Tag: long covid symptoms

Long-COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): Potential neurophysiological biomarkers for these enigmatic entities

Since early in the pandemic, fatigue has been recognized as one of the most common persistent complaints in individuals infected with SARS-CoV-2, and constitutes one main symptom of the so-called long-COVID syndrome. The term fatigue refers to a sustained feeling of tiredness, which can be present at rest; it is not directly related to physical activity, but can be exacerbated disproportionally by exertion.

Survivors of other recent coronavirus outbreaks, such as severe acute respiratory syndrome (SARS) in 2002 and Middle East respiratory syndrome (MERS) in 2012 also developed chronic fatigue. These ‘post-infectious’ fatigue syndromes, including long-COVID, resemble myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a chronic disorder of unknown physiopathology characterized by fatigue, post-exertional malaise, chronic muscle or skeletal pain, and cognitive impairment (‘brain fog’).

Despite it being an extremely disabling symptom, the results of routine examinations are often normal in patients complaining of lingering fatigue, a phenomenon that has also led the medical-scientific community to view this condition with skepticism.

In physiology, fatigue is defined as a decrease in the maximal force-generating capacity of a muscle during exercise. It may result from peripheral processes distal to the neuromuscular junction and from central processes controlling the discharge rate of motoneurons.

Physical fatigue related to both central and peripheral nervous system dysfunction can be assessed with neurophysiological techniques including transcranial magnetic stimulation (TMS) of the motor cortex, electrical stimulation of nerve trunks or intramuscular nerve fibers, and electromyography (EMG) recordings.

In August 2021, the first study showing myopathic changes in quantitative EMG (qEMG) in long-COVID patients with musculoskeletal symptoms was published (). The same authors demonstrated myopathic qEMG features and histopathological changes in skeletal muscle biopsies in 16 patients with complaints of fatigue, myalgia, and/or weakness persisting for up to 14 months after mild to moderate COVID-19 (). The wide variety of histological changes in this study, including muscle fiber atrophy, mitochondrial changes, subsarcolemmal accumulation, inflammation, capillaries alteration, suggests that skeletal muscle may be a major target of SARS-CoV-2.

On the opposite side of the neuroaxis, dysfunction in the activity of the primary motor cortex and reduced corticomotor output may underlie fatigue.

The first TMS study on motor cortex physiology was conducted on 12 patients with long-term fatigue and ‘brain fog’ after severe COVID-19 (). It showed disruption of the physiological mechanism of post-contraction depression, i.e., the transient decrease in the amplitude of motor evoked potentials and prolongation of the cortical silent period after a fatiguing motor task, which depends on cortical inhibitory mechanisms and has the protective purpose of preventing muscle overload. Impairment of intracortical GABAergic activity, as indicated by disrupted long-interval intracortical inhibition, together with reduced excitability of the primary motor cortex was subsequently demonstrated in 67 patients with fatigue and cognitive difficulties after mild COVID-19 (). These patients also presented selective deficits in executive functions. Based on these findings, the authors proposed that fatigue depends on altered excitability and neurotransmission within the motor cortex at rest, and on abnormal reactivity to muscular exercise. In addition, reduced executive control may contribute to exacerbating poor physical performance and fatigue tolerance ().

These objective neurophysiological and histopathological findings showed for the first time that fatigue may due both to pathological processes in the muscle (the effector of the motor command) and/or at the site of motor command processing. The mechanisms of chronic dysfunction of neural and muscle cells may be sustained by inflammation or dysimmunity, triggered by SARS-COV-2 in predisposed individuals.

Immune-inflammatory and neuroendocrine mechanisms have also been implicated in ME/CFS. In particular, increased production of autoantibodies against CNS and autonomic nervous system targets, such as the ß2 adrenergic receptor (ß2AdR), have been documented (). As ß2AdR are important vasodilators, their functional disturbance may result in vasoconstriction and hypoxemia with chronic muscular and cerebral hypoperfusion.

The COVID-19 pandemic is likely to greatly increase the incidence of ME/CFS, so that the intense research on the pathophysiological mechanisms of fatigue in long-COVID can help to shed light on a poorly understood and underestimated syndrome.

Source: Versace V, Tankisi H. Long-COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): Potential neurophysiological biomarkers for these enigmatic entities. Clin Neurophysiol. 2023 Jan 13;147:58-59. doi: 10.1016/j.clinph.2023.01.001. Epub ahead of print. PMID: 36657309; PMCID: PMC9838078. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9838078/ (Full text)

Epidemiology, symptomatology, and risk factors for long COVID symptoms: Multi-centre study

Abstract:

Background: Long COVID induces a substantial global burden of disease. The pathogenesis, complications, epidemiological and clinical characteristics of COVID-19 patients in the acute phase have been evaluated, while few studies have characterized the epidemiology, symptomatology and risk factors of long COVID symptoms. Its characteristics among coronavirus disease 2019 (COVID-19) patients in the general population remain unaddressed.

Objective: We examined the prevalence of long COVID symptoms, its symptom patterns, and its risk factors. we aimed to fill the knowledge gaps by evaluating the prevalence of long COVID symptoms in four major Chinese cities.

Methods: We performed a population-based, multi-centre survey by a representative sampling strategy via the Qualtrics platform in Beijing, Shanghai, Guangzhou and Hong Kong (June 2022). We included 2,712 community-dwelling, COVID-19 patients, and measured the prevalence of long COVID symptoms defined by the WHO, and their risk factors. The primary outcomes were the symptoms of long COVID with various levels of impact. A descriptive analysis was conducted on the prevalence and distribution of the long COVID symptoms according to disease severity. A sensitivity analysis of increasing the number of long COVID symptoms was also conducted. A univariate and multivariate regression analysis was performed to examine the risk factors of severe long COVID symptoms, including age, gender, marital status, current occupation, educational level, living status, smoking habits, monthly household income, self-perceived health status, presence of chronic diseases, use of chronic medication, COVID-19 vaccination status, and severity of COVID-19.

Results: The response rate was 63.6%. The prevalence of long COVID, moderate or severe long COVID, and severe long COVID was 90.4%, 62.4%, and 31.0%, respectively. Fatigue (33.7%), cough (31.9%), sore throat (31.0%), difficulty in concentration (30.5%), feeling of anxiety (30.2%), myalgia (29.9%), and arthralgia (29.9%) were the most common severe long COVID symptoms. From multivariate regression analysis, female gender (adjusted odds ratio [aOR]=1.49, 95% C.I.=1.13-1.95), engagement in transportation, logistics, or discipline workforce (aOR=2.52, 95% C.I.=1.58-4.03), living with domestic workers (aOR=2.37, 95% C.I.=1.39-4.03), smoking (aOR=1.55, 95% C.I.=1.17-2.05), poor self-perceived health status (aOR 5.06 to 15.38), chronic diseases (aOR 1.92 to 2.71), chronic medication use (aOR=4.38, 95% C.I.=1.66-11.53), and critical severity of COVID-19 (aOR=1.52, 95% C.I.=1.07-2.15) were associated with severe long COVID. Prior vaccination for ≥2 doses of COVID-19 was a protective factor (aOR=0.35-0.22, 95% C.I.=0.08-0.90).

Conclusions: We have examined the prevalence of long COVID symptoms in four Chinese cities according to the severity of COVID-19. We also evaluated the pattern of long COVID symptoms, and their risk factors. These findings may inform early identification of COVID-19 patients at risk of long COVID and planning of rehabilitative services.

Source: Wong MC, Huang J, Wong NY, Wong GL, Yip TC, Chan RN, Chau SW, Ng SC, Wing YK, Chan FK. Epidemiology, symptomatology, and risk factors for long COVID symptoms: Multi-centre study. JMIR Public Health Surveill. 2023 Jan 12. doi: 10.2196/42315. Epub ahead of print. PMID: 36645453. https://pubmed.ncbi.nlm.nih.gov/36645453/

Long COVID Symptomatology and Associated Factors in Primary Care Patients: The EPICOVID-AP21 Study

Abstract:

Persistent COVID-19 condition includes a wide variety of symptoms and health problems of indeterminate duration. The present study examined the sociodemographic and clinical characteristics of the population with Long COVID seen in Primary Care using a questionnaire based on the existing scientific literature. It was an observational and descriptive study of the characteristics of the Spanish population with Long COVID over 14 years of age.
The responses were analysed by means of a descriptive analysis of the variables recorded, in addition to a bivariate analysis to determine the existence of a relationship between persistent COVID-19 and variables such as gender, age, vaccination status or concomitant pathology. The results obtained clearly describe the sociodemographic characteristics of the population, highlighting the predominance of female gender and the prevalence of tiredness and fatigue.
Furthermore, relevant information was obtained on the differences in symptomatology according to gender, age, previous pathologies and alterations derived from infection and/or vaccination. These data are important for better detection, diagnosis and treatment of Long COVID and the improvement of the quality of life of this population.
Source: Romero-Rodríguez E, Perula-de-Torres LÁ, González-Lama J, Castro-Jiménez RÁ, Jiménez-García C, Priego-Pérez C, Vélez-Santamaría R, Simón-Vicente L, González-Santos J, González-Bernal JJ. Long COVID Symptomatology and Associated Factors in Primary Care Patients: The EPICOVID-AP21 Study. Healthcare. 2023; 11(2):218. https://doi.org/10.3390/healthcare11020218 https://www.mdpi.com/2227-9032/11/2/218 (Full text)

Long covid outcomes at one year after mild SARS-CoV-2 infection: nationwide cohort study

Abstract:

Objectives: To determine the clinical sequelae of long covid for a year after infection in patients with mild disease and to evaluate its association with age, sex, SARS-CoV-2 variants, and vaccination status.

Design: Retrospective nationwide cohort study.

Setting: Electronic medical records from an Israeli nationwide healthcare organisation.

Population: 1 913 234 Maccabi Healthcare Services members of all ages who did a polymerase chain reaction test for SARS-CoV-2 between 1 March 2020 and 1 October 2021.

Main outcome measures: Risk of an evidence based list of 70 reported long covid outcomes in unvaccinated patients infected with SARS-CoV-2 matched to uninfected people, adjusted for age and sex and stratified by SARS-CoV-2 variants, and risk in patients with a breakthrough SARS-CoV-2 infection compared with unvaccinated infected controls. Risks were compared using hazard ratios and risk differences per 10 000 patients measured during the early (30-180 days) and late (180-360 days) time periods after infection.

Results: Covid-19 infection was significantly associated with increased risks in early and late periods for anosmia and dysgeusia (hazard ratio 4.59 (95% confidence interval 3.63 to 5.80), risk difference 19.6 (95% confidence interval 16.9 to 22.4) in early period; 2.96 (2.29 to 3.82), 11.0 (8.5 to 13.6) in late period), cognitive impairment (1.85 (1.58 to 2.17), 12.8, (9.6 to 16.1); 1.69 (1.45 to 1.96), 13.3 (9.4 to 17.3)), dyspnoea (1.79 (1.68 to 1.90), 85.7 (76.9 to 94.5); 1.30 (1.22 to 1.38), 35.4 (26.3 to 44.6)), weakness (1.78 (1.69 to 1.88), 108.5, 98.4 to 118.6; 1.30 (1.22 to 1.37), 50.2 (39.4 to 61.1)), and palpitations (1.49 (1.35 to 1.64), 22.1 (16.8 to 27.4); 1.16 (1.05 to 1.27), 8.3 (2.4 to 14.1)) and with significant but lower excess risk for streptococcal tonsillitis and dizziness. Hair loss, chest pain, cough, myalgia, and respiratory disorders were significantly increased only during the early phase. Male and female patients showed minor differences, and children had fewer outcomes than adults during the early phase of covid-19, which mostly resolved in the late period. Findings remained consistent across SARS-CoV-2 variants. Vaccinated patients with a breakthrough SARS-CoV-2 infection had a lower risk for dyspnoea and similar risk for other outcomes compared with unvaccinated infected patients.

Conclusions: This nationwide study suggests that patients with mild covid-19 are at risk for a small number of health outcomes, most of which are resolved within a year from diagnosis.

Source: Mizrahi B, Sudry T, Flaks-Manov N, Yehezkelli Y, Kalkstein N, Akiva P, Ekka-Zohar A, Ben David SS, Lerner U, Bivas-Benita M, Greenfeld S. Long covid outcomes at one year after mild SARS-CoV-2 infection: nationwide cohort study. BMJ. 2023 Jan 11;380:e072529. doi: 10.1136/bmj-2022-072529. PMID: 36631153; PMCID: PMC9832503. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9832503/ (Full text)

Clinical Characteristics in the Acute Phase of COVID-19 That Predict Long COVID: Tachycardia, Myalgias, Severity, and Use of Antibiotics as Main Risk Factors, While Education and Blood Group B Are Protective

Abstract:

Background: Risk factors for developing long COVID are not clearly established. The present study was designed to determine if any sign, symptom, or treatment of the acute phase, or personal characteristics of the patient, is associated with the development of long COVID.
Methods: A cohort study was carried out, randomly selecting symptomatic COVID-19 patients and not vaccinated. The severity of the acute illness was assessed through the number of compatible COVID-19 symptoms, hospitalizations, and the symptom severity score using a 10-point visual analog scale.
Results: After multivariate analysis, a severity score ≥8 (RR 2.0, 95%CI 1.1–3.5, p = 0.022), hospitalization (RR 2.1, 95%CI 1.0–4.4, p = 0.039), myalgia (RR 1.9, 95%CI 1.08–3.6, p = 0.027), tachycardia (RR 10.4, 95%CI 2.2–47.7, p = 0.003), and use of antibiotics (RR 2.0, 95%CI 1.1–3.5, p = 0.022), was positively associated with the risk of having long COVID. Higher levels of education (RR 0.6, 95%CI 0.4–0.9, p = 0.029) and type positive B blood group (B + AB, RR 0.44, 95%CI 0.2–0.9, p = 0.044) were protective factors. The most important population attributable fractions (PAFs) for long COVID were myalgia (37%), severity score ≥8 (31%), and use of antibiotics (27%).
Conclusions: Further studies in diverse populations over time are needed to expand the knowledge that could lead us to prevent and/or treat long COVID.
Source: Guzman-Esquivel J, Mendoza-Hernandez MA, Guzman-Solorzano HP, Sarmiento-Hernandez KA, Rodriguez-Sanchez IP, Martinez-Fierro ML, Paz-Michel BA, Murillo-Zamora E, Rojas-Larios F, Lugo-Trampe A, Plata-Florenzano JE, Delgado-Machuca M, Delgado-Enciso I. Clinical Characteristics in the Acute Phase of COVID-19 That Predict Long COVID: Tachycardia, Myalgias, Severity, and Use of Antibiotics as Main Risk Factors, While Education and Blood Group B Are Protective. Healthcare. 2023; 11(2):197. https://doi.org/10.3390/healthcare11020197 https://www.mdpi.com/2227-9032/11/2/197 (Full text)

Converging Evidence of Similar Symptomatology of ME/CFS and PASC Indicating Multisystemic Dyshomeostasis

Abstract:

The purpose of this article is to review the evidence of similar symptomatology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-acute sequelae of SARS-CoV-2 infection (PASC).
Reanalysis of data from a study by Jason comparing symptom reports from two groups of ME/CFS and PASC patients shows a notably similar symptomatology. Symptom scores of the PASC group and the ME/CFS group correlated 0.902 (p < 0.0001) across items. The hypothesis is presented that ME/CFS and PASC are caused by a chronic state of multisystemic disequilibrium including endocrinological, immunological, and/or metabolic changes.
The hypothesis holds that a changed set point persistently pushes the organism towards a pathological dysfunctional state which fails to reset. To use an analogy of a thermostat, if the ‘off switch’ of a thermostat intermittently stops working, for periods the house would become warmer and warmer without limit. The hypothesis draws on recent investigations of the Central Homeostasis Network showing multiple interconnections between the autonomic system, central nervous system, and brain stem.
The hypothesis helps to explain the shared symptomatology of ME/CFS and PASC and the unpredictable, intermittent, and fluctuating pattern of symptoms of ME/CFS and PASC. The current theoretical approach remains speculative and requires in-depth investigation before any definite conclusions can be drawn.
Source: Marks DF. Converging Evidence of Similar Symptomatology of ME/CFS and PASC Indicating Multisystemic Dyshomeostasis. Biomedicines. 2023; 11(1):180. https://doi.org/10.3390/biomedicines11010180 https://www.mdpi.com/2227-9059/11/1/180 (Full text)

Toxin-like Peptides from the Bacterial Cultures Derived from Gut Microbiome Infected by SARS-CoV-2—New Data for a Possible Role in the Long COVID Pattern

Abstract:

It has been 3 years since the beginning of the SARS-CoV-2 outbreak, however it is as yet little known how to care for the acute COVID-19 and long COVID patients. COVID-19 clinical manifestations are of both pulmonary and extra-pulmonary types. Extra-pulmonary ones include extreme tiredness (fatigue), shortness of breath, muscle aches, hyposmia, dysgeusia, and other neurological manifestations.
In other autoimmune diseases, such as Parkinson’s disease (PD) or Alzheimer’s Disease (AD), it is well known that role of acetylcholine is crucial in olfactory dysfunction. We have already observed the presence of toxin-like peptides in plasma, urine, and faecal samples from COVID-19 patients, which are very similar to molecules known to alter acetylcholine signaling.  After observing the production of these peptides in bacterial cultures, we have performed additional proteomics analyses to better understand their behavior and reported the extended data from our latest in vitro experiment.
It seems that the gut microbiome continues to produce toxin-like peptides also after the decrease of RNA SARS-CoV-2 viral load at molecular tests. These toxicological interactions between the gut/human microbiome bacteria and the virus suggest a new scenario in the study of the clinical symptoms in long COVID and also in acute COVID-19 patients. It is discussed that in the bacteriophage similar behavior, the presence of toxins produced by bacteria continuously after viral aggression can be blocked using an appropriate combination of certain drugs.
Source: Brogna C, Cristoni S, Brogna B, Bisaccia DR, Marino G, Viduto V, Montano L, Piscopo M. Toxin-like Peptides from the Bacterial Cultures Derived from Gut Microbiome Infected by SARS-CoV-2—New Data for a Possible Role in the Long COVID Pattern. Biomedicines. 2023; 11(1):87. https://doi.org/10.3390/biomedicines11010087 https://www.mdpi.com/2227-9059/11/1/87 (Full text)

Long COVID: an estrogen-associated autoimmune disease?

Introduction:

Some people who have had severe to a moderate or mild form of COVID-19 disease may suffer from variable and debilitating symptoms for many months after the initial infection. This condition is commonly called “Long COVID”. An exact definition is missing, but symptoms with a duration of more than 2 months are typically considered as Long COVID. The condition is characterized by long-term sequelae and can involve a range of symptoms such as persistent fatigue, headache, shortness of breath, anosmia, muscle weakness, fever, cognitive dysfunction (brain fog), tachycardia, intestinal disorders, and skin manifestations. Long COVID syndrome bears a similarity to the post-infectious syndromes that followed the outbreaks of chikungunya and Ebola.

In general, women appear to be twice as likely to develop Long COVID as men, but only until around age 60, when the risk level becomes similar. In addition to being a woman, older age and a higher body mass index also seem to be risk factors for having Long COVID.

Source: Ortona E, Buonsenso D, Carfi A, Malorni W; Long Covid Kids study group. Long COVID: an estrogen-associated autoimmune disease? Cell Death Discov. 2021 Apr 13;7(1):77. doi: 10.1038/s41420-021-00464-6. PMID: 33850105; PMCID: PMC8042352.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8042352/ (Full text)

“Living like an empty gas tank with a leak”: Mixed methods study on post-acute sequelae of COVID-19

Abstract:

Background: The burden and presentation of post-acute sequela of SARS-CoV-2 infection (PASC) are a developing major public health concern.

Objectives: To characterize the burden of PASC in community-dwelling individuals and understand the experiences of people living with PASC.

Methods: This mixed-methods study of COVID-19 positive community-dwelling persons involved surveys and in-depth interviews. Main outcome was self-report of possible PASC symptoms 3 weeks or longer after positive COVID-19 test. In-depth interviews were guided by a semi-structured interview guide with open-ended questions and probes based on emerging literature on PASC and the impact of COVID-19.

Results: With a survey response rate of 70%, 442 participants were included in this analysis, mean (SD) age 45.4 (16.2) years, 71% female, 12% Black/African American. Compared to those with no PASC symptoms, persons who reported PASC symptoms were more likely to be older (mean age: 46.5 vs. 42; p = 0.013), female (74.3% vs. 61.2%; p = 0.010), to have pre-existing conditions (49.6% vs. 34%; p = 0.005), and to have been hospitalized for COVID-19 (14.2% vs. 2.9%; p = 0.002). About 30% of the participants experienced severe fatigue; the proportion of persons reporting severe fatigue was 7-fold greater in those with PASC symptoms (Adjusted Prevalence Ratio [aPR] 6.73, 95%CI: 2.80-16.18). Persons with PASC symptoms were more likely to report poor quality of life (16% vs. 5%, p<0.001) and worse mental health functioning (Mean difference: -1.87 95%CI: -2.38, -1.37, p<0.001). Themes from in-depth interviews revealed PASC was experienced as debilitating.

Conclusions: In this study, the prevalence of PASC among community-dwelling adults was substantial. Participants reported considerable coping difficulties, restrictions in everyday activities, invisibility of symptoms and experiences, and impediments to getting and receiving PASC care.

Source: Ogungbe O, Slone S, Alharthi A, Tomiwa T, Kumbe B, Bergman A, McNabb K, Smith Wright R, Farley JE, Dennison Himmelfarb CR, Cooper LA, Post WS, Davidson PM, Commodore-Mensah Y. “Living like an empty gas tank with a leak”: Mixed methods study on post-acute sequelae of COVID-19. PLoS One. 2022 Dec 30;17(12):e0279684. doi: 10.1371/journal.pone.0279684. PMID: 36584125; PMCID: PMC9803174. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9803174/ (Full text)

Cognitive impairments among patients in a long-COVID clinic: Prevalence, pattern and relation to illness severity, work function and quality of life

Abstract:

Background: A considerable proportion of people experience lingering symptoms after Coronavirus Disease 2019 (COVID-19). The aim of this study was to investigate the frequency, pattern and functional implications of cognitive impairments in patients at a long-COVID clinic who were referred after hospitalisation with COVID-19 or by their general practitioner.

Methods: Patients underwent cognitive screening and completed questionnaires regarding subjective cognition, work function and quality of life. Patients’ cognitive performance was compared with that of 150 age-, sex-, and education-matched healthy controls (HC) and with their individually expected performance calculated based on their age, sex and education.

Results: In total, 194 patients were assessed, on average 7 months (standard deviation: 4) after acute COVID-19.44-53 % of the patients displayed clinically relevant cognitive impairments compared to HC and to their expected performance, respectively. Moderate to large impairments were seen in global cognition and in working memory and executive function, while mild to moderate impairments occurred in verbal fluency, verbal learning and memory. Hospitalised (n = 91) and non-hospitalised (n = 103) patients showed similar degree of cognitive impairments in analyses adjusted for age and time since illness. Patients in the cognitively impaired group were older, more often hospitalised, had a higher BMI and more frequent asthma, and were more often female. More objective cognitive impairment was associated with more subjective cognitive difficulties, poorer work function and lower quality of life.

Limitations: The study was cross-sectional, which precludes causality inferences.

Conclusions: These findings underscore the need to assess and treat cognitive impairments in patients at long-COVID clinics.

Source: Miskowiak KW, Pedersen JK, Gunnarsson DV, Roikjer TK, Podlekareva D, Hansen H, Dall CH, Johnsen S. Cognitive impairments among patients in a long-COVID clinic: Prevalence, pattern and relation to illness severity, work function and quality of life. J Affect Disord. 2022 Dec 28;324:162-169. doi: 10.1016/j.jad.2022.12.122. Epub ahead of print. PMID: 36586593; PMCID: PMC9795797. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9795797/ (Full text)