The weekly research round-up includes recent publications about ME/CFS and Long Covid. We highlight the studies that have particularly caught our interest and follow these with the full list of publications together with their abstracts (summaries).
RESEARCH INDEX
The ME Association maintains a comprehensive index of published research on ME/CFS and Long Covid that is free to use and updated weekly.
Audio Commentary by Dr Katrina Pears
ME/CFS Research Published 8 – 14 November 2022
There have only been four new ME/CFS studies but eighteen studies on Long Covid.
It’s been a particularly busy week for Long Covid research, with two of the papers in the ME/CFS reference section focusing on ME/CFS that has developed following Covid-19 infection (papers one (1) and two (2)), where participants fulfil the diagnostic criteria. Therefore, these are of a slightly different nature as there is a known cause, but shows the increasing recognition for the similarities between ME/CFS and Long Covid.
There is a lack of biological research this week for ME/CFS (which is not a result of a Covid-19 infection), these however, are the two studies we have highlighted this week:
Paper three (3) looks at the recovery story (partially or fully) of 13 young women who had become severely ill in childhood or adolescence in Norway. This study focused on the storytelling of their journeys, particularly how the story was told and structured.
Of the participants that were interviewed for this study eight (out of 13) considered themselves completely recovered, the other five considered themselves much better, with all describing the need for structure and routine in their lives, such as for sleeping and eating, than was needed prior to illness.
While it is reassuring and excellent for those who have recovered and told their stories for this research, I do wonder what percentage of those who became ill in childhood or adolescence this really represents and I do wonder what the true percentage recovery is for this group. Furthermore, resting and pacing is spoken about by the authors as a new phenomenon and not something that was engrained in everyday life throughout the whole journey of ME/CFS. Lastly, it is great to see ME/CFS stories being disseminated but I’m not sure if it’s a good use of an academic journal, where their stories are rigorously analysed, such as comparing the stories between Cornelia and Hedda, Hedda is partially recovered and her story was observed as being “somewhat unfinished and chaotic when compared with Cornelia’s account.” This study might simply be a way for the researchers to increase their published paper numbers. Therefore, this has not added to a greater understanding of ME/CFS.
Paper four (4) examines the different symptoms experienced by Black and White ME/CFS patients. This is the first specific study directly looking at ethnic difference in ME/CFS and is definitely a worthwhile study due to the lack of research in this field. The study used 19 Black patients diagnosed with ME/CFS and compared them with White patients and healthy controls.
Unsurprisingly, ME/CFS patients were seen to be significantly different from controls, but there were few differences between patients who identified as Black or White, which is surprising as previous studies have shown fatigue scores to be higher in Black ethnicities. The findings pointed to Black patients being more impacted by their symptoms, but only one symptom studied was found to be significantly different and that was chest pain.
Despite the huge importance of this study, it is hard to conclude much as it was very small and we don’t know how the different ethnicities are represented in their ethnic groups, furthermore some participants used had a self-reported diagnosis. I feel that this study could have addressed more as the full paper is only six pages long and used only previous data collected in other research at DePaul University (where the researchers are based). This study unfortunately leaves a lot of unanswered questions, such as how ethic groups vary in their susceptibility, obtaining a diagnosis, access to support/services, ability to effectively pace in different communities, prognosis and treatment. Furthermore, answers to these questions probably differ hugely over a global scale and which country the study is conducted in.
I would hope that the DecodeME study could shed more light as well as answering some more of these questions, particularly whether the prevalence in these ethnic groups is higher or lower compared to general population and potential genes involved and environmental factors. However, I fear this group will still be underrepresented.
You may also be interested in reading paper one (1) on the use of transcutaneous vagus nerve stimulation to treat Long Covid Chronic Fatigue Syndrome. While this was a very small pilot study with no control group, a positive response was found with further investigation warranted. Dr Charles Shephard has provided a comment for this study.
ME/CFS Research References and Abstracts
1. Transcutaneous Vagus Nerve Stimulation in the Treatment of Long Covid-Chronic Fatigue Syndrome
Benjamin H Natelson, Michelle Blate, Tiffany Soto
medRxiv [Preprint]
Abstract
Many patients do not recover following Covid infection. The resulting illness is called Long Covid. Because there is no agreed upon treatment for this ailment, we decided to do an open label pilot study using non-invasive, transcutaneous stimulation of the auricular branch of the vagus nerve.
Inclusion criteria required the patient to fulfill criteria for having chronic fatigue syndrome.
Fourteen patients provided evaluable data. Eight of these fulfilled our requirements for treatment success.
Since our criterion for a successful study was that at least a third of patients had to show a positive response to treatment, this was a successful pilot that warrants a follow up study that is appropriately sham controlled.
Nehme, M., Chappuis, F., Kaiser, L. et al.
Journal of general internal medicine (2022).
No Abstract available– this is a short case report. All details are as follows:
Background: Fatigue is common after viral infections, including SARS-CoV-2. Our purpose was to report the prevalence and impact of persistent fatigue 6 months after SARS-CoV-2 infection, considering post-exertional malaise and criteria for chronic fatigue syndrome.
Methods: Since March 2020, individuals tested for SARS-CoV-2 at the Geneva University Hospitals outpatient testing center benefit from remote ambulatory follow-up (COVICARE). This study included all individuals tested between March 2020 and December 2020 and whose follow-up was at 6 months or more after their test date.
Follow-up included questions about the prevalence of symptoms (yes/no) and their severity using a Likert scale (mild, moderate, or severe). Fatigue was assessed using the Eastern Cooperative Oncology Group (ECOG) scale and the Chalder fatigue scale. The Chalder fatigue scale was scored using the 4-item Likert and the bimodal scoring schemes. A score of ≥ 4 on bimodal scoring indicated severe fatigue.
The DePaul brief questionnaire was used to identify post-exertional malaise and criteria for chronic fatigue syndrome.
The Sheehan Disability Scale was used to assess functional impairment. Reduced work capacity was defined as missing days off work or having a reduced productivity on the Sheehan disability scale.
Comorbidities were considered present if pre-existing prior to SARS-CoV-2 infection. Statistical analysis included descriptive comparisons of percentages using chi-square tests and Student’s t test.
Results: Overall, 5515 individuals participated in this study (response rate 70.7%), with 5406 participants at 6 months or more after their test date. A total of 1497 (27.7%) participants had a documented positive SARS-CoV-2 test and were ultimately included in the study. The median time for follow-up was 225 days (interquartile range 207–398). Respectively, fatigue was reported by 17.2%, post-exertional malaise by 8.2%, and the presence of criteria for chronic fatigue syndrome by 1.1% of SARS-CoV-2-positive individuals, compared to 8.9%, 3.5%, and 0.5% of SARS-CoV-2-negative individuals. Characteristics are presented in Table 1.
Out of SARS-CoV-2-positive participants with fatigue (n = 258), 35.3% had moderate to severe limitations on the ECOG scale, and 83.0% had a score ≥ 4 on the Chalder fatigue scale. The Chalder fatigue scale revealed a mean score of 19 out of 33, SD 5.4, and a mean score of 6.7 out of 11, SD 3.3 using bimodal scoring. After adjusting for age and sex, 47.7% of SARS-CoV-2-positive individuals with fatigue at 6 months or more had the frequency and severity criteria for post-exertional malaise, and 6.2% had criteria for chronic fatigue syndrome.
Individuals had a higher prevalence of insomnia, cognitive impairment, headaches, generalized pain, functional impairment, reduced work capacity, and decreased physical activity, after SARS-CoV-2 infection. The prevalence of these sequelae was adjusted for age and sex and was increasingly higher with severe fatigue, with post-exertional malaise, or when criteria for chronic fatigue syndrome were present (Fig. 1).
Discussion: Fatigue is the most common and persistent post-COVID symptom. The spectrum of fatigue severity in post-COVID individuals ranges from feeling tired to having severe fatigue, post-exertional malaise, or criteria for chronic fatigue syndrome with an increasing impact on health, functional capacity, and physical activity.
Almost half of individuals experiencing fatigue at 6 months after the infection had post-exertional malaise, and 6.2% had criteria for chronic fatigue syndrome, prompting physicians to consider pacing as a management option, in the absence of other treatment options at this stage. SARS-CoV-2 infection was positively associated with fatigue and post-exertional malaise.
Results showed that individuals with fatigue were more likely to be vaccinated. This was partially explained by the baseline distribution as older individuals and those with more comorbidities were more likely to get vaccinated.
Results compare to recent reviews showing an overlap between post-COVID condition and chronic fatigue syndrome. Our study graded post-COVID fatigue by severity in correlation with functional capacity, and showed the high prevalence of post-exertional malaise.
Limitations include the self-reported nature of this follow-up with individuals infected in 2020 and follow-up in 2021, lacking comparisons to individuals infected with other variants. Additionally, this study considered having received at least 2 doses as full vaccination, a concept that continues to evolve with time.
Physicians, employers, and insurance companies should address fatigue on a spectrum, accounting for the correlated functional impairment, decreased activity levels, and potentially poorer quality of life.
3. The fragile process of Homecoming – Young women in recovery from severe ME/CFS
Krabbe SH, Groven KS, Schrøder Bjorbækmo W, Sveen U, Mengshoel AM.
Int J Qual Stud Health Well-being. 2023 Dec;18(1):2146244.
Abstract
Purpose: To explore the recovery narratives of 13 young women who had fallen ill with severe Myalgic Encephalomyelitis (ME), also known as Chronic Fatigue Syndrome (CFS), during childhood and adolescence, with the focus on what they had to say about their past experiences from the perspective of the present.
Method: A qualitative narrative approach, informed by a phenomenological theoretical perspective, was adopted to explore what the women found significant and meaningful in their recovery process. Data analysis of in-depth narrative interviews was performed which are presented to readers through the stories of two particular participants.
Results: The first story describes how one participant made a recovery by testing her body's tolerance and working to create a more confident self. The second story describes a complex exploration of possibilities for action in recovery, along with a struggle to make sense of setbacks and hold on to what has been gained.
Conclusion: Recovering from ME/CFS emerges as an inter-personal, contextual, fragile and nonlinear process of homecoming, based on gradually rising bodily based self-knowledge. Illness slowly fades away into the background, and there is the prospect of a healthier tomorrow.
4. Differences in Symptoms among Black and White Patients with ME/CFS
Jason LA, Torres C.
Journal of Clinical Medicine. 2022; 11(22):6708.
Abstract
Study samples of patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) have primarily involved White subjects, so the literature on ethnic differences is sparse.
The current study identified a sample of 19 Black patients diagnosed with ME/CFS and compared them with White patients with ME/CFS, as well as with healthy controls. The studies used a similar psychometrically sound assessment tool to assess symptoms in all subjects.
Findings indicated there were significant differences between patients with ME/CFS versus controls, but few differences between patients who identified as Black or White.
The results suggest there might be few symptom differences between patients with ME/CFS in these two ethnic groups. The implications of these findings are discussed.
Long-COVID Research References
Dr Katrina Pears,
Research Correspondent.
The ME Association.
