Fatigue and perceived fatigability, not objective fatigability, are prevalent in people with post-COVID-19

Somatosensory processing in long COVID fatigue and its relations with physiological and psychological factors

Fatigue is prevalent amongst people with long COVID, but is poorly understood. The sensory attenuation framework proposes that impairments in sensory processing lead to heightened perception of effort, driving fatigue. This study aims to investigate the role of somatosensory processing impairments in long COVID fatigue and quantify how sensory processing relates to other prominent symptoms of long COVID including autonomic dysfunction, mood and illness beliefs in driving the experience of fatigue. We will recruit 44 individuals with long COVID fatigue and 44 individuals with neither long COVID nor fatigue (controls). Our primary objective is to compare baseline somatosensory processing between individuals with long COVID fatigue and controls. Additionally, we will explore the associations between somatosensory processing, fatigability and the level of fatigue induced by cognitive and physical exertion. Due to the complex nature of fatigue, we will also investigate how long COVID, state fatigue, perceived effort, mood, illness beliefs, autonomic symptoms and autonomic nervous system function interact to predict trait fatigue. This comprehensive investigation aims to elucidate how sensory processing and other prominent symptoms interact to impact the experience of fatigue.

Fatigue in healthcare workers with mild COVID-19 survivors in Indonesia

Persistent symptoms after the coronavirus disease 2019 (COVID-19, known as post-COVID syndrome (PCS), presented an ongoing health burden among COVID-19 survivors, including health workers. The existence of fatigue in mild COVID-19 survivors has not been widely reported. The aim of this study was to present the symptoms of fatigue in healthcare workers who experienced mild COVID-19 and the factors associated with fatigue. A cross-sectional study was conducted at H. Adam Malik General Hospital in Medan, Indonesia, from September to December 2022, included doctors, nurses, ancillary workers, and medical support workers who experienced mild COVID-19. Fatigue was measured by a fatigue assessment scale (FAS). The assessed possible risk factors were gender, age, vaccination history, comorbid, presence of PCS, duration of PCS symptoms, and number of PCS symptoms. The Chi-squared or Fisher's exact tests were used to assess the association between the incidence of fatigue and risk factors. A total of 100 healthcare workers of mild COVID-19 survivors were included. Most of them were nurses (58%), women (81%), and aged 19-30 years old (36%). The majority had incomplete vaccination history (64%), experienced PCS (71%), no comorbidities (61%), and experienced <3 months of PCS symptoms (55%). Mild to moderate fatigue was found in 23% of healthcare workers and only 1% experienced severe fatigue. No significant association was found between gender, vaccination history, and comorbidities with the incidence of fatigue. However, a significant association was observed between age (p=0.021), the presence of PCS (p=0.041), and the number of PCS symptoms (p=0.047) with fatigue incidence. Furthermore, there were significant associations between symptoms of PCS (confusion (p=0.004), insomnia (p=0.001), myalgia (p=0.035), arthralgia (p=0.028), throat pain (p=0.042), headache (p=0.042), and chest pain (p=0.011)) with fatigue. These findings can contribute to providing the necessary support for mild COVID-19 survivors and persistent fatigue.

Decoding Post-Viral Fatigue: The Basal Ganglia's Complex Role in Long-COVID

Long-COVID afflicts millions with relentless fatigue, disrupting daily life. The objective of this narrative review is to synthesize current evidence on the role of the basal ganglia in long-COVID fatigue, discuss potential mechanisms, and highlight promising therapeutic interventions. A comprehensive literature search was conducted using PubMed, Scopus, and Web of Science databases. Mounting evidence from PET, MRI, and functional connectivity data reveals basal ganglia disturbances in long-COVID exhaustion, including inflammation, metabolic disruption, volume changes, and network alterations focused on striatal dopamine circuitry regulating motivation. Theories suggest inflammation-induced signaling disturbances could impede effort/reward valuation, disrupt cortical-subcortical motivational pathways, or diminish excitatory input to arousal centers, attenuating drive initiation. Recent therapeutic pilots targeting basal ganglia abnormalities show provisional efficacy. However, heterogeneous outcomes, inconsistent metrics, and perceived versus objective fatigue discrepancies temper insights. Despite the growing research, gaps remain in understanding the precise pathways linking basal ganglia dysfunction to fatigue and validating treatment efficacy. Further research is needed to advance understanding of the basal ganglia's contribution to long-COVID neurological sequelae and offer hope for improving function across the expanding affected population.

Amantadine and/or transcranial magnetic stimulation for fatigue associated with multiple sclerosis (FETEM): study protocol for a phase 3 randomised, double-blind, cross-over, controlled clinical trial

INTRODUCTION

Fatigue is one of the most disabling symptoms of multiple sclerosis (MS), and effective treatments are lacking. Amantadine is one of the most used treatments, although its efficacy is under debate. Transcranial magnetic stimulation (TMS) is a promising intervention that has shown positive effects in some preliminary investigations. We aim to investigate the effect of 6 weeks of amantadine and/or TMS in fatigue due to MS.

METHODS AND ANALYSIS

The study is a national, multicentre, phase 3, randomised, double-blind, cross-over, placebo-controlled and sham-controlled clinical trial. Adult patients with relapsing-remitting MS, Expanded Disability Status Scale score of 1.5-4.5 and Fatigue Severity Score>4 are eligible for the trial. Participants will be randomised to one of the sequences of the study. Each sequence consists of four periods of 6 weeks of treatment and three washout periods of 12-18 weeks. All patients will receive all the combinations of therapies. The primary outcome is the Modified Fatigue Impact Scale. The secondary outcomes are the Symbol Digit Modalities Test (cognition), Beck Depression Inventory-II (depressive symptoms) and Short-Survey 12 (quality of life). Safety and cost-effectiveness will also be evaluated. An exploratory substudy including MRI and blood biomarkers will be conducted.

ETHICS AND DISSEMINATION

The study is approved by the Ethics Committee of the Hospital Clinico San Carlos and the Spanish Agency of Medications and Medical Devices. All study findings will be published in scientific peer-reviewed journals and presented at relevant scientific conferences.

TRIAL REGISTRATION NUMBER

EudraCT 2021-004868-95; NCT05809414.

Effectiveness of Functional or Aerobic Exercise Combined With Breathing Techniques in Telerehabilitation for Patients With Long COVID: A Randomized Controlled Trial

OBJECTIVE

The aim of this study was to compare the short-term clinical effects of 2 telerehabilitation programs, functional versus aerobic exercises (AEs), both combined with breathing techniques, regarding the improvement of long coronavirus disease 2019 (COVID-19) symptoms.

METHODS

A randomized controlled trial was conducted. The participants were assigned randomly to either the functional exercise (FE) group or AE group, both including breathing techniques. The interventions lasted for 8 weeks with 3 sessions per week, and they were conducted through the Fisiotrack mobile phone application. Assessments were performed at baseline and after treatment, including testing fatigue (Fatigue Assessment Scale), dyspnea (London Chest Activity of Daily Living Scale), functional performance (30 Seconds Standing Test), perceived stress (Perceived Stress Scale), anxiety and depression (Hospital Anxiety and Depression Questionnaire), and quality of life (European Quality of Life Scale). The perceived change after treatment (Patient Global Impression of Change Scale), the usability of the application (System Usability Scale), and the adherence to treatment were also examined after treatment.

RESULTS

In total, 43 participants (FE group, n = 21; AE group, n = 22; mean age = 42.4 [SD = 6.5] years) completed the study. In the intragroup comparison, the FE group showed improved fatigue (-6.7 points; 95% CI = -11.9 to -1.3), functional capacity (2.6 repetitions; 95% CI = 0.3 to 4.9), and perceived stress (-4.9 points; 95% CI = -9.1 to 0.8), while the AE group showed improved perceived stress (-6.2 points; 95% CI = -10.3 to -2.1). No significant differences in the intergroup effect were identified for the studied variables. Significant differences were observed in the Patient Global Impression of Change Scale in favor of the FE group compared to the AE group, and quality of life reached the minimal clinically important difference for both groups. The ease of use of the telerehabilitation tool was rated excellent in both groups.

CONCLUSIONS

Both telerehabilitation exercise modalities are effective at improving stress symptoms and quality of life in patients with long COVID-19. For improving fatigue and functional performance, FE shows more promising results.

IMPACT

FE or AE may be recommended depending on patients' symptoms, and both may improve quality of life and stress symptoms in patients with long COVID-19. Telerehabilitation may be an optimal intervention modality for the prescription of physical exercise in patients with long COVID-19.

The long-term health outcomes, pathophysiological mechanisms and multidisciplinary management of long COVID

There have been hundreds of millions of cases of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). With the growing population of recovered patients, it is crucial to understand the long-term consequences of the disease and management strategies. Although COVID-19 was initially considered an acute respiratory illness, recent evidence suggests that manifestations including but not limited to those of the cardiovascular, respiratory, neuropsychiatric, gastrointestinal, reproductive, and musculoskeletal systems may persist long after the acute phase. These persistent manifestations, also referred to as long COVID, could impact all patients with COVID-19 across the full spectrum of illness severity. Herein, we comprehensively review the current literature on long COVID, highlighting its epidemiological understanding, the impact of vaccinations, organ-specific sequelae, pathophysiological mechanisms, and multidisciplinary management strategies. In addition, the impact of psychological and psychosomatic factors is also underscored. Despite these crucial findings on long COVID, the current diagnostic and therapeutic strategies based on previous experience and pilot studies remain inadequate, and well-designed clinical trials should be prioritized to validate existing hypotheses. Thus, we propose the primary challenges concerning biological knowledge gaps and efficient remedies as well as discuss the corresponding recommendations.

Reported neurological symptoms after severe acute respiratory syndrome coronavirus type 2 infection: A systematic diagnostic approach

BACKGROUND AND PURPOSE

Following increasing demands of patients with suspected neurological symptoms after infection with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), the Department of Neurology at the Medical University of Vienna established a new outpatient clinic to systematically assess, diagnose, and document neurological complaints potentially associated with a prior SARS-CoV-2 infection.

METHODS

The data presented here include prospectively collected 156 outpatients from May 2021 to April 2022. Patients underwent semistandardized interviewing about symptoms with reported onset after SARS-CoV-2 infection, neurological examination, and comprehensive diagnostic workup.

RESULTS

Reported new onset symptoms after infection included fatigue (77.6%), subjective cognitive impairment (72.4%), headache (47.7%), loss of smell and/or taste (43.2%), and sleep disturbances (42.2%). Most patients had a mild coronavirus disease (COVID-19) disease course (84%) and reported comorbidities (71%), of which the most frequent were psychiatric disorders (34%). Frequency of symptoms was not associated with age, sex, or severity of COVID-19 course. A comprehensive diagnostic workup revealed no neurological abnormalities in the clinical examination, or electrophysiological or imaging assessments in the majority of patients (n = 143, 91.7%). Neuropsychological assessment of a subgroup of patients (n = 28, 17.9%) showed that cognitive impairments in executive functions and attention, anxiety, depression, and somatization symptoms were highly common.

CONCLUSIONS

In this systematic registry, we identified fatigue, cognitive impairment, and headache as the most frequently reported persisting complaints after SARS-CoV-2 infection. Structural neurological findings were rare. We also suspect a link between the growing burden of the COVID-19 pandemic on personal lives and the increase in reported neurological and psychiatric complaints.

[The structure of post/long COVID fatigue syndrome. Prospects for correction]

AIM

To study the features of post-COVID asthenic syndrome and evaluate the effectiveness of the drug containing the succinic acid complex with trimethylhydrazinium in its treatment.

MATERIALS AND METHODS

A prospective, multicenter, comparative, randomized, double-blind, placebo-controlled study of the efficacy of sequential therapy with BRAINMAX® included 160 patients with a history of coronavirus infection within 12 to 16 weeks (not more than 12 months). The study was conducted at 6 healthcare centers in different regions of the Russian Federation. Testing was performed on the following scores: VAS for headache score, MFI-20 asthenia score, PSQI test, FAS-10 fatigue score, DHI dizziness score, MoCA cognitive impairment score, Beck anxiety score, vegetative index of Kerdo.

RESULTS

PSQI questionnaire showed significant improvement in sleep quality in the study group: by -2.5 points [-4; -1] (p<0.001); there was a more pronounced significant decrease in the MFI-20 score of -19.5 points [-27; -11] (p<0.001); a significant decrease in the FAS-10 fatigue score by -9 [-13.5; -4] points (p<0.001); DHI dizziness score showed a decrease by -6 [-12; 0] points in the BRAINMAX® group (p=0.001); the score of Beck anxiety and depression scale decreased by -5 [-11; -2] points (p<0.001). Multiple linear regression data showed a significant increase of 0.56 (p=0.02) in the MoCA score.

CONCLUSION

Our study convincingly showed the effectiveness of therapy with BRAINMAX® in a wide range of symptoms in patients with the post-COVID syndrome.

[Role of psychological factors in post-COVID-19 condition]

Even after a mild episode of coronavirus disease 2019 (COVID-19), many patients suffer from persistent symptoms that can impair their quality of life for months. The potential role of psychological mechanisms in this post-COVID-19 condition, often referred to as long COVID, has been discussed early in the pandemic. Evidence supporting this hypothesis is now accumulating. First, a history of anxiety or depression is now an established risk factor for post-COVID-19 condition with a dose-response relationship and effect size similar to those of other known risk factors. This association extends to other forms of psychological distress, including perceived stress and loneliness. Second, specific beliefs about COVID-19 have been associated with the risk of subsequent similar symptoms, occurring weeks to several months later. Other studies, which have yet to be replicated, suggest an influence of the context of the initial infection (first versus second wave of the pandemic, before the emergence of significant variants and vaccination) and the trust in various sources of information about COVID-19 on the risk of subsequent symptoms. Bayesian models of perception can account for these results particularly well within a theoretical framework similar to that advanced for functional somatic disorders, integrating increased symptom expectations with decreased perception of the body internal state (interoception) and intolerance of uncertainty in the context of symptoms initially triggered by an infectious episode. These psychological mechanisms should obviously not be considered as exclusive. However, since they are modifiable, they could be targeted in clinical trials, within an integrative and multidisciplinary approach.

Effect of Post-COVID-19 on Brain Volume and Glucose Metabolism: Influence of Time Since Infection and Fatigue Status

Post-COVID-19 syndrome (PCS) fatigue is typically most severe <6 months post-infection. Combining magnetic resonance imaging (MRI) and positron emission tomography (PET) imaging with the glucose analog [¹⁸F]-Fluorodeoxyglucose (FDG) provides a comprehensive overview of the effects of PCS on regional brain volumes and metabolism, respectively. The primary purpose of this exploratory study was to investigate differences in MRI/PET outcomes between people < 6 months (N = 18, 11 female) and > 6 months (N = 15, 6 female) after COVID-19. The secondary purpose was to assess if any differences in MRI/PET outcomes were associated with fatigue symptoms. Subjects > 6 months showed smaller volumes in the putamen, pallidum, and thalamus compared to subjects < 6 months. In subjects > 6 months, fatigued subjects had smaller volumes in frontal areas compared to non-fatigued subjects. Moreover, worse fatigue was associated with smaller volumes in several frontal areas in subjects > 6 months. The results revealed no brain metabolism differences between subjects > 6 and < 6 months. However, both groups exhibited both regional hypo- and hypermetabolism compared to a normative database. These results suggest that PCS may alter regional brain volumes but not metabolism in people > 6 months, particularly those experiencing fatigue symptoms.

Measuring objective fatigability and autonomic dysfunction in clinical populations: How and why?

Fatigue is a major symptom in many diseases, often among the most common and severe ones and may last for an extremely long period. Chronic fatigue impacts quality of life, reduces the capacity to perform activities of daily living, and has socioeconomical consequences such as impairing return to work. Despite the high prevalence and deleterious consequences of fatigue, little is known about its etiology. Numerous causes have been proposed to explain chronic fatigue. They encompass psychosocial and behavioral aspects (e.g., sleep disorders) and biological (e.g., inflammation), hematological (e.g., anemia) as well as physiological origins. Among the potential causes of chronic fatigue is the role of altered acute fatigue resistance, i.e. an increased fatigability for a given exercise, that is related to physical deconditioning. For instance, we and others have recently evidenced that relationships between chronic fatigue and increased objective fatigability, defined as an abnormal deterioration of functional capacity (maximal force or power), provided objective fatigability is appropriately measured. Indeed, in most studies in the field of chronic diseases, objective fatigability is measured during single-joint, isometric exercises. While those studies are valuable from a fundamental science point of view, they do not allow to test the patients in ecological situations when the purpose is to search for a link with chronic fatigue. As a complementary measure to the evaluation of neuromuscular function (i.e., fatigability), studying the dysfunction of the autonomic nervous system (ANS) is also of great interest in the context of fatigue. The challenge of evaluating objective fatigability and ANS dysfunction appropriately (i.e.,. how?) will be discussed in the first part of the present article. New tools recently developed to measure objective fatigability and muscle function will be presented. In the second part of the paper, we will discuss the interest of measuring objective fatigability and ANS (i.e. why?). Despite the beneficial effects of physical activity in attenuating chronic fatigue have been demonstrated, a better evaluation of fatigue etiology will allow to personalize the training intervention. We believe this is key in order to account for the complex, multifactorial nature of chronic fatigue.