief:

A link between infection and chronic illness has been recognized, along with the complexities of interactions between pathogen, environment, host genetics, route of exposure, and timing of outcomes. The COVID-19 pandemic has brought this issue to the forefront and Long COVID is recognized to be an infection associated chronic condition. However, given the wide range of Long COVID presentations, the singular expression gives a false sense of simplicity. Long COVID is best considered as a group of infection associated conditions requiring developing research studies and treatment trials that address the inherent heterogeneity.
Source: Unger ER. Long COVID as an Infection-Associated Chronic Condition: Implications. Am J Health Promot. 2025 Jul;39(6):960-965. doi: 10.1177/08901171241308066b. Epub 2025 Jun 8. PMID: 40485158. https://journals.sagepub.com/doi/10.1177/08901171241308066b (Full text)

Voice of the patient: people with myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) share in their own words

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious, debilitating illness affecting millions of people worldwide. Patients with ME/CFS often feel misunderstood and report facing barriers to healthcare utilization.

Objective: We report on a Voice of the Patient (VOP) series that used tenets from photovoice and hermeneutic phenomenology methods. The approach prioritized respecting and engaging patients as they share individual experiences of living with ME/CFS.

Methods: We developed a 5-step process that could be replicated for interviewing patients in their own words. The process prioritized respecting patients while developing, documenting, and sharing individual accounts of living with ME/CFS. The standardized process for gathering each VOP story enabled individuals to share and participate on their own terms.

Results: Over four years, eight VOP stories were completed and posted on CDC’s ME/CFS website. The stories received over 196,000 page views. Each story was completed in approximately six months. Participants expressed gratitude for the opportunity to share experiences and were appreciative of the process that involved them in the development of stories.

Conclusions: Qualitative methods guided the process for participants taking a central role in sharing stories, which in turn may help educate about patient experiences with ME/CFS. Standardization of steps enabled consistency and transparency. Building flexibility into the process allowed interviewing a range of people with ME/CFS (i.e. bed bound to working) and enabled patients to give narratives in their voice. This process may help to share experiences of people with other chronic diseases or infection associated chronic conditions.

Source: Brimmer DJ, Lin JS, Unger ER. Voice of the patient: people with myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) share in their own words. Fatigue. 2025;13(2):1-11. doi: 10.1080/21641846.2024.2444826. PMID: 40123856; PMCID: PMC11926923. https://pmc.ncbi.nlm.nih.gov/articles/PMC11926923/ (Full text)

Pediatric Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Diagnostic and Communication Case Study for Health Care Providers in Training

Abstract:

Introduction: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic, complex illness. No diagnostic tests exist; illness evaluation relies on medical history, physical exam, and laboratory tests. While more is known about ME/CFS in adults, it can affect children and adolescents as a chronic condition.

Methods: We implemented an ME/CFS pediatric educational activity (diagnosis, management, and communication) with medical, physician assistant, and nursing students at one university and with medical students at a second university. Pretests, two videos and slides, and posttests were completed in approximately 40 minutes. Evaluation included quantitative and qualitative measures for knowledge, attitudes, beliefs, confidence, and clinical information about ME/CFS.

Results: The first group included 31 students who reported low familiarity and clinical exposure to ME/CFS. At posttest, 25 students (81%) recognized ME/CFS as a medical condition compared to seven (23%) at pretest. Using 0-5 scales, mean pretest-to-posttest ability to diagnose increased from 1.0 to 3.5, and confidence to communicate increased from 1.4 to 3.9. The second group, including 26 students pretest and 19 posttest, also reported low familiarity and clinical exposure The posttest showed increased self-rated ability to diagnose (pretest M: 0.6, posttest M: 3.3) and confidence to communicate (pretest M: 1.4, posttest M: 3.7). Qualitative feedback for this group showed understanding of pediatric ME/CFS symptoms, management, and communication.

Discussion: This educational activity increased knowledge of ME/CFS as self-reported ability to make a diagnosis and increased confidence to communicate about pediatric ME/CFS. Participating students showed changes in attitudes towards ME/CFS as a medical condition.

Source: Brimmer DJ, Lin JS, Selinger HA, Issa A, Fall EA, Unger ER. Pediatric Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Diagnostic and Communication Case Study for Health Care Providers in Training. MedEdPORTAL. 2025 Mar 14;21:11507. doi: 10.15766/mep_2374-8265.11507. PMID: 40092054; PMCID: PMC11906784. https://pmc.ncbi.nlm.nih.gov/articles/PMC11906784/ (Full text)

Cognitive assessment in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a cognitive substudy of the multi-site clinical assessment of ME/CFS (MCAM)

Abstract:

Introduction: Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) experience cognitive problems with attention, information processing speed, working memory, learning efficiency, and executive function. Commonly, patients report worsening of cognitive symptoms over time after physical and/or cognitive challenges. To determine, monitor, and manage longitudinal decrements in cognitive function after such exposures, it is important to be able to screen for cognitive dysfunction and changes over time in clinic and also remotely at home. The primary objectives of this paper were: (1) to determine whether a brief computerized cognitive screening battery will detect differences in cognitive function between ME/CFS and Healthy Controls (HC), (2) to monitor the impact of a full-day study visit on cognitive function over time, and (3) to evaluate the impact of exercise testing on cognitive dysfunction.

Methods: This cognitive sub-study was conducted between 2013 and 2019 across seven U.S. ME/CFS clinics as part of the Multi-Site Clinical Assessment of ME/CFS (MCAM) study. The analysis included 426 participants (261 ME/CFS and 165 HC), who completed cognitive assessments including a computerized CogState Brief Screening Battery (CBSB) administered across five timepoints (T0-T4) at the start of and following a full day in-clinic visit that included exercise testing for a subset of participants (182 ME/CFS and 160 HC). Exercise testing consisted of ramped cycle ergometry to volitional exhaustion. The primary outcomes are performance accuracy and latency (performance speed) on the computerized CBSB administered online in clinic (T0 and T1) and at home (T2-T4).

Results: No difference was found in performance accuracy between ME/CFS and HCs whereas information processing speed was significantly slower for ME/CFS at most timepoints with Cohen’s d effect sizes ranging from 0.3-0.5 (p < 0.01). The cognitive decline over time on all CBSB tasks was similar for patients with ME/CFS independent of whether exercise testing was included in the clinic visit.

Conclusion: The challenges of a clinic visit (including cognitive testing) can lead to further cognitive deficits. A single short session of intense exercise does not further reduce speed of performance on any CBSB tasks.

Source: Lange G, Lin JS, Chen Y, Fall EA, Peterson DL, Bateman L, Lapp C, Podell RN, Natelson BH, Kogelnik AM, Klimas NG, Unger ER. Cognitive assessment in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): a cognitive substudy of the multi-site clinical assessment of ME/CFS (MCAM). Front Neurosci. 2024 Nov 1;18:1460157. doi: 10.3389/fnins.2024.1460157. PMID: 39554847; PMCID: PMC11565701. https://pmc.ncbi.nlm.nih.gov/articles/PMC11565701/ (Full text)

Chronic Overlapping Pain Conditions in people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a sample from the Multi-site Clinical Assessment of ME/CFS (MCAM) study

Abstract:

Background: Chronic overlapping pain conditions (COPCs), pain-related conditions that frequently occur together, may occur in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and could impact illness severity. This study aimed to identify comorbid COPCs in patients with ME/CFS and evaluate their impact on illness severity.

Methods: We used data from 923 participants in the Multi-Site Clinical Assessment of ME/CFS study, conducted in seven U.S. specialty clinics between 2012 and 2020, who completed the baseline assessment (595 ME/CFS and 328 healthy controls (HC)). COPCs included chronic low back pain (cLBP), chronic migraine/headache (cMHA), fibromyalgia (FM), interstitial cystitis/irritable bladder (IC/IB), irritable bowel syndrome (IBS), temporomandibular disorder (TMD). Illness severity was assessed through questionnaires measuring symptoms and functioning. Multivariate analysis of variance and analysis of covariance models were used for analyses. Log-binomial regression analyses were used to compute prevalence of COPCs and prevalence ratios (PR) between groups with 95% confidence intervals. Both unadjusted and adjusted results with age and sex are presented.

Results: 76% of participants with ME/CFS had at least one COPCs compared to 17.4% of HC. Among ME/CFS participants, cMHA was most prevalent (48.1%), followed by FM (45.0%), cLBP (33.1%), and IBS (31.6%). All individual COPCs, except TMD, were significantly more frequent in females than males. The unadjusted PR (ME/CFS compared to HC) was highest for FM [147.74 (95% confidence interval (CI) = 20.83-1047.75], followed by cLBP [39.45 (12.73-122.27)], and IC/IB [13.78 (1.88-101.24)]. The significance and order did not change after age and sex adjustment. The COPC comorbidities of cLBP and FM each had a significant impact on most health measures, particularly in pain attributes (Cohen’s d effect size 0.8 or larger). While the impact of COPC comorbidities on non-pain attributes and quality of life measures was less pronounced than that on pain, statistically significant differences between ME/CFS participants with and without COPCs were still evident.

Conclusions: More than 75% of ME/CFS participants had one or more COPCs. Multiple COPCs further exacerbated illness severity, especially among females with ME/CFS. Assessment and management of COPCs may help improve the health and quality of life for patients with ME/CFS.

Source: Fall EA, Chen Y, Lin JS, Issa A, Brimmer DJ, Bateman L, Lapp CW, Podell RN, Natelson BH, Kogelnik AM, Klimas NG, Peterson DL, Unger ER; MCAM Study Group. Chronic Overlapping Pain Conditions in people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a sample from the Multi-site Clinical Assessment of ME/CFS (MCAM) study. BMC Neurol. 2024 Oct 18;24(1):399. doi: 10.1186/s12883-024-03872-0. PMID: 39425035; PMCID: PMC11488184. https://pmc.ncbi.nlm.nih.gov/articles/PMC11488184/ (Full text)

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After SARS-CoV-2 Infection

Abstract:

Importance: Chronic symptoms reported following an infection with SARS-CoV-2, such as cognitive problems, overlap with symptoms included in the definition of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

Objective: To evaluate the prevalence of ME/CFS-like illness subsequent to acute SARS-CoV-2 infection, changes in ME/CFS symptoms through 12 months of follow-up, and the association of ME/CFS symptoms with SARS-CoV-2 test results at the acute infection-like index illness.

Design, setting, and participants: This prospective, multisite, longitudinal cohort study (Innovative Support for Patients with SARS-CoV-2 Infections Registry [INSPIRE]) enrolled participants from December 11, 2020, to August 29, 2022. Participants were adults aged 18 to 64 years with acute symptoms suggestive of SARS-CoV-2 infection who received a US Food and Drug Administration-approved SARS-CoV-2 test at the time of illness and did not die or withdraw from the study by 3 months. Follow-up surveys were collected through February 28, 2023.

Exposure: COVID-19 status (positive vs negative) at enrollment.

Main outcome and measures: The main outcome was the weighted proportion of participants with ME/CFS-like illness based on the 2015 Institute of Medicine clinical case definition using self-reported symptoms.

Results: A total of 4378 participants were included in the study. Most were female (3226 [68.1%]). Mean (SD) age was 37.8 (11.8) years. The survey completion rates ranged from 38.7% (3613 of 4738 participants) to 76.3% (1835 of 4738) and decreased over time. The weighted proportion of participants identified with ME/CFS-like illness did not change significantly at 3 through 12 months of follow-up and was similar in the COVID-19-positive (range, 2.8%-3.7%) and COVID-19-negative (range, 3.1%-4.5%) groups. Adjusted analyses revealed no significant difference in the odds of ME/CFS-like illness at any time point between COVID-19-positive and COVID-19-negative individuals (marginal odds ratio range, 0.84 [95% CI, 0.42-1.67] to 1.18 [95% CI, 0.55-2.51]).

Conclusions and relevance: In this prospective cohort study, there was no evidence that the proportion of participants with ME/CFS-like illness differed between those infected with SARS-CoV-2 vs those without SARS-CoV-2 infection up to 12 months after infection. A 3% to 4% prevalence of ME/CFS-like illness after an acute infection-like index illness would impose a high societal burden given the millions of persons infected with SARS-CoV-2.

Source: Unger ER, Lin JS, Wisk LE, Yu H, L’Hommedieu M, Lavretsky H, Montoy JCC, Gottlieb MA, Rising KL, Gentile NL, Santangelo M, Venkatesh AK, Rodriguez RM, Hill MJ, Geyer RE, Kean ER, Saydah S, McDonald SA, Huebinger R, Idris AH, Dorney J, Hota B, Spatz ES, Stephens KA, Weinstein RA, Elmore JG; Innovative Support for Patients with SARS-CoV-2 Infections Registry (INSPIRE) Group. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After SARS-CoV-2 Infection. JAMA Netw Open. 2024 Jul 1;7(7):e2423555. doi: 10.1001/jamanetworkopen.2024.23555. PMID: 39046739; PMCID: PMC11270135. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270135/ (Full text)

Classification Accuracy and Description of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in an Integrated Health Care System, 2006-2017

Abstract:

Introduction: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic illness characterized by marked functional limitations and fatigue. Electronic health records can be used to estimate incidence of ME/CFS but may have limitations.

Methods: The authors used International Classification of Diseases (ICD) diagnosis codes to identify all presumptive cases of ME/CFS among 9- to 39-year-olds from 2006 to 2017. The authors randomly selected 200 cases for medical record review to classify cases as confirmed, probable, or possible, based on which and how many current clinical criteria they met, and to further characterize their illness. The authors calculated crude annual rates of ME/CFS coding stratified by age and sex using only those ICD codes that had identified confirmed, probable, or possible ME/CFS cases in the medical record review.

Results: The authors identified 522 individuals with presumptive ME/CFS based on having ≥ 1 ICD codes for ME/CFS in their electronic medical record. Of the 200 cases selected, records were available and reviewed for 188. Thirty (15%) were confirmed or probable ME/CFS cases, 39 (19%) were possible cases, 119 (60%) were not cases, and 12 (6%) had no medical record available. Confirmed/probable cases commonly had chronic pain (80%) or anxiety/depression (70%), and only 13 (43%) had completed a sleep study. Overall, 37 per 100,000 had ICD codes that identified confirmed, probable, or possible ME/CFS. Rates increased between 2006 and 2017, with the largest absolute increase among those 30-39 years old.

Conclusions: Using ICD diagnosis codes alone inaccurately estimates ME/CFS incidence.

Source: Liles EG, Irving SA, Koppolu P, Crane B, Naleway AL, Brooks NB, Gee J, Unger ER, Henninger ML. Classification Accuracy and Description of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in an Integrated Health Care System, 2006-2017. Perm J. 2024 Jun 19:1-12. doi: 10.7812/TPP/23.170. Epub ahead of print. PMID: 38980763. https://www.thepermanentejournal.org/doi/10.7812/TPP/23.170 (Full text)