Long COVID-19 Syndrome Severity According to Sex, Time from the Onset of the Disease, and Exercise Capacity-The Results of a Cross-Sectional Study

Abstract:

Symptoms of long COVID-19 syndrome (long COVID-19) are reported by 80% of convalescents up to several months after contracting the coronavirus-19 disease (COVID-19). The study aimed to assess the frequency and correlations of long COVID symptoms with sex, disease severity, time since the onset of the disease, and exercise capacity in a population of Polish convalescents hospitalized as a part of a rehabilitation program after COVID-19.

The retrospective analysis was carried out based on medical records concerning reported symptoms, comorbidities, exercise capacity, fatigue and dyspnea on Borg’s scale, arterial oxygen saturation (SpO2), spirometric parameters, chest X-rays/computed tomography scans, systolic pulmonary artery pressure, and left ventricular ejection fraction. The study involved 471 patients aged 63.83 ± 9.93 years who had been hospitalized 191.32 ± 75.69 days from the onset of COVID-19, of which 269 (57.1%) were women. The most common symptoms were fatigue (99.57%), dyspnea (99.36%), and myalgia (97.03%). Women reported more symptoms than men (p < 0.001) and rated their fatigue as more severe (p = 0.021). Patients with depressed moods reported more physical symptoms than others (p < 0.001).

Most long COVID symptoms, including dyspnea, fatigue, and depressive symptoms, were found with the same frequency in patients 12-24 weeks and >24 weeks after recovery (p = 0.874, p = 0.400, and p = 0.320, respectively), regardless of acute COVID-19 severity (p = 0.240, p = 0.826, and p = 0.108, respectively). Dyspnea severity correlated with forced vital capacity (FVC) (r = -0.153, p = 0.005), and forced expiratory volume in one second (FEV1) (r = -0.142, p = 0.008). Fatigue severity correlated with impaired FVC and FEV1 (both r = -0.162, p = 0.003). Fatigue and dyspnea inversely correlated with the distance in a six-minute walk test (r = -0.497, p < 0.001, and r = -0.327, p < 0.001).

In conclusion, in our cohort, long COVID symptoms are more common in women. Dyspnea/fatigue and depressive symptoms do not tend to subside after an average six-month recovery period. The intensity of perceived fatigue may be exaggerated by the coexistence of neuropsychiatric disorders. Increased fatigue and dyspnea correlate with impaired spirometric parameters and significantly affects convalescents’ exercise capacity.

Source: Paradowska-Nowakowska E, Łoboda D, Gołba KS, Sarecka-Hujar B. Long COVID-19 Syndrome Severity According to Sex, Time from the Onset of the Disease, and Exercise Capacity-The Results of a Cross-Sectional Study. Life (Basel). 2023 Feb 11;13(2):508. doi: 10.3390/life13020508. PMID: 36836865; PMCID: PMC9961608. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9961608/ (Full text)

Urine Metabolomics Exposes Anomalous Recovery after Maximal Exertion in Female ME/CFS Patients

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disease with unknown etiology or effective treatments. Post-exertional malaise (PEM) is a key symptom that distinguishes ME/CFS patients. Investigating changes in the urine metabolome between ME/CFS patients and healthy subjects following exertion may help us understand PEM.
The aim of this pilot study was to comprehensively characterize the urine metabolomes of eight female healthy sedentary control subjects and ten female ME/CFS patients in response to a maximal cardiopulmonary exercise test (CPET). Each subject provided urine samples at baseline and 24 h post-exercise. A total of 1403 metabolites were detected via LC-MS/MS by Metabolon® including amino acids, carbohydrates, lipids, nucleotides, cofactors and vitamins, xenobiotics, and unknown compounds.
Using a linear mixed effects model, pathway enrichment analysis, topology analysis, and correlations between urine and plasma metabolite levels, significant differences were discovered between controls and ME/CFS patients in many lipid (steroids, acyl carnitines and acyl glycines) and amino acid subpathways (cysteine, methionine, SAM, and taurine; leucine, isoleucine, and valine; polyamine; tryptophan; and urea cycle, arginine and proline).
Our most unanticipated discovery is the lack of changes in the urine metabolome of ME/CFS patients during recovery while significant changes are induced in controls after CPET, potentially demonstrating the lack of adaptation to a severe stress in ME/CFS patients.
Source: Glass KA, Germain A, Huang YV, Hanson MR. Urine Metabolomics Exposes Anomalous Recovery after Maximal Exertion in Female ME/CFS Patients. International Journal of Molecular Sciences. 2023; 24(4):3685. https://doi.org/10.3390/ijms24043685 https://www.mdpi.com/1422-0067/24/4/3685 (Full text available as PDF file)

Muscle sodium content in patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Background: Muscle fatigue and pain are key symptoms of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Although the pathophysiology is not yet fully understood, there is ample evidence for hypoperfusion which may result in electrolyte imbalance and sodium overload in muscles. Therefore, the aim of this study was to assess levels of sodium content in muscles of patients with ME/CFS and to compare these to healthy controls.

Methods: Six female patients with ME/CFS and six age, BMI and sex matched controls underwent 23Na-MRI of the left lower leg using a clinical 3T MR scanner before and after 3 min of plantar flexion exercise. Sodium reference phantoms with solutions of 10, 20, 30 and 40 mmol/L NaCl were used for quantification. Muscle sodium content over 40 min was measured using a dedicated plugin in the open-source DICOM viewer Horos. Handgrip strength was measured and correlated with sodium content.

Results: Baseline tissue sodium content was higher in all 5 lower leg muscle compartments in ME/CFS compared to controls. Within the anterior extensor muscle compartment, the highest difference in baseline muscle sodium content between ME/CFS and controls was found (mean ± SD; 12.20 ± 1.66 mM in ME/CFS versus 9.38 ± 0.71 mM in controls, p = 0.0034). Directly after exercise, tissue sodium content increased in gastrocnemius and triceps surae muscles with + 30% in ME/CFS (p = 0.0005) and + 24% in controls (p = 0.0007) in the medial gastrocnemius muscle but not in the extensor muscles which were not exercised. Compared to baseline, the increase of sodium content in medial gastrocnemius muscle was stronger in ME/CFS than in controls with + 30% versus + 17% to baseline at 12 min (p = 0.0326) and + 29% versus + 16% to baseline at 15 min (p = 0.0265). Patients had reduced average handgrip strength which was associated with increased average muscle tissue sodium content (p = 0.0319, R2 = 0.3832).

Conclusion: Muscle sodium content before and after exercise was higher in ME/CFS than in healthy controls. Furthermore, our findings indicate an inverse correlation between muscle sodium content and handgrip strength. These findings provide evidence that sodium overload may play a role in the pathophysiology of ME/CFS and may allow for potential therapeutic targeting.

Source: Petter E, Scheibenbogen C, Linz P, Stehning C, Wirth K, Kuehne T, Kelm M. Muscle sodium content in patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. J Transl Med. 2022 Dec 9;20(1):580. doi: 10.1186/s12967-022-03616-z. PMID: 36494667. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-022-03616-z (Full text)

Impaired pulmonary and muscle function during moderate exercise in female patients recovered from SARS-CoV-2

Abstract:

This study aimed to assess pulmonary and muscle dysfunction by analyzing the slow component of oxygen uptake (VO2SC), and mechanical and ventilatory efficiency in adult women recovered from the severe acute respiratory syndrome coronavirus type II (SARS-CoV-2) during a constant load test. 32 women (N = 17 patients with SARS-CoV-2; N = 15 control group) performed two cardiopulmonary exercise tests (CPX) on a cycle ergometer.

In the first test, the participants performed incremental CPX until extenuation. In the second test the participants performed a 10-min CPX at a constant load intensity (watts) corresponding to the first ventilatory threshold. There was a 48-72 h rest period between the two tests. There was a significant increase in the VO2SC in the patients recovered from SARS-CoV-2 (160.4 ± 60 mL min-1) in comparison with the healthy participants (59.6 ± 65 mL min-1) (P < 0.001).

Mechanical efficiency significantly decreased in patients recovered from SARS-CoV-2 compared to the control group (P = 0.04). Ventilatory inefficiency significantly increased in the patients recovered from SARS-CoV-2 compared with the control group (P < 0.001). Adult women recovered from SARS-CoV-2 infection have important pulmonary and muscular dysfunction and fatigue which contributes to increasing the VO2SC and reducing mechanical and ventilatory efficiency during mild-moderate exercise at a constant load.

Source: Pleguezuelos E, Del Carmen A, Moreno E, Ortega P, Robles A, Serra-Prat M, Miravitlles M, Yebenes JC, Garnacho-Castaño MV. Impaired pulmonary and muscle function during moderate exercise in female patients recovered from SARS-CoV-2. Sci Rep. 2022 Dec 4;12(1):20943. doi: 10.1038/s41598-022-24941-9. PMID: 36464697.  https://www.nature.com/articles/s41598-022-24941-9 (Full text)

Single-cell transcriptomics of the immune system in ME/CFS at baseline and following symptom provocation

Summary:

ME/CFS is a serious and poorly understood disease. To understand immune dysregulation in ME/CFS, we used single-cell RNA-seq (scRNA-seq) to examine immune cells in cohorts of patients and controls. Post-exertional malaise (PEM), an exacerbation of symptoms following strenuous exercise, is a characteristic symptom of ME/CFS. Thus, to detect changes coincident with PEM, we also performed scRNA-seq on the same cohorts following exercise. At baseline, ME/CFS patients displayed dysregulation of classical monocytes suggestive of inappropriate differentiation and migration to tissue. We were able to identify both diseased and more normal monocytes within patients, and the fraction of diseased cells correlated with metrics of disease severity. Comparing the transcriptome at baseline and post-exercise challenge, we discovered patterns indicative of improper platelet activation in patients, with minimal changes elsewhere in the immune system. Taken together, these data identify immunological defects present at baseline in patients and an additional layer of dysregulation following exercise.

Highlights ME/CFS is a debilitating disease with unknown causes. Here, we provide, for the first time, an extensive single cell resolution dataset detailing the gene expression programs of circulating immune cells of ME/CFS cases at baseline and after symptom provocation. We were able to detect robust dysregulation in certain immune cells from patients, with dysregulation of classical monocytes manifesting the strongest signal. Indeed, the fraction of aberrant monocytes in ME/CFS patients correlated with the degree of disease severity. Surprisingly, platelet transcriptomes were also altered in ME/CFS, and they were the only component of the immune system that showed large-scale changes following symptom provocation.

Source: Faraz AhmedLuyen Tien VuHongya ZhuDavid Shing Huk IuElizabeth A. FogartyYeonui KwakWeizhong ChenCarl J. FranconiPaul R. MunnSusan M. LevineJared StevensXiangling MaoDikoma C. ShunguGeoffrey E. MooreBetsy A. KellerMaureen R. HansonJennifer K. GrenierAndrew Grimson. Single-cell transcriptomics of the immune system in ME/CFS at baseline and following symptom provocation.

What Primary Care Practitioners Need to Know about the New NICE Guideline for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Adults

Abstract:

The new NICE guideline for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), published in October 2021, makes significant changes in treatment recommendations. It acknowledges the complexity of this chronic medical condition, which always impacts quality of life and can be profoundly disabling, recognising the prejudice and stigma that people with ME/CFS often experience in the absence of any specific diagnostic test.

The guideline outlines steps for accurate diagnosis, recognising post-exertional malaise as a core symptom; importantly, ME/CFS can now be diagnosed after just 3 months in a bid to improve long-term health outcomes. It recommends the need for individual, tailored management by a multi-disciplinary team, ensuring that the wellbeing of the individual is paramount. The guideline makes clear that any programme based on fixed incremental increases in physical activity or exercise, for example graded exercise therapy (GET), should not be offered as a treatment for ME/CFS and emphasises that cognitive behavioural therapy (CBT) should only be offered as a supportive intervention.

Because of the rigorous methodology required by NICE Committee review and the inclusion of the testimony of people with lived experience as committee members, this guideline will influence the future diagnosis and management of ME/CFS in the UK and beyond.

Source:  Kingdon, C.C.; Lowe, A.; Shepherd, C.; Nacul, L. What Primary Care Practitioners Need to Know about the New NICE Guideline for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Adults . Preprints 2022, 2022110016 (doi: 10.20944/preprints202211.0016.v1).  https://www.preprints.org/manuscript/202211.0016/v1 (Full text available as PDF file)

Bias in Exercise Trials for ME/CFS: the Importance of Objective Outcomes and Long-term Follow-up

Sharpe and colleagues recommend that patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) be offered cognitive behavior therapy (CBT) and graded exercise therapy (GET)1, advice that contrasts with recent NICE guidance on ME/CFS.2 The authors argue that “there are many randomized trials indicating the safety and efficacy of these treatments.”1

All of these trials, however, were nonblinded and relied on subjective symptom questionnaires as their main outcomes, a combination that creates a high risk of response bias. Treatment manuals used in these trials included explicit encouragements to raise patients’ expectations of GET and CBT. One patient booklet, for example, informed patients: “You will experience a snowballing effect as increasing fitness leads to increasing confidence in your ability. You will have conquered CFS by your own effort and you will be back in control of your body again.”3 These encouragements were not provided to participants in the control group and might have influenced how patients rated their health. In contrast to what Sharpe and colleagues claim, measuring the expectations of patients before the trial begins, does not address how therapists might have influenced symptom reporting during the trial.

There are further arguments that suggest these trials might have measured response bias rather than improvements in health. There were, for example, no clinically significant differences on objective outcome measures that are less prone to response bias such as employment figures, activity levels, or fitness tests.3 In addition, at long-term follow-up, the control group seemed to perform just as well as participants who received GET or CBT. This could not be explained by additional treatment received after the trial ended.4 These findings are difficult to interpret if patients did indeed rehabilitate successfully following GET or CBT. It is unfortunate that the authors, who were primary researchers in many of these trials, do not address these concerns.

Lastly, Sharpe and colleagues argue that “harm reported from patient community surveys reflects poorly implemented therapy.”1 Patient surveys, however, indicate that ME/CFS patients report harm of GET even if prescribed by a specialist or physiotherapist.5 The authors have previously been challenged for misrepresenting the findings of these surveys.5 Post-exertional malaise or a marked worsening of symptoms when patients exceed their energy limit, is a characteristic feature of ME/CFS.2 There are therefore reasonable safety concerns about treatments such as GET and CBT that try to push patients to exceed their limits.

Read the full article HERE.

Source: Tack, M. Bias in Exercise Trials for ME/CFS: the Importance of Objective Outcomes and Long-term Follow-up. J GEN INTERN MED 37, 3193 (2022). https://doi.org/10.1007/s11606-022-07704-0  (Full text)

Chronic Fatigue Associated with Post-COVID Syndrome versus Transient Fatigue Caused by High-Intensity Exercise: Are They Comparable in Terms of Vascular Effects?

Abstract:

Purpose: The pathophysiology of chronic fatigue associated with post-COVID syndrome is not well recognized. It is assumed that this condition is partly due to vascular dysfunction developed during an acute phase of infection. There is great demand for a diagnostic tool that is able to clinically assess post-COVID syndrome and monitor the rehabilitation process.

Patients and methods: The Flow Mediated Skin Fluorescence (FMSF) technique appears uniquely suitable for the analysis of basal microcirculatory oscillations and reactive hyperemia induced by transient ischemia. The FMSF was used to measure vascular circulation in 45 patients with post-COVID syndrome. The results were compared with those for a group of 26 amateur runners before and after high-intensity exercise as well as for a control group of 32 healthy age-matched individuals.

Results: Based on the observed changes in the NOI (Normoxia Oscillatory Index) and RHR (Reactive Hyperemia Response) parameters measured with the FMSF technique, it was found that chronic fatigue associated with post-COVID syndrome is comparable with transient fatigue caused by high-intensity exercise in terms of vascular effects, which are associated with vascular stress in the macrocirculation and microcirculation. Acute and chronic fatigue symptomatology shared similarly altered changes in the NOI and RHR parameters and both can be linked to calcium homeostasis modification.

Conclusion: The NOI and RHR parameters measured with the FMSF technique can be used for non-invasive clinical assessment of post-COVID syndrome as well as for monitoring the rehabilitation process.

Source: Chudzik M, Cender A, Mordaka R, Zielinski J, Katarzynska J, Marcinek A, Gebicki J. Chronic Fatigue Associated with Post-COVID Syndrome versus Transient Fatigue Caused by High-Intensity Exercise: Are They Comparable in Terms of Vascular Effects? Vasc Health Risk Manag. 2022 Sep 6;18:711-719. doi: 10.2147/VHRM.S371468. PMID: 36097586; PMCID: PMC9464031.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9464031/ (Full text)

Repeated maximal exercise tests of peak oxygen consumption in people with myalgic encephalomyelitis/chronic fatigue syndrome: A systematic review and meta-analysis

Abstract:

Background: Repeated maximal exercise separated by 24 hours may be useful in identifying possible objective markers in people with ME/CFS that are not present in healthy controls.

Aim: We aimed to synthesise studies in which the test-to-retest (24 hours) changes in VO2 and work rate have been compared between people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and controls.

Methods: Seven databases (CINAHL, PubMed, PsycINFO, Web of Knowledge, Embase, Scopus and MEDLINE) were searched. Included studies were observational studies that assessed adults over the age of 18 years with a clinical diagnosis of ME/CFS compared to healthy controls. The methodological quality of included studies was assessed using the Systematic Appraisal of Quality for Observational Research critical appraisal framework. Data from included studies were synthesised using a random effects meta-analysis.

Results: The pooled mean decrease in peak work rate (five studies), measured at retest, was greater in ME/CFS by −8.55 (95% CI −15.38 to –1.72) W. The pooled mean decrease in work rate at anaerobic threshold (four studies) measured at retest was greater in ME/CFS by −21 (95%CI −38 to −4, tau = 9.8) W. The likelihood that a future study in a similar setting would report a difference in work rate at anaerobic threshold which would exceed a minimal clinically important difference (10 W) is 78% (95% CI 40%–91%).

Conclusion: Synthesised data indicate that people with ME/CFS demonstrate a clinically significant test–retest reduction in work rate at the anaerobic threshold when compared to apparently healthy controls.

Source: John Derek Franklin & Michael Graham (2022) Repeated maximal exercise tests of peak oxygen consumption in people with myalgic encephalomyelitis/chronic fatigue syndrome: a systematic review and meta-analysis, Fatigue: Biomedicine, Health & Behavior, DOI: 10.1080/21641846.2022.2108628  https://www.tandfonline.com/doi/full/10.1080/21641846.2022.2108628 (Full text)

Can aquatic exercises contribute to the improvement of the gait stereotype function in patients with Long COVID outcomes?

Abstract:

A variety of rehabilitation programmes can be offered to Long COVID patients, specifically physical training. Indeed 90% of these patients reports impairments of verticalization, stability and spatial orientation, making difficult exercise in the gym. The aim of our study was to assess the effectiveness and safety of aquatic exercise techniques as part of a comprehensive rehabilitation program for patients with Long COVID.

The first of a two-stage program involved development of aquatic exercises technique, which was evaluated in 12 patients with impaired upright posture control before and after exercising by “Habilect” video gait analysis system. During the second phase, effectiveness and safety of aqua exercises were tested in water pool as part of a comprehensive rehabilitation programme conducted in 23 patients with Long COVID outcomes. Physical examination, 6-minute step test, Euro-QL-5D questionnaire, Borg scale, laser Doppler flowmetry, cardiointervalography, and spirometry were performed before and after the aquatic exercises program.

After the training with aquatic exercises, indices of deviations of the main body axes of the head and the body mass centre ameliorated, as well as direction of body movement vector decreased (p<0.05). This study demonstrated a statistically significant improvement in exercise tolerance in both groups, as measured by the 6-minute step test after rehabilitation. The comparison group averaged 236.7 metres [126; 380] (T=8, p=0.047) after the rehabilitation course and the intervention group averaged 233.71 metres [150; 320] (T=8.0, p=0.047). When tested with the Euro-QL-5D questionnaire, a post-treatment improvement was noted in the comparison group on the anxiety/depression subscale (3 [3;3] (T=0, p=0.043)).

In the intervention group, laser Doppler flowmetry revealed a statistically significant increase in microcirculation (6.36 standard units after rehabilitation) [5.54; 8.17] (T=7.0, p=0.004), and a decrease of oxidative metabolism index of 6.89 standard units. [4.76; 6.96] (T=4.0, p=0.03). No serious adverse events were reported. In conclusion, the developed aquatic exercises technique seems to contribute to recovery of impaired upright posture and motor function, normalizing the walking pattern.

Source: Lobanov AA, Irina A Grishechkina, Andronov SV, Gleb N Barashkov, Andrey I Popov, Anatoliy D Fesyun, Elena P Ivanova, Maccarone MC, Stefano Masiero. Can aquatic exercises contribute to the improvement of the gait stereotype function in patients with Long COVID outcomes? Eur J Transl Myol. 2022 Jul 14. doi: 10.4081/ejtm.2022.10698. Epub ahead of print. PMID: 35833897.  https://pubmed.ncbi.nlm.nih.gov/35833897/ (Full text: Follow link on page)