Actigraphic and Genetic Characterization of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Phenotypes in the UK Biobank (P10-9.007)

Abstract:

Objective: Patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) often experience debilitating fatigue and autonomic dysregulation, yet objective measurements of these symptoms are limited. This study utilized actigraphic data from the United Kingdom Biobank (UKBB) to investigate (1) reduced activity in those with CFS, (2) decreased amplitudes of daily temperature rhythms as a potential indicator of autonomic dysregulation, and (3) the impact of specific single nucleotide polymorphisms (SNPs) associated with CFS on these actigraphic parameters.

Background: ME/CFS is a complex and poorly understood condition characterized by profound fatigue, postural orthostasis, and temperature dysregulation. Objective metrics reflecting these fatigue-related symptoms are scarce. Previous research explored small-scale actigraphic analyses, shedding light on movement and temperature patterns in CFS, but large-scale investigations remain limited. Genetic factors have also emerged as potential contributors to CFS risk, although how they affect phenotypic manifestations remains unclear.

Design/Methods: Actigraphic data from the UKBB were analyzed to compare those with CFS (n = 295) to controls (n = 63,133). Movement parameters, acceleration amplitudes, and temperature amplitudes were assessed. Additionally, the impact of specific SNPs associated with CFS on actigraphic measurements and subjective fatigue experiences was examined.

Results: In addition to profound fatigue, those with CFS exhibited significantly reduced overall movement (Cohen’s d = −0.220, p-value = 2.42 × 10–15), lower acceleration amplitudes (Cohen’s d = −0.377, p-value = 1.74 × 10−6), and decreased temperature amplitudes (Cohen’s d = −0.173, p-value = 0.002) compared to controls. Furthermore, certain SNPs associated with CFS were found to significantly influence both actigraphic measurements and subjective fatigue experiences.

Conclusions: This study provides valuable insights into the objective characterization of CFS using actigraphy, shedding light on the interaction between genetics and symptomatology in CFS. The findings offer avenues for further research into the pathophysiology of CFS and may contribute to a better understanding of fatigue-related conditions in general.

Source: Patrick Liu, David Raizen, Carsten Skarke, Thomas Brooks, and Ron Anafi. Actigraphic and Genetic Characterization of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Phenotypes in the UK Biobank (P10-9.007). Neurology, April 9, 2024 issue
102 (17_supplement_1) https://doi.org/10.1212/WNL.0000000000204829 https://www.neurology.org/doi/abs/10.1212/WNL.0000000000204829

Heterogeneity in Measures of Illness among Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Explained by Clinical Practice: A Study in Seven U.S. Specialty Clinics

Abstract:

Background: One of the goals of the Multi-site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM) study was to evaluate whether clinicians experienced in diagnosing and caring for patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) recognized the same clinical entity.
Methods: We enrolled participants from seven specialty clinics in the United States. We used baseline data (n = 465) on standardized questions measuring general clinical characteristics, functional impairment, post-exertional malaise, fatigue, sleep, neurocognitive/autonomic symptoms, pain, and other symptoms to evaluate whether patient characteristics differed by clinic.
Results: We found few statistically significant and no clinically significant differences between clinics in their patients’ standardized measures of ME/CFS symptoms and function. Strikingly, patients in each clinic sample and overall showed a wide distribution in all scores and measures.
Conclusions: Illness heterogeneity may be an inherent feature of ME/CFS. Presenting research data in scatter plots or histograms will help clarify the challenge. Relying on case–control study designs without subgrouping or stratification of ME/CFS illness characteristics may limit the reproducibility of research findings and could obscure underlying mechanisms.
Source: Unger ER, Lin J-MS, Chen Y, Cornelius ME, Helton B, Issa AN, Bertolli J, Klimas NG, Balbin EG, Bateman L, et al. Heterogeneity in Measures of Illness among Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Explained by Clinical Practice: A Study in Seven U.S. Specialty Clinics. Journal of Clinical Medicine. 2024; 13(5):1369. https://doi.org/10.3390/jcm13051369 https://www.mdpi.com/2077-0383/13/5/1369 (Full text)

Development and measurement properties of the PEM/PESE activity questionnaire (PAQ)

Abstract:

Background: Existing instruments often are inappropriate to measure the effects of post-exertional malaise (PEM) and post-exertional symptom exacerbation (PESE) on activities of daily living (ADLs). A validated questionnaire to measure self-reported ability with ADLs would advance research and clinical practice in conditions like myalgic encephalomyelitis and Long Covid.

Objective: Determine the measurement properties of the PEM/PESE Activity Questionnaire (PAQ).

Methods: The PAQ is adapted from the Patient Specific Functional Scale. Respondents rated three self-selected ADLs on two 0-100 scales, including current performance compared to (1) a ‘good day’ and (2) before illness. Respondents provided a Burden of Functioning rating on a 0-100 scale, anchored at 0 being the activity took “No time, effort, and resources at all” and 10 being “All of my time, effort, and resources.” Respondents took the PAQ twice, completing a demographic questionnaire after the first PAQ and before the second PAQ. Descriptive statistics and intraclass correlation coefficients were calculated for each scale to assess test-retest reliability. Minimum detectable change outside the 95% confidence interval (MDC95) was calculated. Ceiling and floor effects were determined when the MDC95 for average and function scores crossed 0 and 100, respectively.

Results: n = 981 responses were recorded, including n = 675 complete surveys. Test-retest reliability was generally fair to excellent, depending on function and scale. MDC95 values generally indicated scale responsiveness. Ceiling and floor effects were noted infrequently for specific functions.

Conclusion: The PAQ is valid, reliable, and sensitive. Additional research may explore measurement properties involving functions that were infrequently selected in this sample.

Source: Davenport TE, Stevens SR, Stevens J, Snell CR, Van Ness JM. Development and measurement properties of the PEM/PESE activity questionnaire (PAQ). Work. 2023 Mar 13. doi: 10.3233/WOR-220553. Epub ahead of print. PMID: 36938768. https://content.iospress.com/articles/work/wor220553 (Full text)

Activity monitoring and patient-reported outcome measures in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients

Abstract:

Introduction: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a disease with no validated specific and sensitive biomarker, and no standard approved treatment. In this observational study with no intervention, participants used a Fitbit activity tracker. The aims were to explore natural symptom variation, feasibility of continuous activity monitoring, and to compare activity data with patient reported outcome measures (PROMs).

Materials and methods: In this pilot study, 27 patients with mild to severe ME/CFS, of mean age 42.3 years, used the Fitbit Charge 3 continuously for six months. Patients wore a SenseWear activity bracelet for 7 days at baseline, at 3 and 6 months. At baseline and follow-up they completed the Short Form 36 Health Survey (SF-36) and the DePaul Symptom Questionnaire-Short Form (DSQ-SF).

Results: The mean number of steps per day decreased with increasing ME/CFS severity; mild 5566, moderate 4991 and severe 1998. The day-by-day variation was mean 47% (range 25%-79%). Mean steps per day increased from the first to the second three-month period, 4341 vs 4781 steps, p = 0.022. The maximum differences in outcome measures between 4-week periods (highest vs lowest), were more evident in a group of eight patients with milder disease (baseline SF-36 PF > 50 or DSQ-SF < 55) as compared to 19 patients with higher symptom burden (SF-36 PF < 50 and DSQ-SF > 55), for SF-36 PF raw scores: 16.9 vs 3.4 points, and for steps per day: 958 versus 479 steps. The correlations between steps per day and self-reported SF-36 Physical function, SF-36 Social function, and DSQ-SF were significant. Fitbit recorded significantly higher number of steps than SenseWear. Resting heart rates were stable during six months.

Conclusion: Continuous activity registration with Fitbit Charge 3 trackers is feasible and useful in studies with ME/CFS patients to monitor steps and resting heart rate, in addition to self-reported outcome measures.

Source: Rekeland IG, Sørland K, Bruland O, Risa K, Alme K, Dahl O, Tronstad KJ, Mella O, Fluge Ø. Activity monitoring and patient-reported outcome measures in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients. PLoS One. 2022 Sep 19;17(9):e0274472. doi: 10.1371/journal.pone.0274472. PMID: 36121803. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0274472 (Full text)

Physical Activity Measures in Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Correlations Between Peak Oxygen Consumption, the Physical Functioning Scale of the SF-36 Questionnaire, and the Number of Steps From an Activity Meter

Abstract:

Background: Most studies to assess effort intolerance in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) have used questionnaires. Few studies have compared questionnaires with objective measures like an actometer or an exercise test. This study compared three measures of physical activity in ME/CFS patients: the physical functioning scale (PFS) of the SF-36, the number of steps/day (Steps) using an actometer, and the %peak VO2 of a cardiopulmonary stress test.

Methods: Female ME/CFS patients were selected from a clinical database if the three types of measurements were available, and the interval between measurements was ≤ 3 months. Data from the three measures were compared by linear regression.

Results: In 99 female patients the three different measures were linearly, significantly, and positively correlated (PFS vs Steps, PFS vs %peak VO2 and Steps vs %peak VO2: all P < 0.001). Subgroup analysis showed that the relations between the three measures were not different in patients with versus without fibromyalgia and with versus without a maximal exercise effort (RER ≥ 1.1). In 20 patients re-evaluated for symptom worsening, the mean of all three measures was significantly lower (P < 0.0001), strengthening the observation of the relations between them. Despite the close correlation, we observed a large variation between the three measures in individual patients.

Conclusions: Given the large variation in ME/CFS patients, the use of only one type of measurement is inadequate. Integrating the three modalities may be useful for patient care by detecting overt discrepancies in activity and may inform studies that compare methods of improving exercise capacity.

Source: van Campen CMC, Rowe PC, Verheugt FWA, Visser FC. Physical activity measures in patients with myalgic encephalomyelitis/chronic fatigue syndrome: correlations between peak oxygen consumption, the physical functioning scale of the SF-36 questionnaire, and the number of steps from an activity meter. J Transl Med. 2020;18(1):228. Published 2020 Jun 8. doi:10.1186/s12967-020-02397-7 https://pubmed.ncbi.nlm.nih.gov/32513266/

Preliminary ICF Core Set for Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Rehabilitation Medicine

Abstract:

Objective: To create and evaluate a preliminary ICF Core Set for myalgic encephalomyelitis/chronic fatigue syndrome using a team-based approach.

Design: Observational study.

Subjects/patients: A total of 100 consecutive patients (mean age 45 years, standard deviation (SD) 9 years) were assessed by a rehabilitation team and included in the study.

Methods: A preliminary International Classification of Functioning, Disability and Health (ICF) Core Set was created, based on literature studies, and on discussion forums between the team and the researchers. Patients were assessed by a rehabilitation medicine team regarding impairments in body function, activity limitations, and restrictions in participation.

Results: Clinical assessments of the component Body Functions found impairments in energy, fatigue, physical endurance, fatigability, sleep and pain in 82-100% of patients. At least half of the patients had impairments in higher cognitive functions, attention, and emotions, as well as sound and light hypersensitivity, general hyper-reactivity and thermoregulatory functions. For the component Activity/Participation, the most frequent limitations and restrictions were in doing housework (93%), assisting others (92%), acquisition of goods and services (90%), remunerative employment (87%), handling stressful situations (83%), preparing food (83%), recreation and leisure (82%), informal socializing (78%) and carrying out daily activities (77%). The most frequent degrees of impairments/limitations/restrictions assessed were light and moderate, except for remunerative employment, for which restrictions were severe.

Conclusion: Using unconventional methods, this study sets out a preliminary ICF Core Set list for patients with myalgic encephalomyelitis/chronic fatigue syndrome. Further studies are required to improve and test this Core Set in myalgic encephalomyelitis/chronic fatigue syndrome populations.

Source: Bileviciute-Ljungar I, Schult ML, Borg K, Ekholm J. Preliminary ICF core set for patients with myalgic encephalomyelitis/chronic fatigue syndrome in rehabilitation medicine [published online ahead of print, 2020 May 28]. J Rehabil Med. 2020;10.2340/16501977-2697. doi:10.2340/16501977-2697 https://www.medicaljournals.se/jrm/content/abstract/10.2340/16501977-2697 (Full text)

Assessing current functioning as a measure of significant reduction in activity level

Abstract:

BACKGROUND: Myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) have case definitions with varying criteria, but almost all criteria require an individual to have a substantial reduction in activity level. Unfortunately, a consensus has not been reached regarding what constitutes substantial reductions. One measure that has been used to measure substantial reduction is the Medical Outcomes Study Short Form-36 Health Survey (SF-36).[1].

PURPOSE: The current study examined the relationship between the SF-36, a measure of current functioning, and a self-report measure of the percent reduction in hours spent on activities.

RESULTS: Findings indicated that select subscales of the SF-36 accurately measure significant reductions in functioning. Further, this measure significantly differentiates patients from controls.

CONCLUSION: Determining what constitutes a significant reduction in activity is difficult because it is subjective to the individual. However, certain subscales of the SF-36 could provide a uniform way to accurately measure and define substantial reductions in functioning.

 

Source: Thorpe T, McManimen S, Gleason K, Stoothoff J, Newton JL, Strand EB, Jason LA. Assessing current functioning as a measure of significant reduction in activity level. Fatigue. 2016;4(3):175-188. doi: 10.1080/21641846.2016.1206176. Epub 2016 Jul 19. https://www.ncbi.nlm.nih.gov/pubmed/28217427

 

Measuring substantial reductions in activity

Abstract:

The case definitions for Myalgic Encephalomyelitis/chronic fatigue syndrome (ME/CFS), ME, and CFS each include a disability criterion requiring substantial reductions in activity in order to meet diagnostic criteria. Difficulties have been encountered in defining and operationalizing the substantial reduction disability criterion within these various illness definitions.

The present study sought to relate measures of past and current activities in several domains including the SF-36, an objective measure of activity (e.g., actigraphy), a self-reported quality of life scale, and measures of symptom severity.

Results of the study revealed that current work activities had the highest number of significant associations with domains such as the SF-36 subscales, actigraphy, and symptom scores. As an example, higher self-reported levels of current work activity were associated with better health. This suggests that current work related activities may provide a useful domain for helping operationalize the construct of substantial reductions in activity.

 

Source: Schafer C, Evans M, Jason LA, So S, Brown A. Measuring substantial reductions in activity. J Prev Interv Community. 2015;43(1):5-19. doi: 10.1080/10852352.2014.973242. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4295629/ (Full article)