Long COVID or post-COVID-19 syndrome: putative pathophysiology, risk factors, and treatments

Abstract:

Long COVID or post-COVID-19 syndrome first gained widespread recognition among social support groups and later in scientific and medical communities. This illness is poorly understood as it affects COVID-19 survivors at all levels of disease severity, even younger adults, children, and those not hospitalized. While the precise definition of long COVID may be lacking, the most common symptoms reported in many studies are fatigue and dyspnoea that last for months after acute COVID-19. Other persistent symptoms may include cognitive and mental impairments, chest and joint pains, palpitations, myalgia, smell and taste dysfunctions, cough, headache, and gastrointestinal and cardiac issues. Presently, there is limited literature discussing the possible pathophysiology, risk factors, and treatments in long COVID, which the current review aims to address.

In brief, long COVID may be driven by long-term tissue damage (e.g. lung, brain, and heart) and pathological inflammation (e.g. from viral persistence, immune dysregulation, and autoimmunity). The associated risk factors may include female sex, more than five early symptoms, early dyspnoea, prior psychiatric disorders, and specific biomarkers (e.g. D-dimer, CRP, and lymphocyte count), although more research is required to substantiate such risk factors. While preliminary evidence suggests that personalized rehabilitation training may help certain long COVID cases, therapeutic drugs repurposed from other similar conditions, such as myalgic encephalomyelitis or chronic fatigue syndrome, postural orthostatic tachycardia syndrome, and mast cell activation syndrome, also hold potential. In sum, this review hopes to provide the current understanding of what is known about long COVID.

Source: Yong SJ. Long COVID or post-COVID-19 syndrome: putative pathophysiology, risk factors, and treatments. Infect Dis (Lond). 2021 May 22:1-18. doi: 10.1080/23744235.2021.1924397. Epub ahead of print. PMID: 34024217. https://pubmed.ncbi.nlm.nih.gov/34024217/

Post-COVID-19 Syndrome: The Persistent Symptoms at the Post-viral Stage of the Disease. A Systematic Review of the Current Data

Abstract:

Whilst the entire world is battling the second wave of COVID-19, a substantial proportion of patients who have suffered from the condition in the past months are reporting symptoms that last for months after recovery, i. e., long-term COVID-19 symptoms. We aimed to assess the current evidence on the long-term symptoms in COVID-19 patients. We did a systematic review on PubMed, Web of Science, EMBASE, and Google Scholar from database inception to February 15, 2021, for studies on long-term COVID-19 symptoms.

We included all type of papers that reported at least one long-term COVID-19 symptom. We screened studies using a standardized data collection form and pooled data from published studies. Cohort cross-sectional, case-report, cases-series, case-control studies, and review were graded using specific quality assessment tools. Of 11,361 publications found following our initial search we assessed 218 full-text articles, of which 145 met all selection criteria. We found that 20.70% of reports on long-term COVID-19 symptoms were on abnormal lung functions, 24.13% on neurologic complaints and olfactory dysfunctions, and 55.17% on specific widespread symptoms, mainly chronic fatigue, and pain.

Despite the relatively high heterogeneity of the reviewed studies, our findings highlighted that a noteworthy proportion of patients who have suffered from SARS-CoV-2 infection present a “post-COVID syndrome.” The multifaceted understanding of all aspects of the COVID-19 pandemic, including these long-term symptoms, will allow us to respond to all the global health challenges, thus paving the way to a stronger public health.

Source: Salamanna F, Veronesi F, Martini L, Landini MP, Fini M. Post-COVID-19 Syndrome: The Persistent Symptoms at the Post-viral Stage of the Disease. A Systematic Review of the Current Data. Front Med (Lausanne). 2021 May 4;8:653516. doi: 10.3389/fmed.2021.653516. PMID: 34017846; PMCID: PMC8129035. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8129035/ (Full text)

Editorial: The Pathogenesis of Long-Term Neuropsychiatric COVID-19 and the Role of Microglia, Mitochondria, and Persistent Neuroinflammation: A Hypothesis

Abstract:

Persistent comorbidities occur in patients who initially recover from acute coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). ‘Long COVID’ involves the central nervous system (CNS), resulting in neuropsychiatric symptoms and signs, including cognitive impairment or ‘brain fog’ and chronic fatigue syndrome. There are similarities in these persistent complications between SARS-CoV-2 and the Ebola, Zika, and influenza A viruses. Normal CNS neuronal mitochondrial function requires high oxygen levels for oxidative phosphorylation and ATP production. Recent studies have shown that the SARS-CoV-2 virus can hijack mitochondrial function. Persistent changes in cognitive functioning have also been reported with other viral infections. SARS-CoV-2 infection may result in long-term effects on immune processes within the CNS by causing microglial dysfunction. This short opinion aims to discuss the hypothesis that the pathogenesis of long-term neuropsychiatric COVID-19 involves microglia, mitochondria, and persistent neuroinflammation.

Source: Stefano GB, Büttiker P, Weissenberger S, Martin A, Ptacek R, Kream RM. Editorial: The Pathogenesis of Long-Term Neuropsychiatric COVID-19 and the Role of Microglia, Mitochondria, and Persistent Neuroinflammation: A Hypothesis. Med Sci Monit. 2021 May 10;27:e933015. doi: 10.12659/MSM.933015. PMID: 34016942. https://pubmed.ncbi.nlm.nih.gov/34016942/

Case Study Suggests Young People Susceptible To Chronic Fatigue Syndrome After Covid-19

Press Release:

With more adolescents and young adults being treated for COVID-19, clinicians are concerned that these people also will start showing post-COVID — or “long haul” — symptoms from their bouts with the virus. A recent Johns Hopkins Medicine review of three case studies provides some of the first evidence that one serious post-COVID problem may be myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), the complex, multisystem disorder previously known as chronic fatigue syndrome.

The findings were published April 29 in the journal Frontiers in Medicine.

“In the three patients studied — all of whom had confirmed or highly probable COVID-19 infections early in the pandemic — we observed ME/CFS-like symptoms within the first two weeks of illness,” says Peter Rowe, M.D., director of the Chronic Fatigue Clinic at Johns Hopkins Children’s Center and professor of pediatrics at the Johns Hopkins University School of Medicine. “At six months following their illness, all three still met the criteria for being diagnosed with ME/CFS.”

In a recent report, the U.S. Centers for Disease Control and Prevention (CDC) noted that U.S. hospitals are seeing more adolescents and young adults admitted with COVID-19 as more contagious variants of SARS-CoV-2 — the virus that causes the disease — spread. The agency believes that the youthful case surge may be the result of those ages 10 to 24 being among the last prioritized to get the coronavirus vaccines, and the fact that many who are eligible have yet to receive their shots. Also, the CDC says, this group is more likely to be involved in high-risk behaviors such as playing close-contact sports and going out to bars.

The three patients evaluated in the recent study were a 19-year-old man and two women, ages 22 and 30, whose COVID-19 symptoms began between April and June 2020, and who were referred to the Chronic Fatigue Clinic between August and October of the same year. Symptoms of orthostatic intolerance — a group of clinical conditions that includes fatigue, lightheadedness and difficulty concentrating, and are linked with greater than 90% of the people with ME/CFS — were prominent in all three from the outset of their COVID-19 illness.

A six-month post-COVID symptom onset examination, including evaluations of movement, neurological function and continued orthostatic intolerance, was conducted on each of the patients to determine if ME/CFS could be diagnosed. All three easily met the criteria.

Interestingly, Rowe says, all three patients had relatively mild COVID-19 respiratory symptoms and none required hospitalization, yet it appears to have translated into the more serious secondary problem of ME/CFS for them all.

“This finding is consistent with previous studies in older patients with COVID-19 who showed persistent fatigue months after infection, regardless of the severity of the initial infection,” he explains. “This raises the question of how many ME/CFS cases before the COVID-19 pandemic might have been due to mild, subclinical or asymptomatic viral infections [such as Epstein-Barr virus or human herpesvirus 6], including cases in adolescents, young adults and older people.”

Rowe and his colleagues feel that further research is needed to define the biological mechanism by which ME/CFS arises from COVID-19, and then use that insight to develop treatment strategies that can return patients with post-COVID ME/CFS back to their previous quality of life.

Rowe is available for interviews.

https://www.hopkinsmedicine.org/news/newsroom/news-releases/covid-19-story-tip-case-study-suggests-young-people-may-be-susceptible-to-chronic-fatigue-following-covid-19

Media Contact: Michael E. Newman, mnewma25@jhmi.edu

COVID-19 symptoms over time: comparing long-haulers to ME/CFS

Abstract:

Introduction: Our objective was to determine which symptoms among long-hauler COVID-19 patients change over time, and how their symptoms compare to another chronic illness group.

Methods: 278 long-haulers completed two symptom questionnaires at one time point, with one recounting experiences during the first two weeks of their illness, an average of 21.7 weeks prior. We used a comparison group of 502 patients diagnosed with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Participants completed a standardized symptom questionnaire and a list of additional CDC COVID-19 symptoms.

Results: Over time, the long-haulers reported an overall reduction of most symptoms including unrefreshing sleep and post-exertional malaise, but an intensification of neurocognitive symptoms. When compared to ME/CFS, the COVID-19 sample was initially more symptomatic for the immune and orthostatic domains but over time, the long-haulers evidenced significantly less severe symptoms than those with ME/CFS, except in the orthostatic domain. Among the COVID-19 long haulers, several neurocognitive symptoms got worse over time, whereas improvements occurred in most other areas.

Conclusions: These types of differential patterns of symptoms over time might contribute to helping better understand the pathophysiology of those reporting prolonged illness following COVID-19.

Source: Leonard A. Jason, Mohammed F. Islam, Karl Conroy, Joseph Cotler, Chelsea Torres, Mady Johnson & Brianna Mabie (2021) COVID-19 symptoms over time: comparing long-haulers to ME/CFS, Fatigue: Biomedicine, Health & Behavior, DOI: 10.1080/21641846.2021.1922140 https://www.tandfonline.com/doi/full/10.1080/21641846.2021.1922140

Humility and Acceptance: Working Within Our Limits With Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Synopsis:
The term long COVID was coined by patients to describe the long-term consequences of COVID-19. One year into the pandemic, it was clear that all patients—those hospitalized with COVID-19 and those who lived with the disease in the community—were at risk of developing debilitating sequelae that would impact their quality of life. Patients with long COVID asked for rehabilitation. Many of them, including previously healthy and fit clinicians, tried to fight postviral fatigue with exercise-based rehabilitation. We observed a growing number of patients with long COVID who experienced adverse effects from exercise therapy and symptoms strikingly similar to those of myalgic encephalomyelitis (ME). Community-based physical therapists, including those in private practice, unaware of safety issues, are preparing to help an influx of patients with long COVID. In this editorial, we expose growing concerns about long COVID and ME. We issue safety recommendations for rehabilitation and share resources to improve care for those with postviral illnesses. J Orthop Sports Phys Ther 2021;51(5):197–200. doi:10.2519/jospt.2021.0106

Source: Simon DécaryIsabelle GabourySabrina PoirierChristiane GarciaScott SimpsonMichelle BullDarren Brown, and Frédérique Daigle. Humility and Acceptance: Working Within Our Limits With Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Journal of Orthopaedic & Sports Physical Therapy 2021 51:5197-200. https://www.jospt.org/doi/10.2519/jospt.2021.0106

Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)-A Systemic Review and Comparison of Clinical Presentation and Symptomatology

Abstract:

Background and Objectives: Long COVID defines a series of chronic symptoms that patients may experience after resolution of acute COVID-19. Early reports from studies with patients with long COVID suggests a constellation of symptoms with similarities to another chronic medical illness-myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). A review study comparing and contrasting ME/CFS with reported symptoms of long COVID may yield mutualistic insight into the characterization and management of both conditions.

Materials and Methods: A systemic literature search was conducted in MEDLINE and PsycInfo through to 31 January 2021 for studies related to long COVID symptomatology. The literature search was conducted in accordance with PRISMA methodology.

Results: Twenty-one studies were included in the qualitative analysis. Long COVID symptoms reported by the included studies were compared to a list of ME/CFS symptoms compiled from multiple case definitions. Twenty-five out of 29 known ME/CFS symptoms were reported by at least one selected long COVID study.

Conclusions: Early studies into long COVID symptomatology suggest many overlaps with clinical presentation of ME/CFS. The need for monitoring and treatment for patients post-COVID is evident. Advancements and standardization of long COVID research methodologies would improve the quality of future research, and may allow further investigations into the similarities and differences between long COVID and ME/CFS.

Source: Wong TL, Weitzer DJ. Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)-A Systemic Review and Comparison of Clinical Presentation and Symptomatology. Medicina (Kaunas). 2021 Apr 26;57(5):418. doi: 10.3390/medicina57050418. PMID: 33925784.  https://pubmed.ncbi.nlm.nih.gov/33925784/

COVID-19 and post-infectious myalgic encephalomyelitis/chronic fatigue syndrome: a narrative review

Abstract:

Coronavirus disease 2019 (COVID-19) is a viral infection which can cause a variety of respiratory, gastrointestinal, and vascular symptoms. The acute illness phase generally lasts no more than 2–3 weeks. However, there is increasing evidence that a proportion of COVID-19 patients experience a prolonged convalescence and continue to have symptoms lasting several months after the initial infection.

A variety of chronic symptoms have been reported including fatigue, dyspnea, myalgia, exercise intolerance, sleep disturbances, difficulty concentrating, anxiety, fever, headache, malaise, and vertigo. These symptoms are similar to those seen in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a chronic multi-system illness characterized by profound fatigue, sleep disturbances, neurocognitive changes, orthostatic intolerance, and post-exertional malaise. ME/CFS symptoms are exacerbated by exercise or stress and occur in the absence of any significant clinical or laboratory findings.

The pathology of ME/CFS is not known: it is thought to be multifactorial, resulting from the dysregulation of multiple systems in response to a particular trigger. Although not exclusively considered a post-infectious entity, ME/CFS has been associated with several infectious agents including Epstein–Barr Virus, Q fever, influenza, and other coronaviruses. There are important similarities between post-acute COVID-19 symptoms and ME/CFS. However, there is currently insufficient evidence to establish COVID-19 as an infectious trigger for ME/CFS. Further research is required to determine the natural history of this condition, as well as to define risk factors, prevalence, and possible interventional strategies.

Source: Poenaru S, Abdallah SJ, Corrales-Medina V, Cowan J. COVID-19 and post-infectious myalgic encephalomyelitis/chronic fatigue syndrome: a narrative review. Therapeutic Advances in Infectious Disease. January 2021. doi:10.1177/20499361211009385 https://journals.sagepub.com/doi/full/10.1177/20499361211009385 (Full article)

Long-COVID syndrome-associated brain fog and chemofog: Luteolin to the rescue

Abstract:

COVID-19 leads to severe respiratory problems, but also to long-COVID syndrome associated primarily with cognitive dysfunction and fatigue. Long-COVID syndrome symptoms, especially brain fog, are similar to those experienced by patients undertaking or following chemotherapy for cancer (chemofog or chemobrain), as well in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or mast cell activation syndrome (MCAS). The pathogenesis of brain fog in these illnesses is presently unknown but may involve neuroinflammation via mast cells stimulated by pathogenic and stress stimuli to release mediators that activate microglia and lead to inflammation in the hypothalamus. These processes could be mitigated by phytosomal formulation (in olive pomace oil) of the natural flavonoid luteolin.

Source: Theoharides TC, Cholevas C, Polyzoidis K, Politis A. Long-COVID syndrome-associated brain fog and chemofog: Luteolin to the rescue. Biofactors. 2021 Apr 12. doi: 10.1002/biof.1726. Epub ahead of print. PMID: 33847020. https://pubmed.ncbi.nlm.nih.gov/33847020/

The neurological symptoms of COVID-19: a systematic overview of systematic reviews, comparison with other neurological conditions and implications for healthcare services

Abstract:

Aims: In response to the rapid spread of COVID-19, this paper provides health professionals with better accessibility to available evidence, summarising findings from a systematic overview of systematic reviews of the neurological symptoms seen in patients with COVID-19. Implications of so-called ‘Long Covid’ on neurological services and primary care and similarities with other neurological disorders are discussed.

Methods: Firstly, a systematic overview of current reviews of neurological symptoms of COVID-19 was conducted. Secondly, the implications of these findings are discussed in relation to the potential effect on neurological services and the similarities in the experience of patients with COVID-19 and those with other neurological disorders. A total of 45 systematic reviews were identified within seven databases, published between 11 April 2020 and 15 October 2020, following a search in June 2020, updated on 20 October 2020.

Results: The results indicated that COVID-19 exhibits two types of neurological symptoms; life-threatening symptoms such as Guillain-Barre Syndrome (GBS) and encephalitis, and less devastating symptoms such as fatigue and myalgia. Many of these so-called lesser symptoms appear to be emerging as longer-term for some sufferers and have been recently labelled Long Covid. When compared, these less devastating symptoms are very similar to other neurological conditions such as chronic fatigue syndrome (CFS) and functional neurological disorder (FND).

Conclusion: Implications for neurological healthcare services in the United Kingdom (UK) may include longer waiting times and a need for more resources (including more qualified health professionals). There is also a possible change-effect on health professionals’ perceptions of other neurological conditions such as CFS and FND. Future research is recommended to explore changes in health professionals’ perceptions of neurological symptoms because of COVID-19.

Source: Wildwing T, Holt N. The neurological symptoms of COVID-19: a systematic overview of systematic reviews, comparison with other neurological conditions and implications for healthcare services. Ther Adv Chronic Dis. 2021 Jan 28;12:2040622320976979. doi: 10.1177/2040622320976979. PMID: 33796241; PMCID: PMC7970685. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7970685/  (Full text)