Thrombotic Events in COVID-19 Are Associated With a Lower Use of Prophylactic Anticoagulation Before Hospitalization and Followed by Decreases in Platelet Reactivity

Asthma and COPD as co-morbidities in patients hospitalised with Covid-19 disease: a global systematic review and meta-analysis

BACKGROUND

Factors predisposing to increased mortality with COVID-19 infection have been identified as male sex, hypertension, obesity, and increasing age. Early studies looking at airway diseases gave some contradictory results. The purpose of our study was to determine global variation in studies in patients hospitalized with COVID-19 in the prevalence of COPD and asthma; and to determine whether the presence of asthma or COPD affected mortality in the same hospital population.

METHODS

A systematic review and meta-analysis of the published literature of COPD and asthma as co-morbidities in patients hospitalized with COVID-19 was performed, looking firstly at the prevalence of these diseases in patients hospitalized with COVID-19, and secondly at the relative risk of death from any cause for patients with asthma or COPD.

RESULTS

Prevalence of both airway diseases varied markedly by region, making meaningful pooled global estimates of prevalence invalid and not of clinical utility. For individual studies, the interquartile range for asthma prevalence was 4.21 to 12.39%, and for COPD, 3.82 to 11.85%. The relative risk of death with COPD for patients hospitalized with COVID-19 was 1.863 (95% CI 1.640-2.115), while the risk with asthma was 0.918 (95% CI 0.767 to 1.098) with no evidence of increased mortality.

CONCLUSIONS

For asthma and COPD, prevalence in patients hospitalized with COVID-19 varies markedly by region. We found no evidence that asthma predisposed to increased mortality in COVID-19 disease. For COPD, there was clear evidence of an association with increased mortality.

TRIAL REGISTRATION

The trial was registered with PROSPERO: registration number CRD42021289886.

Galectin-3 as a Marker for Increased Thrombogenicity in COVID-19

Galectin-3 is a beta-galactoside-binding lectin involved in inflammation and lung fibrosis and postulated to enhance thrombosis. In COVID-19, it is considered to be a prognostic marker of severity. The aim of this study was to evaluate whether galectin-3 is associated with thrombogenicity in COVID-19. Patients with moderate-to-severe COVID-19 (COVpos; n = 55) and patients with acute respiratory diseases, but without COVID-19 (COVneg; n = 35), were included in the study. We measured the amount of galectin-3, as well as other platelet and coagulation markers, and correlated galectin-3 levels with these markers of thrombogenicity and with the SOFA Score values. We found that galectin-3 levels, as well as von Willebrand Factor (vWF), antithrombin and tissue plasminogen activator levels, were higher in the COVpos than they were in the COVneg cohort. Galectin-3 correlated positively with vWF, antithrombin and D-dimer in the COVpos cohort, but not in the COVneg cohort. Moreover, galactin-3 correlated also with clinical disease severity, as measured by the SOFA Score. In patients with acute respiratory diseases, galectin-3 can be considered as a marker not only for disease severity, but also for increased hypercoagulability. Whether galectin-3 might be a useful therapeutic target in COVID-19 needs to be assessed in future studies.

Mortality and Deep Vein Thrombosis in the Gamma Variant of Covid 19 and Lung Injury

PURPOSE

The SARS-CoV-2 disease predisposes infected individuals to thrombosis, the underlying mechanisms of which are not fully understood. The balance between pro-coagulant factors and natural coagulation inhibitors in critically ill patients with Covid-19 is fundamental to the prevention and treatment of complications. The aim of the present study was to investigate the pulmonary injury patterns in Covid-19 having higher mortality in the presence of deep vein thrombosis in comparison to patients without venous thrombosis and determine the Gamma variant.

METHODS

A retrospective study was conducted involving the evaluation of 200 medical records of patients with Covid-19 and a clinical suspicion of deep vein thrombosis (DVT) at the intensive care unit of a public hospital. The sample was divided into two groups of patients were formed - those positive and those negative for DVT. Statistical analysis involved the use of Fisher's exact test, the paired t-test and chi-square test.

RESULTS

Patients with DVT had more severe lung injuries (greater than 70%) compared to those without DVT (p = 0.003). Lesions affecting 50% to 70% of the lung area occurred in little more half of the group with DVT and just under half in the group without DVT (p = 0.5). Pulmonary lesions affecting less than 50% of the lung occurred more in patients without DVT (p = 0.0001). The Gamma variant increased prevalence of the both DVT and mortality (p=0.0001).

CONCLUSION

Deep vein thrombosis is an aggravating factor of mortality in patients with SARS-CoV-2, and the Gamma variant is an aggravating factor of both thrombotic events and mortality.

Platelet activation and partial desensitization are associated with viral xenophagy in patients with severe COVID-19

During severe COVID-19, platelets get activated and become partly desensitized through mechanisms involving glycoprotein shedding.

Platelets from patients with severe COVID-19 internalize SARS-CoV-2 and develop viral xenophagy.

Mild thrombocytopenia, changes in platelet gene expression, enhanced platelet functionality, and presence of platelet-rich thrombi in the lung have been associated with thromboinflammatory complications of patients with COVID-19. However, whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) gets internalized by platelets and directly alters their behavior and function in infected patients remains elusive. Here, we investigated platelet parameters and the presence of viral material in platelets from a prospective cohort of 29 patients with severe COVID-19 admitted to an intensive care unit. A combination of specific assays, tandem mass spectrometry, and flow cytometry indicated high levels of protein and lipid platelet activation markers in the plasma from patients with severe COVID-19 associated with an increase of proinflammatory cytokines and leukocyte-platelets interactions. Platelets were partly desensitized, as shown by a significant reduction of αIIbβ3 activation and granule secretion in response to stimulation and a decrease of surface GPVI, whereas plasma from patients with severe COVID-19 potentiated washed healthy platelet aggregation response. Transmission electron microscopy indicated the presence of SARS-CoV-2 particles in a significant fraction of platelets as confirmed by immunogold labeling and immunofluorescence imaging of Spike and nucleocapsid proteins. Compared with platelets from healthy donors or patients with bacterial sepsis, platelets from patients with severe COVID-19 exhibited enlarged intracellular vesicles and autophagolysosomes. They had large LC3-positive structures and increased levels of LC3II with a co-localization of LC3 and Spike, suggesting that platelets can digest SARS-CoV-2 material by xenophagy in critically ill patients. Altogether, these data show that during severe COVID-19, platelets get activated, become partly desensitized, and develop a selective autophagy response.

The Impact of Prior Antithrombotic use on Thromboembolic Events in Patients with Cardiovascular Disease and Severe COVID-19 Infection

OBJECTIVE

Our objective in this study was to determine the predictive factors of thromboembolic complications in patients with previous heart disease and severe covid-19 infection and the impact of previous use of antithrombotics on protection against these complications.

METHODS

We conducted a single-center retrospective study of 158 patients with heart disease admitted to an intensive care unit for severe SARS-COV-2 infection. In order to determine the predictive factors, we used logistic regression analysis.

RESULTS

Out of 158 patients, 22 were complicated by a thrombo-embolic event (13.9%), mean age of our population 64.03 (SD = 15.27), with a male predominance of 98 (62%). For the predictive factors of thromboembolic complications, and after multivariate analysis, we find the short duration of hospitalization (OR = 0.92; 95%CI (0.863-0.983), P = .014, previous use of antithrombotic drugs ((OR = 0.288, 95%CI (0.091-0.911), P = .034 for antiplatelet agents) and (OR = 0.322, 95% CI (0, 131-0.851), P = .021) for anticoagulants) as protective factors, and admission thrombocytosis as a risk factor (OR = 4.58, 95%CI (1.2-10.627), P = .021). D-dimer was not detected as a risk factor, and this can be explained by the characteristics of our population. Although prior use of antithrombotic drugs protects against thromboembolic complications during severe infection, there was no benefit in mortality.

CONCLUSION

Prior use of antithrombotic drugs is a protective factor against thromboembolic complications in patients with a history of heart disease but without effect on mortality.

Platelet Surface Protein Expression and Reactivity upon TRAP Stimulation after BNT162b2 Vaccination

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces a coagulopathy characterized by platelet activation and a hypercoagulable state with an increased incidence of cardiovascular events. The viral spike protein S has been reported to enhance thrombosis formation, stimulate platelets to release procoagulant factors, and promote the formation of platelet-leukocyte aggregates even in absence of the virus. Although SARS-CoV-2 vaccines induce spike protein overexpression to trigger SARS-CoV-2-specific immune protection, thrombocyte activity has not been investigated in this context. Here, we provide the first phenotypic platelet characterization of healthy human subjects undergoing BNT162b2 vaccination. Using mass cytometry, we analyzed the expression of constitutive transmembrane receptors, adhesion proteins, and platelet activation markers in 12 healthy donors before and at five different time points within 4 weeks after the first BNT162b2 administration. We measured platelet reactivity by stimulating thrombocyte activation with thrombin receptor-activating peptide. Activation marker expression (P-selectin, LAMP-3, LAMP-1, CD40L, and PAC-1) did not change after vaccination. All investigated constitutive transmembrane proteins showed similar expressions over time. Platelet reactivity was not altered after BNT162b2 administration. Activation marker expression was significantly lower compared with an independent cohort of mild symptomatic COVID-19 patients analyzed with the same platform. This study reveals that BNT162b2 administration does not alter platelet protein expression and reactivity.

The Role of P-Selectin in COVID-19 Coagulopathy: An Updated Review

In severe COVID-19, which is characterized by blood clots and neutrophil-platelet aggregates in the circulating blood and different tissues, an increased incidence of cardiovascular complications and venous thrombotic events has been reported. The inflammatory storm that characterizes severe infections may act as a driver capable of profoundly disrupting the complex interplay between platelets, endothelium, and leukocytes, thus contributing to the definition of COVID-19-associated coagulopathy. In this frame, P-selectin represents a key molecule expressed on endothelial cells and on activated platelets, and contributes to endothelial activation, leucocyte recruitment, rolling, and tissue migration. Briefly, we describe the current state of knowledge about P-selectin involvement in COVID-19 pathogenesis, its possible use as a severity marker and as a target for host-directed therapeutic intervention.