Fatigue and symptom-based clusters in post COVID-19 patients: a multicentre, prospective, observational cohort study.

BACKGROUND: In the Netherlands, the prevalence of post COVID-19 condition is estimated at 12.7% at 90-150 days after SARS-CoV-2 infection. This study aimed to determine the occurrence of fatigue and other symptoms, to assess how many patients meet the Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) criteria, to identify symptom-based clusters within the P4O2 COVID-19 cohort and to compare these clusters with clusters in a ME/CFS cohort. METHODS: In this multicentre, prospective, observational cohort in the Netherlands, 95 post COVID-19 patients aged 40-65 years were included. Data collection at 3-6 months after infection included demographics, medical history, questionnaires, and a medical examination. Follow-up assessments occurred 9-12 months later, where the same data were collected. Fatigue was determined with the Fatigue Severity Scale (FSS), a score of ≥ 4 means moderate to high fatigue. The frequency and severity of other symptoms and the percentage of patients that meet the ME/CFS criteria were assessed using the DePaul Symptom Questionnaire-2 (DSQ-2). A self-organizing map was used to visualize the clustering of patients based on severity and frequency of 79 symptoms. In a previous study, 337 Dutch ME/CFS patients were clustered based on their symptom scores. The symptom scores of post COVID-19 patients were applied to these clusters to examine whether the same or different clusters were found. RESULTS: According to the FSS, fatigue was reported by 75.9% of the patients at 3-6 months after infection and by 57.1% of the patients 9-12 months later. Post-exertional malaise, sleep disturbances, pain, and neurocognitive symptoms were also frequently reported, according to the DSQ-2. Over half of the patients (52.7%) met the Fukuda criteria for ME/CFS, while fewer patients met other ME/CFS definitions. Clustering revealed specific symptom patterns and showed that post COVID-19 patients occurred in 11 of the clusters that have been observed in the ME/CFS cohort, where 2 clusters had > 10 patients. CONCLUSIONS: This study shows persistent fatigue and diverse symptomatology in post COVID-19 patients, up to 12-18 months after SARS-CoV-2 infection. Clustering showed that post COVID-19 patients occurred in 11 of the clusters that have been observed in the ME/CFS cohort.

A systematic review and meta-analysis of urinary biomarkers in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a multifactorial illness that affects many body systems including the immune, nervous, endocrine, cardiovascular, and urinary systems. There is currently no universal diagnostic marker or targeted treatment for ME/CFS. Urine is a non-invasive sample that provides biomarkers that may have the potential to be used in a diagnostic capacity for ME/CFS. While there are several studies investigating urine-based biomarkers for ME/CFS, there are no published systematic reviews to summarise existing evidence of these markers. The aim of this systematic review was to compile and appraise literature on urinary-based biomarkers in ME/CFS patients compared with healthy controls. METHODS: Three databases: Embase, PubMed, and Scopus were searched for articles pertaining to urinary biomarkers for ME/CFS compared with healthy controls published between December 1994 to December 2022. The final articles included in this review were determined through application of specific inclusion and exclusion criteria. Quality and bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Case Control Studies. A meta-analysis according to Cochrane guidelines was conducted on select studies, in particular, those that investigate urinary free cortisol levels in ME/CFS patients compared to healthy controls using the program STATA 17. RESULTS: Twenty-one studies were included in this review. All of the studies investigated urinary-based markers in ME/CFS patients compared with healthy controls. The reported changes in urinary outputs include urinary free cortisol (38.10%), carnitine (28.6%), iodine (4.76%), and the metabolome (42.86%). In most cases, there was minimal overlap in the main outcomes measured across the studies, however, differences in urinary free cortisol between ME/CFS patients and healthy controls were commonly reported. Seven studies investigating urinary free cortisol were included in the meta-analysis. While there were significant differences found in urinary free cortisol levels in ME/CFS patients, there was also substantial heterogeneity across the included studies that makes drawing conclusions difficult. CONCLUSIONS: There is limited evidence suggesting a consistent and specific potential urinary-based biomarker for ME/CFS. Further investigations using more standardised methodologies and more stringent case criteria may be able to identify pathophysiological differences with diagnostic potential in ME/CFS patients compared with healthy controls.

Increased risk of chronic fatigue syndrome following infection: a 17-year population-based cohort study.

BACKGROUND: Previous serological studies have indicated an association between viruses and atypical pathogens and Chronic Fatigue Syndrome (CFS). This study aims to investigate the correlation between infections from common pathogens, including typical bacteria, and the subsequent risk of developing CFS. The analysis is based on data from Taiwan's National Health Insurance Research Database. METHODS: From 2000 to 2017, we included a total of 395,811 cases aged 20 years or older newly diagnosed with infection. The cases were matched 1:1 with controls using a propensity score and were followed up until diagnoses of CFS were made. RESULTS: The Cox proportional hazards regression analysis was used to estimate the relationship between infection and the subsequent risk of CFS. The incidence density rates among non-infection and infection population were 3.67 and 5.40 per 1000 person-years, respectively (adjusted hazard ratio [HR] = 1.5, with a 95% confidence interval [CI] 1.47-1.54). Patients infected with Varicella-zoster virus, Mycobacterium tuberculosis, Escherichia coli, Candida, Salmonella, Staphylococcus aureus and influenza virus had a significantly higher risk of CFS than those without these pathogens (p < 0.05). Patients taking doxycycline, azithromycin, moxifloxacin, levofloxacin, or ciprofloxacin had a significantly lower risk of CFS than patients in the corresponding control group (p < 0.05). CONCLUSION: Our population-based retrospective cohort study found that infection with common pathogens, including bacteria, viruses, is associated with an increased risk of developing CFS.

Presence of depression and anxiety with distinct patterns of pharmacological treatments before the diagnosis of chronic fatigue syndrome: a population-based study in Taiwan.

OBJECTIVE: An increased prevalence of psychiatric comorbidities (including depression and anxiety disorder) has been observed among patients with chronic fatigue syndrome (CFS). However, few studies have examined the presence of depression and anxiety disorder before the diagnosis of CFS. This study aimed to clarify the preexisting comorbidities and treatments associated with patients with subsequent CFS diagnosis in a population-based cohort in Taiwan. METHODS: An analysis utilizing the National Health Insurance Research Database of Taiwan was conducted. Participants included were 6303 patients with CFS newly diagnosed between 2000 and 2010 and 6303 age-/sex-matched controls. RESULTS: Compared with the control group, the CFS group had a higher prevalence of depression and anxiety disorder before the diagnosis of CFS. Sampled patients who took specific types of antidepressants, namely, selective serotonin reuptake inhibitors (adjusted odds ratio [aOR] = 1.21, 95% confidence interval [CI] 1.04-1.39), serotonin antagonists and reuptake inhibitors (SARI; aOR = 1.87, 95% CI 1.59-2.19), and tricyclic antidepressants (aOR = 1.46, 95% CI 1.09-1.95), had an increased risk of CFS. CFS risk was also higher among participants taking benzodiazepine, muscle relaxants, and analgesic drugs. A sub-group analysis revealed that SARI use was related to an increased risk of CFS in the depression, anxiety disorder, male, and female groups. In the depression and anxiety disorder groups, analgesic drug use was associated with an increased CFS risk. Nonpharmacological treatment administration differed between men and women. CONCLUSION: This population-based retrospective cohort study revealed an increased risk of CFS among populations with preexisting depression and anxiety disorder, especially those taking SARI and analgesic drugs.

Role of selective attention in fatigue in neurological disorders.

BACKGROUND: Chronic fatigue is a significant symptom in several diseases including traumatic and degenerative neurological disorders. While several studies have investigated the correlates of chronic fatigue, there is as yet no unifying framework to explain chronic fatigue. METHODS: In this narrative review, I investigate the role of selective attention in the development of chronic fatigue and discuss results within the framework of the sensory attenuation model of fatigue, which posits that fatigue is the phenomenological output of altered attention to sensory input. Following a short introduction of this framework, I present results from investigations that address attentional mechanisms in fatigue in multiple sclerosis, stroke, traumatic brain injury and Parkinson's disease. RESULTS: Attention was quantified in all four disease models using a variety of outcome measures, including behavioural, neurophysiological, structural and functional brain connectivity. The range of measures precluded direct comparison of results across disease conditions; however, in all four disease models there was evidence of poor selective attention that explained levels of chronic fatigue, supporting the sensory attenuation model of fatigue as a disease-independent mechanism of fatigue. Evidence was lacking to draw any conclusions about the direction of causality. CONCLUSION: The role of selective attention in development of fatigue is indicated. Future studies must focus on establishing causality and exploring attentional circuitry as a potential therapeutic target.

Coping strategies in patients with good outcome but chronic fatigue after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Fatigue is a highly prevalent and debilitating symptom among patients in the chronic phase of aneurysmal subarachnoid haemorrhage (aSAH) with no identified effective treatment. Cognitive therapy has been shown to have moderate effects on fatigue. Delineating the coping strategies used by patients with post-aSAH fatigue and relating them to fatigue severity and emotional symptoms could be a step towards developing a behavioural therapy for post-aSAH fatigue. METHODS: Ninety-six good outcome patients with chronic post-aSAH fatigue answered the questionnaires Brief COPE, (a questionnaire defining 14 coping strategies and three Coping Styles), the Fatigue Severity Scale (FSS), Mental Fatigue Scale (MFS), Beck Depression Inventory (BDI-II) and Beck Anxiety Inventory (BAI). The Brief COPE scores were compared with fatigue severity and emotional symptoms of the patients. RESULTS: The prevailing coping strategies were "Acceptance", "Emotional Support", "Active Coping" and "Planning". "Acceptance" was the sole coping strategy that was significantly inversely related to levels of fatigue. Patients with the highest scores for mental fatigue and those with clinically significant emotional symptoms applied significantly more maladaptive avoidant strategies. Females and the youngest patients applied more "Problem-Focused" strategies. CONCLUSION: A therapeutic behavioural model aiming at furthering "Acceptance" and reducing passivity and "Avoidant" strategies may contribute to alleviate post-aSAH fatigue in good outcome patients. Given the chronic nature of post-aSAH fatigue, neurosurgeons may encourage patients to accept their new situation so that they can start a process of positive reframing instead of being trapped in a spiral of futile loss of energy and secondary increased emotional burden and frustration.

Incidence and contributing factors of non-root canal treated teeth with chronic fatigue root fracture: A cross-sectional study.

BACKGROUND/PURPOSE: Chronic fatigue root fracture describes a root fracture in a non-root canal treated (non-RCT) tooth. This study aimed to report the incidence and contributing factors of non-RCT teeth with chronic fatigue root fracture in a Taiwanese population. METHODS: This cross-sectional study included teeth extracted at Taipei Veterans General Hospital in Taiwan between 2018 and 2019. The reasons for extractions were recorded and included vertical and horizontal root fractures (VRF and HRF). Comparisons of clinical factors between teeth with fatigue VRF and teeth with fatigue HRF were performed by chi-square or Fisher exact test, where appropriate. RESULTS: Of the 4207 extracted teeth examined, 263 (6.25%) had tooth fracture. Thirty-two non-RCT teeth had chronic fatigue root fracture, including 16 with VRF and 16 with HRF. The incidence was 0.76% (32/4207). The occurrence of chronic fatigue root fracture was higher in males (83.9%). The mean age of the 31 patients with chronic fatigue root fracture was 71.7 ± 13.1 years. More than half of these teeth had intact crowns with severe attrition. The fatigue VRF occurred more frequently in molars (P = 0.003), in roots with a long oval cross-section (P = 0.037), and in terminal teeth (P = 0.013) than the fatigue HRF. CONCLUSION: The incidence of chronic fatigue root fracture is 0.76%. Both VRF and HRF occur mainly in aged males, in posterior teeth with attrition, and in teeth without restoration. Tooth position, cross-section root morphology, and terminal tooth are contributing factors related to chronic fatigue root fracture.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Comorbidities: Linked by Vascular Pathomechanisms and Vasoactive Mediators?

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is often associated with various other syndromes or conditions including mast cell activation (MCA), dysmenorrhea and endometriosis, postural tachycardia (POTS) and small fiber neuropathy (SFN). The causes of these syndromes and the reason for their frequent association are not yet fully understood. We previously published a comprehensive hypothesis of the ME/CFS pathophysiology that explains the majority of symptoms, findings and chronicity of the disease. We wondered whether some of the identified key pathomechanisms in ME/CFS are also operative in MCA, endometriosis and dysmenorrhea, POTS, decreased cerebral blood flow and SFN, and possibly may provide clues on their causes and frequent co-occurrence. Our analysis indeed provides strong arguments in favor of this assumption, and we conclude that the main pathomechanisms responsible for this association are excessive generation and spillover into the systemic circulation of inflammatory and vasoactive tissue mediators, dysfunctional ß2AdR, and the mutual triggering of symptomatology and disease initiation. Overall, vascular dysfunction appears to be a strong common denominator in these linkages.

Brain fog of post-COVID-19 condition and Chronic Fatigue Syndrome, same medical disorder?

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is characterized by persistent physical and mental fatigue. The post-COVID-19 condition patients refer physical fatigue and cognitive impairment sequelae. Given the similarity between both conditions, could it be the same pathology with a different precipitating factor? OBJECTIVE: To describe the cognitive impairment, neuropsychiatric symptoms, and general symptomatology in both groups, to find out if it is the same pathology. As well as verify if the affectation of smell is related to cognitive deterioration in patients with post-COVID-19 condition. METHODS: The sample included 42 ME/CFS and 73 post-COVID-19 condition patients. Fatigue, sleep quality, anxiety and depressive symptoms, the frequency and severity of different symptoms, olfactory function and a wide range of cognitive domains were evaluated. RESULTS: Both syndromes are characterized by excessive physical fatigue, sleep problems and myalgia. Sustained attention and processing speed were impaired in 83.3% and 52.4% of ME/CFS patients while in post-COVID-19 condition were impaired in 56.2% and 41.4% of patients, respectively. Statistically significant differences were found in sustained attention and visuospatial ability, being the ME/CFS group who presented the worst performance. Physical problems and mood issues were the main variables correlating with cognitive performance in post-COVID-19 patients, while in ME/CFS it was anxiety symptoms and physical fatigue. CONCLUSIONS: The symptomatology and cognitive patterns were similar in both groups, with greater impairment in ME/CFS. This disease is characterized by greater physical and neuropsychiatric problems compared to post-COVID-19 condition. Likewise, we also propose the relevance of prolonged hyposmia as a possible marker of cognitive deterioration in patients with post-COVID-19.

How mycobacterium tuberculosis infection could lead to the increasing risks of chronic fatigue syndrome and the potential immunological effects: a population-based retrospective cohort study.

BACKGROUND: Chronic fatigue syndrome (CFS) has been shown to be associated with infections. Tuberculosis (TB) is a highly prevalent infectious disease. Patients with chronic fatigue syndrome and post-tuberculosis experience similar symptoms. Furthermore, chronic fatigue syndrome and tuberculosis share similar plasma immunosignatures. This study aimed to clarify the risk of chronic fatigue syndrome following the diagnosis of Mycobacterium tuberculosis infection (MTI), by analyzing the National Health Insurance Research Database of Taiwan. METHODS: 7666 patients aged 20 years or older with newly diagnosed Mycobacterium tuberculosis infection during 2000-2011 and 30,663 participants without Mycobacterium tuberculosis infection were identified. Both groups were followed up until the diagnoses of chronic fatigue syndrome were made at the end of 2011. RESULTS: The relationship between Mycobacterium tuberculosis infection and the subsequent risk of chronic fatigue syndrome was estimated through Cox proportional hazards regression analysis, with the incidence density rates being 3.04 and 3.69 per 1000 person-years among the non-Mycobacterium tuberculosis infection and Mycobacterium tuberculosis infection populations, respectively (adjusted hazard ratio [HR] = 1.23, with 95% confidence interval [CI] 1.03-1.47). In the stratified analysis, the Mycobacterium tuberculosis infection group were consistently associated with a higher risk of chronic fatigue syndrome in the male sex (HR = 1.27, 95% CI 1.02-1.58) and age group of ≥ 65 years old (HR = 2.50, 95% CI 1.86-3.38). CONCLUSIONS: The data from this population-based retrospective cohort study revealed that Mycobacterium tuberculosis infection is associated with an elevated risk of subsequent chronic fatigue syndrome.

Oxaloacetate Treatment For Mental And Physical Fatigue In Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long-COVID fatigue patients: a non-randomized controlled clinical trial.

BACKGROUND: There is no approved pharmaceutical intervention for Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS). Fatigue in these patients can last for decades. Long COVID may continue to ME/CFS, and currently, it is estimated that up to 20 million Americans have significant symptoms after COVID, and the most common symptom is fatigue. Anhydrous Enol-Oxaloacetate, (AEO) a nutritional supplement, has been anecdotally reported to relieve physical and mental fatigue and is dimished in ME/CFS patients. Here, we examine the use of higher dosage AEO as a medical food to relieve pathological fatigue. METHODS: ME/CFS and Long-COVID patients were enrolled in an open label dose escalating "Proof of Concept" non-randomized controlled clinical trial with 500 mg AEO capsules. Control was provided by a historical ME/CFS fatigue trial and supporting meta-analysis study, which showed average improvement with oral placebo using the Chalder Scale of 5.9% improvement from baseline. At baseline, 73.7% of the ME/CFS patients were women, average age was 47 and length of ME/CFS from diagnosis was 8.9 years. The Long-COVID patients were a random group that responded to social media advertising (Face Book) with symptoms for at least 6 months. ME/CFS patients were given separate doses of 500 mg BID (N = 23), 1,000 mg BID (N = 29) and 1000 mg TID (N = 24) AEO for six weeks. Long COVID patients were given 500 mg AEO BID (N = 22) and 1000 mg AEO (N = 21), again over a six-week period. The main outcome measure was to compare baseline scoring with results at 6 weeks with the Chalder Fatigue Score (Likert Scoring) versus historical placebo. The hypothesis being tested was formulated prior to data collection. RESULTS: 76 ME/CFS patients (73.7% women, median age of 47) showed an average reduction in fatigue at 6 weeks as measured by the "Chalder Fatigue Questionnaire" of 22.5% to 27.9% from baseline (P < 0.005) (Likert scoring). Both physical and mental fatigue were significantly improved over baseline and historical placebo. Fatigue amelioration in ME/CFS patients increased in a dose dependent manner from 21.7% for 500 mg BID to 27.6% for 1000 mg Oxaloacetate BID to 33.3% for 1000 mg TID. Long COVID patients' fatigue was significantly reduced by up to 46.8% in 6-weeks. CONCLUSIONS: Significant reductions in physical and metal fatigue for ME/CFS and Long-COVID patients were seen after 6 weeks of treatment. As there has been little progress in providing fatigue relief for the millions of ME/CFS and Long COVID patients, anhydrous enol oxaloacetate may bridge this important medical need. Further study of oxaloacetate supplementation for the treatment of ME/CFS and Long COVID is warranted. Trial Registration https://clinicaltrials.gov/ct2/show/NCT04592354 Registered October 19, 2020. 1,000 mg BID Normalized Fatigue Data for Baseline, 2-weeks and 6-weeks evaluated by 3 Validated Fatigue Scoring Questionnaires.

The Presentation of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Influenced by the Presence or Absence of Joint Hypermobility.

OBJECTIVE: To examine demographic and clinical characteristics of individuals with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) with and without joint hypermobility We hypothesized that patients who were joint hypermobility-positive would have an earlier onset of ME/CFS symptoms as well as increased severity, a greater number of comorbid conditions, and a lower health-related quality of life. STUDY DESIGN: From an observational cohort study of 55 individuals meeting the Fukuda criteria for ME/CFS, we compared groups using a Beighton score cutoff of 4 or higher to indicate joint hypermobility. Chart data were collected to examine the age and type of onset of ME/CFS and the presence of comorbid conditions. The impact on quality of life was assessed through questionnaires that included the Peds QL, Functional Disability Inventory, Peds QL Multidimensional Fatigue Scale, and Anxiety Subscale of the Symptom Checklist 90. RESULTS: There was no significant difference between groups in mean ± SD age at onset of ME/CFS (13.3 ± 3.3 years vs 13.3 ± 2.3 years; P = .92), sex, frequency, and severity of ME/CFS symptoms, orthostatic intolerance symptoms, or comorbid conditions. There was no significant difference between the groups in measures of health-related quality of life using a Beighton score cutoff of 4 or a cutoff of 5 to define joint hypermobility. CONCLUSIONS: Despite being a risk factor for the development of ME/CFS, joint hypermobility as defined in this study was not associated with other clinical characteristics of the illness.

Performance Validity and Outcome of Cognitive Behavior Therapy in Patients with Chronic Fatigue Syndrome.

OBJECTIVE: There is limited research examining the impact of the validity of cognitive test performance on treatment outcome. All known studies to date have operationalized performance validity dichotomously, leading to the loss of predictive information. Using the range of scores on a performance validity test (PVT), we hypothesized that lower performance at baseline was related to a worse treatment outcome following cognitive behavioral therapy (CBT) in patients with Chronic Fatigue Syndrome (CFS) and to lower adherence to treatment. METHOD: Archival data of 1081 outpatients treated with CBT for CFS were used in this study. At baseline, all patients were assessed with a PVT, the Amsterdam Short-Term Memory test (ASTM). Questionnaires assessing fatigue, physical disabilities, psychological distress, and level of functional impairment were administered before and after CBT. RESULTS: Our main hypothesis was not confirmed: the total ASTM score was not significantly associated with outcomes at follow-up. However, patients with a missing follow-up assessment had a lower ASTM performance at baseline, reported higher levels of physical limitations, and completed fewer therapy sessions. CONCLUSIONS: CFS patients who scored low on the ASTM during baseline assessment are more likely to complete fewer therapy sessions and not to complete follow-up assessment, indicative of limited adherence to treatment. However, if these patients were retained in the intervention, their response to CBT for CFS was comparable with subjects who score high on the ASTM. This finding calls for more research to better understand the impact of performance validity on engagement with treatment and outcomes.

Chronic fatigue syndrome and cognitive deficit are associated with acute-phase neuropsychiatric manifestations of COVID-19: A 9-month follow-up study.

The preva lence of long-COVID symptoms is rising but it is not still possible to predict which patients will present them, and which types of symptoms they will present. We followed up 95 patients with confirmed COVID-19 for 9 months to identify and characterize long-COVID symptoms. Easy fatigability was the most common symptom (51.04%), followed by anxiety (38.54%), dyspnea (38.54%), and new-onset headache (38.54%). There was no association between COVID-19 severity in the acute phase and the number of long-COVID symptoms (F(1,93) = 0.75, p = 0.45), and cognitive function (MoCA) scores (F(1,90) = 0.073, p = 0.787) at follow-up. Being female (F(1,92) = - 2.27, p = 0.02), having a higher number of symptoms (F(1,93) = 2.76, p = 0.0068), and experiencing constitutional neuropsychiatric symptoms (F(1,93) = 2.529, p = 0.01) in the acute phase were associated with having chronic fatigue syndrome at follow-up. Moreover, constitutional neuropsychiatric symptoms in the acute phase were associated with a lower MoCA score (F(1,93) = 10.84, p = 0.001) at follow-up. Specific clinical presentations such as constitutional neuropsychiatric symptoms in the acute phase might be predictors of debilitating long-COVID symptoms such as chronic fatigue syndrome and cognitive deficits.

Clinical Characteristics of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Diagnosed in Patients with Long COVID.

Background and Objectives: COVID-19 can be serious not only in the acute phase but also after the acute phase and some patients develop ME/CFS. There have been few studies on patients with long COVID in whom ME/CFS was diagnosed by physicians based on standardized criteria after examinations and exclusion diagnosis and not based on only subjective symptoms. The purpose of this study was to elucidate the detailed characteristics of ME/CFS in patients with long COVID. Materials and Methods: A retrospective descriptive study was performed for patients who visited a COVID-19 aftercare clinic established in Okayama University Hospital during the period was from February 2021 to April 2022. Results: Clinical data were obtained from medical records for 281 patients, and 279 patients who met the definition of long COVID were included. The overall prevalence rate of ME/CFS diagnosed by three sets of ME/CFS criteria (Fukuda, Canadian and IOM criteria) was 16.8% (48.9% in male and 51.1% in females). The most frequent symptoms in ME/CFS patients were general fatigue and post-exertional malaise (89.4% of the patients), headache (34.0%), insomnia (23.4%), dysosmia (21.3%) and dysgeusia (19.1%). Dizziness, chest pain, insomnia and headache were characteristic symptoms related to ME/CFS. The male to female ratio in ME/CFS patients was equal in the present study, although ME/CFS was generally more common in women in previous studies. Given that patients with ME/CFS had more severe conditions in the acute phase of COVID-19, the severity of the acute infectious state might be involved in the pathophysiology of ME/CFS. Conclusions: The prevalence rate of ME/CFS and the characteristic sequelae in the long COVID condition were revealed in this study.

Nationwide epidemiological characteristics of chronic fatigue syndrome in South Korea.

BACKGROUND: Chronic fatigue syndrome (CFS) is a long-term disabling illness accompanied by medically unexplained fatigue. This study aimed to explore the epidemiological characteristics of CFS in South Korea. METHODS: Using the nationwide medical records provided by the Korean Health Insurance Review & Assessment Service (HIRA), we analyzed the entire dataset for CFS patients diagnosed by physicians in South Korea from January 2010 to December 2020. RESULTS: The annual mean incidence of CFS was estimated to be 44.71 ± 6.10 cases per 100,000 individuals [95% CI: 40.57, 48.76], and the prevalence rate was 57.70 ± 12.20 cases per 100,000 individuals [95% CI: 49.40, 65.79]. These two rates increased by 1.53- and 1.94-fold from 2010 to 2020, respectively, and showed an increasing trend with aging and an approximately 1.5-fold female predominance. CONCLUSIONS: This study is the first to report the nationwide epidemiological features of CFS, which reflects the clinical reality of CFS diagnosis and care in South Korea. This study will be a valuable reference for studies of CFS in the future.

Prevalence and correlates of chronic fatigue syndrome and post-traumatic stress disorder after the outbreak of the COVID-19.

As the SARS-COV-2 becomes a global pandemic, many researchers have a concern about the long COVID-19 complications. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a persistent, debilitating, and unexplained fatigue disorder. We investigated psychological morbidities such as CFS and post-traumatic stress disorder (PTSD) among survivors of COVID-19 over 6 months. All COVID-19 survivors from the university-affiliated hospital of Tehran, Iran, were assessed 6 months after infection onset by a previously validated questionnaire based on the Fukuda guidelines for CFS/EM and DSM-5 Checklist for PTSD (The Post-traumatic Stress Disorder Checklist for DSM-5 or PCL-5) to determine the presence of stress disorder and chronic fatigue problems. A total of 120 patients were enrolled. The prevalence rate of fatigue symptoms was 17.5%. Twelve (10%) screened positive for chronic idiopathic fatigue (CIF), 6 (5%) for CFS-like with insufficient fatigue syndrome (CFSWIFS), and 3 (2.5%) for CFS. The mean total scores in PCL-5 were 9.27 ± 10.76 (range:0-44), and the prevalence rate of PTSD was 5.8%. There was no significant association after adjusting between CFS and PTSD, gender, comorbidities, and chloroquine phosphate administration. The obtained data revealed the prevalence of CFS among patients with COVID-19, which is almost similar to CFS prevalence in the general population. Moreover, PTSD in patients with COVID-19 is not associated with the increased risk of CFS. Our study suggested that medical institutions should pay attention to the psychological consequences of the COVID-19 outbreak.

[Influence of successful psychopharmacotherapy of anxiety-depressive spectrum disorders on the severity of chronic fatigue in patients with rheumatoid arthritis].

AIM: To assess the influence of psychopharmacotherapy (PPT) of anxiety and depressive disorders on fatigue severity in patients with rheumatoid arthritis (RA). MATERIALS AND METHODS: 128 RA-patients were included. Severity of fatigue was measured with fatigue severity scale (FSS), clinically important fatigue was diagnosed in patients with FSS4. Anxiety and depressive disorders (ADD) were diagnosed by a licensed psychiatrist in 123 (96.1%) of RA-patients in accordance with ICD-10 in semi-structured interview. Severity of depression and anxiety was evaluated with MontgomeryAsberg Depression Rating Scale (MADRS) and Hamilton Anxiety Rating Scale (HAM-A). RA-patients with ADD were divided into the following treatment groups: 1 сDMARDs (n=39), 2 сDMARDs+PPT (sertraline or mianserine), n=43, 3 сDMARDs+bDMARDs (n=32), 4 сDMARDs+bDMARDs+PPT (sertraline or mianserine), n=9. Biologics treatment duration varied from 1 to 5 years, antidepressants from 6 to 96 weeks. 83 (67.5%) RA patients were assessed at five-years follow-up. Multinominal logistic regression analysis was conducted to determine factors associated with clinically important fatigue. RESULTS: Multinominal logistic regression analysis showed clinically important fatigue at baseline to be positively associated (OR 13.57; 95% CI 3.04460.486; p=0.01) and remission of ADD negatively associated (OR 0.162; 95% CI 0.0320.809; p=0.027), with clinically important fatigue at 5 years follow-up (R2=0.385, p0.0001). CONCLUSION: Due to significant relationship between mental health status, antidepressants treatment and clinically important fatigue in RA-patients, all patients reporting clinically important fatigue should be recommended mental health counselling by a licensed psychiatrist.

Reduced heart rate variability predicts fatigue severity in individuals with chronic fatigue syndrome/myalgic encephalomyelitis.

BACKGROUND: Heart rate variability (HRV) is an objective, non-invasive tool to assessing autonomic dysfunction in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). People with CFS/ME tend to have lower HRV; however, in the literature there are only a few previous studies (most of them inconclusive) on their association with illness-related complaints. To address this issue, we assessed the value of different diurnal HRV parameters as potential biomarker in CFS/ME and also investigated the relationship between these HRV indices and self-reported symptoms in individuals with CFS/ME. METHODS: In this case-control study, 45 female patients who met the 1994 CDC/Fukuda definition for CFS/ME and 25 age- and gender-matched healthy controls underwent HRV recording-resting state tests. The intervals between consecutive heartbeats (RR) were continuously recorded over three 5-min periods. Time- and frequency-domain analyses were applied to estimate HRV variables. Demographic and clinical features, and self-reported symptom measures were also recorded. RESULTS: CFS/ME patients showed significantly higher scores in all symptom questionnaires (p < 0.001), decreased RR intervals (p < 0.01), and decreased HRV time- and frequency-domain parameters (p < 0.005), except for the LF/HF ratio than in the healthy controls. Overall, the correlation analysis reached significant associations between the questionnaires scores and HRV time- and frequency-domain measurements (p < 0.05). Furthermore, separate linear regression analyses showed significant relationships between self-reported fatigue symptoms and mean RR (p = 0.005), RMSSD (p = 0.0268) and HFnu indices (p = 0.0067) in CFS/ME patients, but not in healthy controls. CONCLUSIONS: Our findings suggest that ANS dysfunction presenting as increased sympathetic hyperactivity may contribute to fatigue severity in individuals with ME/CFS. Further studies comparing short- and long-term HRV recording and self-reported outcome measures with previous studies in larger CFS/ME cohorts are urgently warranted.

Attentional Processing and Interpretative Bias in Functional Neurological Disorder.

OBJECTIVE: Altered attentional processing (automatically attending to negative or illness-relevant information) and interpretative biases (interpreting ambiguous information as negative or illness relevant) may be mechanistically involved in functional neurological disorder (FND). Common mechanisms between FND and chronic fatigue syndrome (CFS) have been proposed but not compared experimentally. METHODS: We compared the cognitive task performance of FND, CFS, and healthy control (HC) groups. The tasks assessed attentional bias toward illness-relevant stimuli (visual probe task), attentional control (attention network task), and somatic interpretations (interpretative bias task), alongside self-reported depression, anxiety, fatigue, and general health. RESULTS: Thirty-seven participants diagnosed with FND, 52 participants diagnosed with CFS, and 51 HC participants were included. Although participants with CFS showed attentional bias for illness-relevant stimuli relative to HC (t = -3.13, p = .002, d = 0.624), individuals with FND did not (t = -1.59, p = .118, d = 0.379). Both the FND (t = 3.08, p = .003, d = 0.759) and CFS (t = 2.74, p = .007, d = 0.548) groups displayed worse attentional control than did the HC group. Similarly, the FND (t = 3.63, p < .001, d = 0.801) and CFS groups (t = 4.58, p < .001, d = 0.909) showed more somatic interpretative bias than did the HC group. CONCLUSIONS: Similar attentional control deficits and somatic interpretative bias in individuals with FND and CFS support potential shared mechanisms underlying symptoms. Interpretative bias toward somatic and illness-relevant stimuli in functional disorders may prove a therapeutic target.