[Persistent COVID-19 syndrome. A narrative review]

Single-cell spatiotemporal analysis of the lungs reveals Slamf9+ macrophages involved in viral clearance and inflammation resolution

How the lung achieves immune homeostasis after a pulmonary infection is not fully understood. Here, we analyzed the spatiotemporal changes in the lungs over a 2-week natural recovery from severe pneumonia in a Syrian hamster model of SARS-CoV-2 infection. We find that SARS-CoV-2 infects multiple cell types and causes massive cell death at the early stage, including alveolar macrophages. We identify a group of monocyte-derived Slamf9+ macrophages, which are induced after SARS-CoV-2 infection and resistant to impairment caused by SARS-CoV-2. Slamf9+ macrophages contain SARS-CoV-2, recruit and interact with Isg12+Cst7+ neutrophils to clear the viruses. After viral clearance, Slamf9+ macrophages differentiate into Trem2+ and Fbp1+ macrophages, contributing to inflammation resolution at the late stage, and finally replenish alveolar macrophages. These findings are validated in a SARS-CoV-2-infected hACE2 mouse model and confirmed with publicly available human autopsy single-cell RNA-seq data, demonstrating the potential role of Slamf9+ macrophages and their coordination with neutrophils in post-injury tissue repair and inflammation resolution.

The Association of Genetic Markers Involved in Muscle Performance Responding to Lactate Levels during Physical Exercise Therapy by Nordic Walking in Patients with Long COVID Syndrome: A Nonrandomized Controlled Pilot Study

Several genetic markers have shown associations with muscle performance and physical abilities, but the response to exercise therapy is still unknown. The aim of this study was to test the response of patients with long COVID through an aerobic physical therapy strategy by the Nordic walking program and how several genetic polymorphisms involved in muscle performance influence physical capabilities. Using a nonrandomized controlled pilot study, 29 patients who previously suffered from COVID-19 (long COVID = 13, COVID-19 = 16) performed a Nordic walking exercise therapy program for 12 sessions. The influence of the ACE (rs4646994), ACTN3 (rs1815739), AMPD1 (rs17602729), CKM (rs8111989), and MLCK (rs2849757 and rs2700352) polymorphisms, genotyped by using single nucleotide primer extension (SNPE) in lactic acid concentration was established with a three-way ANOVA (group × genotype × sessions). For ACE polymorphism, the main effect was lactic acid (p = 0.019). In ACTN3 polymorphism, there were no main effects of lactic acid, group, or genotype. However, the posthoc analysis revealed that, in comparison with nonlong COVID, long COVID increased lactic acid concentrations in Nordic walking sessions in CT and TT genotypes (all p < 0.05). For AMPD1 polymorphism, there were main effects of lactic acid, group, or genotype and lactic acid × genotype or lactic acid × group × genotype interactions (all p < 0.05). The posthoc analysis revealed that, in comparison with nonlong COVID, long COVID increased lactic acid concentrations in Nordic walking sessions in CC and CT genotypes (all p < 0.05). Physical therapy strategy through Nordic walking enhanced physical capabilities during aerobic exercise in post-COVID19 patients with different genotypes in ACTN3 c.1729C>T and AMPD1 c.34C>T polymorphisms. These findings suggest that individuals who reported long COVID who presumably exercised less beforehand appeared to be less able to exercise, based on lactate levels, and the effect of aerobic physical exercise enhanced physical capabilities conditioned by several genetic markers in long COVID patients.

Gender differences in symptomatology, socio-demographic information and quality of life in Spanish population with long COVID condition: a cross-sectional study

Introduction

Long COVID patients experience a decrease in their quality of life due to the symptomatology produced by the disease. It is also important to understand how long COVID affects both men and women. The objective of this study is to examine the impact of long COVID symptomatology on the quality of life of Spanish adults from a gender perspective.

Methods

An observational and cross-sectional study was carried out. Participants were able to complete an online questionnaire using an online platform. A sample of 206 people participated in the study.

Results

The 80.6% of the sample were women with a mean age of 46.51 (±8.28) and the 19.4% were men with a mean age of 48.03 (±9.50). The medium score in the PAC19-QoL test was 141.47 (±24.96) and segmented by gender, 141.65 (±23.95) for women and 140.82 (±28.66) for men. The most common symptoms in women were muscle and joint pain (94.6%), fatigue (94.0%), discomfort (92.2%), difficulty concentrating (91.0%), and memory loss (88.6%). For men the symptoms included muscle and joint pain (97.5%) and fatigue (97.5%) both occupying first position, discomfort (92.0%), difficulty concentrating (90.0%), mood disturbances (90.0%), and memory loss (87.5%). The chi-square test showed statistical significance (p < 0.005) for socio-demographic information, quality of life scores, and long COVID symptoms by intensities.

Conclusion

This study shows that there are gender differences in the way that long COVID is experienced.

[Genetic factors associated with long COVID]

INTRODUCTION

The variability in expression and evolution of COVID is not completely explained by clinical factors. In fact, genetic factors play an important role. Moreover, it is unknown whether the genetic factor that contribute to susceptibility and severity are also involved in the onset and evolution of long-COVID. The objective of this review is to gather information from literature to understand which genetic factors are involved in the onset of persistent COVID.

MATERIAL AND METHODS

Systematic review in PubMed and bioRxiv and medRxiv repositories based on MeSH-descriptors and MeSH-terms related to COVID and genetic factors. Using these terms 2715 articles were pooled. An initial screening performed by authors independently, selected 205 articles of interest. A final deeper screening a total of 85 articles were chosen for complete reading and summarized in this review.

RESULTS

Although ACE2 and TMPSS6 are involved in COVID susceptibility, their involvement in long-COVID has not been found. On the other hand, the severity of the disease and the onset of long-COVID has been associated with different genes involved in the inflammatory and immune response. Particularly interesting has been the association found with the FOXP4 locus.

CONCLUSIONS

Although studies on long-COVID are insufficient to fully comprehend the cause, it is clear that the current identified genetic factors do not fully explain the progression and onset of long-COVID. Other factors such as polygenic action, pleiotropic genes, the microbiota and epigenetic changes must be considered and studied.

Functional rehabilitation based on therapeutic exercise training in patients with postacute COVID syndrome (RECOVER)

INTRODUCTION AND OBJECTIVES

Postacute COVID syndrome (PACS) is common after acute SARS-CoV-2 infection. One of the most frequent and disabling symptoms is exercise intolerance (EI). Recent evidence suggests that EI in PACS has a peripheral (metabolic-neuromuscular) origin, suggesting that exercise training may be an effective treatment. The aim of this study was to assess the role a therapeutic physical exercise program (TPEP) in PACS with EI.

METHODS

This single-center, open-label, randomized clinical trial compared an exercise training program (intervention group) with regular physical activity recommendations (control group) in patients with PACS and EI. The intervention group underwent an 8-week TPEP. The primary endpoint was improvement in functional capacity, assessed as the change in peak VO2.

RESULTS

We included 50 participants with PACS (73% women, mean age 47±7.1 years). The intervention group showed a 15% improvement in peak VO2 (peak VO2 pre- and postintervention: 25.5±7.7mL/kg/min and 29.3±4.7 mL/kg/min; P <.001) and a 13.2% improvement in predicted values (92.1±14.3% and 108.4±13.4%; P <.001). No significant changes in VO2 values were observed in the control group. Unlike the control group, the intervention group also showed improvements in all secondary outcomes: quality of life scales, muscle power, maximum inspiratory power, metabolic flexibility, and body fat percentage.

CONCLUSIONS

The program improved functional capacity in patients with PACS and EI.

Enhancing exercise intervention for patients with post-acute COVID-19 syndrome using mobile health technology: The COVIDReApp randomised controlled trial protocol

Objectives

To analyse the effectiveness of a physical exercise programme guided by a mobile health technology system (COVIDReApp) for patients with post-acute COVID-19 syndrome. This syndrome is a multisystem disease that occurs in people with a history of COVID-19 between 1 and 3 months after the onset of the disease. This study will assess the impact of the intervention on fatigue, post-exertional dyspnoea, quality of life, pain severity, physical fitness, anxiety, depression and cognitive function. We also aim to analyse whether there are associations between the variables studied and the evolution of these associations during follow-up.

Design

A single-blind randomised controlled trial.

Methods

One hundred patients diagnosed with post-acute COVID-19 will be enrolled and randomly assigned to two groups. The experimental group will perform the intervention through a physical exercise programme guided by the COVIDReApp system, whereas the control group will perform the programme in paper format. Study outcomes will be collected at baseline and at 4, 12 and 24 weeks. Student's t-tests or Mann-Whitney U-tests will be used to analyse differences between groups, mixed ANOVA for differences over time and longitudinal structural equations for associations between variables at follow-up.

Discussion

This study is based on current evidence regarding exercise prescription recommendations for patients with post-acute COVID-19 syndrome. Our intervention is supported by a solid theoretical framework; however, challenges include tailoring the physical exercise programme to everyone's predominant symptoms and ensuring adherence to the programme.

Trial registration number

NCT05725538.

Factors associated with long COVID syndrome in a Colombian cohort

Introduction

After acute phase of SARS-CoV-2 infection, some patients persist with clinical symptoms, a phenomenon known as Long COVID syndrome. It is necessary to understand the factors associated with the persistence of these symptoms to develop individualized preventive approaches and effectively address this challenge.

Objective

To determine the factors associated with the persistence of symptoms six months after COVID-19 infection.

Materials and methods

A ambidirectional cohort, single-center study, that included individuals previously diagnosed with COVID-19 by real-time polymerase chain reaction (PCR) positive test, who were followed for a period of six months. Univariate, bivariate and a multivariate binomial regression model were performed to determine risk factors associated with the persistence of COVID-19 symptoms at the six months of follow-up.

Results

The prevalence of long COVID syndrome was 47%. Age demonstrated no significant association with Long COVID (RR 0.999 [95% CI 0.996-1.002]); however, female sex (RR 1.148 [95% CI 1.038-1.268]), requirement of mechanical ventilation (RR 1.278 [95% CI 1.050-1.555]), presence of Chronic Obstructive Pulmonary Disease (COPD) (RR 1.340 [95% CI 1.104-1.626]), Rheumatic Disease (RR 1.259 [95% CI 1.055-1.504]) and the Hospitalization Type: General Hospitalization (RR 1.247 [95% CI 1.090-1.427]) and ICU Hospitalization (RR 1.490 [95% CI 1.221-1.818]) were significantly associated with the persistence of symptoms at the six month of follow-up.

Conclusion

Female sex, presence of COPD, rheumatic disease, hospitalization type and requirement of mechanical ventilation during index infection were identified as significant risk factors for the diagnosis of Long COVID. These findings emphasize the importance of addressing Long COVID syndrome in terms of prevention and management, taking these risk factors into consideration.

Dynamics of the Microbiota and Its Relationship with Post-COVID-19 Syndrome

Coronavirus disease (COVID-19) is an infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which can be asymptomatic or present with multiple organ dysfunction. Many infected individuals have chronic alterations associated with neuropsychiatric, endocrine, gastrointestinal, and musculoskeletal symptoms, even several months after disease onset, developing long-COVID or post-acute COVID-19 syndrome (PACS). Microbiota dysbiosis contributes to the onset and progression of many viral diseases, including COVID-19 and post-COVID-19 manifestations, which could serve as potential diagnostic and prognostic biomarkers. This review aimed to discuss the most recent findings on gut microbiota dysbiosis and its relationship with the sequelae of PACS. Elucidating these mechanisms could help develop personalized and non-invasive clinical strategies to identify individuals at a higher risk of experiencing severe disease progression or complications associated with PACS. Moreover, the review highlights the importance of targeting the gut microbiota composition to avoid dysbiosis and to develop possible prophylactic and therapeutic measures against COVID-19 and PACS in future studies.

Sociodemographic and Clinical Profile of Long COVID-19 Patients, and Its Correlation with Medical Leave: A Comprehensive Descriptive and Multicenter Study

The persistent condition of COVID-19 is characterized by a wide range of symptoms that have had a significant impact on both the health status and occupational life of the population. In this observational and multicenter study, the relationship between the sociodemographic and clinical profile of Spanish patients diagnosed with long COVID, and the work-related disability resulting from this pathology was analyzed. The analysis included 689 responses. A descriptive analysis of the variables recorded was performed, together with a bivariate analysis to determine associations between work-related disability and variables such as gender, age, health status, disabling symptoms or comorbidities. The results obtained highlight fatigue and lack of concentration (brain fog) as the most incapacitating symptoms among patients diagnosed with long COVID. Multivariate analysis revealed that time since diagnosis (OR: 0.57, CI95%: 0.36-0.89, p: 0.013), concomitant renal insufficiency (OR: 4.04, CI95%: 1.42-11.4, p: 0.008), and symptoms like fatigue (OR: 0.56, CI95%: 0.33-0.99) and tremors (OR: 2.0, CI95%: 1.06-3.69, p: 0.029), were associated with work-related disability. These findings highlight the need to improve the health and work-related management of this condition in the healthcare system. Besides risk factor control, it is suggested to pay special attention to determining the appropriate timing of medical leave work reintegration, along with coordination between primary care and occupational health services to ensure the gradual and tailored return of patients with long COVID to the workforce.

Considerations of COVID-19 in Ophthalmology

Since its emergence in early 2020, the SARS-CoV-2 infection has had a significant impact on the entire eye care system. Ophthalmologists have been categorized as a high-risk group for contracting the virus due to the belief that the eye may be a site of inoculation and transmission of the SARS-CoV-2 infection. As a result, clinical ophthalmologists, optometrists, and eyecare professionals have had to familiarize themselves with the ocular manifestations of COVID-19, as well as its treatments and vaccines. The implementation of measures to prevent the transmission of the virus, such as restrictions, lockdowns, telemedicine, and artificial intelligence (AI), have led to substantial and potentially irreversible changes in routine clinical practice, education, and research. This has resulted in the emergence of a new mode of managing patients in a routine clinical setting. This brief review aims to provide an overview of various aspects of COVID-19 in ophthalmology, including the ocular manifestations related to the disease, the modes of transmission of SARS-CoV-2 infection, precautions taken in ophthalmic practice to prevent the spread of the virus, drugs, and vaccines used in the treatment of COVID-19, the impact of the pandemic on patients, clinicians, and the eye care system as a whole, and the future of ophthalmology conditioned by this global pandemic experience.

Cognitive functions in COVID-19 survivors, approaches strategies, and impact on health systems: a qualitative systematic review

Post-COVID syndrome has been defined as signs and symptoms that develop after an infection consistent with COVID-19 and continue for more than 12 weeks, including neurocognitive signs and symptoms that have an impact on the functioning and quality of life of middle-aged adult and older survivors. This systematic review describes the current knowledge of long-term cognitive impairments in COVID-19 survivors, approaches strategies, and their impact on public and private health services worldwide. The systematic review was conducted under the criteria and flowchart established in the PRISMA statement, considering studies from the PubMed, Scopus, and Web of Science databases between 2020 and 2023. The included studies considered participants over 40 years of age, COVID-19 survivors. A total of 68 articles were included, most of which had high to excellent quality. The analysis showed the presence of heterogeneous cognitive symptoms in COVID survivors, persistent for at least 12 weeks from the onset of infection, mostly unsystematized and nonspecific approaches strategies, and a lack of methods for monitoring their effectiveness, with a significant economic and logistical impact on health systems. Specific protocols are required for the rehabilitation of persistent cognitive dysfunction in COVID-19 survivors, as well as longitudinal studies to evaluate the effectiveness of these interventions.

Physical Therapies in the Treatment of Post-COVID Syndrome: A Systematic Review

INTRODUCTION

Several days to months after diagnosis of SARS-CoV-2, 35% of patients have persistent symptoms in high incidence. This is referred to as post-COVID-19 Syndrome. There is a pressing need to find a way to help patients with the manifested symptoms.

OBJECTIVE

To show the different therapies that exist for post-COVID Syndrome and their efficacy.

METHODOLOGY

A systematic review of the scientific literature was carried out. The data search was carried out in Scopus, PubMed, Cinahl, and Web of Science. Of the 106 articles found, 12 articles were obtained after applying the following eligibility criteria.

RESULTS

Interventions related to respiratory musculature and moderate intensity exercise both in supervised face-to-face sessions and in supervised home sessions led patients to a significant improvement in the symptoms presented.

CONCLUSION

Physical therapies significantly reduce fatigue and dyspnea as well as other symptoms related to quality of life.

Clinical Characterization of the Persistent COVID-19 Symptoms: A Descriptive Observational Study in Primary Care

INTRODUCTION

Evidence and clinical experience suggest that there are a range of signs of health issues that affect patients who have recovered from acute COVID-19 infection. This condition is commonly referred to as "persistent COVID-19," which is not connected with the severity of the disease. We have identified the prevalence and clinical-epidemiological characteristics of patients with COVID-19 and persistent symptoms treated in primary care centers. This is a descriptive observational study conducted between December 2020 and May 2022, the data were collected from digitized medical records and interviewing 1542 individuals with laboratory-confirmed SARS-CoV-2 infection. These patients were clinically followed for up to 1 year, based on the prevalence of symptoms. When stratifying by the risk of developing persistent COVID-19, 37.09% of the patients exhibited risk factors, with age (over 60 years) and cardiovascular risk factors predominating. The obtained prevalence of persistent COVID-19 at 90 days was 12.39%, with a slight predominance in females (55%) and a mean age of 45.8 years. The most affected systems were the cardiovascular, respiratory, and psychoneurological systems, with predominant symptoms of fatigue (41.88%), dyspnea (32.46%), and headache (14.66%), among others. The average duration of persistent symptoms was 178 days, equivalent to 6 months. In conclusion, over 10% of patients who recover from acute SARS-CoV-2 infection developed long-term consequences.

OBJECTIVE

To measure the prevalence and clinical-epidemiological characteristics of individuals diagnosed with COVID-19 and persistent symptoms treated in primary care centers in Área Sanitaria Sur de Córdoba (Spain) between December 2020 and May 2022.

METHODS

A retrospective observational study of the population of Área Sanitaria Sur de Córdoba was developed between December 2020 and May 2022. The scope of the study was 1542 individuals, and the prevalence of patients diagnosed with COVID-19 and persistent symptoms was determined based on laboratory-confirmed cases, randomly selected from adults who had progressed beyond the acute phase of the disease. All data were managed by the Área Sanitaria Sur de Córdoba (Spain).

RESULTS

The risk factor of exhibiting one or more risk factors associated with developing persistent COVID-19 is 37.09%. The obtained prevalence of persistent COVID-19 at 90 days is 12.39%, it is higher in females (55%) than males and the mean age was 45.8 years. The most affected systems were the cardiovascular, respiratory, and psychoneurological systems, with predominant symptoms of fatigue (41.88%), dyspnea (32.46%), and headache (14.66%), among others.

CONCLUSIONS

Results confirm that more than 10% of individuals recovering from acute SARS-CoV-2 infection showed long-term consequences and the observed persistent symptom duration was 178 days on average.

Burden of disease of COVID-19 in the department of Nariño, Colombia, 2020-2021

OBJECTIVES.

To estimate the burden of disease of COVID-19 in the department of Nariño, Colombia, based on the disability-adjusted life years (DALYs) between March 2020 and August 2021.

MATERIALS AND METHODS.

The description and characterization of COVID-19 cases reported between March 2020 and August 2021 was made according to age groups, sex, ethnicity, municipalities of residence and subregions of Nariño by using information from the national surveillance system SIVIGILA. Crude and cumulative mortality rates for COVID-19 were estimated for the previously described variables. Years lost due to premature death (YLL) and years lived with disability (YLD) were calculated. Total DALYs were estimated by adding YLL + YLD. These were calculated by sex, ethnicity, age group and subregions of Nariño. Relative risks were estimated from rate ratios (RR) and 95% confidence intervals for the study variables.

RESULTS.

The highest morbidity, mortality and DALY rates occurred between February and September 2021, in men, in those older than 70 years, in the Afro-descendant ethnic minority group and in the Central, Obando and Juanambú subregions. The burden of disease of COVID-19 in Nariño during the study period is attributed to the YLL, which explain more than 97% of it.

CONCLUSIONS.

This is one of the first studies on burden of disease at the regional level, carried out in Colombia, that employs a standardized methodology for COVID-19. This measurement would generate estimates that would allow targeting resources in an intersectoral manner, mitigating the damage to specific populations and geographic areas, especially the most vulnerable ones.

Neurocognitive Profile of the Post-COVID Condition in Adults in Catalonia-A Mixed Method Prospective Cohort and Nested Case-Control Study: Study Protocol

The diagnosis of the post-COVID condition is usually achieved by excluding other diseases; however, cognitive changes are often found in the post-COVID disorder. Therefore, monitoring and treating the recovery from the post-COVID condition is necessary to establish biomarkers to guide the diagnosis of symptoms, including cognitive impairment. Our study employs a prospected cohort and nested case-control design with mixed methods, including statistical analyses, interviews, and focus groups. Our main aim is to identify biomarkers (functional and structural neural changes, inflammatory and immune status, vascular and vestibular signs and symptoms) easily applied in primary care to detect cognitive changes in post-COVID cases. The results will open up a new line of research to inform diagnostic and therapeutic decisions with special considerations for cognitive impairment in the post-COVID condition.