Clinical characteristics and outcomes of hospitalized patients with COVID-19 in a city of South Brazil: Have they changed through the first year of the pandemic?

The Coronavirus Disease 2019 (COVID-19) pandemic posed various challenges to the healthcare system and disease management. This study aimed to describe changes in the clinical characteristics and outcomes of hospitalized patients during the first year of the COVID-19 pandemic in a city in southern Brazil. This prospective study was carried out in two tertiary care private hospitals in Curitiba. A total of 1151 patients hospitalized between March 2020 and March 2021 were included. We identified three epidemiological critical periods of the pandemic and compared patients' characteristics and the frequencies of oral intubation, intensive care unit (ICU) admission and mortality. Continuous variables were analyzed by variance analysis model (ANOVA) or the Kruskal-Wallis nonparametric test and categorical variables by the chi-square or Fisher's exact test. Models for univariate and multivariate logistic regression analysis were adjusted to identify the factors associated with mortality. All p-values were two-tailed and p<0.05 was considered statistically significant. The average age of the patients was 58 years and 60.9% (n = 701) were males. The most prevalent comorbidities were systemic arterial hypertension, diabetes and obesity. There were no significant variations in the demographic characteristics and previous comorbidities of the patients for the different periods of analysis. Mortality was positively associated with the age ≥65 years and the presence of one or more cardiometabolic comorbidities (p<0.001). March 2021 was the most important critical period of the pandemic since there were higher frequencies of patients admitted later in the course of the disease, with desaturation and more symptoms at hospital admission (p<0.001). There was also an increase in the duration of hospital stay (p<0.001) and the frequencies of all critical outcomes for this period: oral intubation (p<0.001), ICU admission (p = 0.606) and mortality (p = 0.001). Our key findings revealed that, although there were no statistically significant differences between the subgroups of hospitalized patients over time in terms of demographic characteristics and comorbidities, the course of COVID-19 was significantly more severe for patients admitted to the hospital at the end of the first year of the pandemic in Brazil.

Deregulated miRNA expression is associated with endothelial dysfunction in post-mortem lung biopsies of COVID-19 patients.

MicroRNAs (miRNAs) are critical modulators of endothelial homeostasis, which highlights their involvement in vascular diseases, including the ones caused by virus infections. Our main objective was to identify miRNAs involved in the endothelial function and determine their expression in post-mortem lung biopsies of COVID-19 patients with severe respiratory injuries and thrombotic events. Based on functional enrichment analysis, miR-26a-5p, miR-29b-3p, and miR-34a-5p were identified as regulators of mRNA targets involved in endothelial, and inflammatory signaling pathways as well as in viral diseases. A miRNA/mRNA network, constructed based on protein-protein interactions of the miRNA targets and the inflammatory biomarkers characterized in the patients, revealed a close interconnection of these miRNAs with relevance to the endothelial activation/dysfunction. Reduced expression levels of selected miRNAs were observed in the lung biopsies of COVID-19 patients (n=9) compared to the Controls (n=10)(P<0.01-0.0001). MiR-26a-5p and miR-29b-3p presented the best power to discriminate these groups (AUC=0.8286, and AUC=0.8125, respectively). The correlation analysis of the miRNAs with inflammatory biomarkers in the COVID-19 patients was significant for miR-26a-5p [IL-6 (r2=0.5414), and ICAM-1(r2=0.5624)], and miR-29b-3p [IL-4 (r2=0.8332), and IL-8 (r2=0.2654)]. Altogether, these findings demonstrate the relevance and the non-random involvement of miR-26a-5p, miR-29b-3p, and miR-34a-5p in endothelial dysfunction and inflammatory response in patients with SARS-CoV-2 infection and the occurrence of severe lung injury and immunothrombosis.

Aging and the COVID-19 pandemic: The inter-related roles of biology, physical wellbeing, social norms and global health systems.

The coronavirus disease 2019 (COVID-19) pandemic has had a devastating and disproportionate impact on the elderly population. As the virus has swept through the world, already vulnerable elderly populations worldwide have faced a far greater burden of deaths and severe disease, crippling isolation, widespread societal stigma, and wide-ranging practical difficulties in maintaining access to basic health care and social services - all of which have had significant detrimental effects on their mental and physical wellbeing. In this paper, we present an overview of aging and COVID-19 from the interrelated perspectives of underlying biological mechanisms, physical manifestations, societal aspects, and health services related to the excess risk observed among the elderly population. We conclude that to tackle future pandemics in an efficient manner, it is essential to reform national health systems and response strategies from an age perspective. As the global population continues to age, elderly-focused health services should be integrated into the global health systems and global strategies, especially in low- and middle-income countries with historically underfunded public health infrastructure and insufficient gerontological care.

Transcriptomic profiling of cardiac tissues from SARS-CoV-2 patients identifies DNA damage.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to present with pulmonary and extra-pulmonary organ complications. In comparison with the 2009 pandemic (pH1N1), SARS-CoV-2 infection is likely to lead to more severe disease, with multi-organ effects, including cardiovascular disease. SARS-CoV-2 has been associated with acute and long-term cardiovascular disease, but the molecular changes that govern this remain unknown. In this study, we investigated the host transcriptome landscape of cardiac tissues collected at rapid autopsy from seven SARS-CoV-2, two pH1N1, and six control patients using targeted spatial transcriptomics approaches. Although SARS-CoV-2 was not detected in cardiac tissue, host transcriptomics showed upregulation of genes associated with DNA damage and repair, heat shock, and M1-like macrophage infiltration in the cardiac tissues of COVID-19 patients. The DNA damage present in the SARS-CoV-2 patient samples, were further confirmed by γ-H2Ax immunohistochemistry. In comparison, pH1N1 showed upregulation of interferon-stimulated genes, in particular interferon and complement pathways, when compared with COVID-19 patients. These data demonstrate the emergence of distinct transcriptomic profiles in cardiac tissues of SARS-CoV-2 and pH1N1 influenza infection supporting the need for a greater understanding of the effects on extra-pulmonary organs, including the cardiovascular system of COVID-19 patients, to delineate the immunopathobiology of SARS-CoV-2 infection, and long term impact on health.

Lung Inflammasome Activation in SARS-CoV-2 Post-Mortem Biopsies.

The inflammasome complex is a key part of chronic diseases and acute infections, being responsible for cytokine release and cell death mechanism regulation. The SARS-CoV-2 infection is characterized by a dysregulated cytokine release. In this context, the inflammasome complex analysis within SARS-CoV-2 infection may prove beneficial to understand the disease's mechanisms. Post-mortem minimally invasive autopsies were performed in patients who died from COVID-19 (n = 24), and lung samples were compared to a patient control group (n = 11) and an Influenza A virus H1N1 subtype group from the 2009 pandemics (n = 10). Histological analysis was performed using hematoxylin-eosin staining. Immunohistochemical (IHC) staining was performed using monoclonal antibodies against targets: ACE2, TLR4, NF-κB, NLRP-3 (or NALP), IL-1ß, IL-18, ASC, CASP1, CASP9, GSDMD, NOX4, TNF-α. Data obtained from digital analysis underwent appropriate statistical tests. IHC analysis showed biomarkers that indicate inflammasome activation (ACE2; NF-κB; NOX4; ASC) were significantly increased in the COVID-19 group (p < 0.05 for all) and biomarkers that indicate cell pyroptosis and inflammasome derived cytokines such as IL-18 (p < 0.005) and CASP1 were greatly increased (p < 0.0001) even when compared to the H1N1 group. We propose that the SARS-CoV-2 pathogenesis is connected to the inflammasome complex activation. Further studies are still warranted to elucidate the pathophysiology of the disease.

COVID-19 Outcome Relates With Circulating BDNF, According to Patient Adiposity and Age.

Background and Aims: We evaluated adipose tissue-derived hormones, body composition, serum metabolic profile, levels of brain-derived neurotrophic factor (BDNF), and the association of these parameters with the clinical outcome in patients with COVID-19. We sought to examine whether obesity, sex, and age influence the adipose tissue endocrine response to the disease. Methods: This prospective study investigated 145 hospitalized patients with COVID-19. Patients were categorized based on their body mass index (BMI), sex and age, and were also classified regarding their outcome after hospitalization as: (a) Non-ICU: patients hospitalized who did not receive intensive care; (b) ICU-survivor: patients admitted to the intensive care unit and discharged; (c) ICU-death: patients who died. Blood samples were collected by the hospital staff between the first and third day of hospitalization. Serum leptin, adiponectin and BDNF concentrations, triglycerides, total cholesterol and cholesterol fractions were performed following the manufacturer's guidelines. Results: We demonstrate that BDNF levels predict intensive care (IC) need (p < 0.01). This association was found to be stronger in patients >60y (p = 0.026). Neither leptin nor adiponectin concentration was associated with IC requirement or with patient's outcome, while the BDNF/adiponectin ratio was closely associated with worsened outcomes (p < 0.01). BDNF concentration was similar between sexes, however tended to be lower in male patients (p = 0.023). In older patients, BDNF concentration was lower than that of younger patients (p = 0.020). These age and sex-specific differences should be considered when employing these potential markers for prognosis assessment. While appetite and body composition regulating hormones secreted by the white adipose tissue are not reliable predictors of disease severity, the ratio BDNF/adiponectin was indicative of patient status. Conclusion: Thus, we propose that serum BDNF content and BDNF/adiponectin ratio may serve as tools predicting worsened prognosis in COVID-19, especially for male patients.

The Pathogenesis of COVID-19 Myocardial Injury: An Immunohistochemical Study of Postmortem Biopsies.

Rationale: Myocardial injury associates significantly and independently with mortality in COVID-19 patients. However, the pathogenesis of myocardial injury in COVID-19 remains unclear, and cardiac involvement by SARS-CoV-2 presents a major challenge worldwide. Objective: This histological and immunohistochemical study sought to clarify the pathogenesis and propose a mechanism with pathways involved in COVID-19 myocardial injury. Methods and Results: Postmortem minimally invasive autopsies were performed in six patients who died from COVID-19, and the myocardium samples were compared to a control group (n=11). Histological analysis was performed using hematoxylin-eosin and toluidine blue staining. Immunohistochemical (IHC) staining was performed using monoclonal antibodies against targets: caspase-1, caspase-9, gasdermin-d, ICAM-1, IL-1ß, IL-4, IL-6, CD163, TNF-α, TGF-ß, MMP-9, type 1 and type 3 collagen. The samples were also assessed for apoptotic cells by TUNEL. Histological analysis showed severe pericardiocyte interstitial edema and higher mast cells counts per high-power field in all COVID-19 myocardium samples. The IHC analysis showed increased expression of caspase-1, ICAM-1, IL-1ß, IL-6, MMP-9, TNF-α, and other markers in the hearts of COVID-19 patients. Expression of caspase-9 did not differ from the controls, while gasdermin-d expression was less. The TUNEL assay was positive in all the COVID-19 samples supporting endothelial apoptosis. Conclusions: The pathogenesis of COVID-19 myocardial injury does not seem to relate to primary myocardiocyte involvement but to local inflammation with associated interstitial edema. We found heightened TGF-ß and interstitial collagen expression in COVID-affected hearts, a potential harbinger of chronic myocardial fibrosis. These results suggest a need for continued clinical surveillance of patients for myocardial dysfunction and arrythmias after recovery from the acute phase of COVID-19.

Profiling of lung SARS-CoV-2 and influenza virus infection dissects virus-specific host responses and gene signatures.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which emerged in late 2019 has spread globally, causing a pandemic of respiratory illness designated coronavirus disease 2019 (COVID-19). A better definition of the pulmonary host response to SARS-CoV-2 infection is required to understand viral pathogenesis and to validate putative COVID-19 biomarkers that have been proposed in clinical studies. METHODS: Here, we use targeted transcriptomics of formalin-fixed paraffin-embedded tissue using the NanoString GeoMX platform to generate an in-depth picture of the pulmonary transcriptional landscape of COVID-19, pandemic H1N1 influenza and uninfected control patients. RESULTS: Host transcriptomics showed a significant upregulation of genes associated with inflammation, type I interferon production, coagulation and angiogenesis in the lungs of COVID-19 patients compared to non-infected controls. SARS-CoV-2 was non-uniformly distributed in lungs (emphasising the advantages of spatial transcriptomics) with the areas of high viral load associated with an increased type I interferon response. Once the dominant cell type present in the sample, within patient correlations and patient-patient variation, had been controlled for, only a very limited number of genes were differentially expressed between the lungs of fatal influenza and COVID-19 patients. Strikingly, the interferon-associated gene IFI27, previously identified as a useful blood biomarker to differentiate bacterial and viral lung infections, was significantly upregulated in the lungs of COVID-19 patients compared to patients with influenza. CONCLUSION: Collectively, these data demonstrate that spatial transcriptomics is a powerful tool to identify novel gene signatures within tissues, offering new insights into the pathogenesis of SARS-COV-2 to aid in patient triage and treatment.

Lung Neutrophilic Recruitment and IL-8/IL-17A Tissue Expression in COVID-19.

The new SARS-CoV-2 virus differs from the pandemic Influenza A virus H1N1 subtype (H1N1pmd09) how it induces a pro-inflammatory response in infected patients. This study aims to evaluate the involvement of SNPs and tissue expression of IL-17A and the neutrophils recruitment in post-mortem lung samples from patients who died of severe forms of COVID-19 comparing to those who died by H1N1pdm09. Twenty lung samples from patients SARS-CoV-2 infected (COVID-19 group) and 10 lung samples from adults who died from a severe respiratory H1N1pdm09 infection (H1N1 group) were tested. The tissue expression of IL-8/IL-17A was identified by immunohistochemistry, and hematoxylin and eosin (H&E) stain slides were used for neutrophil scoring. DNA was extracted from paraffin blocks, and genotyping was done in real time-PCR for two IL17A target polymorphisms. Tissue expression increasing of IL-8/IL-17A and a higher number of neutrophils were identified in samples from the H1N1 group compared to the COVID-19 group. The distribution of genotype frequencies in the IL17A gene was not statistically significant between groups. However, the G allele (GG and GA) of rs3819025 was correlated with higher tissue expression of IL-17A in the COVID-19 group. SARS-CoV-2 virus evokes an exacerbated response of the host's immune system but differs from that observed in the H1N1pdm09 infection since the IL-8/IL-17A tissue expression, and lung neutrophilic recruitment may be decreased. In SNP rs3819025 (G/A), the G allele may be considered a risk allele in the patients who died for COVID-19.

Susceptibility of the patients infected with Sars-Cov2 to oxidative stress and possible interplay with severity of the disease.

Several recent reviews have suggested a role of oxidative stress in the pathophysiology of COVID-19, but its interplay with disease severity has not been revealed yet. In the present study, we aimed to investigate the association between the severity of COVID-19 and oxidative stress parameters. Clinical data of 77 patients with COVID-19 admitted to the hospital were analyzed and divided into moderate (n = 44) and severe (n = 33) groups based on their clinical condition. Production of oxidant (hydrogen peroxide) and defense antioxidants (total antioxidant capacity, reduced and oxidized glutathione, glutathione s-transferase), and oxidative damage (malondialdehyde, carbonyl, and sulfhydryl) were assessed using the serum samples. The results revealed that severe patients who presented high serum leukocyte count and CRP level stayed for a longer period in the hospital. However, there was no correlation observed between the oxidative stress parameters and degree of COVID-19 severity in the present study. In conclusion, these results indicate that the disease severity may not be a detrimental factor contributing to the changes in the redox profile of hospitalized patients with COVID-19.

Covid-19 cytokine storm in pulmonary tissue: Anatomopathological and immunohistochemical findings.

The COVID-19 pandemic is a worldwide threat, and information on physiopathological aspects of the disease is limited. Despite efforts in searching treatment options, a better understanding of the SARS-CoV-2 pathways can contribute to managing severe cases. In this study, we aim to describe pathological and immunopathogenic findings of two different cases, both in the high-risk group. Post-mortem lung biopsies were analyzed by traditional and immunohistochemical methods. Tissue expression of innate and adaptive immune response biomarkers was tested. We observed a higher innate response in case 1 with an abundance of mast cells, scarce CD8+ lymphocytes, high expression of TNF-alpha, and almost absent adaptative immune response. In case 2, the adaptative immune response was present, with numerous CD8+ lymphocytes and higher levels of IL-4 and TGF-beta. Both cases converged to a prothrombotic state expressing high IL-6, followed by ICAM-1 expression and endotheliites leading to systemic inflammatory response syndrome. In conclusion, differences in age and comorbidities and immune response described here may be related to the SARS-CoV-2 delay in the adaptative immune response, evolution stage of diffuse alveolar damage, and progression for systemic inflammatory response syndrome.

Mast Cells in Alveolar Septa of COVID-19 Patients: A Pathogenic Pathway That May Link Interstitial Edema to Immunothrombosis.

It is currently believed that innate immunity is unable to prevent the spread of SARS-CoV-2 from the upper airways to the alveoli of high-risk groups of patients. SARS-CoV-2 replication in ACE-2-expressing pneumocytes can drive the diffuse alveolar injury through the cytokine storm and immunothrombosis by upregulating the transcription of chemokine/cytokines, unlike several other respiratory viruses. Here we report histopathology data obtained in post-mortem lung biopsies of COVID-19, showing the increased density of perivascular and septal mast cells (MCs) and IL-4-expressing cells (n = 6), in contrast to the numbers found in pandemic H1N1-induced pneumonia (n = 10) or Control specimens (n = 10). Noteworthy, COVID-19 lung biopsies showed a higher density of CD117+ cells, suggesting that c-kit positive MCs progenitors were recruited earlier to the alveolar septa. These findings suggest that MC proliferation/differentiation in the alveolar septa might be harnessed by the shift toward IL-4 expression in the inflamed alveolar septa. Future studies may clarify whether the fibrin-dependent generation of the hyaline membrane, processes that require the diffusion of procoagulative plasma factors into the alveolar lumen and the endothelial dysfunction, are preceded by MC-driven formation of interstitial edema in the alveolar septa.

IFN-γ is an independent risk factor associated with mortality in patients with moderate and severe COVID-19 infection.

BACKGROUND: Innate and adaptive immune responses have been evaluated in infected patients with COVID-19. The severity of the disease has been supposed to be associated with some profile not reported with other bacterial and viral pneumonia. We proposed a study in patients with moderate to severe COVID-19 infection to evaluate the interleukin patterns and its role as prognosis factors. METHODS: A prospective cohort with moderate and severe cases of COVID-19 infection from June to July 2020. Blood samples from patients were collected regularly to evaluate IFN-γ, TNF-α, IL-4, IL-6, and IL-10. Clinical, laboratory, radiological data, and outcomes were recorded. The outcome variable was in-hospital death, survival, mechanical ventilation, and admission at the intensive care unit. Data are presented in median and interquartile range [IQR]. RESULTS: We evaluated the Th1 and Th2 responses according to evolution, distinguishing possible predictive markers. The IFN-γ median of 323 pg/mL [IQR 166-570] was found in patients who died and 208 pg/mL [IQR 155-392] in the survival group (p = 0.017). IFN-γ was also higher in the early stages of the disease (394 pg/mL [IQR 229-575] against 162 pg/mL [IQR 117-259], p < 0.001). IL-4 that was increased in late-stage (182 pg/mL [IQR 162-199] against 131 pg/mL [IQR 124-152], p < 0.001) but not associated with mortality. Also, death was also related to male gender (relative risk = 1.5 [95 % confidence interval = 1.1-2.0]). CONCLUSION: Our results suggest that the activation of the host immune response between Th1 or Th2 in COVID-19 infection may be related to the final result between discharge or death. This implies an attempt to control cytokines, such as IFN-γ, with combined therapies for clinical treatment.

Physical health-related quality of life at higher achieved hemoglobin levels among chronic kidney disease patients: a systematic review and meta-analysis

BACKGROUND: The impact of anemia treatment with erythropoietin stimulating agents (ESA) on health-related quality of life (HRQOL) in chronic kidney disease (CKD) patients is controversial, particularly regarding optimal hemoglobin (Hb) target ranges. METHODS: We conducted a systematic review and meta-analysis of observational studies and randomized controlled trials (RCT) with ESA to estimate the effect of different achieved Hb values on physical HRQOL and functionality. We searched PubMed, EMBASE, CENTRAL, PEDro, PsycINFO and Web of Science databases, until May 2020. Two authors independently extracted data from studies. We included observational and RCTs that enrolled CKD patients undergoing anemia treatment with ESA with different achieved Hb levels among groups. We excluded studies with achieved Hb <9 g/dL. For the meta-analysis, we included RCTs with control groups achieving Hb 10-11.5 g/dL and active groups with Hb >11.5 g/dL. We analyzed the standardized mean difference (SMD) between groups for physical HRQOL. RESULTS: Among 8496 studies, fifteen RCTs and five observational studies were included for the systematic review. We performed the meta-analysis in a subset of eleven eligible RCTs. For physical role and physical function, SMDs were 0.0875 [95% CI: - 0.0025 - 0.178] and 0.08 [95% CI: - 0.03 - 0.19], respectively. For fatigue, SMD was 0.16 [95% CI: 0.09-0.24]. Subgroup analysis showed that trials with greater achieved Hb had greater pooled effects sizes - 0.21 [95% CI: 0.07-0.36] for Hb > 13 g/dL vs. 0.09 [95% CI: 0.02-0.16] for Hb 11.5-13 g/dL. Proportion of older and long-term diabetic patients across studies were associated with lower effect sizes. CONCLUSION: Achieved hemoglobin higher than currently recommended targets may be associated with small but potentially clinically significant improvement in fatigue, but not in physical role or physical function. Younger and non-diabetic patients may experience more pronounced benefits of higher Hb levels after treatment with ESAs.