Post-COVID-19 Condition

Long COVID and gut candidiasis: What is the existing relationship?

Since the beginning of the coronavirus disease (COVID) 2019 pandemic, thousands of articles on the topic have been published, and although there is a growing trend of research on another associated condition, long coronavirus disease, important points still remain to be clarified in this respect. Robust evidence has suggested a relevant link between new clinical discoveries and molecular mechanisms that could be associated with the manifestations of different signs and symptoms involving cases of long COVID. However, one of the existing gaps that requires further investigation concerns a possible relationship between gut candidiasis and long COVID. While recent studies also suggest an interplay between the occurrence of these two conditions, it is not yet fully clear how this may happen, as well as the specifics regarding the possible pathophysiological mechanisms involved. In this connection and with the advent of a potential strengthening of the body of evidence supporting the hypothesis of a link between gut candidiasis and long COVID, a better understanding of the clinical presentation, pathophysiology and clinical management of such a relationship should be essential and useful for both, additional advances towards more targeted research and appropriate case management. Knowing more about the signs, symptoms, and complications associated with cases of long COVID is essential in order to more effectively mitigate the related burden and provide a higher quality of care and life for the affected population. In light of this and the need for better outcomes, here we review and discuss the content on different aspects of long COVID, including its pathophysiology and the existing evidence of a potential relationship between such a condition and gut candidiasis, as well as suggest propositions for future related research.

[Fatigue after COVID-19 disease associated with depression and anxiety in insured persons from healthcare and social professions]

BACKGROUND

Fatigue is one of the most frequent symptoms in post-COVID syndrome (PCS) patients and describes a long-term feeling of tiredness and exhaustion. Frequently, it follows an infection or is a component of depressive symptoms. But fatigue itself is also a risk to mental health like other chronic conditions. The objective of this paper was to analyse the relationship between fatigue and depression/anxiety and the differences between PCS patients and fully recovered COVID-19 cases.

METHODS

In a longitudinal study with three measurement points, insured members of the Statutory Accident Insurance and Prevention in the Health and Welfare Service with a SARS-CoV‑2 infection in 2020 were asked about fatigue, depression/anxiety and persisting COVID-19 symptoms. To analyse the longitudinal effects of the two variables, a cross-lagged panel model was applied.

RESULTS

In the present sample (n = 860), a proportion of 68.7% to 75.1% of people was suffering from PCS. The results showed a model fit of R2 = 61.49% and all effects were significant, but the cross-lagged effects were not significantly different from each other. If stratified according to whether PCS symptoms were present, the cross-lagged effects weakened in both groups, while the effects of fatigue on depression and anxiety only remained in the group of those affected by PCS.

DISCUSSION

The results show a relationship in both directions between fatigue and depression/anxiety. PCS patients can benefit from psychotherapeutic treatment to tackle fatigue and prevent depression and anxiety.

Symptom Persistence Following COVID-19 Infection among an Indigenous Community Residing in the Isthmus of Tehuantepec, Oaxaca, Mexico

Introduction/Objectives: Several studies have documented the development and persistence of symptoms related to COVID-19 and its secondary complications up to 12 months after the infection. We aimed to identify the medical complications following COVID-19 infection in the Indigenous Zapotec population of the Isthmus of Tehuantepec region in Oaxaca, Mexico. Methods: This is a cross-sectional analytical study that included 90 Indigenous Zapotec participants (30 males and 60 females) from the Tehuantepec region, Oaxaca, Mexico, who had an infectious process due to SARS-CoV-2. Sociodemographic and clinical data were identified through questionnaires. Results: Among the 201 participants, 90 individuals (66.7% women, 33.3% men) had contracted COVID-19. Out of these, 61 individuals reported persistent symptoms post-infection, with a mean symptom duration of 13.87 months. The results show significant variations in symptom duration based on age, marital status, educational attainment, vaccination status, and blood group. The most commonly reported symptoms included a dry cough, fever, myalgia, fatigue, headache, and depressive symptoms. Conclusions: This study highlights the post-COVID-19 symptoms and their prevalence within a specific sample of the Indigenous Zapotec population in Oaxaca, along with the sociodemographic and clinical factors influencing the duration of these symptoms. It underscores the necessity of personalized recovery strategies and highlights the critical role of vaccination in mitigating the long-term impacts of SARS-CoV-2.

Lipid-conjugated nucleoside monophosphate and monophosphonate prodrugs: A versatile drug delivery paradigm

Integrating lipid conjugation strategies into the design of nucleoside monophosphate and monophosphonate prodrugs is a well-established approach for discovering potential therapeutics. The unique prodrug design endows nucleoside analogues with strong lipophilicity and structures resembling lysoglycerophospholipids, which improve cellular uptake, oral bioavailability and pharmacological activity. In addition, the metabolic stability, pharmacological activity, pharmacokinetic profiles and biodistribution of lipid prodrugs can be finely optimized by adding biostable caps, incorporating transporter-targeted groups, inserting stimulus-responsive bonds, adjusting chain lengths, and applying proper isosteric replacements. This review summarizes recent advances in the structural features and application fields of lipid-conjugated nucleoside monophosphate and monophosphonate prodrugs. This collection provides deep insights into the increasing repertoire of lipid prodrug development strategies and offers design inspirations for medicinal chemists for the development of novel chemotherapeutic agents.

New-onset obstructive airway disease following COVID-19: a multicenter retrospective cohort study

BACKGROUND

The study assessed the association between COVID-19 and new-onset obstructive airway diseases, including asthma, chronic obstructive pulmonary disease, and bronchiectasis among vaccinated individuals recovering from COVID-19 during the Omicron wave.

METHODS

This multicenter retrospective cohort study comprised 549,606 individuals from the U.S. Collaborative Network of TriNetX database, from January 8, 2022, to January 17, 2024. The hazard of new-onset obstructive airway diseases between COVID-19 and no-COVID-19 groups were compared following propensity score matching using the Kaplan-Meier method and Cox proportional hazards model.

RESULTS

After propensity score matching, each group contained 274,803 participants. Patients with COVID-19 exhibited a higher risk of developing new-onset asthma than that of individuals without COVID-19 (adjusted hazard ratio (aHR), 1.27; 95% CI, 1.22-1.33; p < 0.001). Stratified analyses by age, SARS-CoV-2 variant, vaccination status, and infection status consistently supported this association. Non-hospitalized individuals with COVID-19 demonstrated a higher risk of new-onset asthma (aHR, 1.27; 95% CI, 1.22-1.33; p < 0.001); however, no significant differences were observed in hospitalized and critically ill groups. The study also identified an increased risk of subsequent bronchiectasis following COVID-19 (aHR, 1.30; 95% CI, 1.13-1.50; p < 0.001). In contrast, there was no significant difference in the hazard of chronic obstructive pulmonary disease between the groups (aHR, 1.00; 95% CI, 0.95-1.06; p = 0.994).

CONCLUSION

This study offers convincing evidence of the association between COVID-19 and the subsequent onset of asthma and bronchiectasis. It underscores the need for a multidisciplinary approach to post-COVID-19 care, with a particular focus on respiratory health.

Tracking cognitive trajectories in older survivors of COVID-19 up to 2.5 years post-infection

Emerging evidence suggests that neurological and other post-acute sequelae of COVID-19 can persist beyond or develop following SARS-CoV-2 infection. However, the long-term trajectories of cognitive change after a COVID-19 infection remain unclear. Here we investigated cognitive changes over a period of 2.5 years among 1,245 individuals aged 60 years or older who survived infection with the original SARS-CoV-2 strain in Wuhan, China, and 358 uninfected spouses. We show that the overall incidence of cognitive impairment among older COVID-19 survivors was 19.1% at 2.5 years after infection and hospitalization, evaluated using the Telephone Interview for Cognitive Status-40. Cognitive decline primarily manifested in individuals with severe COVID-19 during the initial year of infection, after which the rate of decline decelerated. Severe COVID-19, cognitive impairment at 6 months and hypertension were associated with long-term cognitive decline. These findings reveal the long-term cognitive trajectory of the disease and underscore the importance of post-infection cognitive care for COVID-19 survivors.

COVID-19 is associated with changes in brain function and structure: A multimodal meta-analysis of neuroimaging studies

The actual role of coronavirus disease 2019 (COVID-19) in brain damage has been increasingly reported, necessitating a meta-analysis to collate and summarize the inconsistent findings from functional imaging and voxel-based morphometry (VBM) studies. A comprehensive voxel-wise meta-analysis of the whole brain was conducted to identify alterations in functional activity and gray matter volume (GMV) between COVID-19 patients and healthy controls (HCs) by using Seed-based d Mapping software. We included 15 functional imaging studies (484 patients with COVID-19, 534 HCs) and 9 VBM studies (449 patients with COVID-19, 388 HCs) in the analysis. Overall, patients with COVID-19 exhibited decreased functional activity in the right superior temporal gyrus (STG) (extending to the right middle and inferior temporal gyrus, insula, and temporal pole [TP]), left insula, right orbitofrontal cortex (OFC) (extending to the right olfactory cortex), and left cerebellum compared to HCs. For VBM, patients with COVID-19, relative to HCs, showed decreased GMV in the bilateral anterior cingulate cortex/medial prefrontal cortex (extending to the bilateral OFC), and left cerebellum, and increased GMV in the bilateral amygdala (extending to the bilateral hippocampus, STG, TP, MTG, and right striatum). Moreover, overlapping analysis revealed that patients with COVID-19 exhibited both decreased functional activity and increased GMV in the right TP (extending to the right STG). The multimodal meta-analysis suggests that brain changes of function and structure in the temporal lobe, OFC and cerebellum, and functional or structural alterations in the insula and the limbic system in COVID-19. These findings contribute to a better understanding of the pathophysiology of brain alterations in COVID-19. SIGNIFICANCE STATEMENT: This first large-scale multimodal meta-analysis collates existing neuroimaging studies and provides voxel-wise functional and structural whole-brain abnormalities in COVID-19. Findings of this meta-analysis provide valuable insights into the dynamic brain changes (from infection to recovery) and offer further explanations for the pathophysiological basis of brain alterations in COVID-19.

Characteristics of Patients with Persistent COVID-19 Symptoms and Unscheduled Return Visits to a Centre for COVID-19 Evaluation

Background: This retrospective study aimed to evaluate the characteristics of patients with long COVID syndrome. Methods: This study included 457 adults who had at least one persistent symptom after COVID-19 infection. Results: The median time interval between the last SARS-CoV-2 infection and emergency room presentation was 3 months. Older patients had comorbidities (61.7 vs. 44.9 years, p < 0.0001), moderate or severe forms of COVID-19 (61.2 vs. 50.9 years, p < 0.0001), and respiratory symptoms (56.1 vs. 52.0 years, p = 0.0027). Non-vaccinated patients were older than vaccinated patients (56.0 vs. 51.5 years, p = 0.0008) and had residual lung abnormalities following COVID-19 infection (51.5% vs. 36.8%, p < 0.003). The time interval between the last SARS-CoV-2 infection and the hospital evaluation was shorter for vaccinated patients (3.2 vs. 3.9 months, p < 0.0001) and those with mild forms (3.3 vs. 4.12 months, p = 0.0001) versus non-vaccinated individuals. After the last SARS-CoV-2 infection, 107 patients developed impaired fasting glucose, impaired glucose tolerance, or diabetes mellitus, being patients with already known chronic diseases (p = 0.0002), or hypertension (p = 0.001). Conclusions: Our study pointed out the heterogeneity of symptoms following COVID-19, and they are associated with age, vaccination status, or severity of SARS-CoV-2 infection.

Adult Outpatients with Long COVID Infected with SARS-CoV-2 Omicron Variant. Part 1: Oral Microbiota Alterations

BACKGROUND

Many individuals experience long COVID after SARS-CoV-2 infection. As microbiota can influence health, it may change with COVID-19. This study investigated differences in oral microbiota between COVID-19 patients with and without long COVID.

METHODS

Based on a prospective follow-up investigation, this nested case-control study evaluated the differences in oral microbiota in individuals with and without long COVID (Symptomatic and Asymptomatic groups), which were assessed by 16S rRNA sequencing on tongue coating samples. A predictive model was established using machine learning based on specific differential microbial communities.

RESULTS

One-hundred-and-eight patients were included (n=54 Symptomatic group). The Symptomatic group had higher Alpha diversity indices (observed_otus, Chao1, Shannon, and Simpson indices), differences in microbial composition (Beta diversity), and microbial dysbiosis with increased diversity and relative abundance of pathogenic bacteria. Marker bacteria (c__Campylobacterota, o__Coriobacteriales, o__Pseudomonadales, and o__Campylobacterales) were associated with long COVID by linear discriminant analysis effect size and receiver operating characteristic curves (AUC 0.821).

CONCLUSION

There were distinct variations in oral microbiota between COVID-19 patients with and without long COVID. Changes in oral microbiota may indicate long COVID.

Higher intraindividual variability of body mass index is associated with elevated risk of COVID-19 related hospitalization and post-COVID conditions

BACKGROUND

Cardiometabolic diseases are risk factors for COVID-19 severity. The extent that cardiometabolic health represents a modifiable factor to mitigate the short- and long-term consequences from SARS-CoV-2 remains unclear. Our objective was to evaluate the associations between intraindividual variability of cardiometabolic health indicators and COVID-19 related hospitalizations and post-COVID conditions (PCC) among a relatively healthy population.

METHODS

This retrospective, multi-site cohort study was a post-hoc analysis among individuals with cardiometabolic health data collected during routine blood donation visits in 24 US states (2009-2018) and who responded to COVID-19 questionnaires (2021-2023). Intraindividual variability of blood pressure (systolic, diastolic), total circulating cholesterol, and body mass index (BMI) were defined as the coefficient of variation (CV) across all available donation timepoints (ranging from 3 to 74); participants were categorized into CV quartiles. Associations were evaluated by multivariable binomial regressions.

RESULTS

Overall, 3344 participants provided 42,090 donations (median 9 [IQR 5, 17]). The median age was 48 years (38, 56) at the first study donation. 1.2% (N = 40) were hospitalized due to COVID-19 and 15.5% (N = 519) had PCC. Higher BMI variability was associated with greater risk of COVID-19 hospitalization (4th quartile aRR 4.15 [95% CI 1.31, 13.11], p = 0.02; 3rd quartile aRR 3.41 [95% CI 1.09, 10.69], p = 0.04). Participants with higher variability of BMI had greater risk of PCC (4th quartile aRR 1.29 [95% CI 1.02, 1.64]; p = 0.04). Intraindividual variability of blood pressure (systolic, diastolic) and total circulating cholesterol were not associated with COVID-19 hospitalization or PCC risk (all p > 0.05). From causal mediation analysis, the association between the highest quartiles of BMI variability and PCC was not mediated by hospitalization (p > 0.05).

CONCLUSIONS

Higher intraindividual variability of BMI was associated with COVID-19 hospitalization and PCC risk. Our findings underscore the need for further elucidating mechanisms that explain these associations and importance for consistent maintenance of body weight.

The faces of Long-COVID: interplay of symptom burden with socioeconomic, behavioral and healthcare factors

AIMS

The long-term effects of COVID-19 (Long COVID) include 19 symptoms ranging from mild to debilitating. We examined multidimensional correlates of Long COVID symptom burden.

METHODS

This study focused on participants who reported having had COVID in Spring 2023 (n = 656; 85% female, mean age = 55, 59% college). Participants were categorized into symptom-burden groups using Latent Profile Analysis of 19 Long-COVID symptoms. Measures included demographics; quality of life and well-being (QOL); and COVID-specific stressors. Bivariate and multivariate associations of symptom burden were examined.

RESULTS

A three-profile solution reflected low, medium, and high symptom burden, aligning with diagnosis confirmation and treatment by a healthcare provider. Higher symptom burden was associated with reporting more comorbidities; being unmarried, difficulty paying bills, being disabled from work, not having a college degree, younger age, higher body mass index, having had COVID multiple times, worse reported QOL, greater reported financial hardship and worry; maladaptive coping, and worse healthcare disruption, health/healthcare stress, racial-inequity stress, family-relationship problems, and social support. Multivariate modeling revealed that financial hardship, worry, risk-taking, comorbidities, health/healthcare stress, and younger age were risk factors for higher symptom burden, whereas social support and reducing substance use were protective factors.

CONCLUSIONS

Long-COVID symptom burden is associated with substantial, modifiable social and behavioral factors. Most notably, financial hardship was associated with more than three times the risk of high versus low Long-COVID symptom burden. These findings suggest the need for multi-pronged support in the absence of a cure, such as symptom palliation, telehealth, social services, and psychosocial support.

Definitions and symptoms of the post-COVID syndrome: an updated systematic umbrella review

Post-COVID syndrome (PCS) describes a persistent complex of symptoms following a COVID-19 episode, lasting at least 4 to 12 weeks, depending on the specific criteria used for its definition. It is often associated with moderate to severe impairments of daily life and represents a major burden for many people worldwide. However, especially during the first two years of the COVID-19 pandemic, therapeutic and diagnostic uncertainties were prominent due to the novelty of the disease and non-specific definitions that overlooked functional deficits and lacked objective assessment. The present work comprehensively examines the status of PCS definitions as depicted in recent reviews and meta-analyses, alongside exploring associated symptoms and functional impairments. We searched the database Pubmed for reviews and meta-analysis evaluating PCS in the period between May 31, 2022, to December 31, 2023. Out of 95 studies, 33 were selected for inclusion in our analyses. Furthermore, we extended upon prior research by systematically recording the symptoms linked with PCS as identified in the studies. We found that fatigue, neurological complaints, and exercise intolerance were the most frequently reported symptoms. In conclusion, over the past eighteen months, there has been a notable increase in quantity and quality of research studies on PCS. However, there still remains a clear need for improvement, particularly with regard to the definition of the symptoms necessary for diagnosing this syndrome. Enhancing this aspect will render future research more comparable and precise, thereby advancing and understanding PCS.

Prognostic value of interleukin-6 serum levels in hospitalized COVID-19 patients: A case-control study in Iran

Introduction

The coronavirus pandemic (COVID-19) is an infectious disease with a high mortality rate that is challenging to treat. Cytokine storm is a crucial factor leading to acute respiratory distress syndrome in COVID-19 patients. Identifying factors that predict the severity of the disease may be primarily prognostic to guide drug therapy. The objective of this study was to investigate the prognostic role of interleukin 6 (IL-6) in the hospitalized patients infected with COVID-19.

Methods

This case-control study was conducted from October 2019 to April 2020 at Shahid Faqihi hospital in Iran. Fifty hospitalized COVID-19 patients and 50 healthy individuals were included while controlling demographics and comorbidities. IL-6 serum levels were measured and compared based on demographic characteristics (age, sex) and comorbidities in the case and control groups. Spearman rank correlation coefficient was also used to analyze the correlations between IL-6 levels and lung involvement in COVID-19 patients. Moreover, some laboratory parameters were compared based on the percentage of lung involvement.

Results

The level of IL-6 in the case group was significantly higher than the control (p ˂ 0.001). We observed a positive and significant correlation between the level of IL-6 and the severity of lung involvement (r = 0.0.79, p < 0.01). The median level of IL-6 in patients who showed more than 75% lung involvement was 573 (IQR = 320-850).

Conclusion

Available evidence suggests that high levels of IL-6 are associated with the severity of COVID-19. According to the results, it could be proposed that inhibition of IL-6 might be a target for therapeutic managements to reduce mortality in the patients with COVID-19.

A systematic review of quantitative EEG findings in Fibromyalgia, Chronic Fatigue Syndrome and Long COVID

Fibromyalgia Syndrome (FMS), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID (LC) are similar multisymptom clinical syndromes but with difference in dominant symptoms in each individual. There is existing and emerging literature on possible functional alterations of the central nervous system in these conditions. This review aims to synthesise and appraise the literature on resting-state quantitative EEG (qEEG) in FMS, ME/CFS and LC, drawing on previous research on FMS and ME/CFS to help understand neuropathophysiology of the new condition LC. A systematic search of MEDLINE, Embase, CINHAL, PsycINFO and Web of Science databases for articles published between December 1994 and September 2023 was performed. Out of the initial 2510 studies identified, 17 articles were retrieved that met all the predetermined selection criteria, particularly of assessing qEEG changes in one of the three conditions compared to healthy controls. All studies scored moderate to high quality on the Newcastle-Ottawa scale. There was a general trend for decreased low-frequency EEG band activity (delta, theta, and alpha) and increased high-frequency EEG beta activity in FMS, differing to that found in ME/CFS. The limited LC studies included in this review focused mainly on cognitive impairments and showed mixed findings not consistent with patterns observed in FMS and ME/CFS. Our findings suggest different patterns of qEEG brainwave activity in FMS and ME/CFS. Further research is required to explore whether there are phenotypes within LC that have EEG signatures similar to FMS or ME/CFS. This could inform identification of reliable diagnostic markers and possible targets for neuromodulation therapies tailored to each clinical syndrome.

Post-COVID conditions response: a collaborative approach to -establishing multidisciplinary clinics in Ecuador

INTRODUCTION

Worldwide, 3.7% (144.7 million) of people diagnosed with COVID-19 developed Post-COVID Conditions (PCC). Therefore, creating and implementing multidisciplinary rehabilitation clinics is important to address the needs of patients and improve overall recovery. This study was made possible with support from the United States Agency for International Development funded RISE program, under the terms of the cooperative agreement 7200AA19CA00003.

METHODS

This case study was conducted in Ecuador and describes the creation and implementation of 21 PCC rehabilitation clinics in primary healthcare centers and secondary level hospitals in 7 provinces across the country. Data was gathered for the identification of partnering health facilities and needs, for the evaluation of knowledge enhancement in health professionals after a specific training program, and for the measurement of key performance indicators. This article emphasizes the organization, educational strategies, and implementation of rehabilitation programs tailored specifically for the management of Post-COVID Conditions in Ecuador.

RESULTS

The implementation of PCC rehabilitation clinics involved a collaborative effort between the Ministry of Public Health (MOPH), the private sector and a non-governmental organization (Jhpiego). Twenty-one health facilities from the primary and secondary level of care were selected, and PCC rehabilitation implemented in 7 provinces of Ecuador. Additionally, 133 health providers were trained and a total of 13,846 patients treated, among whom 859 had a diagnosis of PCC. Medical doctors outperformed nurses in both pre- and post-tests scores. However, all healthcare professionals demonstrated comparable improvement in knowledge acquisition. Rehabilitation manuals were developed and adopted by the MOPH, rehabilitation equipment was donated and a mobile application, "RESPIRA", was developed and disseminated free of charge.

CONCLUSION

The establishment of PCC rehabilitation clinics in Ecuador was successful in identifying patients in need of early rehabilitation. The insights of this study can serve as a guide for the development of similar initiatives in other countries. Tailored courses are essential to address disparities and ensure comprehensive skill development and promote equitable healthcare delivery.

New insights into the pathogenesis of SARS-CoV-2 during and after the COVID-19 pandemic

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the respiratory distress condition known as COVID-19. This disease broadly affects several physiological systems, including the gastrointestinal, renal, and central nervous (CNS) systems, significantly influencing the patient's overall quality of life. Additionally, numerous risk factors have been suggested, including gender, body weight, age, metabolic status, renal health, preexisting cardiomyopathies, and inflammatory conditions. Despite advances in understanding the genome and pathophysiological ramifications of COVID-19, its precise origins remain elusive. SARS-CoV-2 interacts with a receptor-binding domain within angiotensin-converting enzyme 2 (ACE2). This receptor is expressed in various organs of different species, including humans, with different abundance. Although COVID-19 has multiorgan manifestations, the main pathologies occur in the lung, including pulmonary fibrosis, respiratory failure, pulmonary embolism, and secondary bacterial pneumonia. In the post-COVID-19 period, different sequelae may occur, which may have various causes, including the direct action of the virus, alteration of the immune response, and metabolic alterations during infection, among others. Recognizing the serious adverse health effects associated with COVID-19, it becomes imperative to comprehensively elucidate and discuss the existing evidence surrounding this viral infection, including those related to the pathophysiological effects of the disease and the subsequent consequences. This review aims to contribute to a comprehensive understanding of the impact of COVID-19 and its long-term effects on human health.

Lung Ultrasonography in the Evaluation of Late Sequelae of COVID-19 Pneumonia-A Comparison with Chest Computed Tomography: A Prospective Study

The onset of the COVID-19 pandemic allowed physicians to gain experience in lung ultrasound (LUS) during the acute phase of the disease. However, limited data are available on LUS findings during the recovery phase. The aim of this study was to evaluate the utility of LUS to assess lung involvement in patients with post-COVID-19 syndrome. This study prospectively enrolled 72 patients who underwent paired LUS and chest CT scans (112 pairs including follow-up). The most frequent CT findings were ground glass opacities (83.3%), subpleural lines (72.2%), traction bronchiectasis (37.5%), and consolidations (31.9%). LUS revealed irregular pleural lines as a common abnormality initially (56.9%), along with subpleural consolidation >2.5 mm ≤10 mm (26.5%) and B-lines (26.5%). A strong correlation was found between LUS score, calculated by artificial intelligence percentage involvement in ground glass opacities described in CT (r = 0.702, p < 0.05). LUS score was significantly higher in the group with fibrotic changes compared to the non-fibrotic group with a mean value of 19.4 ± 5.7 to 11 ± 6.6, respectively (p < 0.0001). LUS might be considered valuable for examining patients with persistent symptoms after recovering from COVID-19 pneumonia. Abnormalities identified through LUS align with CT scan findings; thus, LUS might potentially reduce the need for frequent chest CT examinations.

Understanding the olfactory role in post-COVID cognitive and neuropsychiatric manifestations

Introduction

Olfactory dysfunction (OD) is frequent after SARS-CoV-2 infection. The aim of this study was to examine if long-term OD is common in post-COVID condition, and the relationship between olfaction, cognition, neuropsychiatric symptoms, and disease duration in these patients.

Methods

This study included 121 participants with post-COVID condition and 51 healthy controls (HC). A comprehensive neuropsychological and neuropsychiatric assessment was conducted, encompassing various domains, including general cognition, processing speed, verbal fluency, attention, verbal memory, visual memory, visuoconstructive ability, visuospatial ability, abstraction, executive functions, anxious-depressive symptoms, general health perception, fatigue level, sleep quality, and olfaction. Statistical analyses were carried out to understand the relationship of OD with cognition, and its role as moderator variable.

Results

In total, 25% of the post-covid patients had a reduced smell capacity, while only 9.3% of HC presented OD. Post-COVID patients had statistically significantly worse cognitive performance and clinical status than HC. Verbal fluency (AUC = 0.85, p < 0.001), and attention (AUC = 0.82, p < 0.001) were the variables that best discriminate between groups. OD seemed to be a moderator between fatigue and cognition, and between disease duration and attention (β = -0.04; p = 0.014).

Discussion

The study highlights marked cognitive and neuropsychiatric sequelae in individuals post-COVID relative to HC. Olfactory impairment exhibits correlations with both cognitive performance and general health. Olfaction emerges as a potential prognostic marker owing to its moderating influence on disease severity indicators.

Pulmonary redox imbalance drives early fibroproliferative response in moderate/severe coronavirus disease-19 acute respiratory distress syndrome and impacts long-term lung abnormalities

BACKGROUND

COVID-19-associated pulmonary fibrosis remains frequent. This study aimed to investigate pulmonary redox balance in COVID-19 ARDS patients and possible relationship with pulmonary fibrosis and long-term lung abnormalities.

METHODS

Baseline data, chest CT fibrosis scores, N-terminal peptide of alveolar collagen III (NT-PCP-III), transforming growth factor (TGF)-β1, superoxide dismutase (SOD), reduced glutathione (GSH), oxidized glutathione (GSSG) and malondialdehyde (MDA) in bronchoalveolar lavage fluid (BALF) were first collected and compared between SARS-CoV-2 RNA positive patients with moderate to severe ARDS (n = 65, COVID-19 ARDS) and SARS-CoV-2 RNA negative non-ARDS patients requiring mechanical ventilation (n = 63, non-ARDS). Then, correlations between fibroproliferative (NT-PCP-III and TGF-β1) and redox markers were analyzed within COVID-19 ARDS group, and comparisons between survivor and non-survivor subgroups were performed. Finally, follow-up of COVID-19 ARDS survivors was performed to analyze the relationship between pulmonary abnormalities, fibroproliferative and redox markers 3 months after discharge.

RESULTS

Compared with non-ARDS group, COVID-19 ARDS group had significantly elevated chest CT fibrosis scores (p < 0.001) and NT-PCP-III (p < 0.001), TGF-β1 (p < 0.001), GSSG (p < 0.001), and MDA (p < 0.001) concentrations on admission, while decreased SOD (p < 0.001) and GSH (p < 0.001) levels were observed in BALF. Both NT-PCP-III and TGF-β1 in BALF from COVID-19 ARDS group were directly correlated with GSSG (p < 0.001) and MDA (p < 0.001) and were inversely correlated with SOD (p < 0.001) and GSH (p < 0.001). Within COVID-19 ARDS group, non-survivors (n = 28) showed significant pulmonary fibroproliferation (p < 0.001) with more severe redox imbalance (p < 0.001) than survivors (n = 37). Furthermore, according to data from COVID-19 ARDS survivor follow-up (n = 37), radiographic residual pulmonary fibrosis and lung function impairment improved 3 months after discharge compared with discharge (p < 0.001) and were associated with early pulmonary fibroproliferation and redox imbalance (p < 0.01).

CONCLUSIONS

Pulmonary redox imbalance occurring early in COVID-19 ARDS patients drives fibroproliferative response and increases the risk of death. Long-term lung abnormalities post-COVID-19 are associated with early pulmonary fibroproliferation and redox imbalance.

Integrating socio-economic vulnerability factors improves neighborhood-scale wastewater-based epidemiology for public health applications

Wastewater Based Epidemiology (WBE) of COVID-19 is a low-cost, non-invasive, and inclusive early warning tool for disease spread. Previously studied WBE focused on sampling at wastewater treatment plant scale, limiting the level at which demographic and geographic variations in disease dynamics can be incorporated into the analysis of certain neighborhoods. This study demonstrates the integration of demographic mapping to improve the WBE of COVID-19 and associated post-COVID disease prediction (here kidney disease) at the neighborhood level using machine learning. WBE was conducted at six neighborhoods in Seattle during October 2020 - February 2022. Wastewater processing and RT-qPCR were performed to obtain SARS-CoV-2 RNA concentration. Census data, clinical data of COVID-19, as well as patient data of acute kidney injury (AKI) cases reported during the study period were collected and the distribution across the city was studied using Geographic Information System (GIS) mapping. Further, we analyzed the data set to better understand socioeconomic impacts on disease prevalence of COVID-19 and AKI per neighborhood. The heterogeneity of eleven demographic factors (such as education and age among others) was observed within neighborhoods across the city of Seattle. Dynamics of COVID-19 clinical cases and wastewater SARS-CoV-2 varied across neighborhood with different levels of demographics. Machine learning models trained with data from the earlier stages of the pandemic were able to predict both COVID-19 and AKI incidence in the later stages of the pandemic (Spearman correlation coefficient of 0·546 - 0·904), with the most predictive model trained on the combination of wastewater data and demographics. The integration of demographics strengthened machine learning models' capabilities to predict prevalence of COVID-19, and of AKI as a marker for post-COVID sequelae. Demographic-based WBE presents an effective tool to monitor and manage public health beyond COVID-19 at the neighborhood level.

Practical Recommendations for Exercise Training in Patients with Long COVID with or without Post-exertional Malaise: A Best Practice Proposal

People with long COVID may suffer from a wide range of ongoing symptoms including fatigue, exertional dyspnea, reduced exercise performance, and others. In particular, impaired exercise performance is a condition that can be recovered in many people through an individualized physical exercise training program. However, clinical experience has shown that the presence of post-exertional malaise (PEM) is a significant barrier to physical exercise training in people with long COVID. Currently, there is no guideline or consensus available on how to apply exercise training in this cohort. Therefore, we conducted a literature review in the PubMed library using the following search terms: "COVID", "post-COVID", "long COVID" and "exercise" searching for studies from January 2020 to January 2024. Data from 46 trials were included. Exercise training regimes were very heterogeneous and none of these studies reported on the management of PEM in the context of an exercise training program. Based on the feedback from an additional survey that was answered by 14 international experts in the field of exercise training in long COVID, combined with the authors´ own extensive practical experience, a best practice proposal for exercise training recommendations has been developed. This proposal differentiates exercise procedures according to the presence of no, mild/moderate or severe PEM in people with long COVID. These recommendations may guide allied healthcare professionals worldwide in initiating and adjusting exercise training programs for people with long COVID, stratified according to the presence and severity of PEM.

Advances in the application of traditional Chinese medicine during the COVID-19 recovery period: A review

Since the emergence of the Coronavirus Disease 2019 (COVID-19) outbreak, significant advancements has been made in research, from limited knowledge about the disease to the development of a vaccine. Although the severity of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) appears to be decreasing and the threat of COVID-19 is waning, there have been widespread concerns about persistent symptoms or sequelae experienced by some patients even after recovering from COVID-19. Traditional Chinese medicine (TCM) has shown favorable treatment outcomes during the onset of COVID-19, and extensive studies have been carried out to explore the efficacy of TCM interventions during the COVID-19 recovery period. The purpose of this review is to comprehensively analyze these studies and provide new insights for the prevention and treatment of the post-COVID-19 condition.

Comparison of lifestyle, cognitive function, mental health, and quality of life between hospitalized older adults with COVID-19 and non-COVID-19 in South Korea: a cross-sectional study

BACKGROUND

The coronavirus disease (COVID-19) pandemic has greatly impacted older adults, resulting in many deaths. The impact of lifestyle and mental health on vulnerable groups, such as older adults, can be large and long lasting. Therefore, this study aimed to investigate the effects of COVID-19 confirmation on cognition, lifestyle, mental health, and quality of life in adults aged 55 years.

METHODS

The sample consisted of 111 people in the COVID group and 189 people in the non-COVID group aged over 55 years in South Korea. An online survey was conducted between January and May 2022. Participants responded to the following assessment tools: Yonsei Lifestyle Profile, Prospective and Retrospective Memory (PRMQ), Subjective Memory Complaints Questionnaire (SMCQ), Visual Analogue Scale, Patient Health Questionnaire-9 (PHQ-9), Insomnia Severity Index (ISI), Fear of COVID-19 Scale (FCV-19 S), and the World Health Organization Quality of Life Scale abbreviated version (WHOQOL-BREF). Differences in lifestyle, cognition, depression, anxiety, and quality of life were compared between the two groups.

RESULTS

There were significant differences in physical activity, diet, the total score of the PRMQ, PM (a sub-score of the PRMQ), PHQ-9, Korean version of the ISI (ISI-K), and WHOQOL-BREF scores between the COVID and non-COVID groups. However, there were no significant differences in activity participation, Self-Rating Anxiety Scale (SAS), or FCV-19 S between groups.

CONCLUSIONS

The study confirms that COVID-19 negatively affects memory, physical activity, diet, quality of life, depression, and insomnia in the older adults. Therefore, this study implicated that prevention and intervention strategies required improving the memory, lifestyle, and mental health of older adults with COVID-19.

TRIAL REGISTRATION

The study was conducted in accordance with the Declaration of Helsinki, and approved by the Institutional Review Board of Yonsei university in Korea (Registration number: 1041849-202112-SB-226-03, Date of registration: 01042022).

Type I interferon pathway genetic variants in severe COVID-19

Coronavirus Disease 2019 (COVID-19) is an infectious disease caused by SARS-CoV-2. According to the World Health Organization (WHO), there have been over 760 million reported cases and over 6 million deaths caused by this disease worldwide. The severity of COVID-19 is based on symptoms presented by the patient and is divided as asymptomatic, mild, moderate, severe, and critical. The manifestations are interconnected with genetic variations. The innate immunity is the quickest response mechanism of an organism against viruses. Type I interferon pathway plays a key role in antiviral responses due to viral replication inhibition in infected cells and adaptive immunity stimulation induced by interferon molecules. Thus, variants in type I interferon pathway's genes are being studied in different COVID-19 manifestations. This review summarizes the role of variants in type I interferon pathway's genes on prognosis and severity progression of COVID-19.

Alterations in microbiota of patients with COVID-19: implications for therapeutic interventions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently caused a global pandemic, resulting in more than 702 million people being infected and over 6.9 million deaths. Patients with coronavirus disease (COVID-19) may suffer from diarrhea, sleep disorders, depression, and even cognitive impairment, which is associated with long COVID during recovery. However, there remains no consensus on effective treatment methods. Studies have found that patients with COVID-19 have alterations in microbiota and their metabolites, particularly in the gut, which may be involved in the regulation of immune responses. Consumption of probiotics may alleviate the discomfort caused by inflammation and oxidative stress. However, the pathophysiological process underlying the alleviation of COVID-19-related symptoms and complications by targeting the microbiota remains unclear. In the current study, we summarize the latest research and evidence on the COVID-19 pandemic, together with symptoms of SARS-CoV-2 and vaccine use, with a focus on the relationship between microbiota alterations and COVID-19-related symptoms and vaccine use. This work provides evidence that probiotic-based interventions may improve COVID-19 symptoms by regulating gut microbiota and systemic immunity. Probiotics may also be used as adjuvants to improve vaccine efficacy.

SARS-CoV-2 Spike Protein S1 Domain Accelerates α-Synuclein Phosphorylation and Aggregation in Cellular Models of Synucleinopathy

The 2019 novel coronavirus disease (COVID-19) is an infectious disease that began to spread globally since 2019. Some COVID-19 patients have neurological complications, such as olfactory disorders and movement disorders, which coincide with the symptoms of Parkinson's disease (PD). Increasing imaging and autopsy evidence supports that the density of dopaminergic neurons in the nigrostriatal pathway is damaged in some COVID-19 patients. However, the underlying mechanism that causes PD-like symptoms remains unclear. PD is an age-related neurodegenerative disease with Lewy bodies (LBs) as its histopathologic feature. The main component of LBs is abnormally aggregated α-synuclein (α-syn). The prion-like propagation of α-syn aggregates plays a key role in the onset and progression of PD. The spike protein (S protein) of SARS-CoV-2 is a heparin-binding protein that mediates the entry of the virus into host cells. Here we found that the S1 domain interacts with α-syn and promotes α-syn aggregation. The S1 domain induces mitochondrial dysfunction, oxidative stress, and cytotoxicity. The S1-seeded α-syn fibrils show enhanced seeding activity and induce synaptic damage and cytotoxicity. Thus, the S1 domain of SARS-CoV-2 promotes the aggregation of α-syn in the cellular model of synucleinopathy and may contribute to the pathogenesis of PD.

Precision nutrition to reset virus-induced human metabolic reprogramming and dysregulation (HMRD) in long-COVID

SARS-CoV-2, the etiological agent of COVID-19, is devoid of any metabolic capacity; therefore, it is critical for the viral pathogen to hijack host cellular metabolic machinery for its replication and propagation. This single-stranded RNA virus with a 29.9 kb genome encodes 14 open reading frames (ORFs) and initiates a plethora of virus-host protein-protein interactions in the human body. These extensive viral protein interactions with host-specific cellular targets could trigger severe human metabolic reprogramming/dysregulation (HMRD), a rewiring of sugar-, amino acid-, lipid-, and nucleotide-metabolism(s), as well as altered or impaired bioenergetics, immune dysfunction, and redox imbalance in the body. In the infectious process, the viral pathogen hijacks two major human receptors, angiotensin-converting enzyme (ACE)-2 and/or neuropilin (NRP)-1, for initial adhesion to cell surface; then utilizes two major host proteases, TMPRSS2 and/or furin, to gain cellular entry; and finally employs an endosomal enzyme, cathepsin L (CTSL) for fusogenic release of its viral genome. The virus-induced HMRD results in 5 possible infectious outcomes: asymptomatic, mild, moderate, severe to fatal episodes; while the symptomatic acute COVID-19 condition could manifest into 3 clinical phases: (i) hypoxia and hypoxemia (Warburg effect), (ii) hyperferritinemia ('cytokine storm'), and (iii) thrombocytosis (coagulopathy). The mean incubation period for COVID-19 onset was estimated to be 5.1 days, and most cases develop symptoms after 14 days. The mean viral clearance times were 24, 30, and 39 days for acute, severe, and ICU-admitted COVID-19 patients, respectively. However, about 25-70% of virus-free COVID-19 survivors continue to sustain virus-induced HMRD and exhibit a wide range of symptoms that are persistent, exacerbated, or new 'onset' clinical incidents, collectively termed as post-acute sequelae of COVID-19 (PASC) or long COVID. PASC patients experience several debilitating clinical condition(s) with >200 different and overlapping symptoms that may last for weeks to months. Chronic PASC is a cumulative outcome of at least 10 different HMRD-related pathophysiological mechanisms involving both virus-derived virulence factors and a multitude of innate host responses. Based on HMRD and virus-free clinical impairments of different human organs/systems, PASC patients can be categorized into 4 different clusters or sub-phenotypes: sub-phenotype-1 (33.8%) with cardiac and renal manifestations; sub-phenotype-2 (32.8%) with respiratory, sleep and anxiety disorders; sub-phenotype-3 (23.4%) with skeleto-muscular and nervous disorders; and sub-phenotype-4 (10.1%) with digestive and pulmonary dysfunctions. This narrative review elucidates the effects of viral hijack on host cellular machinery during SARS-CoV-2 infection, ensuing detrimental effect(s) of virus-induced HMRD on human metabolism, consequential symptomatic clinical implications, and damage to multiple organ systems; as well as chronic pathophysiological sequelae in virus-free PASC patients. We have also provided a few evidence-based, human randomized controlled trial (RCT)-tested, precision nutrients to reset HMRD for health recovery of PASC patients.

COVID-19-associated costs and mortality in Germany: an incidence-based analysis from a payer's perspective

BACKGROUND

This study aims to estimate average COVID-19-associated healthcare costs per capita in Germany from a payer perspective. In addition, insights into COVID-19-associated mortality should be gained.

METHODS

For this purpose, a retrospective longitudinal analysis using health insurance claims data was performed. Patients affected by COVID-19 in Q1/2021 (investigation group (IG)) were compared to a matched non-COVID-19 control group (CG) (1:1 propensity score matching (PSM)). Mean values of healthcare costs in 2020 and 2021 were computed for both groups and then separated by age and by development of Post-COVID-19 Syndrome (PCS). Group differences were examined using Mann-Whitney U test (α = 0.05). Difference-in-Differences approach (DiD) was used to estimate average cost effects of COVID-19 in 2021. Concerning mortality, the number of deaths in 2021 was compared between IG and CG using χ2 test of independence.

RESULTS

A total of 8,014 insurants were included (n = 4,007 per group; n = 536 per group examining PCS patients only). Total healthcare costs varied a lot in the sample, were comparable between IG and CG in 2020, but were significantly higher in the IG in 2021 (DiD estimate = € 1,063 (in total); € 3,242 (PCS group)). This was more pronounced in the older age groups. High hospital costs of a minority of patients were the most influential driver of COVID-19-associated healthcare costs. Mortality was more than doubled in the IG (tripled in patients aged ≥ 60).

CONCLUSIONS

COVID-19 is associated with significantly increased healthcare costs and mortality, especially in older age groups. The additional development of PCS further increases the costs of COVID-19.

Symptom intensity of post-COVID and long COVID syndromes in patients entering rehabilitation treatment

Introduction

The problem of post-COVID symptoms is still being analysed. Many of them may be related to other conditions, but the new appearance and greater intensity of some of them, e.g. fatigue, musculoskeletal pain, and neuropathic pain, seem to be related to a previous viral infection. Efforts are being made to determine in more detail the most characteristic symptoms of post-COVID syndrome. The conditions of rehabilitation after COVID-19 provide an opportunity for such observations. In rehabilitation centres and sanatoriums, it is possible to compare patients with post-COVID syndrome and other patients referred for rehabilitation, who constitute a natural control group. Such a comparison is the aim of the present work.

Material and methods

The study included 59 post-COVID-19 patients and 57 sanatorium patients without COVID (non-COVID group) as a control group. The 31-element questionnaire ("Post-COVID syndrome symptoms assessment card") was part of the routine management of post-COVID patients referred for rehabilitation after symptomatic SARS-CoV-2 infection in Polish conditions. In the control group, the questionnaire was introduced as a part of a physical examination and an interview regarding the symptoms reported by the patient before standard rehabilitation. The questions were scored in the scale from 0 to a maximum of 10 points. Each patient gave informed consent to the use of the questionnaire for research purposes.

Results

Symptoms of the highest intensity in the COVID-19 group were: feeling unwell after physical effort (avg. 6.25 points), chronic fatigue (avg. 5.97 points), dyspnoea on exertion (avg. 5.83 points), concentration disturbances (avg. 4.93), muscle pain (avg. 4.92), joint pain (avg. 4.86), memory disorders (avg. 4.81 points), sleep disorders (avg. 4.05 points), numbness of the limbs (avg. 3.73 points), tingling in the limbs (avg. 3.68 points).Symptoms of highest intensity in patients in the non-COVID-19 group: joint pain (avg. 4.61 points), tingling in the limbs (avg. 2.84 points), numbness of the limbs (avg. 2.79 points), muscle pain (avg. 2.11 points).There was no statistically significant difference between the group under examination and the control group in the following symptoms: fever, diarrhoea, abdominal pain, resting dyspnoea, olfactory disorders, joint pain, tingling in the limbs and numbness of the limbs.

Conclusions

The results of this study show symptoms of the highest intensity with post-COVID syndromes. However, also symptoms that are a problem both in post-COVID and non-COVID patients, i.e. joint pain, tingling in and numbness of the limbs were identified. This confirms that the control non-COVID group consisted of patients referred for rehabilitation treatment mainly due to musculoskeletal problems and chronic pain.

rTMS for post-covid-19 condition: A sham-controlled case series involving iTBS-300 and iTBS-600

Post-Covid-19 Condition (PCC) is a syndrome comprised of symptoms persisting 3 months or more beyond SARS-CoV-2 primary infection. It is typically characterized by fatigue, cognitive problems and psychiatric symptoms, as well as cardiac symptoms that contribute to exercise intolerance in many. Despite the high prevalence of PCC among those with a prior SARS-CoV-2 infection, there is currently no widely accepted rehabilitation strategy, and many conventional modalities are movement-based. Non-invasive brain stimulation methods such as repetitive transcranial magnetic stimulation (rTMS) may have some potential to alleviate the cognitive and affective symptoms of PCC without reliance on exercise. The purpose of the present study was to explore the feasibility and tolerability of using rTMS to treat symptoms of "brain fog" and affective disturbance among those living with PCC, using a case series design. We enrolled four individuals with PCC following a confirmed SARS-CoV-2 infection, at least 3 months after the resolution of the primary infection. Participants were randomized to 4 sessions of active and 2 sessions of sham intermittent theta-burst stimulation (iTBS); two intensities of iTBS were evaluated: iTBS-300 and iTBS-600. No adverse events occurred in active or sham stimulation; 2 participants reported tingling sensation on the scalp but no other tolerability issues. Trends in symptoms suggested improvements in cognitive interference, quality of life, and anxiety in the majority of participants. In summary, in this case series iTBS was well tolerated among 4 individuals with PCC; active stimulation was associated with positive trends in some primary symptom clusters as compared with sham stimulation. Future studies should examine the effects of iTBS on PCC symptoms in the context of experimental studies and randomized controlled trials.

Prevalence and risk factors for persistent symptoms after COVID-19: a systematic review and meta-analysis

BACKGROUND

Long-term physical and mental persistent symptoms after COVID-19 represent a growing global public health concern. However, there remains a substantial knowledge gap regarding their prevalence and risk factors.

OBJECTIVES

To estimate the prevalence and risk factors for persistent symptoms after COVID-19.

METHODS OF DATA SYNTHESIS

We used a random-effects model to pool persistent symptom prevalence and risk ratios comparing COVID-19 patients with non-COVID-19 individuals.

DATA SOURCES

Electronic databases were searched for studies published from December 2019 to January 2023.

STUDY ELIGIBILITY CRITERIA

Eligible studies that reported the prevalence and risk factors for persistent symptoms after COVID-19 were included.

PARTICIPANTS

Patients who recovered from COVID-19.

ASSESSMENT OF RISK OF BIAS

The Joanna Briggs Institute critical appraisal tool was used to assess the risk of bias in prevalence studies, whereas the risk of bias in cohort studies was evaluated with the Newcastle-Ottawa Scale.

RESULTS

After screening 4359 studies, a total of 211 eligible studies were included, covering a population of 13 368 074 individuals. Fatigue, dyspnoea, post-traumatic stress disorder, anxiety, and depression were the most frequently reported persistent symptoms after COVID-19. Subgroup analyses revealed that individuals with more severe illness in the acute phase or from Europe exhibited a higher prevalence of certain symptoms, whereas children demonstrated a lower prevalence. Furthermore, COVID-19 patients had a significantly higher prevalence of most persistent symptoms compared with non-COVID-19 individuals. Factors frequently associated with a higher prevalence of persistent symptoms included female gender, advanced age, severe illness during the acute phase of COVID-19, multiple comorbidities, an extended duration of hospital stay, and a high body mass index.

CONCLUSION

This meta-analysis provides a thorough review of the prevalence and risk factors for persistent symptoms following COVID-19. The findings underscore the importance of long-term monitoring and support for individuals recovering from COVID-19.

SARS-CoV-2 vaccination may mitigate dysregulation of IL-1/IL-18 and gastrointestinal symptoms of the post-COVID-19 condition

The rapid development of safe and effective vaccines helped to prevent severe disease courses after SARS-CoV-2 infection and to mitigate the progression of the COVID-19 pandemic. While there is evidence that vaccination may reduce the risk of developing post-COVID-19 conditions (PCC), this effect may depend on the viral variant. Therapeutic effects of post-infection vaccination have been discussed but the data for individuals with PCC remains inconclusive. In addition, extremely rare side effects after SARS-CoV-2 vaccination may resemble the heterogeneous PCC phenotype. Here, we analyze the plasma levels of 25 cytokines and SARS-CoV-2 directed antibodies in 540 individuals with or without PCC relative to one or two mRNA-based COVID-19 vaccinations as well as in 20 uninfected individuals one month after their initial mRNA-based COVID-19 vaccination. While none of the SARS-CoV-2 naïve individuals reported any persisting sequelae or exhibited PCC-like dysregulation of plasma cytokines, we detected lower levels of IL-1β and IL-18 in patients with ongoing PCC who received one or two vaccinations at a median of six months after infection as compared to unvaccinated PCC patients. This reduction correlated with less frequent reporting of persisting gastrointestinal symptoms. These data suggest that post-infection vaccination in patients with PCC might be beneficial in a subgroup of individuals displaying gastrointestinal symptoms.

Identification of key genes associated with persistent immune changes and secondary immune activation responses induced by influenza vaccination after COVID-19 recovery by machine learning methods

COVID-19 is hypothesized to exert enduring effects on the immune systems of patients, leading to alterations in immune-related gene expression. This study aimed to scrutinize the persistent implications of SARS-CoV-2 infection on gene expression and its influence on subsequent immune activation responses. We designed a machine learning-based approach to analyze transcriptomic data from both healthy individuals and patients who had recovered from COVID-19. Patients were categorized based on their influenza vaccination status and then compared with healthy controls. The initial sample set encompassed 86 blood samples from healthy controls and 72 blood samples from recuperated COVID-19 patients prior to influenza vaccination. The second sample set included 123 blood samples from healthy controls and 106 blood samples from recovered COVID-19 patients who had been vaccinated against influenza. For each sample, the dataset captured expression levels of 17,060 genes. Above two sample sets were first analyzed by seven feature ranking algorithms, yielding seven feature lists for each dataset. Then, each list was fed into the incremental feature selection method, incorporating three classic classification algorithms, to extract essential genes, classification rules and build efficient classifiers. The genes and rules were analyzed in this study. The main findings included that NEXN and ZNF354A were highly expressed in recovered COVID-19 patients, whereas MKI67 and GZMB were highly expressed in patients with secondary immune activation post-COVID-19 recovery. These pivotal genes could provide valuable insights for future health monitoring of COVID-19 patients and guide the creation of continued treatment regimens.

Microstructural brain abnormalities, fatigue, and cognitive dysfunction after mild COVID-19

Although some studies have shown neuroimaging and neuropsychological alterations in post-COVID-19 patients, fewer combined neuroimaging and neuropsychology evaluations of individuals who presented a mild acute infection. Here we investigated cognitive dysfunction and brain changes in a group of mildly infected individuals. We conducted a cross-sectional study of 97 consecutive subjects (median age of 41 years) without current or history of psychiatric symptoms (including anxiety and depression) after a mild infection, with a median of 79 days (and mean of 97 days) after diagnosis of COVID-19. We performed semi-structured interviews, neurological examinations, 3T-MRI scans, and neuropsychological assessments. For MRI analyses, we included a group of non-infected 77 controls. The MRI study included white matter (WM) investigation with diffusion tensor images (DTI) and functional connectivity with resting-state functional MRI (RS-fMRI). The patients reported memory loss (36%), fatigue (31%) and headache (29%). The quantitative analyses confirmed symptoms of fatigue (83% of participants), excessive somnolence (35%), impaired phonemic verbal fluency (21%), impaired verbal categorical fluency (13%) and impaired logical memory immediate recall (16%). The WM analyses with DTI revealed higher axial diffusivity values in post-infected patients compared to controls. Compared to controls, there were no significant differences in the functional connectivity of the posterior cingulum cortex. There were no significant correlations between neuropsychological scores and neuroimaging features (including DTI and RS-fMRI). Our results suggest persistent cognitive impairment and subtle white matter abnormalities in individuals mildly infected without anxiety or depression symptoms. The longitudinal analyses will clarify whether these alterations are temporary or permanent.

Persisting Gastrointestinal Symptoms in Children with SARS-CoV-2: Temporal Evolution over 18 Months and Possible Role of Lactoferrin

BACKGROUND AND AIM

Persisting gastrointestinal symptoms are reported to be relatively common in children with long COVID; however, their detailed characterization and long-term outcomes have not yet been described.

METHODS

We performed a retrospective study aiming to investigate the temporal evolution of gastrointestinal symptoms in children with SARS-CoV-2, from acute infection to 18-months follow-up. To further investigate possible therapeutic strategies, we evaluated the role of lactoferrin in improving gastrointestinal symptoms in these children, compared with those not treated.

RESULTS

A total of 1224 patients (47.7% females) were included. Of these participants, 246 (19.8%) were vaccinated and 143 (11.5%) presented with comorbidities. A total of 175 patients (14.1%) presented gastrointestinal symptoms during acute infection, 54 (4.4%) at three months, 23 (1.9%) at six months, 6 (3.3%) at twelve months, and 2 (2.3%) at eighteen months follow-up. At six months follow-up, children who were treated with 3 months oral lactoferrin had less persisting symptoms compared to those who did not receive lactoferrin, although this difference was not statistically significant (three patients (25%) in the lactoferrin group vs. fourteen patients (33.3%) not treated, p = 0.73), probably due to the low number of patients with persisting GI symptoms.

CONCLUSIONS

GI symptoms are relatively common during acute SARS-CoV-2 infection in children, and a non-negligible proportion of these children reported persisting symptoms for up to 12-18 months after the acute infection. In addition, we found a trend even if statistically nonsignificant toward faster improvement of persisting gastrointestinal symptoms in children with long COVID treated with lactoferrin. Despite the limitations relating to the present study's design, given the significant burden of gastrointestinal symptoms in children with long COVID, our findings provide the basis to perform a prospective, placebo-controlled study.

Single-cell RNA sequencing reveals characteristics of myeloid cells in post-acute sequelae of SARS-CoV-2 patients with persistent respiratory symptoms

Background

Although our understanding of the immunopathology and subsequent risk and severity of COVID-19 disease is evolving, a detailed account of immune responses that contribute to the long-term consequences of pulmonary complications in COVID-19 infection remains unclear. Few studies have detailed the immune and cytokine profiles associated with post-acute sequelae of SARS-CoV-2 infection (PASC) with persistent pulmonary symptoms. The dysregulation of the immune system that drives pulmonary sequelae in COVID-19 survivors and PASC sufferers remains largely unknown.

Results

To characterize the immunological features of pulmonary PASC (PPASC), we performed droplet-based single-cell RNA sequencing (scRNA-seq) to study the transcriptomic profiles of peripheral blood mononuclear cells (PBMCs) from a participant naïve to SARS-CoV-2 (Control) (n=1) and infected with SARS-CoV-2 with chronic pulmonary symptoms (PPASC) (n=2). After integrating scRNA-seq data with a naïve participant from a published dataset, 11 distinct cell populations were identified based on the expression of canonical markers. The proportion of myeloid-lineage cells ([MLCs]; CD14+/CD16+monocytes, and dendritic cells) was increased in PPASC (n=2) compared to controls (n=2). MLCs from PPASC displayed up-regulation of genes associated with pulmonary symptoms/fibrosis, while glycolysis metabolism-related genes were downregulated. Similarly, pathway analysis showed that fibrosis-related (VEGF, WNT, and SMAD) and cell death pathways were up-regulated, but immune pathways were down-regulated in PPASC. Further comparison of PPASC with scRNA-seq data with Severe COVID-19 (n=4) data demonstrated enrichment of fibrotic transcriptional signatures. In PPASC, we observed interactive VEGF ligand-receptor pairs among MLCs, and network modules in CD14+ (cluster 4) and CD16+ (Cluster 5) monocytes displayed a significant enrichment for biological pathways linked to adverse COVID-19 outcomes, fibrosis, and angiogenesis. Further analysis revealed a distinct metabolic alteration in MLCs with a down-regulation of glycolysis/gluconeogenesis in PPASC compared to SARS-CoV-2 naïve samples.

Conclusion

Analysis of a small scRNA-seq dataset demonstrated alterations in the immune response and cellular landscape in PPASC. The presence of elevated MLC levels and their corresponding gene signatures associated with fibrosis, immune response suppression, and altered metabolic states suggests a potential role in PPASC development.

The determinants of COVID-induced brain dysfunctions after SARS-CoV-2 infection in hospitalized patients

The severity of the pandemic and its consequences on health and social care systems were quite diverse and devastating. COVID-19 was associated with an increased risk of neurological and neuropsychiatric disorders after SARS-CoV-2 infection. We did a cross-sectional study of 3 months post-COVID consequences of 178 Cuban subjects. Our study has a unique CUBAN COVID-19 cohort of hospitalized COVID-19 patients and healthy subjects. We constructed a latent variable for pre-health conditions (PHC) through Item Response Theory (IRT) and for post-COVID neuropsychiatric symptoms (Post-COVID-NPS) through Factor Analysis (FA). There seems to be a potential causal relationship between determinants of CIBD and post-COVID-NPS in hospitalized COVID-19 patients. The causal relationships accessed by Structural Equation Modeling (SEM) revealed that PHC (p < 0.001) and pre-COVID cognitive impairments (p < 0.001) affect the severity of COVID-19 patients. The severity of COVID-19 eventually results in enhanced post-COVID-NPS (p < 0.001), even after adjusting for confounders (age, sex, and pre-COVID-NPS). The highest loadings in PHC were for cardiovascular diseases, immunological disorders, high blood pressure, and diabetes. On the other hand, sex (p < 0.001) and pre-COVID-NPS including neuroticism (p < 0.001), psychosis (p = 0.005), cognition (p = 0.036), and addiction (p < 0.001) were significantly associated with post-COVID-NPS. The most common neuropsychiatric symptom with the highest loadings includes pain, fatigue syndrome, autonomic dysfunctionalities, cardiovascular disorders, and neurological symptoms. Compared to healthy people, COVID-19 patients with pre-health comorbidities or pre-neuropsychiatric conditions will have a high risk of getting severe COVID-19 and long-term post-COVID neuropsychiatric consequences. Our study provides substantial evidence to highlight the need for a complete neuropsychiatric follow-up on COVID-19 patients (with severe illness) and survivors (asymptomatic patients who recovered).

Significant burden of post-COVID exertional dyspnoea in a South-Italy region: knowledge of risk factors might prevent further critical overload on the healthcare system

Background

Exertional dyspnoea in post-COVID syndrome is a debilitating manifestation, requiring appropriate comprehensive management. However, limited-resources healthcare systems might be unable to expand their healthcare-providing capacity and are expected to be overwhelmed by increasing healthcare demand. Furthermore, since post-COVID exertional dyspnoea is regarded to represent an umbrella term, encompassing several clinical conditions, stratification of patients with post-COVID exertional dyspnoea, depending on risk factors and underlying aetiologies might provide useful for healthcare optimization and potentially help relieve healthcare service from overload. Hence, we aimed to investigate the frequency, functional characterization, and predictors of post-COVID exertional dyspnoea in a large cohort of post-COVID patients in Apulia, Italy, at 3-month post-acute SARS-CoV-2 infection.

Methods

A cohort of laboratory-confirmed 318 patients, both domiciliary or hospitalized, was evaluated in a post-COVID Unit outpatient setting. Post-COVID exertional dyspnoea and other post-COVID syndrome manifestations were collected by medical history. Functional characterization of post-COVID exertional dyspnoea was performed through a 6-min walking test (6-mwt). The association of post-COVID exertional dyspnoea with possible risk factors was investigated through univariate and multivariate logistic regression analysis.

Results

At medical evaluation, post-COVID exertional dyspnoea was reported by as many as 190/318 patients (59.7%), showing relatively high prevalence also in domiciliary-course patients. However, functional characterization disclosed a 6-mwt-based desaturation walking drop in only 24.1% of instrumental post-COVID exertional dyspnoea patients. Multivariate analysis identified five independent predictors significantly contributing to PCED, namely post-COVID-fatigue, pre-existing respiratory co-morbidities, non-asthmatic allergy history, age, and acute-phase-dyspnoea. Sex-restricted multivariate analysis identified a differential risk pattern for males (pre-existing respiratory co-morbidities, age, acute-phase-dyspnoea) and females (post-COVID-fatigue and acute-phase-dyspnoea).

Conclusion

Our findings revealed that post-COVID exertional dyspnoea is characterized by relevant clinical burden, with potential further strain on healthcare systems, already weakened by pandemic waves. Sex-based subgroup analysis reveals sex-specific dyspnoea-underlying risk profiles and pathogenic mechanisms. Knowledge of sex-specific risk-determining factors might help optimize personalized care management and healthcare resources.

Exploring the perceptions and lived experiences of family members living with people diagnosed with COVID-19 in South Africa: a descriptive phenomenological study

BACKGROUND

The incidence and prevalence of COVID-19 continues to escalate globally, with the consequence to quality of life, the economies of nations and various sectors of society. While there is substantial research on the impact and experiences of the COVID-19 pandemic, little remains known about the perceptions and lived experiences of families living with people diagnosed with COVID-19, particularly within the South African context.

PURPOSE

To explore the perceptions and lived experiences of family members  living with people diagnosed with COVID-19 in South Africa.

METHODS

A descriptive phenomenological design was used. Data were collected from 15 participants who were family members of people diagnosed with COVID-19 in South Africa. Purposive snowball sampling was used to identify and recruit participants, and data were collected at community level in KwaZulu-Natal, Western Cape and Gauteng, South Africa. Individual in-depth interviews were used to collect the data, and an audio tape was used to record all interviews. Data were transcribed verbatim and analysed using a phenomenological data analysis processes. Ethical approval to conduct the study was obtained from the University of KwaZulu-Natal Research Ethics Committee-reference number: BREC00003228/2021.

RESULTS

Four super-ordinate themes emerged in relation to the perceptions and lived experiences of family members  living with people diagnosed with COVID-19 in South Africa. The superordinate themes were: (1) sources of information about COVID-19, (2) pandemic  perceptions and experiences, (3) impact of diagnosis and related burden and (4) aftermath of living with a family member diagnosed with COVID-19.

DISCUSSION AND CONCLUSION

Family members' perceptions and lived experiences of COVID-19 are largely influenced by media, moreover, the impact of diagnosis has consequences for the physical, mental and emotional well-being of family members. Diagnosis disrupts family dynamics by depleting financial resources due to  the caregiver burden experienced. The findings thus imply that provision of psychosocial support is imperative for families living with persons diagnosed with COVID-19.

Impact of Comorbidity on the Duration from Symptom Onset to Death in Patients with Coronavirus Disease 2019: A Retrospective Study of 104,753 Cases in Pakistan

(1) Background: The evidence indicates that comorbidities are associated with an increase in the risk of death from coronavirus disease 2019 (COVID-19). It is unclear whether such an association is different for various combinations of chronic disease comorbidities. (2) Methods: From 16 March 2020 to 30 November 2021, 104,753 patients with confirmed COVID-19 from Khyber Pakhtunkhwa Province, Pakistan, were studied to determine the association between comorbidities and the duration from symptom onset to death in patients with COVID-19 by stratifying their comorbidity status. (3) Results: The patients with comorbidities had an 84% (OR, 0.16; 95% CI, 0.14 to 0.17) decrease in the duration from symptom onset to death, as opposed to patients without a comorbidity. Among the patients with only one comorbidity, chronic lung disease (OR, 0.06; 95% CI, 0.03 to 0.09) had a greater impact on the duration from symptom onset to death than hypertension (OR, 0.15; 95% CI, 0.13 to 0.18) or diabetes (OR, 0.15; 95% CI, 0.12 to 0.18). The patients with both hypertension and diabetes had the shortest duration (OR, 0.17; 95% CI, 0.14 to 0.20) among the patients with two comorbidities. (4) Conclusions: Comorbidity yielded significant adverse impacts on the duration from symptom onset to death in COVID-19 patients in Pakistan. The impact varied with different combinations of chronic disease comorbidities in terms of the number and type of comorbidities.

How do the Social Determinants of Health Impact the Post-Acute Sequelae of COVID-19: A Critical Review

The review critically analyzes the social determinants of health (SDOH) variables in the current literature of patients with post-acute sequelae (PASC) of COVID-19 in the United States. Race, gender, and age were discussed as well as health outcomes, severity of illness, and phenotypes of long-COVID. Most research was retrospectively with samples that had access to health insurance, which did not capture populations with poor or no access to health care. More research is needed that directly addresses the impact on SDOH on PASC. The current literature is sparse and provides little actionable information.

Resolution of Eosinophilic Pneumonia after Coronavirus Disease 2019 without Systemic Corticosteroids

Pulmonary and extrapulmonary complications after coronavirus disease 2019 (COVID-19) have been major public health concerns during the COVID-19 pandemic. Although post-COVID-19 pulmonary manifestations cover a wide spectrum, eosinophilic pneumonia (EP) has rarely been reported. To date, only four cases of EP potentially triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, all of which required systemic corticosteroid therapy. We herein report the first case of post-COVID-19 EP resolution without systemic corticosteroid therapy. We also review the literature regarding EP associated with SARS-CoV-2 infection and vaccination.

Aftereffects in Epigenetic Age Related to Cognitive Decline and Inflammatory Markers in Healthcare Personnel with Post-COVID-19: A Cross-Sectional Study

Purpose

Epigenetic age and inflammatory markers have been proposed as indicators of severity and mortality in patients with COVID-19. Furthermore, they have been associated with the occurrence of neurological symptoms, psychiatric manifestations, and cognitive impairment. Therefore, we aimed to explore the possible associations between epigenetic age, neuropsychiatric manifestations and inflammatory markers (neutrophil-lymphocyte ratio [NLR], platelet-lymphocyte ratio [PLR], monocyte-lymphocyte ratio [MLR], and systemic immune-inflammation index [SII]) in healthcare personnel with post-COVID condition.

Patients and Methods

We applied the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) tests to 51 Mexican healthcare workers with post-COVID-19 condition; we also estimated their epigenetic age using the PhenoAge calculator.

Results

The participants had a post-COVID condition that lasted a median of 14 months (range: 1-20). High NLR (>1.73) had association with mild cognitive impairment by MMSE (p=0.013). Likewise, high MLR (>0.24) were associated with language domain in MOCA (p=0.046). Low PLR (<103.9) was also related to delayed recall in MOCA (p=0.040). Regarding comorbidities, hypertension was associated with SII (p=0.007), overweight with PLR (p=0.047) and alcoholism was associated with MLR (p=0.043). Interestingly, we observed associations of low PLR (<103.9) and low SII (<1.35) levels with increased duration of post-COVID condition (p=0.027, p=0.031). Likewise, increases in PhenoAge were associated with high levels of SII (OR=1.11, p=0.049), PLR (OR=1.12, p=0.035) and MLR (OR=1.12, p=0.030).

Conclusion

We observed neurocognitive changes related to inflammatory markers and increases in epigenetic age in healthcare personnel with post-COVID-19 condition. Future research is required to assess mental and physical health in individuals with post-COVID-19 symptoms.

An Overview of Long COVID Support Services in Australia and International Clinical Guidelines, With a Proposed Care Model in a Global Context

Objective: To identify gaps among Australian Long COVID support services and guidelines alongside recommendations for future health programs. Methods: Electronic databases and seven government health websites were searched for Long COVID-specific programs or clinics available in Australia as well as international and Australian management guidelines. Results: Five Long COVID specific guidelines and sixteen Australian services were reviewed. The majority of Australian services provided multidisciplinary rehabilitation programs with service models generally consistent with international and national guidelines. Most services included physiotherapists and psychologists. While early investigation at week 4 after contraction of COVID-19 is recommended by the Australian, UK and US guidelines, this was not consistently implemented. Conclusion: Besides Long COVID clinics, future solutions should focus on early identification that can be delivered by General Practitioners and all credentialed allied health professions. Study findings highlight an urgent need for innovative care models that address individual patient needs at an affordable cost. We propose a model that focuses on patient-led self-care with further enhancement via multi-disciplinary care tools.

Case report: Right coronary artery to left ventricular fistula complicated with coronary artery dilation presenting as persistent cardiogenic ischemic chest pain

We reported a patient with a fistula of the right coronary artery to the left ventricle, accompanied by dilation of the right coronary artery and persistent chest pain. This patient underwent surgical fistula closure surgery, but the fistula recurred. Persistent chest pain reappeared after encountering COVID-19 infection. We analyzed the mechanism of persistent myocardial ischemic chest pain caused by coronary artery fistula in this patient, the impact of surgery on the patient's disease, the possible mechanism of COVID-19 causing persistent ischemic chest pain in this patient, and the possible mechanism of metoprolol in alleviating myocardial ischemic chest pain in this patient.

Long-Term Symptoms and Quality of Life in Persons with COVID-19

Objective

After three years since the first cases of COVID-19, many people suffer from post-COVID symptoms, reducing their quality of life. In this study, we aimed to evaluate the symptoms and prevalence of long COVID and its effect on the quality of life and also the effect of SARS-CoV-2 vaccine on the quality of life.

Materials and Methods

Patients with COVID-19 between April 01, 2020, and December 31, 2021, were evaluated with a survey at least three and at most 12 months (mean 7.43±3.3 months) after diagnosis. Patients answered the questions face-to-face or via telephone interview. The survey included questionnaires on demographic features, current complaints, and complaints that persisted or developed after recovery, Short Form 36 Health Survey (SF-36), and European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L) Scale.

Results

The study was conducted with 521 participants, 81% complaining of post-COVID symptoms. The most common symptoms were fatigue and shortness of breath. Long COVID was found to significantly reduce the quality of life in both sub-dimensions of the scale. Compared to SF-36 Turkish population norms, all participants showed a significant decrease in quality of life subscales. Vaccination against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was found to improve quality of life and reduce long-term COVID-19 symptoms.

Conclusion

COVID-19 has significantly affected quality of life. Post-illness follow-up of people with COVID-19 is important to provide patients with medical, physical, and psychosocial rehabilitation support. SARS-COV-2 vaccine reduces the negative effects of COVID-19 on quality of life. For this reason, the community should be made aware of vaccination, and COVID-19 vaccination rates should be increased in the community.

Radiological and Functional Pulmonary Evolution in Post-COVID-19 Patients: An Observational Study

COVID-19 has generated a scenario for global health with multiple systemic impairments. This retrospective study evaluated the clinical, radiological, and pulmonary functional evolution in 302 post-COVID-19 patients. Regarding post-COVID-19 pulmonary symptoms, dry cough, dyspnea, and chest pain were the most frequent. Of the associated comorbidities, asthma was more frequent (23.5%). Chest tomography (CT) initially showed a mean pulmonary involvement of 69.7%, and evaluation in the subsequent months showed improvement in the evolutionary image. With less than six months post-pathology, there was a commitment of 37.7% from six to twelve months it was 20%, and after 12 months it was 9.9%. As for most of the sample, 50.3% of the patients presented CT normalization less than six months after infection, 23% were normalized between six and twelve months, and 5.2% presented with normalized images after twelve months, with one remaining. A percentage of 17.3% maintained post-COVID-19 pulmonary residual sequelae. Regarding spirometry, less than six months after pathology, 59.3% of the patients presented regular exam results, 12.3% had their function normalized within six to twelve months, and 6.3% had normal exam results twelve months after their post-pathology evaluation. Only 3.6% of the patients still showed some alteration during this period.

COVID-19 and cognitive performance: a Mendelian randomization study

Background

A substantial proportion of individuals with COVID-19 experienced cognitive impairment after resolution of SARS-CoV-2 infection. We aimed to evaluate whether genetic liability to SARS-CoV-2 infection per se, or more severe COVID-19, is causally linked to cognitive deficit.

Methods

We firstly performed univariable Mendelian randomization (MR) analysis to examine whether genetic liability to SARS-CoV-2 infection, hospitalized and severe COVID-19 is causally associated with cognitive performance. To dissect the causal pathway, multivariable MR (MVMR) analysis was conducted by adjusting for five inflammatory markers [C-reactive protein, interleukin (IL)-1β, IL-6, IL-8, and tumour necrosis factor α, as proxies of systemic inflammation].

Results

In univariable MR analysis, host genetic liability to SARS-CoV-2 infection was associated with lower cognitive performance [inverse variance weighted (IVW) analysis, estimate: -0.023; 95% Confidence Interval (CI): -0.038 to -0.009]. Such causal association was attenuated in MVMR analysis when we adjusted for the five correlated inflammatory markers in one analysis (IVW analysis, estimate: -0.022; 95% CI: -0.049 to 0.004). There was insufficient evidence of association for genetic liability to hospitalized and severe COVID-19 with cognitive performance.

Conclusion

The causal effect of host genetic liability to SARS-CoV-2 infection on reduced cognitive performance may be mediated by systemic inflammation. Future studies examining whether anti-inflammatory agents could alleviate cognitive impairment in SARS-CoV-2-infected individuals are warranted.