Therapeutic trials for long COVID-19: A call to action from the interventions taskforce of the RECOVER initiative

Equity in research: a global consensus statement on the urgency of including children in long COVID clinical trials

Long COVID, a post-acute infection syndrome triggered by SARS-CoV-2, is now recognised as a major cause of disability worldwide [1], affecting both children and adults. The World Health Organization (WHO) defines long COVID in children as: “new onset of symptoms impacting everyday functioning that last at least 2 months, occurring within 3 months of probable or confirmed acute SARS-CoV-2 infection” [2]. While elegantly designed clinical trials have been established to identify effective treatments for long COVID, children are notably excluded. We propose that inclusion of children in long COVID clinical trials is justified, and unwarranted age-related exclusion criteria for current clinical trial designs impose unintentional and unnecessary barriers to treatment for children with long COVID.

Efforts are urgently needed to intentionally address this inequity in long COVID research to include children early in clinical trial design. https://bit.ly/3RMGmYz

Challenges and Opportunities for Post-COVID Pulmonary Disease: A Focused Review of Immunomodulation

The resolution of the recent COVID-19 pandemic still requires attention, since the consequences of having suffered the infection, even in mild cases, are associated with several acute and chronic pathological conditions referred to as post-COVID syndrome (PCS). PCS often manifests with pulmonary disease and, in up to 9% of cases, a more serious complication known as post-COVID-19 pulmonary fibrosis (PC19-PF), which has a similar clinical course as idiopathic pulmonary fibrosis (IPF). Generating knowledge to provide robust evidence about the clinical benefits of different therapeutic strategies to treat the pulmonary effects of PCS can provide new insights to amplify therapeutic options for these patients. We present evidence found after a scoping review, following extended PRIMSA guidelines, for the use of immunomodulators in pulmonary PCS. We start with a brief description of the immunomodulatory properties of the relevant drugs, their clinically proven efficacy for viral infections and chronic inflammatory conditions, and their use during the COVID-19 pandemic. We emphasize the need for well-designed clinical trials to improve our understanding the physiopathology of pulmonary PCS and PC19-PF and also to determine the efficacy and safety of candidate treatments.

Long COVID: Pathophysiology, current concepts, and future directions

Long COVID, an umbrella term referring to a variety of symptoms and clinical presentations that emerges in a subset of patients after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has a significant effect on quality of life and places a substantial burden on health care systems worldwide, straining financial and human resources. The pathophysiology of long COVID remains incompletely understood, though several hypotheses have been proposed to explain different aspects of this complex condition. SARS-CoV-2 persistence, direct organ damage, innate and adaptive immune system perturbation, autoimmunity, latent virus reactivation, endothelial dysfunction, and microbiome disturbances are among the most relevant avenues for elucidating the evolution, complexity, and mechanisms of long COVID. Active investigation regarding potential biomarkers for long COVID and its associated disease endotypes highlights the role of inflammatory mediators, immunophenotyping, and multiomics approaches. Further advances in understanding long COVID are needed to inform current and future therapeutics.

Caveolin Scaffolding Domain (CSD) Peptide LTI-2355 Modulates the Phagocytic and Synthetic Activity of Lung-Derived Myeloid Cells in Idiopathic Pulmonary Fibrosis (IPF) and Post-Acute Sequelae of COVID Fibrosis (PASC-F)

Rationale: The role of the innate immune system in idiopathic pulmonary fibrosis (IPF) remains poorly understood. However, a functional myeloid compartment is required to remove dying cells and cellular debris, as well as to mediate innate immune responses against pathogens. Aberrant macrophage activity has been described in patients with post-acute sequelae of COVID fibrosis (PASC-F), and caveolin scaffolding domain (CSD) peptides have been found to attenuate inflammation and fibrosis in mouse lung injury models. Therefore, we examined, for the first time, the effects of CSD peptide LTI-2355 on the functional and synthetic properties of human myeloid cells isolated from lung explant tissue of donor lungs as well as IPF and PASC-F lung explant tissue. Methods and Results: CD45+ myeloid cells isolated from lung explant tissue from IPF and PASC-F patients exhibited an impaired capacity to clear autologous dead cells and cellular debris. The uptake of pathogen-coated bioparticles was impaired in myeloid cells from both fibrotic patient groups independent of the type of pathogen, highlighting an intrinsic functional cell impairment. LTI-2355 improved the phagocytic activity of both IPF and PASC-F myeloid cells, and this improvement was paired with decreased proinflammatory and pro-fibrotic synthetic activity. LTI-2355 was also shown to primarily target CD206-expressing IPF and PASC-F myeloid cells. Conclusions: Primary myeloid cells from IPF and PASC-F patients exhibit dysfunctional phagocytic and synthetic properties that are modulated by LTI-2355. LTI-2355 treatment of IPF myeloid cells resulted in significantly reduced sCD163, IFN-α2, IFN-γ, IL-2, IL-10, IL-12p40, and MMP-1 in the cell supernatant. This study highlights an additional mechanism of action of the CSD peptide in the treatment of IPF and progressive fibrotic lung disease.

A psychological model of predictive factors of distress following long COVID

BACKGROUND

Long COVID, described as "the continuation or development of new symptoms 3 months after the initial SARS-CoV-2 infection", is estimated to affect at least 10-20 % of all cases of acute SARS-CoV-2 infection. Because of its novelty, information regarding the experience of Long COVID is still emerging.

METHODS

This study examines psychological distress in two long COVID populations, and their experience of fatigue, cognitive failures, experiential avoidance, rumination, and perceived injustice. Participants were recruited via a long COVID hospital clinic and online self-diagnosing samples. Participants completed a battery of scales to measure psychological distress, fatigue, cognitive dysfunction, avoidance and rumination behaviours and the experience of injustice.

RESULTS

It was found that the regression model tested accounted for a significant amount of the variance in psychological distress (R2 = 0.675). Cognitive failures, avoidance, rumination, and injustice experiences significantly contributed to the experience of psychological distress and a moderated mediation accounted for the effect of fatigue on psychological distress.

LIMITATIONS

The self-report measures in this study did not include objective measures of symptom severity. Cross-sectional data collected at a single time-point may not capture the dynamic nature of long COVID symptoms.

CONCLUSIONS

These findings identify contributing factors to the experience of psychological distress in the long COVID population, providing direction to explore supportive interventions.

mTORC1 syndrome (TorS): unifying paradigm for PASC, ME/CFS and PAIS

Post-acute SarS-Cov2 (PASC), Myalgia encephalomyelitis/Chronic fatigue syndrome (ME/CFS) and Post-acute infection syndrome (PAIS) consist of chronic post-acute infectious syndromes, sharing exhaustive fatigue, post exertional malaise, intermittent pain, postural tachycardia and neuro-cognitive-psychiatric dysfunction. However, the concerned shared pathophysiology is still unresolved in terms of upstream drivers and transducers. Also, risk factors which may determine vulnerability/progression to the chronic phase still remain to be defined. In lack of drivers and a cohesive pathophysiology, the concerned syndromes still remain unmet therapeutic needs. 'mTORC1 Syndrome' (TorS) implies an exhaustive disease entity driven by sustained hyper-activation of the mammalian target of rapamycin C1 (mTORC1), and resulting in a variety of disease aspects of the Metabolic Syndrome (MetS), non-alcoholic fatty liver disease, chronic obstructive pulmonary disease, some cancers, neurodegeneration and other [Bar-Tana in Trends Endocrinol Metab 34:135-145, 2023]. TorS may offer a cohesive insight of PASC, ME/CFS and PAIS drivers, pathophysiology, vulnerability and treatment options.

Virus-Induced Pathogenic Antibodies: Lessons from Long COVID and Dengue Hemorrhage Fever

Virus-induced antibodies represent a dual-edged sword in the immune response to viral infections. While antibodies are critical for neutralizing pathogens, some can paradoxically exacerbate disease severity through mechanisms such as antibody-dependent enhancement (ADE), autoantibody, and prolonged inflammation. Long coronavirus disease (COVID) and dengue hemorrhagic fever (DHF) exemplify conditions where pathogenic antibodies play a pivotal role in disease progression. Long COVID is associated with persistent immune dysregulation and autoantibody production, leading to chronic symptoms and tissue damage. In DHF, pre-existing antibodies against dengue virus contribute to ADE, amplifying viral replication, immune activation, and vascular permeability. This review explores the mechanisms underlying these pathogenic antibody responses, highlighting the shared pathways of immune dysregulation and comparing the distinct features of both conditions. By examining these studies, we identify key lessons for therapeutic strategies, vaccine design, and future research aimed at mitigating the severe outcomes of viral infections.

Long COVID for the Rheumatologist: Current Understanding and Approach to Management

There are estimated tens of millions of individuals throughout the world suffering from a variety of postinfectious sequela following infection with severe acute respiratory syndrome coronavirus 2 also commonly referred to as long coronavirus disease (COVID). Long COVID is providing an opportunity for the field of rheumatology to explore the relationship between similar syndromes including fibromyalgia seen in patients with underlying inflammatory and noninflammatory rheumatic diseases, as well as other postacute infectious sequela and bring our field's traditional skill sets to bear on improving our understanding of these disorders and the care of such patients.

The impact of COVID-19 on accelerating of immunosenescence and brain aging

The COVID-19 pandemic, caused by the novel coronavirus SARS-CoV-2, has profoundly impacted global health, affecting not only the immediate morbidity and mortality rates but also long-term health outcomes across various populations. Although the acute effects of COVID-19 on the respiratory system have initially been the primary focus, it is increasingly evident that the virus can have significant impacts on multiple physiological systems, including the nervous and immune systems. The pandemic has highlighted the complex interplay between viral infection, immune aging, and brain health, that can potentially accelerate neuroimmune aging and contribute to the persistence of long COVID conditions. By inducing chronic inflammation, immunosenescence, and neuroinflammation, COVID-19 may exacerbate the processes of neuroimmune aging, leading to increased risks of cognitive decline, neurodegenerative diseases, and impaired immune function. Key factors include chronic immune dysregulation, oxidative stress, neuroinflammation, and the disruption of cellular processes. These overlapping mechanisms between aging and COVID-19 illustrate how the virus can induce and accelerate aging-related processes, leading to an increased risk of neurodegenerative diseases and other age-related conditions. This mini-review examines key features and possible mechanisms of COVID-19-induced neuroimmune aging that may contribute to the persistence and severity of long COVID. Understanding these interactions is crucial for developing effective interventions. Anti-inflammatory therapies, neuroprotective agents, immunomodulatory treatments, and lifestyle interventions all hold potential for mitigating the long-term effects of the virus. By addressing these challenges, we can improve health outcomes and quality of life for millions affected by the pandemic.

Recovery From Long COVID: The Role of Bioelectric Meridian Therapy in Restoring Health and Well-Being

This case report explores the journey to a healthier life of a 57-year-old man who stayed athletic after contracting COVID-19 during a trip to a foreign country. He had minimal symptoms in the beginning. He started with a dull cough, but the symptoms then progressed to loss of taste and smell, mental fatigue, and nerve problems. In this case study, traditional cures helped only to some extent. Out of frustration with these symptoms, the patient started bioelectric meridian therapy (BMT) in August 2021 and benefited from it. The patient described progressive sensation, cognition, and muscle power enhancement during six months of BMT sessions. The therapy relieved the muscles' stiffness and regulated the bio-energy circulation to improve the general quality of life and ease physical exertion operations. The case affirms how supportive modalities such as BMT help handle the after-effects of COVID-19. The patients' recovery involved precise mental concentration, return of appetite, and regained vigor, which improved the patient's life. This case report shows how integrative approaches may be helpful when it comes to the reactivation of health processes after virus infection.

Overlapping conditions in Long COVID at a multisite academic center

Background

Many patients experience persistent symptoms after COVID-19, a syndrome referred to as Long COVID (LC). The goal of this study was to identify novel new or worsening comorbidities self-reported in patients with LC.

Methods

Patients diagnosed with LC (n = 732) at the Mayo Long COVID Care Clinic in Rochester, Minnesota and Jacksonville, Florida were sent questionnaires to assess the development of new or worsening comorbidities following COVID-19 compared to patients with SARS-CoV-2 that did not develop LC (controls). Both groups were also asked questions screening for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), generalized joint hypermobility (GJH) and orthostatic intolerance. 247 people with LC (33.7%) and 40 controls (50%) responded to the surveys.

Results

In this study LC patients averaged 53 years of age and were predominantly White (95%) women (75%). The greatest prevalence of new or worsening comorbidities following SARS-CoV-2 infection in patients with LC vs. controls reported in this study were pain (94.4% vs. 0%, p < 0.001), neurological (92.4% vs. 15.4%, p < 0.001), sleep (82.8% vs. 5.3%, p < 0.001), skin (69.8% vs. 0%, p < 0.001), and genitourinary (60.6% vs. 25.0%, p = 0.029) issues. 58% of LC patients screened positive for ME/CFS vs. 0% of controls (p < 0.001), 27% positive for GJH compared to 10% of controls (p = 0.026), and a positive average score of 4.0 on orthostatic intolerance vs. 0 (p < 0.001). The majority of LC patients with ME/CFS were women (77%).

Conclusion

We found that comorbidities across 12 surveyed categories were increased in patients following SARS-CoV-2 infection. Our data also support the overlap of LC with ME/CFS, GJH, and orthostatic intolerance. We discuss the pathophysiologic, research, and clinical implications of identifying these conditions with LC.

Post-viral symptoms and conditions are more frequent in COVID-19 than influenza, but not more persistent

BACKGROUND

Post-viral symptoms have long been known in the medical community but have received more public attention during the COVID-19 pandemic. Many post-viral symptoms were reported as particularly frequent after SARS-CoV-2 infection. However, there is still a lack of evidence regarding the specificity, frequency and persistence of these symptoms in comparison to other viral infectious diseases such as influenza.

METHODS

We investigated a large population-based cohort based on German routine healthcare data. We matched 573,791 individuals with a PCR-test confirmed SARS-CoV-2 infection from the year 2020 to contemporary controls without SARS-CoV-2 infection and controls from the last influenza outbreak in 2018 and followed them up to 18 months.

RESULTS

We found that post-viral symptoms as defined for COVID-19 by the WHO as well as tissue damage were more frequent among the COVID-19 cohort than the influenza or contemporary control cohort. The persistence of post-viral symptoms was similar between COVID-19 and influenza.

CONCLUSION

Post-viral symptoms following SARS-CoV-2 infection constitute a substantial disease burden as they are frequent and often persist for many months. As COVID-19 is becoming endemic, the disease must not be trivialized. Research should focus on the development of effective treatments for post-viral symptoms.

A practical framework for Long COVID treatment in primary care

Long COVID is a complex, multisystem illness with a poorly understood pathophysiology, absence of specific diagnostic tests or criteria, or evidence-based treatments. With over 200 identified symptoms and approximately 10% of COVID-19 cases resulting in Long COVID, it is a challenge to provide comprehensive treatment at a scale commensurate with the illness burden. The diverse manifestations of Long COVID, encompassing numerous medical specialties, typically place primary care providers (PCPs) at the forefront of management, navigating an evolving landscape of research and lack of evidence-based guidelines. This paper presents a pragmatic, structured framework for Long COVID management in primary care, integrating current knowledge and best practices. The approach is individualized, addressing Long COVID's broad symptomatology through a four-step framework. The first step focuses on energy management strategies, emphasizing the prevention of post-exertional malaise, a cardinal feature of Long COVID. The second step, intentional rehabilitation, employs carefully titrated multidisciplinary modalities to address physical, cognitive, and emotional domains. The third step utilizes symptomatic management through both pharmacological and non-pharmacological interventions, targeting debilitating symptoms like fatigue, insomnia, and chronic pain. The fourth step outlines an approach to trialing experimental, targeted therapies that may impact Long COVID's underlying pathophysiology. These treatments, while experimental and lacking quality evidence in Long COVID, may be available off-label on an individual basis following a thorough risk-benefit discussion. This stepwise framework can equip PCPs to effectively address the most common and disabling symptoms of Long COVID, individualize care, and remain attuned to the evolving scientific understanding of the condition.

A description of the development of an innovative multi-component long COVID treatment program based on central sensitization with preliminary patient satisfaction data

OBJECTIVE

Estimates of the prevalence of Long COVID in the United States or worldwide are imprecise, but millions of people are thought to be affected. No effective treatment exists for the often devastating symptoms of Long COVID. Central Sensitization has been postulated as a causal/explanatory mechanism for developing Long COVID. No treatment to date has targeted Central Sensitization. The present cross-sectional study describes the first 140 patients treated in a multi-component treatment program that targets Central Sensitization to reduce symptom burden, improve functioning, and lower the psychological distress observed in these patients.

METHODS

140 patients diagnosed with Long COVID after an extensive medical evaluation were assessed for function, depression, and pain catastrophizing using questionnaires and patient satisfaction measures after completion of a 16-h Cognitive Behavioral Therapy treatment program focused on Central Sensitization.

RESULTS

Upon admission, patients diagnosed with Long COVID were significantly impaired in their ability to function due to their symptoms. Further, 70% of the patients were depressed. Pain catastrophizing was observed in up to 20% of patients.

CONCLUSION

Patient satisfaction measures were high for the sample at the end of the treatment program suggesting that a multicomponent treatment program targeting Central Sensitization is acceptable to patients. Further research is needed to explore the effectiveness and durability of this treatment approach.

Herbal medicines for long COVID: A phase 2 pilot clinical study

Background

Infections of Coronavirus Disease-2019 (COVID-19) can cause long-term effects known as long COVID. This pilot study aimed to evaluate the feasibility of a clinical study as well as the efficacy and safety of traditional East Asian herbal medicines in alleviating fatigue and cognitive dysfunction in patients with long COVID.

Methods

This prospective pilot study investigated the use of three types of herbal medicines, Bojungikgi-tang (BIT), Kyungok-go (KOG), and Cheonwangbosim-dan (CBD), for a 12-week period as potential treatments for fatigue and cognitive dysfunction in patients with long COVID. Forty-five patients with long COVID were recruited, and one of three drugs was given based on the patient's symptoms and pattern identification. The effect of herbal medications on fatigue and cognitive function outcomes was assessed over a 36-week period, with patient adherence closely monitored.

Results

After 12 weeks of herbal drug administration, fatigue symptoms improved significantly across all groups, with treatment success rates of 80 %, 53.33 %, and 46.67 % in the BIT, KOG, and CBD groups, respectively. However, cognitive dysfunction symptoms showed less improvement, with treatment success rates of 40 %, 46.67 %, and 13.33 % in the BIT, KOG, and CBD groups, respectively. All adverse events reported were mild and unrelated to the medication. The study design was found to be feasible with high medication adherence.

Conclusions

This study demonstrated the feasibility of conducting a clinical trial with three herbal medicines to treat long COVID symptoms like fatigue and cognitive dysfunction.

Research evidence on the management of the cognitive impairment component of the post-COVID condition: a qualitative systematic review

BACKGROUND

Cognitive impairment (CI) is one of the most prevalent and burdensome consequences of COVID-19 infection, which can persist up to months or even years after remission of the infection. Current guidelines on post-COVID CI are based on available knowledge on treatments used for improving CI in other conditions. The current review aims to provide an updated overview of the existing evidence on the efficacy of treatments for post-COVID CI.

METHODS

A systematic literature search was conducted for studies published up to December 2023 using three databases (PubMed-Scopus-ProQuest). Controlled and noncontrolled trials, cohort studies, case series, and reports testing interventions on subjects with CI following COVID-19 infection were included.

RESULTS

After screening 7790 articles, 29 studies were included. Multidisciplinary approaches, particularly those combining cognitive remediation interventions, physical exercise, and dietary and sleep support, may improve CI and address the different needs of individuals with post-COVID-19 condition. Cognitive remediation interventions can provide a safe, cost-effective option and may be tailored to deficits in specific cognitive domains. Noninvasive brain stimulation techniques and hyperbaric oxygen therapy showed mixed and preliminary results. Evidence for other interventions, including pharmacological ones, remains sparse. Challenges in interpreting existing evidence include heterogeneity in study designs, assessment tools, and recruitment criteria; lack of long-term follow-up; and under-characterization of samples in relation to confounding factors.

CONCLUSIONS

Further research, grounded on shared definitions of the post-COVID condition and on the accurate assessment of COVID-related CI, in well-defined study samples and with longer follow-ups, is crucial to address this significant unmet need.

Nirmatrelvir-Ritonavir and Symptoms in Adults With Postacute Sequelae of SARS-CoV-2 Infection: The STOP-PASC Randomized Clinical Trial

Importance

There is an urgent need to identify treatments for postacute sequelae of SARS-CoV-2 infection (PASC).

Objective

To assess the efficacy of a 15-day course of nirmatrelvir-ritonavir in reducing the severity of select PASC symptoms.

Design, Setting, and Participants

This was a 15-week blinded, placebo-controlled, randomized clinical trial conducted from November 2022 to September 2023 at Stanford University (California). The participants were adults with moderate to severe PASC symptoms of 3 months or longer duration.

Interventions

Participants were randomized 2:1 to treatment with oral nirmatrelvir-ritonavir (NMV/r, 300 mg and 100 mg) or with placebo-ritonavir (PBO/r) twice daily for 15 days.

Main Outcomes and Measures

Primary outcome was a pooled severity of 6 PASC symptoms (fatigue, brain fog, shortness of breath, body aches, gastrointestinal symptoms, and cardiovascular symptoms) based on a Likert scale score at 10 weeks. Secondary outcomes included symptom severity at different time points, symptom burden and relief, patient global measures, Patient-Reported Outcomes Measurement Information System (PROMIS) measures, orthostatic vital signs, and sit-to-stand test change from baseline.

Results

Of the 155 participants (median [IQR] age, 43 [34-54] years; 92 [59%] females), 102 were randomized to the NMV/r group and 53 to the PBO/r group. Nearly all participants (n = 153) had received the primary series for COVID-19 vaccination. Mean (SD) time between index SARS-CoV-2 infection and randomization was 17.5 (9.1) months. There was no statistically significant difference in the model-derived severity outcome pooled across the 6 core symptoms at 10 weeks between the NMV/r and PBO/r groups. No statistically significant between-group differences were found at 10 weeks in the Patient Global Impression of Severity or Patient Global Impression of Change scores, summative symptom scores, and change from baseline to 10 weeks in PROMIS fatigue, dyspnea, cognitive function, and physical function measures. Adverse event rates were similar in NMV/r and PBO/r groups and mostly of low grade.

Conclusions and Relevance

The results of this randomized clinical trial showed that a 15-day course of NMV/r in a population of patients with PASC was generally safe but did not demonstrate a significant benefit for improving select PASC symptoms in a mostly vaccinated cohort with protracted symptom duration. Further studies are needed to determine the role of antivirals in the treatment of PASC.

Trial Registration

ClinicalTrials.gov Identifier: NCT05576662.

Characterizing Long COVID in Children and Adolescents

Importance

Most research to understand postacute sequelae of SARS-CoV-2 infection (PASC), or long COVID, has focused on adults, with less known about this complex condition in children. Research is needed to characterize pediatric PASC to enable studies of underlying mechanisms that will guide future treatment.

Objective

To identify the most common prolonged symptoms experienced by children (aged 6 to 17 years) after SARS-CoV-2 infection, how these symptoms differ by age (school-age [6-11 years] vs adolescents [12-17 years]), how they cluster into distinct phenotypes, and what symptoms in combination could be used as an empirically derived index to assist researchers to study the likely presence of PASC.

Design, Setting, and Participants

Multicenter longitudinal observational cohort study with participants recruited from more than 60 US health care and community settings between March 2022 and December 2023, including school-age children and adolescents with and without SARS-CoV-2 infection history.

Exposure

SARS-CoV-2 infection.

Main Outcomes and Measures

PASC and 89 prolonged symptoms across 9 symptom domains.

Results

A total of 898 school-age children (751 with previous SARS-CoV-2 infection [referred to as infected] and 147 without [referred to as uninfected]; mean age, 8.6 years; 49% female; 11% were Black or African American, 34% were Hispanic, Latino, or Spanish, and 60% were White) and 4469 adolescents (3109 infected and 1360 uninfected; mean age, 14.8 years; 48% female; 13% were Black or African American, 21% were Hispanic, Latino, or Spanish, and 73% were White) were included. Median time between first infection and symptom survey was 506 days for school-age children and 556 days for adolescents. In models adjusted for sex and race and ethnicity, 14 symptoms in both school-age children and adolescents were more common in those with SARS-CoV-2 infection history compared with those without infection history, with 4 additional symptoms in school-age children only and 3 in adolescents only. These symptoms affected almost every organ system. Combinations of symptoms most associated with infection history were identified to form a PASC research index for each age group; these indices correlated with poorer overall health and quality of life. The index emphasizes neurocognitive, pain, and gastrointestinal symptoms in school-age children but change or loss in smell or taste, pain, and fatigue/malaise-related symptoms in adolescents. Clustering analyses identified 4 PASC symptom phenotypes in school-age children and 3 in adolescents.

Conclusions and Relevance

This study developed research indices for characterizing PASC in children and adolescents. Symptom patterns were similar but distinguishable between the 2 groups, highlighting the importance of characterizing PASC separately for these age ranges.

Long COVID: a clinical update

Post-COVID-19 condition (also known as long COVID) is generally defined as symptoms persisting for 3 months or more after acute COVID-19. Long COVID can affect multiple organ systems and lead to severe and protracted impairment of function as a result of organ damage. The burden of this disease, both on the individual and on health systems and national economies, is high. In this interdisciplinary Review, with a coauthor with lived experience of severe long COVID, we sought to bring together multiple streams of literature on the epidemiology, pathophysiology (including the hypothesised mechanisms of organ damage), lived experience and clinical manifestations, and clinical investigation and management of long COVID. Although current approaches to long COVID care are largely symptomatic and supportive, recent advances in clinical phenotyping, deep molecular profiling, and biomarker identification might herald a more mechanism-informed and personally tailored approach to clinical care. We also cover the organisation of services for long COVID, approaches to preventing long COVID, and suggestions for future research.

Knowledge Representation and Management in the Age of Long Covid and Large Language Models: a 2022-2023 Survey

OBJECTIVES

To select, present, and summarize cutting edge work in the field of Knowledge Representation and Management (KRM) published in 2022 and 2023.

METHODS

A comprehensive set of KRM-relevant articles published in 2022 and 2023 was retrieved by querying PubMed. Topic modeling with Latent Dirichlet Allocation was used to further refine this query and suggest areas of focus. Selected articles were chosen based on a review of their title and abstract.

RESULTS

An initial set of 8,706 publications were retrieved from PubMed. From these, fifteen papers were ultimately selected matching one of two main themes: KRM for long COVID, and KRM approaches used in combination with generative large language models.

CONCLUSIONS

This survey shows the ongoing development and versatility of KRM approaches, both to improve our understanding of a global health crisis and to augment and evaluate cutting edge technologies from other areas of artificial intelligence.

Determining the societal value of a prospective drug for ME/CFS in Germany

BACKGROUND

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) imposes a substantial societal and economic burden. The aim of this study is to ascertain the optimal level of public research and development (R&D) investment in Germany for a prospective drug, given the pressing need for effective treatments.

METHODS

This study calculates the societal value from a German perspective by integrating health and economic outcomes in the context of public R&D investment for ME/CFS. It considers factors such as direct medical costs, productivity loss, and the effectiveness of a prospective drug.

RESULTS

The anticipated introduction of a prospective drug is estimated to yield a quality-adjusted life year (QALY) gain of approximately 29,000 and a societal value of about €2.6 billion. The optimal R&D investment in Germany is estimated at €676 million, which represents about a quarter of the total investment required to bring a significant drug to market, considering diminishing returns and market constraints. Results were confirmed in the sensitivity analysis.

CONCLUSIONS

The study concludes that a coordinated international approach is imperative to address the funding and market size limitations effectively in developing treatments for ME/CFS and to realize the substantial societal and economic benefits.

Effects of Pycnogenol® in people with post-COVID-19 condition (PYCNOVID): study protocol for a single-center, placebo controlled, quadruple-blind, randomized trial

BACKGROUND

A significant proportion of the global population has been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at some point since the onset of the pandemic. Although most individuals who develop coronavirus disease 2019 (COVID-19) recover without complications, about 6% have persistent symptoms, referred to as post-COVID-19 condition (PCC). Intervention studies investigating treatments that potentially alleviate PCC-related symptoms and thus aim to mitigate the global public health burden and healthcare costs linked to PCC are desperately needed. The PYCNOVID trial investigates the effects of Pycnogenol®, a French maritime pine bark extract with anti-inflammatory and antioxidative properties, versus placebo on patient-reported health status in people with PCC.

METHODS

This is a single-center, placebo-controlled, quadruple blind, randomized trial. We aim to randomly assign 150 individuals with PCC (1:1 ratio) to receive either 200 mg Pycnogenol® or placebo daily for 12 weeks. Randomization is stratified for duration of PCC symptoms (≤ 6 months versus > 6 months) and presence of symptomatic chronic disease(s). The primary endpoint is perceived health status at 12 weeks (EuroQol-Visual Analogue Scale) adjusted for baseline values and stratification factors. Secondary endpoints include change in self-reported PCC symptoms, health-related quality of life, symptoms of depression and anxiety, cognitive function, functional exercise capacity, physical activity measured with accelerometry, and blood biomarkers for endothelial health, inflammation, coagulation, platelet function, and oxidative stress. Investigators, study participants, outcome assessors, and data analysts are blinded regarding the intervention assignment. Individuals with PCC were involved in the design of this study.

DISCUSSION

This is the first trial to investigate the effects of Pycnogenol® versus placebo on patient-reported health status in people with PCC. Should the trial proof clinical effectiveness, Pycnogenol® may serve as a therapeutic approach to mitigate symptoms associated with PCC.

TRIAL REGISTRATION

The study is registered at ClinicalTrials.gov. :NCT05890534, June 6, 2023.

Long COVID management: a mini review of current recommendations and underutilized modalities

Long COVID is a condition that develops in a subset of patients after COVID-19 infection comprising of symptoms of varying severity encompassing multiple organ systems. Currently, long COVID is without consensus on a formal definition, identifiable biomarkers, and validated treatment. Long COVID is expected to be a long-term chronic condition for a subset of patients and is associated with suffering and incapacity. There is an urgent need for clear management guidelines for the primary care provider, who is essential in bridging the gap with more specialized care to improve quality of life and functionality in their patients living with long COVID. The purpose of this mini review is to provide primary care providers with the latest highlights from existing literature regarding the most common long COVID symptoms and current management recommendations. This review also highlights the underutilized interventions of stellate ganglion blocks and low-dose naltrexone, both with well-established safety profiles demonstrated to improve quality of life and functionality for patients suffering with some symptoms of long COVID, and encourages prompt referral to interventional pain management.

Colchicine to reduce coronavirus disease-19-related inflammation and cardiovascular complications in high-risk patients post-acute infection with SARS-COV-2-a study protocol for a randomized controlled trial

BACKGROUND

There is no known effective pharmacological therapy for long COVID, which is characterized by wide-ranging, multisystemic, fluctuating, or relapsing symptoms in a large proportion of survivors of acute COVID. This randomized controlled trial aims to assess the safety and efficacy of an anti-inflammatory agent colchicine, to reduce symptoms among those at high risk of developing long COVID.

METHODS

This multi-centre, parallel arm, 1:1 individual randomized, placebo-controlled, double-blind superiority trial will enrol 350 individuals with persistent post-COVID symptoms. Participants will be randomized to either colchicine 0.5 mg once daily (< 70 kg) or twice daily (≥ 70 kg) or matched placebo for 26 weeks and will be followed up until 52 weeks after randomization. The primary trial objective is to demonstrate the superiority of colchicine over a placebo in improving distance walked in 6 min at 52 weeks from baseline. The secondary objectives are to assess the efficacy of colchicine compared to placebo with respect to lung function, inflammatory markers, constitutional symptoms, and mental health state. In a sub-sample of 100 participants, cardiac biomarkers of myocardial injury and myocardial oedema using MRI will be compared.

DISCUSSION

Persistent inflammatory response following SARS-CoV-19 is one of the postulated pathophysiological mechanisms of long COVID. Colchicine, a low-cost anti-inflammatory agent, acts via multiple inflammatory pathways and has an established safety profile. This trial will generate evidence for an important health priority that can rapidly translate into practice.

TRIAL REGISTRATION

This clinical trial has been registered prospectively on www.

CLINICALTRIALS

gov with registration CTRI/2021/11/038234 dated November 24, 2021.

Exploring the Pathophysiology of Long COVID: The Central Role of Low-Grade Inflammation and Multisystem Involvement

Long COVID (LC), also referred to as Post COVID-19 Condition, Post-Acute Sequelae of SARS-CoV-2 Infection (PASC), and other terms, represents a complex multisystem disease persisting after the acute phase of COVID-19. Characterized by a myriad of symptoms across different organ systems, LC presents significant diagnostic and management challenges. Central to the disorder is the role of low-grade inflammation, a non-classical inflammatory response that contributes to the chronicity and diversity of symptoms observed. This review explores the pathophysiological underpinnings of LC, emphasizing the importance of low-grade inflammation as a core component. By delineating the pathogenetic relationships and clinical manifestations of LC, this article highlights the necessity for an integrated approach that employs both personalized medicine and standardized protocols aimed at mitigating long-term consequences. The insights gained not only enhance our understanding of LC but also inform the development of therapeutic strategies that could be applicable to other chronic conditions with similar pathophysiological features.

Molecular cross-talk between long COVID-19 and Alzheimer's disease

The long COVID (coronavirus disease), a multisystemic condition following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, is one of the widespread problems. Some of its symptoms affect the nervous system and resemble symptoms of Alzheimer's disease (AD)-a neurodegenerative condition caused by the accumulation of amyloid beta and hyperphosphorylation of tau proteins. Multiple studies have found dependence between these two conditions. Patients with Alzheimer's disease have a greater risk of SARS-CoV-2 infection due to increased levels of angiotensin-converting enzyme 2 (ACE2), and the infection itself promotes amyloid beta generation which enhances the risk of AD. Also, the molecular pathways are alike-misregulations in folate-mediated one-carbon metabolism, a deficit of Cq10, and disease-associated microglia. Medical imaging in both of these diseases shows a decrease in the volume of gray matter, global brain size reduction, and hypometabolism in the parahippocampal gyrus, thalamus, and cingulate cortex. In some studies, a similar approach to applied medication can be seen, including the use of amino adamantanes and phenolic compounds of rosemary. The significance of these connections and their possible application in medical practice still needs further study but there is a possibility that they will help to better understand long COVID.

Long COVID syndrome: An unfolding enigma

Post-acute sequelae of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease (COVID-19), called as long COVID syndrome, is a major global public health issue after recovery from COVID-19. The disease occurs in symptomatic patients irrespective of illness severity. The symptoms continue after four wk of recovery from acute illness and persist beyond three months. Risk factors for long COVID include older age, female gender, multiple co-morbidities including diabetes mellitus, prior chronic respiratory illnesses, hospitalized patients with severe disease, especially receiving assisted ventilation, high viral load, reactivation of Epstein Barr (EB) virus and human herpes virus 6 (HH6), circulating auto antibodies against various organs and type I interferon. The prevalence varies from 10 to 20 per cent, and most data have been reported from high-income countries. Any system can get involved in long COVID. The symptoms include fatigue, cognition impairment, cough and dyspnoea, anosmia, hair loss and diarrhoea, among others. While there are no laboratory tests for confirmation of diagnosis, reduced complement C7 complexes at six months, and a two-gene biomarker including FYN and SARS-CoV-2 antisense ribonucleic acid (RNA) are emerging as potentially useful biomarkers for long COVID. There should be no alternative disease to explain various symptoms. Vaccination against SARS-CoV-2 and early use of oral antiviral nirmatrelvir within the first five days in patients with acute mild disease having various risk factors for progression to severe disease help in preventing long COVID. Several clinical trials are underway for the treatment of long COVID and the results of these are eagerly awaited. Physical and mental rehabilitation at home, at community level or in the hospital setting as appropriate is essential in patients with long COVID.

Low-dose naltrexone for post-COVID fatigue syndrome: a study protocol for a double-blind, randomised trial in British Columbia

INTRODUCTION

A significant proportion of individuals suffering from post COVID-19 condition (PCC, also known as long COVID) can present with persistent, disabling fatigue similar to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-viral fatigue syndromes. There remains no clear pharmacological therapy for patients with this subtype of PCC, which can be referred to as post-COVID fatigue syndrome (PCFS). A low dose of the opioid antagonist naltrexone (ie, low-dose naltrexone (LDN)) has emerged as an off-label treatment for treating fatigue and other symptoms in PCC. However, only small, non-controlled studies have assessed LDN in PCC, so randomised trials are urgently required.

METHODS AND ANALYSIS

A prospective, randomised, double-blind, parallel arm, placebo-controlled phase II trial will be performed to assess the efficacy of LDN for improving fatigue in PCFS. The trial will be decentralised and open to eligible individuals throughout the Canadian province of British Columbia (BC). Participants will be recruited through the province-wide Post-COVID-19 Interdisciplinary Clinical Care Network (PC-ICCN) and research volunteer platform (REACH BC). Eligible participants will be 19-69 years old, have had a confirmed or physician-suspected SARS-CoV-2 infection at least 3 months prior and meet clinical criteria for PCFS adapted from the Institute of Medicine ME/CFS criteria. Individuals who are taking opioid medications, have a history of ME/CFS prior to COVID-19 or history of significant liver disease will be excluded. Participants will be randomised to an LDN intervention arm (n=80) or placebo arm (n=80). Participants in each arm will be prescribed identical capsules starting at 1 mg daily and follow a prespecified schedule for up-titration to 4.5 mg daily or the maximum tolerated dose. The trial will be conducted over 16 weeks, with assessments at baseline, 6, 12 and 16 weeks. The primary outcome will be fatigue severity at 16 weeks evaluated by the Fatigue Severity Scale. Secondary outcomes will include pain Visual Analogue Scale score, overall symptom severity as measured by the Patient Phenotyping Questionnaire Short Form, 7-day step count and health-related quality of life measured by the EuroQol 5-Dimension questionnaire.

ETHICS AND DISSEMINATION

The trial has been authorised by Health Canada and approved by The University of British Columbia/Children's and Women's Health Centre of British Columbia Research Ethics Board. On completion, findings will be disseminated to patients, caregivers and clinicians through engagement activities within existing PCC and ME/CFS networks. Results will be published in academic journals and presented at conferences.

TRIAL REGISTRATION NUMBER

NCT05430152.

Current landscape of long COVID clinical trials

Long COVID was reported as a multi-systemic condition after the infection of SARS-CoV-2, and more than 65 million people are suffering from this disease. It has been noted that around 10% of severe SARS-CoV-2 infected individuals are suffering from the enduring effects of long COVID. The symptoms of long COVID have also been noted in several mild or asymptomatic SARS-CoV-2 infected individuals. While limited reports on clinical trials investigating new therapeutics for long COVID exist, there is an abundance of scattered information available regarding these trials. This review explores the extensive literature search, and complete clinical trial database search to map the current status of long COVID clinical trials worldwide. The study listed about 110 long COVID clinical trials. In addition to conducting extensive long COVID clinical trials, we have comprehensively presented an overview of the condition, its symptoms, notable manifestations, associated clinical trials, the unique challenges it poses, and our recommendations for addressing long COVID.

Blueprint of differentially expressed genes reveals the dynamic gene expression landscape and the gender biases in long COVID

BACKGROUND

Long COVID has appeared as a significant global health issue and is an extra burden to the healthcare system. It affects a considerable number of people throughout the globe. However, substantial research gaps have been noted in understanding the mechanism and genomic landscape during the long COVID infection. A study has aimed to identify the differentially expressed genes (DEGs) in long COVID patients to fill the gap.

METHODS

We used the RNA-seq GEO dataset acquired through the GPL20301 Illumina HiSeq 4000 platform. The dataset contains 36 human samples derived from PBMC (Peripheral blood mononuclear cells). Thirty-six human samples contain 13 non-long COVID individuals' samples and 23 long COVID individuals' samples, considered the first direction analysis. Here, we performed two-direction analyses. In the second direction analysis, we divided the dataset gender-wise into four groups: the non-long COVID male group, the long COVID male group, the non-long COVID female group, and the long COVID female group.

RESULTS

In the first analysis, we found no gene expression. In the second analysis, we identified 250 DEGs. During the DEG profile analysis of the non-long COVID male group and the long COVID male group, we found three upregulated genes: IGHG2, IGHG4, and MIR8071-2. Similarly, the analysis of the non-long COVID female group and the long COVID female group reveals eight top-ranking genes. It also indicates the gender biases of differentially expressed genes among long COVID individuals. We found several DEGs involved in PPI and co-expression network formation. Similarly, cluster enrichment and gene list enrichment analysis were performed, suggesting several genes are involved in different biological pathways or processes.

CONCLUSIONS

This study will help better understand the gene expression landscape in long COVID. However, it might help the discovery and development of therapeutics for long COVID.

Management of cognitive impairment associated with post-COVID-19 syndrome: recommendations for primary care

Introduction: Although post-COVID-19 syndrome (PCS) with cognitive impairment is increasingly encountered in primary care, evidence-based recommendations for its appropriate management are lacking. Methods: A systematic literature search evaluating the diagnosis and treatment of cognitive impairment associated with PCS was conducted. Practical recommendations for the management of PCS-associated cognitive impairment in primary care are summarized, based on an evaluation of pharmacological plausibility and clinical applications. Results: Currently, the pathology of cognitive impairment associated with PCS remains unclear with no high-quality data to support targeted interventions. Existing treatment approaches are directed towards symptom relief where counseling on the chronicity of the disease and regular reassessments at 4- to 8-week intervals is considered reasonable. Patients should be informed and encouraged to adopt a healthy lifestyle that centers around balanced nutrition and appropriate physical activities. They may also benefit from the intake of vitamins, micronutrients, and probiotics. The administration of Ginkgo biloba extract could offer a safe and potentially beneficial treatment option. Other non-pharmacological measures include physiotherapy, digitally supported cognitive training, and, if indicated, ergotherapy or speech therapy. In most patients, symptoms improve within 8 weeks. If serious, ambiguous, or when new symptoms occur, specialized diagnostic measures such as comprehensive neurocognitive testing or neuroimaging should be initiated. Very few patients would require inpatient rehabilitation. Conclusion: PCS with cognitive impairment is a debilitating condition that could affect daily functioning and reduce work productivity. Management in primary care should adopt a multidisciplinary approach, centering around physical, cognitive, and pharmacological therapies.

Impact of vortioxetine on psychosocial functioning moderated by symptoms of fatigue in post-COVID-19 condition: a secondary analysis

INTRODUCTION

Fatigue is a prominent symptom in post-COVID condition (PCC) sequelae, termed "long COVID." Herein, we aim to ascertain the effect of fatigue on psychosocial function in persons living with PCC.

METHODS

This post hoc analysis evaluated the effects of vortioxetine on measures of fatigue as assessed by the Fatigue Severity Scale (FSS) in psychosocial function as measured by the Sheehan Disability Scale (SDS) in persons with PCC. We also evaluated the change in FSS on psychosocial functioning as measured by the Sheehan Disability Scale (SDS). This post hoc analysis obtained data from a recently published placebo-controlled study evaluating vortioxetine's effect on objective cognitive functions in persons living with PCC.

RESULTS

One hundred forty-four participants meeting World Health Organization (WHO) criteria for PCC were included in this analysis. At the end of 8 weeks of vortioxetine treatment, significant improvement of all domains was observed for psychosocial functioning. There was a significant between-group difference at treatment endpoint in the family, social, and work SDS subcategories (p < 0.001). There was a statistically significant interaction effect between the treatment condition time point and FSS effect on the SDS social (χ2 = 10.640, p = 0.014) and work (χ2 = 9.342, p = 0.025) categories but a statistically insignificant effect on the family categories ((χ2 = 5.201, p = 0.158)).

DISCUSSION

This post hoc analysis suggests that vortioxetine treatment significantly improves psychosocial function in persons with PCC. Our results also indicate that the improvement in psychosocial function was significantly mediated by improvement in measures of fatigue. Our results provide empirical support for recommendations to identify therapeutics for fatigue in persons living with PCC with a broader aim to improve psychosocial function in this common and severely impaired population.

Large-scale phenotyping of patients with long COVID post-hospitalization reveals mechanistic subtypes of disease

One in ten severe acute respiratory syndrome coronavirus 2 infections result in prolonged symptoms termed long coronavirus disease (COVID), yet disease phenotypes and mechanisms are poorly understood1. Here we profiled 368 plasma proteins in 657 participants ≥3 months following hospitalization. Of these, 426 had at least one long COVID symptom and 233 had fully recovered. Elevated markers of myeloid inflammation and complement activation were associated with long COVID. IL-1R2, MATN2 and COLEC12 were associated with cardiorespiratory symptoms, fatigue and anxiety/depression; MATN2, CSF3 and C1QA were elevated in gastrointestinal symptoms and C1QA was elevated in cognitive impairment. Additional markers of alterations in nerve tissue repair (SPON-1 and NFASC) were elevated in those with cognitive impairment and SCG3, suggestive of brain-gut axis disturbance, was elevated in gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G (IgG) was persistently elevated in some individuals with long COVID, but virus was not detected in sputum. Analysis of inflammatory markers in nasal fluids showed no association with symptoms. Our study aimed to understand inflammatory processes that underlie long COVID and was not designed for biomarker discovery. Our findings suggest that specific inflammatory pathways related to tissue damage are implicated in subtypes of long COVID, which might be targeted in future therapeutic trials.

Complement dysregulation is a prevalent and therapeutically amenable feature of long COVID

BACKGROUND

Long COVID encompasses a heterogeneous set of ongoing symptoms that affect many individuals after recovery from infection with SARS-CoV-2. The underlying biological mechanisms nonetheless remain obscure, precluding accurate diagnosis and effective intervention. Complement dysregulation is a hallmark of acute COVID-19 but has not been investigated as a potential determinant of long COVID.

METHODS

We quantified a series of complement proteins, including markers of activation and regulation, in plasma samples from healthy convalescent individuals with a confirmed history of infection with SARS-CoV-2 and age/ethnicity/sex/infection/vaccine-matched patients with long COVID.

FINDINGS

Markers of classical (C1s-C1INH complex), alternative (Ba, iC3b), and terminal pathway (C5a, TCC) activation were significantly elevated in patients with long COVID. These markers in combination had a receiver operating characteristic predictive power of 0.794. Other complement proteins and regulators were also quantitatively different between healthy convalescent individuals and patients with long COVID. Generalized linear modeling further revealed that a clinically tractable combination of just four of these markers, namely the activation fragments iC3b, TCC, Ba, and C5a, had a predictive power of 0.785.

CONCLUSIONS

These findings suggest that complement biomarkers could facilitate the diagnosis of long COVID and further suggest that currently available inhibitors of complement activation could be used to treat long COVID.

FUNDING

This work was funded by the National Institute for Health Research (COV-LT2-0041), the PolyBio Research Foundation, and the UK Dementia Research Institute.

Baseline Characteristics in the Remote Diet Intervention to REduce long-COVID Symptoms Trial (ReDIRECT)

Background

The persistence of symptoms for ≥12 weeks after a COVID-19 infection is known as Long COVID (LC), a condition with unclear pathophysiology and no proven treatments to date. Living with obesity is a risk factor for LC and has symptoms which may overlap with and aggravate LC.

Methods

ReDIRECT is a remotely delivered trial assessing whether weight management can reduce LC symptoms. We recruited people with LC and BMI >27kg/m 2. The intervention was delivered remotely by dietitians, with online data collection (medical and dietary history, COVID-19 infection and vaccination, body composition, LC history/symptoms, blood pressure, quality of life, sociodemographic data). Participants self-selected the dominant LC symptoms they most wanted to improve from the intervention.

Results

Participants (n=234) in England (64%) and Scotland (30%) were mainly women (85%) of white ethnicity (90%), with 13% living in the 20% most deprived areas, a mean age of 46 (SD10) years, and median BMI of 35kg/m 2 (IQR 32-40). Before starting the study, 30% reported more than one COVID-19 infection (82% confirmed with one or more positive tests). LC Diagnosis was mainly by GPs (71%), other healthcare professionals (9%), or self-diagnosed (21%). The median total number of symptoms was 6 (IQR 4-8). Self-selected dominant LC symptoms included fatigue (54%), breathlessness (16%), pain (12%), anxiety/depression (1%) and "other" (17%). At baseline, 82% were taking medication, 57% reported 1+ other medical conditions. Quality of life was poor; 20% were on long-term sick leave or reduced working hours. Most (92%) reported having gained weight since contracting COVID-19 (median weight change +11.5 kg, range -11.5 to +45.3 kg).

Conclusions

Symptoms linked to LC and overweight are diverse and complex. Remote trial delivery enabled rapid recruitment across the UK yet certain groups (e.g. men and those from ethnic minority groups) were under-represented.

Trial registration

ISRCTN registry ( ISRCTN12595520, 25/11/2021).

Potential Beneficial Effects of Naringin and Naringenin on Long COVID-A Review of the Literature

Coronavirus disease 2019 (COVID-19) caused a severe epidemic due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Recent studies have found that patients do not completely recover from acute infections, but instead, suffer from a variety of post-acute sequelae of SARS-CoV-2 infection, known as long COVID. The effects of long COVID can be far-reaching, with a duration of up to six months and a range of symptoms such as cognitive dysfunction, immune dysregulation, microbiota dysbiosis, myalgic encephalomyelitis/chronic fatigue syndrome, myocarditis, pulmonary fibrosis, cough, diabetes, pain, reproductive dysfunction, and thrombus formation. However, recent studies have shown that naringenin and naringin have palliative effects on various COVID-19 sequelae. Flavonoids such as naringin and naringenin, commonly found in fruits and vegetables, have various positive effects, including reducing inflammation, preventing viral infections, and providing antioxidants. This article discusses the molecular mechanisms and clinical effects of naringin and naringenin on treating the above diseases. It proposes them as potential drugs for the treatment of long COVID, and it can be inferred that naringin and naringenin exhibit potential as extended long COVID medications, in the future likely serving as nutraceuticals or clinical supplements for the comprehensive alleviation of the various manifestations of COVID-19 complications.

Cardiovascular effects of the post-COVID-19 condition

Throughout the COVID-19 pandemic, the new clinical entity of the post-COVID-19 condition, defined as a multisystemic condition of persistent symptoms following resolution of an acute severe acute respiratory syndrome coronavirus 2 infection, has emerged as an important area of clinical focus. While this syndrome spans multiple organ systems, cardiovascular complications are often the most prominent features. These include, but are not limited to, myocardial injury, heart failure, arrhythmias, vascular injury/thrombosis and dysautonomia. As the number of individuals with the post-COVID-19 condition continues to climb and overwhelm medical systems, summarizing existing information and knowledge gaps in the complex cardiovascular effects of the post-COVID-19 condition has become critical for patient care. In this Review, we explore the current state of knowledge of the post-COVID-19 condition and identify areas where additional research is warranted. This will provide a framework for better understanding the cardiovascular manifestations of the post-COVID-19 condition with a focus on pathophysiology, diagnosis and management.

Longitudinal Progression of Patients with Long COVID Treated in a Post-COVID Clinic: A Cross-Sectional Survey

BACKGROUND

In addition to the morbidity and mortality associated with acute infection, COVID-19 has been associated with persistent symptoms (>30 days), often referred to as Long COVID (LC). LC symptoms often cluster into phenotypes, resembling conditions such as fibromyalgia, postural orthostatic tachycardiac syndrome (POTS), and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). LC clinics have been established to best address the needs of LC patients and continuity of care. We developed a cross-sectional survey to assess treatment response through our LC Clinic (LCC).

METHODS

A 25-question survey (1-10 Likert scale) was expert- and content-validated by LCC clinicians, patients, and patient advocates. The survey assessed LC symptoms and the helpfulness of different interventions, including medications and supplements. A total of 852 LCC patients were asked to complete the survey, with 536 (62.9%) responding.

RESULTS

The mean time from associated COVID-19 infection to survey completion was 23.2 ± 6.4 months. The mean age of responders was 52.3 ± 14.1 (63% females). Self-reported symptoms were all significantly improved (P < .001) from the initial visit to the LCC (baseline) to the time of the follow-up survey. However, only 4.5% (24/536) of patients rated all symptoms low (1-2) at the time of the survey, indicating low levels of full recovery in our cohort. The patients rated numerous interventions as being helpful, including low-dose naltrexone (45/77; 58%), vagal nerve stimulation (18/34; 53%), and fisetin (28/44; 64%).

CONCLUSIONS

Patients report general improvements in symptoms following the initial LCC visit, but complete recovery rates remain low at 23.2 ± 6.4 months.

Reducing sick leave, improving work ability, and quality of life in patients with mild to moderate Long COVID through psychosocial, physiotherapeutic, and nutritive supportive digital intervention (MiLoCoDaS): study protocol for a randomized controlled trial

BACKGROUND

Following SARS-CoV-2 infection, a relevant proportion of patients suffer from persistent or recurring sequela, even after initially mild primary illness. Many patients experience exhaustion and fatigue, rendering them incapable of working. Long COVID exerts a substantial burden on society and the healthcare system: at least 65 million people are currently affected worldwide. The underlying pathobiology is a complex derangement in several organ systems. To date, causal pharmaceutical therapies remain elusive. Waiting lists for specialist care are long. Rapidly scalable digital interventions offering support for the frequent subgroup of patients with mild to moderate impairment from Long COVID are urgently needed. The MiLoCoDaS study compares three intensities of a potentially rapidly scalable digital intervention aiming to accelerate recovery. The overall objective is to figure out if there is a difference in the effect sizes between these modalities.

METHODS

The online intervention uses a learning platform (LMS, TYPO3 framework) comprising 12 sessions of medical, psychological, physiotherapeutic, and nutritional content. The three modalities differ as follows: patient information only (sham intervention, control), information plus interactive digital workbook including practical exercises (digital intervention), and the digital workbook augmented by once-weekly online seminars and discussion groups (person and peer-contact). Eligible patients are 18-67 years old satisfying Long COVID diagnostic criteria. Patients are recruited through primary care physicians and randomly allocated. The primary endpoint is the number of sick leave days during the 6-month observation period; secondary endpoints are patient-reported symptoms, quality of life, and work ability. The study size provides a power of 80% at a type I error of < 0.05 to show an effect size of Cohen = 0.3 between the augmented and the sham intervention (N = 152 per arm, total accounting for attrition N = 600).

DISCUSSION

If one of the two interventions is superior to providing information alone, MiLoCoDaS would provide the starting point for a rapidly scalable digital intervention for the frequent and currently underserved patient group with mild to moderate impairment from Long COVID. Several caveats pertain to the heterogeneity of Long COVID manifestation and duration prior to inclusion. It is conceivable that the possible effect of the intervention may differ across subgroups. Therefore, a priori defined secondary analysis will be conducted.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS) DRKS00028964. Registered on 24 August 2022.

Cardiovascular autonomic dysfunction in "Long COVID": pathophysiology, heart rate variability, and inflammatory markers

Long COVID is characterized by persistent signs and symptoms that continue or develop for more than 4 weeks after acute COVID-19 infection. Patients with Long COVID experience a cardiovascular autonomic imbalance known as dysautonomia. However, the underlying autonomic pathophysiological mechanisms behind this remain unclear. Current hypotheses include neurotropism, cytokine storms, and inflammatory persistence. Certain immunological factors indicate autoimmune dysfunction, which can be used to identify patients at a higher risk of Long COVID. Heart rate variability can indicate autonomic imbalances in individuals suffering from Long COVID, and measurement is a non-invasive and low-cost method for assessing cardiovascular autonomic modulation. Additionally, biochemical inflammatory markers are used for diagnosing and monitoring Long COVID. These inflammatory markers can be used to improve the understanding of the mechanisms driving the inflammatory response and its effects on the sympathetic and parasympathetic pathways of the autonomic nervous system. Autonomic imbalances in patients with Long COVID may result in lower heart rate variability, impaired vagal activity, and substantial sympathovagal imbalance. New research on this subject must be encouraged to enhance the understanding of the long-term risks that cardiovascular autonomic imbalances can cause in individuals with Long COVID.

Post-COVID cognitive dysfunction: current status and research recommendations for high risk population

Post-COVID cognitive dysfunction (PCCD) is a condition in which patients with a history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, usually three months from the onset, exhibit subsequent cognitive impairment in various cognitive domains, and cannot be explained by an alternative diagnosis. While our knowledge of the risk factors and management strategy of PCCD is still incomplete, it is necessary to integrate current epidemiology, diagnosis and treatment evidence, and form consensus criteria to better understand this disease to improve disease management. Identifying the risk factors and vulnerable population of PCCD and providing reliable strategies for effective prevention and management is urgently needed. In this paper, we reviewed epidemiology, diagnostic markers, risk factors and available treatments on the disease, formed research recommendation framework for vulnerable population, under the background of post-COVID period.

Intravenous immunoglobulin as a potential treatment for long COVID

INTRODUCTION

On 31 July 2023, the United States Department of Health and Human Services announced the formation of the Office of Long COVID Research and Practice and the United States National Institutes of Health (NIH) opened enrollment for the therapeutic arm of the RECOVER initiative, a prospective, randomized study to evaluate new treatment options for long coronavirus disease 2019 (long COVID).

AREAS COVERED

One of the first drugs to be studied in this nationwide initiative is intravenous immunoglobulin (IVIG), which will be a treatment option for subjects enrolled in RECOVER-AUTO, a randomized trial to investigate therapeutic strategies for autonomic dysfunction related to long COVID.

EXPERT OPINION

IVIG is a mixture of human antibodies (human immunoglobulin) that has been widely used to treat a variety of diseases, including immune thrombocytopenia purpura, Kawasaki disease, chronic inflammatory demyelinating polyneuropathy, and certain infections such as influenza, human immunodeficiency virus, and measles. However, the role of IVIG in the treatment of post-COVID-19 conditions is uncertain. This manuscript examines what is known about IVIG in the treatment of long COVID and explores how this therapeutic agent may be used in the future to address this condition.