Risk of thrombocytopenia and thromboembolism after covid-19 vaccination and SARS-CoV-2 positive testing: self-controlled case series study

Synergistic Effect of SARS-CoV-2 Infection and COVID-19 Vaccination on the Risk of Venous Thromboembolism

BACKGROUND

Previous studies have reported a greater risk of venous thromboembolism among patients infected with SARS-CoV-2 and those who received COVID-19 vaccination. Nevertheless, there is a lack of understanding regarding the interaction effect on the risk of venous thromboembolism occurrence between SARS-CoV-2 infection and COVID-19 vaccination.

METHODS

This was a retrospective cohort study including adult patients with confirmed SARS-CoV-2 infection between October 2020 and September 2021. Patients with confirmed SARS-CoV-2 infection were selected and matched 1:1 by age and sex with individuals who were not infected during the same period. A Cox proportional hazards model was used to analyze the venous thromboembolism risk.

RESULTS

The study included 422546 individuals who were divided into 4 groups; the interaction group defined by having SARS-CoV-2 infection within 90 days following COVID-19 vaccination, the infection group defined by no vaccination before 90 days of SARS-CoV-2 infection, the vaccination group defined by COVID-19 vaccination without SARS-CoV-2 infection, and the reference group defined by neither COVID-19 vaccination nor SARS-CoV-2 infection. The results showed that the adjusted hazard ratio (aHR) of the interaction group was 29.71 (95% confidence interval [CI], 22.95-38.47), while the aHRs of the infection group and the vaccination group were 6.66 (95% CI, 5.18-8.58) and 2.31 (95% CI, 1.78-3.00), respectively.

CONCLUSIONS

A synergistic effect on the risk of venous thromboembolism was suggested when individuals were infected with SARS-CoV-2 within 90 days following COVID-19 vaccination.

Effectiveness of the Original Monovalent Messenger RNA Coronavirus Disease 2019 (COVID-19) Vaccination Series Against Hospitalization for COVID-19-Associated Venous Thromboembolism

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a strong risk factor for venous thromboembolism (VTE). Few studies have evaluated the effectiveness of COVID-19 vaccination in preventing hospitalization for COVID-19 with VTE.

METHODS

Adults hospitalized at 21 sites between March 2021 and October 2022 with symptoms of acute respiratory illness were assessed for COVID-19, completion of the original monovalent messenger RNA (mRNA) COVID-19 vaccination series, and VTE. Prevalence of VTE was compared between unvaccinated and vaccinated patients with COVID-19. The vaccine effectiveness (VE) in preventing COVID-19 hospitalization with VTE was calculated using a test-negative design. The VE was also stratified by predominant circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant.

RESULTS

Among 18 811 patients (median age [interquartile range], 63 [50-73] years; 49% women; 59% non-Hispanic white, 20% non-Hispanic black, and 14% Hispanic; and median of 2 comorbid conditions [interquartile range, 1-3]), 9792 were admitted with COVID-19 (44% vaccinated), and 9019 were test-negative controls (73% vaccinated). Among patients with COVID-19, 601 had VTE diagnosed by hospital day 28, of whom 170 were vaccinated. VTE was more common among unvaccinated than vaccinated patients with COVID-19 (7.8% vs 4.0%; P = .001). The VE against COVID-19 hospitalization with VTE was 84% overall (95% confidence interval, 80%-87%), and VE stratified by predominant circulating variant was 88% (73%-95%) for Alpha, 93% (90%-95%) for Delta, and 68% (58%-76%) for Omicron variants.

CONCLUSIONS

Vaccination with the original monovalent mRNA series was associated with a decrease in COVID-19 hospitalization with VTE, though data detailing prior history of VTE and use of anticoagulation were not available. These findings will inform risk-benefit considerations for those considering vaccination.

Acute respiratory distress syndrome (ARDS): from mechanistic insights to therapeutic strategies

Acute respiratory distress syndrome (ARDS) is a clinical syndrome of acute hypoxic respiratory failure caused by diffuse lung inflammation and edema. ARDS can be precipitated by intrapulmonary factors or extrapulmonary factors, which can lead to severe hypoxemia. Patients suffering from ARDS have high mortality rates, including a 28-day mortality rate of 34.8% and an overall in-hospital mortality rate of 40.0%. The pathophysiology of ARDS is complex and involves the activation and dysregulation of multiple overlapping and interacting pathways of systemic inflammation and coagulation, including the respiratory system, circulatory system, and immune system. In general, the treatment of inflammatory injuries is a coordinated process that involves the downregulation of proinflammatory pathways and the upregulation of anti-inflammatory pathways. Given the complexity of the underlying disease, treatment needs to be tailored to the problem. Hence, we discuss the pathogenesis and treatment methods of affected organs, including 2019 coronavirus disease (COVID-19)-related pneumonia, drowning, trauma, blood transfusion, severe acute pancreatitis, and sepsis. This review is intended to provide a new perspective concerning ARDS and offer novel insight into future therapeutic interventions.

Unraveling Cardiovascular Risks and Benefits of COVID-19 Vaccines: A Systematic Review

The rapid development and deployment of mRNA and non-mRNA COVID-19 vaccines have played a pivotal role in mitigating the global pandemic. Despite their success in reducing severe disease outcomes, emerging concerns about cardiovascular complications have raised questions regarding their safety. This systematic review critically evaluates the evidence on the cardiovascular effects of COVID-19 vaccines, assessing both their protective and adverse impacts, while considering the challenges posed by the limited availability of randomized controlled trial (RCT) data on these rare adverse events. In adherence to PRISMA 2020 guidelines, we conducted a systematic review using the Scopus database, incorporating articles published from January 2020 to July 2024. Our search included terms related to COVID-19 vaccines and cardiovascular conditions. We selected relevant studies from case-control studies, cohort studies, and clinical trials, while excluding descriptive analyses, cross-sectional studies, and conference reports. Case reports were also included due to the limited availability of extensive RCT data on the rare cardiovascular adverse events associated with COVID-19 vaccines. Of the 6037 articles initially screened, 410 were assessed in detail and 175 studies were ultimately included. The review identified a variety of cardiovascular adverse effects associated with COVID-19 vaccines. mRNA vaccines were primarily linked to myocarditis and pericarditis, particularly in younger males, with lower cardiac risks compared to COVID-19 infection. Adenoviral vector vaccines were associated with thrombosis and thrombocytopenia. Inactivated vaccines had fewer severe cardiovascular reports but still presented risks. Takotsubo cardiomyopathy was most commonly observed following mRNA vaccination. Case reports provided valuable additional insights into these rare events, highlighting clinical presentations and potential risk factors not fully captured by larger epidemiological studies. This review reveals a nuanced cardiovascular risk profile for COVID-19 vaccines, with mRNA vaccines linked to rare myocarditis and pericarditis in young males and a higher incidence of Takotsubo cardiomyopathy in females. Adenoviral vaccines show a notable association with thrombosis. Despite these risks, the benefits of vaccination in preventing severe COVID-19 outcomes outweigh the potential complications, underscoring the importance of continued surveillance, case report documentation, and personalized risk assessment. The inclusion of case reports was critical, as they provided valuable real-world data that complemented the findings from large-scale studies and RCTs.

Metalloparticle-Engineered Pickering Emulsion Displaying AAV-Vectored Vaccine for Enhancing Antigen Expression and Immunogenicity Against Pathogens

Recombinant adeno-associated viruses (rAAVs) have emerged as promising vaccine vectors due to their enduring efficacy with a single dose. However, insufficient cellular immune responses and the random and non-specific distribution of AAVs post-injection may hinder the development of AAV vaccines. Here, a novel Pickering emulsion platform stabilized by biomineralized manganese nanoparticles and aluminum hydroxide, which can rapidly and efficiently load AAVs, is reported. This platform confers AAVs with favorable in vivo distribution kinetics, diversifying AAV endocytic pathways with reduced dependency on the sialic acid receptor-mediated route, and ultimately enhancing AAV infection efficiency in antigen present cells (APCs). Concurrently, the Pickering emulsion substantially boosts endogenous 2'3'-cGAMP production, further activating the cGAS-STING pathway for stronger immune responses and improving protective efficacy in bacterial infection models. The STING pathway activation also increases AAV target gene expression, potently augmenting the cross-protective potential of AAV vaccines for COVID-19. These synergistic effects ensure that effective immune responses are induced even at one-fifth of the AAV vaccination dose, while the Pickering emulsion further reduces the accumulation of AAV in the liver, thereby improving their safety. The findings highlight the potential of Pickering emulsions as valuable enhancers for viral vectors, providing insights for their broader clinical applicability.

How do large-scale population studies inform vaccine evaluations in England?

Large-scale population studies are important to monitor and evaluate aspects of a vaccination programme including vaccine coverage, real-world effectiveness, and post-licensure vaccine safety. These types of epidemiological studies often come under the remit of public health agencies, such as the UK Health Security Agency (UKHSA) in England, which are required to undertake surveillance of vaccine-preventable diseases, including via seroepidemiological studies and data linkage studies using national-level electronic healthcare data. An individual-level national vaccine register with an accurate denominator can be the key to gaining insights into vaccine coverage, effectiveness, and safety. During the coronavirus disease 2019 pandemic, England's first vaccine register was developed. This enabled timely estimates of real-world vaccine effectiveness in the whole population of England, as well as enabling epidemiological investigations of rare potential risks from vaccines in specific populations. Population-based research studies, including prospective cohort studies, are complementary to surveillance and combined, enable more comprehensive assessments. As there was an unprecedented investment into research studies and infrastructure during the pandemic, the scale of these studies meant they were able to contribute to vaccine programme evaluations in a way that had not been possible for previous vaccine programmes. In this review, we summarise the different large-scale surveillance and research studies that have been used to evaluate and inform vaccine policy from the time of the first data linkage studies undertaken in England in the 1990s to the present-day post-COVID-19 pandemic.

Uptake and safety of Sotrovimab for prevention of severe COVID-19 in a cohort and self-controlled case series study

BACKGROUND

Sotrovimab is a neutralising monoclonal antibody (nMAB) currently available to treat extremely clinically vulnerable COVID-19 patients in England. Trials have shown it to have mild to moderate side effects, however, evidence regarding its safety in real-world settings remains insufficient.

METHODS

Descriptive and multivariable logistic regression analyses were conducted to evaluate uptake, and a self-controlled case series analysis performed to measure the risk of hospital admission (hospitalisation) associated with 49 pre-specified suspected adverse outcomes in the period 2-28 days post-Sotrovimab treatment among eligible patients treated between December 11, 2021 and May 24, 2022.

RESULTS

Here we show that among treated and untreated eligible individuals, the mean ages (54.6 years, SD: 16.1 vs 54.1, SD: 18.3) and sex distribution (women: 60.9% vs 58.1%; men: 38.9% vs 41.1%) are similar. There are marked variations in uptake between ethnic groups, which is higher amongst individuals categorised ethnically as Indian (15.0%; 95%CI 13.8, 16.3), Other Asian (13.7%; 95%CI 11.9, 15.8), white (13.4%; 95%CI 13.3, 13.6), and Bangladeshi (11.4%; 95%CI 8.8, 14.6); and lower amongst Black Caribbean individuals (6.4%; 95%CI 5.4, 7.5) and Black Africans (4.7%; 95%CI 4.1, 5.4). We find no increased risk of any of the suspected adverse outcomes in the period 2-28 days post-treatment.

CONCLUSIONS

We find no safety signals of concern for possible adverse outcomes in the period 2-28 days post treatment with Sotrovimab. However, there is evidence of unequal uptake of Sotrovimab treatment across ethnic groups.

Distinct response patterns of endothelial markers to the BNT162b2 mRNA COVID-19 booster vaccine are associated with the spike-specific IgG antibody production

Introduction

Despite the efficacy and safety of SARS-CoV-2 vaccines, inflammatory and/or thrombotic episodes have been reported. Since the impact of COVID-19 vaccines on the endothelium remains uncertain, our objective was to assess endothelial activation status before and 90 days after the third dose of the BNT162b2 mRNA COVID-19 vaccine.

Methods

A prospective longitudinal study was conducted at University General Hospital of Albacete, involving 38 healthy health-care workers. Serum levels of endothelial markers (endocan and sVCAM-1) and spike S1-specific IgG antibodies were determined before and at 7, 15, 24 and 90days following vaccination. To analyze each participant´s individual response, we calculated relative increases/decreases (delta values) in endothelial markers and antibodies concentrations compared to their pre-vaccination levels.

Results

We identified two significantly distinct profiles of endothelial markers response, characterized by either increased or decreased serum levels of endocan and sVCAM. Incremental and decremental response groups did not differ in terms of age, sex, cardiovascular risk factors, previous SARS-CoV-2 infection and influenza vaccine co-administration. However, these responses were significantly associated with the relative spike-specific antibody production. Specifically, the greatest relative increase in antibodies was found in the decremental responders. Additionally, the higher delta antibody production was observed in non-previously infected individuals.

Conclusion

Administration of the BNT162b2 booster vaccine triggered a non-homogenous response of endothelial function markers among the study participants. Our findings improve the understanding of individual responses to the mRNA COVID-19 booster vaccine, which could be useful in assessing the need for booster doses, particularly in population at risk of vascular complications.

Impact of COVID-19 disease and COVID-19 vaccinations on hospital admissions for neurological diseases in the Lombardia over-12 population. Data from a self-controlled case series analysis

INTRODUCTION

The influence of COVID19 vaccination on the risk of different neurological diseases has been subject of intense investigation. No large scale results have been published so far in the population of around 10 million people of Lombardia in Italy.

METHODS

Linkable administrative health databases from the Lombardia region were used. By using the adapted self controlled case series (SCCS) method for event dependent exposures, we estimated the relative incidence of different neurological diseases following pre-specified windows at risk after vaccination and after COVID-19 infection in the over-12 population of Lombardia. Follow-up time before vaccination (Pre-Vax period) was compared with follow-up time 0-28 days (high-risk period) from the day of vaccination as well as for COVID infection. The SCCS model was fitted using a conditional Poisson regression model to estimate the relative incidences (RI) and their 95% Confidence Intervals (CI).

RESULTS

The 28-day post-vaccination period was associated with a significant increase in the occurrence of ischemic stroke, cerebral haemorrhage, TIAs and myelitis (IRR 1.44, 1.50, 1.67 and 2.65 respectively). When the risk conferred by COVID19 infection was assessed in the same cohort, significant IRR were greater in the occurrence of ischemic stroke, cerebral haemorrhage, and TIAs (IRR 5.6, 3.62, 6.83) and includes also Multiple Sclerosis, neuromyelitis, and polymyositis (5.25, 8.81, 5.67).

CONCLUSIONS

Our data suggest that the increased risk of non-inflammatory CNS disorders following COVID-19 vaccination is lower than the risk conferred by COVID-19 infection, and that COVID-19 infection increases the risk of some inflammatory and non inflammatory neurological disorders.

Patient and Public Involvement in Pharmacoepidemiological Research: An Environmental Scan of an Emerging Area

BACKGROUND

Patient and public involvement (PPI) in research is required to improve the relevance, feasibility, and interpretability. However, research on PPIs in pharmacoepidemiology (PE) is still limited. This study aimed to provide an overview of PPI implementation in pharmacoepidemiology through an environmental scan.

METHODS

The environmental scan combined systematic reviews and expert interviews. A systematic review was conducted in MEDLINE, EMBASE, and the Cochrane Library from January 1, 2010, to June 30, 2023, to identify PE studies in which PPIs were mentioned. An additional review covered British Medical Journal's (BMJ) original articles from January 1, 2019, to June 30, 2023, via a similar method. In parallel, a cross-sectional study was conducted with a standardized questionnaire for French PE research teams, involving interviews via videoconference.

RESULTS

We identified 3615 references for screening, among which 232 were selected for full-text screening. However, no studies have reported the use of PPIs in PE studies. The additional BMJ review identified 1058 references, 74 of which met the full-text selection criteria, and eight were included. Of 13 French PE research teams surveyed, three had prior PPI experience, and 12 affirmed the relevance of PPI in PE. The respondents identified barriers such as PE's complexity (n = 9). They suggested training for patients (n = 9) and collaboration with specialist teams (n = 5) to facilitate PPI.

CONCLUSION

Our environmental scan highlighted the emergence and relevance of PPIs in PE studies, even though they are still uncommon. Tools are needed to acculture and assist PE researchers in engaging in PPIs.

Assessing acute kidney injury risk after COVID vaccination and infection in a large cohort study

Acute kidney injury (AKI) has been noticed after both COVID-19 vaccination and infection, affecting risk-benefit evaluations and vaccine hesitancy. We conducted a large-scale N3C cohort study to compare AKI incidence following COVID-19 vaccination and infection. Participants from December 2020 to August 2023 were divided into two groups based on their initially observed COVID-19 antigen exposure: COVID-19 vaccination group (n = 2,953,219) and COVID-19 infection group (n = 3,616,802). AKI was defined by diagnostic codes and serum creatinine changes within a 30 day follow-up window after exposure. The absolute risk of AKI was 0.66% in the vaccination group versus 4.88% in the infection group. After adjusting for various confounders, COVID-19 infection was associated with a significantly higher risk of AKI than COVID-19 vaccination (aHR = 10.31, P < 0.001). Our study reveals that COVID-19 vaccination is associated with a significant lower AKI risk compared to COVID-19 infection.

COVID-19 vaccinations pre- and antepartum: a consideration of the evidence and discussion of issues

PURPOSE

The COVID-19 vaccine should be universally offered to pregnant women and women planning pregnancies. This is on the basis that COVID-19 infection can complicate the pregnancy and have adverse health implications in pregnancy, as compared to non-pregnant women, which the vaccine helps to mitigate. This is the recommendation of many governing bodies in medical care. However, certain issues require consideration, which are not discussed in the current guidelines. These include the induction of fever by the vaccines and the role fever can play in teratogenicity, the induction of hyper-coagulable and thrombocytopenic states by the vaccines and other known contraindications to the vaccines. In this article, we develop strategies to minimize risks in these situations. We also discuss the theoretical advantage of calling for a booster COVID-19 vaccinate in all pregnant women in the late second or early third trimester, even if previously immunized, and encourage further research, to investigate the possible benefits of this proposed intervention. This article acts as an educational supplement to help clinicians manage pregnant women and addresses many issues, not discussed in most COVID-19 vaccine recommendations by international societies related to pregnant women.

METHODS

This article is a literature review of the current, limited data. The information extrapolated allowed for suggestions regarding COVID-19 vaccination during pregnancy. RESULTS AND CONCLUSIONS: The study discusses hypothetical issues, to minimize any risks associated with COVID-19, and serves as a compilation of data to further the current literature, in proving that COVID-19 vaccines have minimal risks in pregnancy.

Risk benefit analysis to evaluate risk of thromboembolic events after mRNA COVID-19 vaccination and COVID-19

We compared the risks and benefits of COVID-19 vaccines using a causal pathway analysis to weigh up possible risk factors of thromboembolic events post-vaccination. The self-controlled case series (SCCS) method examined the association between thromboembolic events and vaccination while a case-control study assessed the association between thromboembolic events and COVID-19, addressing under-reported infection data issues. The net vaccine effect was estimated using results from SCCS and case-control studies. We used electronic health record data from Corewell Health (16,640 subjects in SCCS and 106,143 in case-control). We found increased risks of thromboembolic events post-vaccination (incidence rate ratio: 1.19, 95% CI: [1.08, 1.31] after the first dose; 1.22, 95% CI: [1.11, 1.34] after the second dose). Vaccination attenuated infection-associated thromboembolic risks (odds ratio: 4.65, 95% CI: [4.18, 5.17] in unvaccinated vs 2.77, 95% CI: [2.40, 3.24] in vaccinated). After accounting for vaccine efficacy and protection against infection-associated thromboembolic events, vaccination decreases thromboembolic event risk, especially during high infection rate periods.

Identifying and reducing risks of neurological complications associated with vaccination

Vaccines protect against many infectious diseases, including some that can directly or indirectly cause nervous system damage. Serious neurological consequences of immunization are typically extremely rare, although they have the potential to jeopardize vaccination programmes, as demonstrated most recently during the COVID-19 pandemic. Neurologists have an important role in identifying safety signals at population and individual patient levels, as well as providing advice on the benefit-risk profile of vaccination in cohorts of patients with diverse neurological conditions. This article reviews the links between vaccination and neurological disease and considers how emerging signals can be evaluated and their mechanistic basis identified. We review examples of neurotropic infections with live attenuated vaccines, as well as neuroimmunological and neurovascular sequelae of other types of vaccines. We emphasize that such risks are typically dwarfed by neurological complications associated with natural infection and discuss how the risks can be further mitigated. The COVID-19 pandemic has highlighted the need to rapidly identify and minimize neurological risks of vaccination, and we review the structures that need to be developed to protect public health against these risks in the future.

Acute Respiratory Distress Syndrome After Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) Vaccination: Findings From an Autopsy

A male patient in his 80s was brought to our emergency room with a one-day history of general malaise and cough. He had received a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccination seven days earlier. He initially presented with respiratory failure, and an alveolar hemorrhage was suspected. The patient was intubated and admitted to the intensive care unit. We suspected that the alveolar hemorrhage was caused by acute respiratory distress syndrome (ARDS). Treatment including high-dose corticosteroid therapy and venovenous extracorporeal membrane oxygenation (ECMO) was initiated, however, the patient did not respond to treatment and died 35 days after admission. Pathological autopsy revealed diffuse alveolar damage (DAD) and idiopathic diffuse alveolar hemorrhage (DAH) consistent with ARDS. ARDS should be considered as a differential diagnosis when a patient develops respiratory symptoms after receiving the SARS-CoV-2 vaccine.

Thromboembolism after coronavirus disease 2019 vaccination in atrial fibrillation/flutter: a self-controlled case series study

BACKGROUND AND AIMS

Concerns about the safety of coronavirus disease 2019 (COVID-19) vaccines in patients with atrial fibrillation/flutter (AF/AFL) have arisen due to reports of thrombo-embolic events following COVID-19 vaccination in the general population. This study aimed to evaluate the risk of thrombo-embolic events after COVID-19 vaccination in patients with AF/AFL.

METHODS

This was a modified self-controlled case-series study using a comprehensive nationwide-linked database provided by the National Health Insurance Service in South Korea to calculate incidence rate ratios (IRRs) of thrombo-embolic events. The study population included individuals aged ≥12 years who were either vaccinated (e.g. one or two doses) or unvaccinated during the period from February to December 2021. The primary outcome was a composite of thrombo-embolic events, including ischaemic stroke, transient ischaemic attack, and systemic thromboembolism. The risk period was defined as 0-21 days following COVID-19 vaccination.

RESULTS

The final analysis included 124 127 individuals with AF/AFL. The IRR of thrombo-embolic events within 21 days after COVID-19 vaccination, compared with that during the unexposed control period, was 0.93 [95% confidence interval (CI) 0.77-1.12]. No significant risk variations were noted by sex, age, or vaccine type. However, patients without anticoagulant therapy had an IRR of 1.88 (95% CI 1.39-2.54) following vaccination.

CONCLUSIONS

In patients with AF/AFL, COVID-19 vaccination was generally not associated with an increased risk of thrombo-embolic events. However, careful individual risk assessment is required when advising vaccination for those not on oral anticoagulant, as these patients exhibited an increased risk of thrombo-embolic events post-vaccination.

Cohort study of cardiovascular safety of different COVID-19 vaccination doses among 46 million adults in England

The first dose of COVID-19 vaccines led to an overall reduction in cardiovascular events, and in rare cases, cardiovascular complications. There is less information about the effect of second and booster doses on cardiovascular diseases. Using longitudinal health records from 45.7 million adults in England between December 2020 and January 2022, our study compared the incidence of thrombotic and cardiovascular complications up to 26 weeks after first, second and booster doses of brands and combinations of COVID-19 vaccines used during the UK vaccination program with the incidence before or without the corresponding vaccination. The incidence of common arterial thrombotic events (mainly acute myocardial infarction and ischaemic stroke) was generally lower after each vaccine dose, brand and combination. Similarly, the incidence of common venous thrombotic events, (mainly pulmonary embolism and lower limb deep venous thrombosis) was lower after vaccination. There was a higher incidence of previously reported rare harms after vaccination: vaccine-induced thrombotic thrombocytopenia after first ChAdOx1 vaccination, and myocarditis and pericarditis after first, second and transiently after booster mRNA vaccination (BNT-162b2 and mRNA-1273). These findings support the wide uptake of future COVID-19 vaccination programs.

Inflammatory risk contributes to post-COVID endothelial dysfunction through anti-ACKR1 autoantibody

Subclinical vascular impairment can be exacerbated in individuals who experience sustained inflammation after COVID-19 infection. Our study explores the prevalence and impact of autoantibodies on vascular dysfunction in healthy COVID-19 survivors, an area that remains inadequately investigated. Focusing on autoantibodies against the atypical chemokine receptor 1 (ACKR1), COVID-19 survivors demonstrated significantly elevated anti-ACKR1 autoantibodies, correlating with systemic cytokines, circulating damaged endothelial cells, and endothelial dysfunction. An independent cohort linked these autoantibodies to increased vascular disease outcomes during a median 6.7-yr follow-up. We analyzed a single-cell transcriptome atlas of endothelial cells from diverse mouse tissues, identifying enriched Ackr1 expressions in venous regions of the brain and soleus muscle vasculatures, which holds intriguing implications for tissue-specific venous thromboembolism manifestations reported in COVID-19. Functionally, purified immunoglobulin G (IgG) extracted from patient plasma did not trigger cell apoptosis or increase barrier permeability in human vein endothelial cells. Instead, plasma IgG enhanced antibody-dependent cellular cytotoxicity mediated by patient PBMCs, a phenomenon alleviated by blocking peptide or liposome ACKR1 recombinant protein. The blocking peptide uncovered that purified IgG from COVID-19 survivors possessed potential epitopes in the N-terminal extracellular domain of ACKR1, which effectively averted antibody-dependent cellular cytotoxicity. Our findings offer insights into therapeutic development to mitigate autoantibody reactivity in blood vessels in chronic inflammation.

Association between COVID-19 Vaccination (ChAdOx1-S) and Thromboembolic, Thrombocytopenic, Hemorrhagic Events: A Systematic Review and Meta-analysis of Analytical Epidemiological Studies

We conducted a systematic review of analytical epidemiological studies to assess the association between ChAdOx1-S vaccination and thromboembolic, thrombocytopenic, and hemorrhagic events. We searched Medline, Embase, Google Scholar, WHO-COVID-19 database, and medRxiv for studies evaluating the association between ChAdOx1-S and vascular events. Primary outcomes of interest were cerebral venous sinus thrombosis, peripheral venous thrombosis (PVT), and thrombocytopenia. Two independent reviewers screened for eligible studies, extracted data, and assessed the risk of bias. The DerSimonian-Laird random effects model was used to pool the incidence rate ratios (IRRs) separately for the first and second doses. Heterogeneity was assessed using I2 statistics. Twenty studies were included, of which 11 were self-controlled case series, and nine were cohort studies (254 million participants). Pooling of 17 studies showed a higher risk of cerebrovascular thrombosis (IRR = 3.5, 95% CI = 2.2-5.4, I2 = 79%), PVT (IRR = 2.0, 95% CI = 1.1-3.5, I2 = 95%) and thrombocytopenia (IRR = 1.6, 95% CI = 1.4-1.9, I2 = 93%) among those who received ChAdOx1-S vaccination as compared to controls. No increased risk was seen after the second dose or for secondary outcomes. There is moderate-to-high certainty of the evidence for the increased risk of cerebral venous sinus thrombosis, PVT, and thrombocytopenia following the first dose of the ChAdOx1-S vaccine. Systematic Review Registration: PROSPERO CRD42022372768.

COVID-19 vaccination and major cardiovascular and haematological adverse events in Abu Dhabi: retrospective cohort study

The widespread administration of COVID-19 vaccines has prompted a need to understand their safety profile. This investigation focuses on the safety of inactivated and mRNA-based COVID-19 vaccines, particularly concerning potential cardiovascular and haematological adverse events. A retrospective cohort study was conducted for 1.3 million individuals residing in Abu Dhabi, United Arab Emirates, who received 1.8 million doses of the inactivated BBIBP CorV (by SinoPharm) and mRNA-based BNT162b2 (Pfizer-BioNTech) vaccines between June 1, 2021, and June 30, 2022. The study's primary outcome was to assess the occurrence of selected cardiovascular and haematological events leading to hospitalization or emergency room visits within 21 days post-vaccination. Results showed no significant increase in the incidence rates of these events compared to the subsequent 22 to 42 days following vaccination. Analysis revealed no elevated risk for adverse outcomes following first (IRR 1·03; 95% CI 0·82-1·31), second (IRR 0·92; 95% CI 0·72-1·16) and third (IRR 0·82; 95% CI 0·66-1·00) doses of either vaccine. This study found no substantial link between receiving either mRNA and inactivated COVID-19 vaccines and a higher likelihood of cardiovascular or haematological events within 21 days after vaccination.

Venous thromboembolism in Black COVID-19 patients in a minority context compared to White, Asian and other racialized patients: A systematic review and meta-analysis

IMPORTANCE

COVID-19 has disproportionately affected racialized populations, with particular impact among individuals of Black individuals. However, it is unclear whether disparities in venous thromboembolic (VTE) complications exist between Black individuals and those belonging to other racial groups with confirmed SARS-CoV2 infections.

OBJECTIVE

To summarize the prevalence and moderators associated with VTE among Black COVID-19 patients in minoritized settings, and to compare this to White and Asian COVID-19 patients according to sex, age, and comorbid health conditions (heart failure, cancer, obesity, hypertension).

DESIGN SETTING, AND PARTICIPANTS

A systematic search of MEDLINE, Embase, CINAHL and CENTRAL for articles or reports published from inception to February 15, 2023.

STUDY SELECTION

Reports on VTE among Black individuals infected with SARS-CoV2, in countries where Black people are considered a minority population group.

DATA EXTRACTION AND SYNTHESIS

Study characteristics and results of eligible studies were independently extracted by 2 pairs of reviewers. VTE prevalence was extracted, and risk of bias was assessed. Prevalence estimates of VTE prevalence among Black individuals with COVID19 in each study were pooled. Where studies provided race-stratified VTE prevalence among COVID19 patients, odds ratios were generated using a random-effects model.

MAIN OUTCOMES AND MEASURES

Prevalence of VTE, comprising of deep vein thrombosis and pulmonary embolism.

RESULTS

Ten studies with 66,185 Black individuals reporting the prevalence of COVID-19 associated VTE were included. Weighted median age of included studies was 47.60. Pooled prevalence of COVID-19 associated VTE was 7.2 % (95 % CI, 3.8 % - 11.5 %) among Black individuals. Among individuals with SARS-CoV2 infections, Black population had higher risks of VTE compared to their White (OR = 1.79, [95 % CI 1.28-2.53], p < .001) or Asian (OR = 2.01, [95 % CI, 1.14-3.60], p = .017) counterparts, or patients with other racial identities (OR = 2.01, [95 % CI, 1.39, 2.92]; p < .001).

CONCLUSIONS AND RELEVANCE

Black individuals with COVID-19 had substantially higher risk of VTE compared to White or Asian individuals. Given racial disparities in thrombotic disease burden related to COVID-19, medical education, research, and health policy interventions are direly needed to ensure adequate disease awareness among Black individuals, to facilitate appropriate diagnosis and treatment among Black patients with suspected and confirmed VTE, and to advocate for culturally safe VTE prevention strategies, including pre-existing inequalities to the COVID-19 pandemic that persist after the crisis.

Neurovascular Adverse Effects of Sars-Cov-2 Vaccination

The global deployment of SARS-CoV-2 vaccines has been pivotal in curbing the COVID-19 pandemic, reducing morbidity and mortality associated with the virus. While most of these vaccines have demonstrated high efficacy and overall safety, emerging reports have highlighted potential neurovascular adverse effects, albeit uncommon, associated with these vaccinations. This review aims to assess and summarize the current knowledge on the neurovascular complications arising post-SARS-CoV-2 vaccination. We conducted an extensive literature review, focusing on clinical studies and case reports to identify reported neurovascular events, such as ischemic stroke, cerebral sinus venous thrombosis, intracerebral hemorrhage, pituitary apoplexy and primary CNS angiitis Despite the relative rarity of these events, their impact on affected individuals underscores the importance of ongoing surveillance, early detection, and management strategies. We aim to provide healthcare professionals with the latest evidence on neurovascular adverse effects, facilitating informed decision-making in the context of SARS-CoV-2 vaccination programs. Furthermore, we highlight areas requiring further research to understand the pathophysiology of these adverse events better and to develop targeted prevention and treatment strategies.

Safety outcomes following COVID-19 vaccination and infection in 5.1 million children in England

The risk-benefit profile of COVID-19 vaccination in children remains uncertain. A self-controlled case-series study was conducted using linked data of 5.1 million children in England to compare risks of hospitalisation from vaccine safety outcomes after COVID-19 vaccination and infection. In 5-11-year-olds, we found no increased risks of adverse events 1-42 days following vaccination with BNT162b2, mRNA-1273 or ChAdOX1. In 12-17-year-olds, we estimated 3 (95%CI 0-5) and 5 (95%CI 3-6) additional cases of myocarditis per million following a first and second dose with BNT162b2, respectively. An additional 12 (95%CI 0-23) hospitalisations with epilepsy and 4 (95%CI 0-6) with demyelinating disease (in females only, mainly optic neuritis) were estimated per million following a second dose with BNT162b2. SARS-CoV-2 infection was associated with increased risks of hospitalisation from seven outcomes including multisystem inflammatory syndrome and myocarditis, but these risks were largely absent in those vaccinated prior to infection. We report a favourable safety profile of COVID-19 vaccination in under-18s.

Factors associated with SARS-CoV-2 vaccine hesitancy after stroke: a cross-sectional study

BACKGROUND

The vaccination status of post-stroke patients, who are at high risk of severe outcomes from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is a significant concern, yet it remains unclear. We aimed to explore the vaccination status, factors associated with vaccine hesitancy, and adverse effects after vaccination among post-stroke patients.

METHODS

This multi-center observational study enrolled hospitalized post-stroke patients from six Chinese hospitals (Oct 1, 2020 - Mar 31, 2021), examining vaccine uptake and self-reported reasons for vaccine hesitancy, utilizing logistic regression to investigate risk factors for vaccine hesitancy, and recording any adverse reactions post-vaccination.

RESULTS

Of the total 710 post-stroke patients included in the study, 430 (60.6%) had completed the recommended full-3 dose SARS-CoV-2 vaccination, with 176 (24.8%) remaining unvaccinated. The most common reasons for vaccine hesitancy were concerns about vaccine side effects (41.5%) and impaired mobility (33.9%). Logistic regression identified advanced age (aOR = 1.97, 95%CI: 1.36-2.85, P = 0.001), lower Barthel Index score (aOR = 0.88, 95%CI: 0.82-0.93, P = 0.018), higher Modified Rankin Scale score (aOR = 1.85, 95%CI: 1.32-2.56, P = 0.004), and poorer usual activity level of EuroQol 5-Dimension (aOR = 2.82, 95%CI: 1.51-5.28, P = 0.001) as independent risk factors for vaccine hesitancy. Approximately 14.8% reported minor adverse reactions, mainly pain at the injection site.

CONCLUSION

We found that post-stroke patients have insufficient SARS-CoV-2 vaccination rates, with key risk factors for vaccine hesitancy including concerns about side effects, advanced age, and functional impairments. No severe adverse reactions were observed among the vaccinated population.

Estimation and reduction of bias in self-controlled case series with non-rare event dependent outcomes and heterogeneous populations

The self-controlled case series (SCCS) is a commonly adopted study design in the assessment of vaccine and drug safety. Recurrent event data collected from SCCS studies are typically analyzed using the conditional Poisson model which assumes event times are independent within-cases. This assumption is violated in the presence of event dependence, where the occurrence of an event influences the probability and timing of subsequent events. When event dependence is suspected in an SCCS study, the standard recommendation is to include only the first event from each case in the analysis. However, first event analysis can still yield biased estimates of the exposure relative incidence if the outcome event is not rare. We first demonstrate that the bias in first event analysis can be even higher than previously assumed when subpopulations with different baseline incidence rates are present and describe an improved method for estimating this bias. Subsequently, we propose a novel partitioned analysis method and demonstrate how it can reduce this bias. We provide a recommendation to guide the number of partitions to use with the partitioned analysis, illustrate this recommendation with an example SCCS study of the association between beta-blockers and acute myocardial infarction, and compare the partitioned analysis against other SCCS analysis methods by simulation.

The role of COVID-19 vaccines in preventing post-COVID-19 thromboembolic and cardiovascular complications

OBJECTIVE

To study the association between COVID-19 vaccination and the risk of post-COVID-19 cardiac and thromboembolic complications.

METHODS

We conducted a staggered cohort study based on national vaccination campaigns using electronic health records from the UK, Spain and Estonia. Vaccine rollout was grouped into four stages with predefined enrolment periods. Each stage included all individuals eligible for vaccination, with no previous SARS-CoV-2 infection or COVID-19 vaccine at the start date. Vaccination status was used as a time-varying exposure. Outcomes included heart failure (HF), venous thromboembolism (VTE) and arterial thrombosis/thromboembolism (ATE) recorded in four time windows after SARS-CoV-2 infection: 0-30, 31-90, 91-180 and 181-365 days. Propensity score overlap weighting and empirical calibration were used to minimise observed and unobserved confounding, respectively.Fine-Gray models estimated subdistribution hazard ratios (sHR). Random effect meta-analyses were conducted across staggered cohorts and databases.

RESULTS

The study included 10.17 million vaccinated and 10.39 million unvaccinated people. Vaccination was associated with reduced risks of acute (30-day) and post-acute COVID-19 VTE, ATE and HF: for example, meta-analytic sHR of 0.22 (95% CI 0.17 to 0.29), 0.53 (0.44 to 0.63) and 0.45 (0.38 to 0.53), respectively, for 0-30 days after SARS-CoV-2 infection, while in the 91-180 days sHR were 0.53 (0.40 to 0.70), 0.72 (0.58 to 0.88) and 0.61 (0.51 to 0.73), respectively.

CONCLUSIONS

COVID-19 vaccination reduced the risk of post-COVID-19 cardiac and thromboembolic outcomes. These effects were more pronounced for acute COVID-19 outcomes, consistent with known reductions in disease severity following breakthrough versus unvaccinated SARS-CoV-2 infection.

Effectiveness and safety of COVID-19 vaccination in people with blood cancer

BACKGROUND

People with blood cancer have increased risk of severe COVID-19 outcomes and poor response to vaccination. We assessed the safety and effectiveness of COVID-19 vaccines in this vulnerable group compared to the general population.

METHODS

Individuals aged ≥12 years as of 1st December 2020 in the QResearch primary care database were included. We assessed adjusted COVID-19 vaccine effectiveness (aVE) against COVID-19-related hospitalisation and death in people with blood cancer using a nested matched case-control study. Using the self-controlled case series methodology, we compared the risk of 56 pre-specified adverse events within 1-28 days of a first, second or third COVID-19 vaccine dose in people with and without blood cancer.

FINDINGS

The cohort comprised 12,274,948 individuals, of whom 81,793 had blood cancer. COVID-19 vaccines were protective against COVID-19-related hospitalisation and death in people with blood cancer, although they were less effective, particularly against COVID-19-related hospitalisation, compared to the general population. In the blood cancer population, aVE against COVID-19-related hospitalisation was 64% (95% confidence interval [CI] 48%-75%) 14-41 days after a third dose, compared to 80% (95% CI 78%-81%) in the general population. Against COVID-19-related mortality, aVE was >80% in people with blood cancer 14-41 days after a second or third dose. We found no significant difference in risk of adverse events 1-28 days after any vaccine dose between people with and without blood cancer.

INTERPRETATION

Our study provides robust evidence which supports the use of COVID-19 vaccinations for people with blood cancer.

Adverse events after first and second doses of COVID-19 vaccination in England: a national vaccine surveillance platform self-controlled case series study

OBJECTIVES

To estimate the incidence of adverse events of interest (AEIs) after receiving their first and second doses of coronavirus disease 2019 (COVID-19) vaccinations, and to report the safety profile differences between the different COVID-19 vaccines.

DESIGN

We used a self-controlled case series design to estimate the relative incidence (RI) of AEIs reported to the Oxford-Royal College of General Practitioners national sentinel network. We compared the AEIs that occurred seven days before and after receiving the COVID-19 vaccinations to background levels between 1 October 2020 and 12 September 2021.

SETTING

England, UK.

PARTICIPANTS

Individuals experiencing AEIs after receiving first and second doses of COVID-19 vaccines.

MAIN OUTCOME MEASURES

AEIs determined based on events reported in clinical trials and in primary care during post-license surveillance.

RESULTS

A total of 7,952,861 individuals were vaccinated with COVID-19 vaccines within the study period. Among them, 781,200 individuals (9.82%) presented to general practice with 1,482,273 AEIs. Within the first seven days post-vaccination, 4.85% of all the AEIs were reported. There was a 3-7% decrease in the overall RI of AEIs in the seven days after receiving both doses of Pfizer-BioNTech BNT162b2 (RI = 0.93; 95% CI: 0.91-0.94) and 0.96; 95% CI: 0.94-0.98), respectively) and Oxford-AstraZeneca ChAdOx1 (RI = 0.97; 95% CI: 0.95-0.98) for both doses), but a 20% increase after receiving the first dose of Moderna mRNA-1273 (RI = 1.20; 95% CI: 1.00-1.44)).

CONCLUSIONS

COVID-19 vaccines are associated with a small decrease in the incidence of medically attended AEIs. Sentinel networks could routinely report common AEI rates, which could contribute to reporting vaccine safety.

Incidence rates of thrombosis with thrombocytopenia syndrome (TTS) among adults in United States commercial and Medicare claims databases, 2017-2020

BACKGROUND

Increased risk of thrombosis with thrombocytopenia syndrome (TTS) following adenovirus vector-based COVID-19 vaccinations has been identified in passive surveillance systems. TTS incidence rates (IRs) in the United States (U.S.) are needed to contextualize reports following COVID-19 vaccination.

METHODS

We estimated annual and monthly IRs of overall TTS, common site TTS, and unusual site TTS for adults aged 18-64 years in Carelon Research and MarketScan commercial claims (2017-Oct 2020), CVS Health and Optum commercial claims (2019-Oct 2020), and adults aged ≥ 65 years using CMS Medicare claims (2019-Oct 2020); IRs were stratified by age, sex, and race/ethnicity (CMS Medicare).

RESULTS

Across data sources, annual IRs for overall TTS were similar between Jan-Dec 2019 and Jan-Oct 2020. Rates were higher in Medicare (IRs: 370.72 and 365.63 per 100,000 person-years for 2019 and 2020, respectively) than commercial data sources (MarketScan IRs: 24.21 and 24.06 per 100,000 person-years; Optum IRs: 32.60 and 31.29 per 100,000 person-years; Carelon Research IRs: 24.46 and 26.16 per 100,000 person-years; CVS Health IRs: 30.31 and 30.25 per 100,000 person-years). Across years and databases, common site TTS IRs increased with age and were higher among males. Among adults aged ≥ 65 years, the common site TTS IR was highest among non-Hispanic black adults. Annual unusual site TTS IRs ranged between 2.02 and 3.04 (commercial) and 12.49 (Medicare) per 100,000 person-years for Jan-Dec 2019; IRs ranged between 1.53 and 2.67 (commercial) and 11.57 (Medicare) per 100,000 person-years for Jan-Oct 2020. Unusual site TTS IRs were higher in males and increased with age in commercial data sources; among adults aged ≥ 65 years, IRs decreased with age and were highest among non-Hispanic American Indian/Alaska native adults.

CONCLUSION

TTS IRs were generally similar across years, higher for males, and increased with age. These rates may contribute to surveillance of post-vaccination TTS.

Autoimmune disorders reported following COVID-19 vaccination: A disproportionality analysis using the WHO database

PURPOSE

Owing to adverse event following immunization (AEFI) related to autoimmune disorders and coronavirus disease 2019 (COVID-19) vaccines sharing common biological mechanisms, identifying the risk of AEFIs associated with COVID-19 vaccines remains a critical unmet need. We aimed to assess the potential safety signals for 16 AEFIs and explore co-reported adverse events (AEs) and drugs using the global database of the World Health Organization, VigiBase.

METHODS

We assessed the occurrence of 16 AEFIs following COVID-19 vaccination through the Standardized MedDRA Queries group "Immune-mediated/Autoimmune Disorders" from MedDRA and performed a disproportionality analysis using reporting odds ratio (ROR) and information component (IC) with 95% confidence intervals (CIs).

RESULTS

We identified 25,219 events associated with COVID-19 vaccines in VigiBase. Although rare, we detected four potential safety signals related to autoimmune disorders following COVID-19 vaccination, including ankylosing spondylitis or psoriatic arthritis (ROR 1.86; 95% CI 1.53-2.27), inflammatory bowel disease (ROR 1.77; 95% CI 1.60-1.96), polymyalgia rheumatica (ROR 1.42; 95% CI 1.30-1.55), and thyroiditis (ROR 1.40; 95% CI 1.30-1.50), with positive IC025 values. The top co-reported AEs were musculoskeletal disorders, and immunosuppressants were the most representative co-reported drugs.

CONCLUSION

In addressing the imperative to comprehend AEFI related to autoimmune disorders following COVID-19 vaccination, our study identified four potential safety signals. Thus, our research underscores the importance of proactive safety monitoring for the identification of the four AEFIs following COVID-19 vaccination, considering the associated advantages.

Management of COVID-19 in Ophthalmology

From its outbreak in early 2020, the new SARS-CoV-2 infection has deeply affected the entire eye care system for several reasons. Since the beginning of the COVID-19 pandemic, ophthalmologists were among the "high-risk category" for contracting the SARS-CoV-2 infection based on the notion that the eye was suspected to be a site of inoculation, infection, and transmission. Clinical ophthalmologists have been required to learn and promptly recognize the ocular manifestations associated with the COVID-19 disease, with its treatments and vaccinations. Restriction measures, lockdown periods, guidelines to prevent SARS-CoV-2 infection transmission, and the use of telemedicine and artificial intelligence modalities have induced profound modifications. These changes, which are most likely to be irreversible, influence routine clinical practice, education, and research, thus giving rise to a "new ophthalmology in the COVID era". This book chapter aims to provide several notions regarding COVID-19 in ophthalmology, including the SARS-CoV-2 virus infection and transmission modalities; the ocular manifestation associated with the COVID-19 disease; the drugs and vaccines used for COVID-19; the precautions adopted in the ophthalmic practice to limit the spread of the virus; the consequences of the pandemic on the ophthalmic patients, clinicians, and the entire eye care system; and, the future of ophthalmology in the era of "COVID new normal".

Recovery From Central Retinal Artery Occlusion Accompanying Paracentral Acute Middle Maculopathy After COVID-19 Vaccination

Although ocular complications following COVID-19 vaccination have been reported, particularly retinal vascular occlusion and uveitis, their definitive causal relationships remain uncertain. This report presents a case of central retinal artery occlusion (CRAO) with paracentral acute middle maculopathy (PAMM) developed one day after receiving Pfizer COVID-19 vaccine, with a favorable outcome. The patient experienced sudden vision loss in her left eye, and her vision dropped to hand motion the day after vaccination. The initial examination suggested CRAO, but optical coherence tomography (OCT) revealed PAMM. We administered intravenous d-mannitol and acetazolamide and performed ocular massage. Two days later, her corrected visual acuity improved to 0.4, and further improvement to 1.2 occurred after 16 days. To the best of our knowledge, no reports have documented CRAO with PAMM following mRNA COVID-19 vaccination. The relationship between COVID-19 vaccination and retinal vascular occlusion remains unknown, highlighting the need for further research.

Posterior scleritis following COVID-19 vaccination or infection simulating uveal melanoma in 8 consecutive patients

OBJECTIVES

To determine clinical features and outcomes of posterior scleritis masquerading as uveal melanoma following vaccination against COVID-19 and/or COVID-19 infection.

SUBJECTS/METHODS

All patients with posterior scleritis referred to our service to rule out intraocular tumour between February 2021 and June 2022, who previously had COVID-19 vaccination and/or infection (n = 8). A retrospective detailed review of patient charts and imaging was carried out.

RESULTS

Previous COVID-19 vaccination was documented in 6 patients (75%) and previous COVID-19 infection and vaccination in 2 patients (25%). Demographic features included mean age of 59 years (median 68, range 5-86 years), white race (n = 7, 87%), and male sex (n = 5, 63%). Mean visual acuity at presentation was 0.24 LogMAR (median 0.18, range 0.0-0.70). The main presenting symptom was blurred vision with pain (n = 5, 63%). Features that suggested scleritis and not uveal melanoma included pain (n = 6, 75%), anterior scleritis (n = 3, 38%), disc oedema (n = 1, 13%), choroidal detachment (n = 3, 38%), choroidal folds (n = 3, 38%), diffusely thickened scleral wall on ultrasonography (n = 2, 25%), Tenon's oedema (n = 5, 63%), and scleral nodule with medium/high internal reflectivity on ultrasonography (n = 4, 50%). Follow-up information at mean of 2 months (range 0.25-7 months) revealed visual acuity at date last seen was mean 0.30 LogMAR (median 0.29, range 0.0-0.54). By 2 months, resolution of "tumour" was noted in 5/6 (83%) patients with follow-up.

CONCLUSIONS

Posterior scleritis following COVID-19 vaccination and/or infection can masquerade as choroidal melanoma. At 2 months duration, partial or complete resolution of features with minimal visual consequence was noted.

BAYESIAN LEARNING OF COVID-19 VACCINE SAFETY WHILE INCORPORATING ADVERSE EVENTS ONTOLOGY

While vaccines are crucial to end the COVID-19 pandemic, public confidence in vaccine safety has always been vulnerable. Many statistical methods have been applied to VAERS (Vaccine Adverse Event Reporting System) database to study the safety of COVID-19 vaccines. However, none of these methods considered the adverse event (AE) ontology. AEs are naturally related; for example, events of retching, dysphagia, and reflux are all related to an abnormal digestive system. Explicitly bringing AE relationships into the model can aid in the detection of true AE signals amid the noise while reducing false positives. We propose a Bayesian graph-assisted signal selection (BGrass) model to simultaneously estimate all AEs while incorporating the network of dependence between AEs. Under a fully Bayesian inference framework, we also propose a negative control approach to mitigate the reporting bias and an enrichment approach to detecting AE groups of concern. For posterior computation we construct an equivalent model representation and develop an efficient Gibbs sampler. We evaluate the performance of BGrass via extensive simulations. To study the safety of COVID-19 vaccines, we apply BGrass to analyze approximately one million VAERS reports (01/01/2016-12/24/2021) involving more than 800 AEs. In particular, we found that blood clots (including deep vein thrombosis, thrombosis, and pulmonary embolism) are more likely to be reported after COVID-19 vaccination, compared to influenza vaccines. They are also reported more often for Johnson & Johnson-Janssen vaccine, compared to mRNA-based COVID-19 vaccines. A user-friendly R package BGrass that implements the proposed methods to assess vaccine safety is included in the Supplementary Material and is publicly available at https://github.com/BangyaoZhao/BGrass.

Thrombocytopenia and venous thromboembolic events after BNT162b2, CoronaVac, ChAdOx1 vaccines and SARS-CoV-2 infection: a self-controlled case series study

This study assessed the association between COVID-19 vaccines, SARS-CoV-2 infection and the risk of thrombocytopenia and venous thromboembolism (VTE). This self-controlled case series study used hospital records between 1st February 2021 and 28th February 2022 linked to the national immunisation registry and COVID-19 surveillance data in Malaysia. Conditional Poisson regression was used to estimate incidence rate ratios (IRR) of events in the risk period (day 1-21 post-exposure) relative to control period with the corresponding 95% confidence interval (CI) adjusted for calendar period. We found no significant increased risk of thrombocytopenia in 1-21 days following BNT162b2, CoronaVac and ChAdOx1 vaccines while the risk was increased following SARS-CoV-2 infection (IRR 15.52, 95% CI 13.38-18.00). Similarly, vaccination with BNT162b2, CoronaVac, or ChAdOx1 was not associated with an increased risk of VTE during the 1-21 days risk period. SARS-CoV-2 infection was associated with increased risk of VTE (IRR 39.84, 95% CI 27.45-32.44). Our findings showed low event rates of thrombocytopenia and VTE following booster vaccination with comparable safety profiles between those who received homologous and heterologous booster combinations. Our findings showed the risk of thrombocytopenia and VTE was not increased after COVID-19 vaccination while the risks were substantially higher after SARS-CoV-2 infection.

Stroke Following Coronavirus Disease 2019 Vaccination: Evidence Based on Different Designs of Real-World Studies

BACKGROUND

We aimed to evaluate whether coronavirus disease 2019 (COVID-19) vaccination was associated with stroke.

METHODS

We conducted a systematic meta-analysis of studies using cohort, self-controlled case series (SCCS), and case-crossover study (CCOS) designs to evaluate incidence risk ratios (IRRs) and 95% confidence intervals (CIs) of ischemic stroke (IS), hemorrhagic stroke (HS), and cerebral venous sinus thrombosis (CVST) following COVID-19 vaccination. Risks of stroke were pooled among subpopulations categorized by vaccine type, dose, age, and sex. Sensitivity analysis was performed by different defined risk periods.

RESULTS

Fourteen studies involving 79 918 904 individuals were included. Cohort studies showed decreased risks of IS (IRR, 0.82 [95% CI, .75-.90]) and HS (IRR, 0.75 [95% CI, .67-.85]) postvaccination, but not CVST (IRR, 1.18 [95% CI, .70-1.98]). SCCS identified increased risks 1-21 days postvaccination (IRRIS, 1.05 [95% CI, 1.00-1.10]; IRRHS, 1.16 [95% CI, 1.06-1.26]) or 1-28 days postvaccination (IRRIS, 1.04 [95% CI, 1.00-1.08]; IRRHS, 1.37 [95% CI, 1.15-1.64]), similar to CVST (IRR, 1.58 [95% CI, 1.08-2.32]). CCOS reported an increased risk of CVST after ChAdOx1 vaccination (IRR, 2.9 [95% CI, 1.1-7.2]).

CONCLUSIONS

Although different study designs yielded inconsistent findings, considering the relatively low background incidence of stroke and benefits of vaccination, even a potentially increased risk of stroke postvaccination should not justify vaccine hesitancy.

BASILAR ARTERY REOCCLUSION WITHIN 24 HOURS AFTER MECHANICAL THROMBECTOMY SUCCESSFULLY TREATED WITH NEW INTERVENTION

Acute basilar artery occlusion (BAO) may cause ischemia in the region of brainstem, parts of the thalamus, occipital lobes, and cerebellum, resulting in severe disability or mortality rate above 70%. Recurrent BAO has been described in only a small number of cases. We present a case of repeated mechanical thrombectomy (MT) for the tip of basilar artery (BA) reocclusion within 24 hours. A previously healthy 37-year-old male presented with occipital headache, nausea, vomiting, right-sided hemiparesis, within 30 minutes from the onset and NIHSS 18. The patient was vaccinated against COVID-19 with Pfizer-BioNTech vaccine seven days before the onset. On initial computed tomography (CT) scan, the pc-ASPECTS was 10 and CT angiography (CTA) showed the tip of BA thrombosis. Intravenous thrombolytic therapy was administered, followed by MT, achieving mTICI 3 and NIHSS 5 after the procedure. Within 24 hours from the first MT, there was neurological deterioration followed by coma. Urgent CT/CTA was performed and rethrombosis of BA was confirmed with pc-ASPECTS 10. MT was repeated with mTICI 2b. Stroke etiology was undetermined. After 17 days, the patient was discharged and referred to continue rehabilitation treatment. After 90 days of stroke, his NIHSS was 2 and mRS 1. We can consider that early recurrent BAO can be successfully treated with repeated MT.

Venous Thromboembolism After COVID-19 Infection Among People With and Without Immune-Mediated Inflammatory Diseases

Importance

Immune-mediated inflammatory diseases (IMIDs) and COVID-19 are independently associated with venous thromboembolisms (VTEs).

Objective

To determine if individuals with IMIDs are at higher risk of VTE following COVID-19 infection compared with individuals without IMIDs.

Design, Setting, and Participants

Population-based matched cohort study using multiple deterministically linked health administrative databases from Ontario, Canada, and including patients testing positive for COVID-19 between January 1, 2020, and December 30, 2021, and followed up until March 31, 2022. Individuals with IMIDs (n = 28 440) who tested positive for COVID-19 were matched with up to 5 individuals without an IMID (n = 126 437) who tested positive for COVID-19. Matching was based on year of birth, sex, neighborhood income, and rural/urban residence. Data analysis was performed from August 6, 2022, to August 21, 2023.

Exposure

Diagnosis of an IMID, identified using algorithms based on diagnostic codes, procedures, and specialist visits.

Main Outcome and Measure

The main outcome was estimated age- and sex-standardized incidence of VTE. Proportional cause-specific hazard models compared the risk of VTE in people with and without IMIDs. Death was a competing risk. Models adjusted for history of VTE, 2 or more doses of a COVID-19 vaccine 14 or more days prior to COVID-19 diagnosis, and the Charlson Comorbidity Index. Routinely collected health data were used, so the hypothesis tested was formulated after data collection but prior to being granted access to data.

Results

The study included 28 440 individuals (16 741 [58.9%] female; 11 699 [41.1%] male) with an IMID diagnosed prior to first COVID-19 diagnosis, with a mean (SD) age of 52.1 (18.8) years at COVID-19 diagnosis. These individuals were matched to 126 437 controls without IMIDs. The incidence of VTE within 6 months of COVID-19 diagnosis among 28 440 individuals with an IMID was 2.64 (95% CI, 2.23-3.10) per 100 000 person-days compared with 2.18 (95% CI, 1.99-2.38) per 100 000 person-days among 126 437 matched individuals without IMIDs. The VTE risk was not statistically significantly different among those with vs without IMIDs (adjusted hazard ratio, 1.12; 95% CI, 0.95-1.32).

Conclusions and Relevance

In this retrospective population-based cohort study of individuals with IMIDs following COVID-19, individuals with IMIDs did not have a higher risk of VTE compared with individuals without an IMID. These data provide reassurance to clinicians caring for individuals with IMIDs and COVID-19.

Systemic Anticancer Therapy and Thromboembolic Outcomes in Hospitalized Patients With Cancer and COVID-19

Importance

Systematic data on the association between anticancer therapies and thromboembolic events (TEEs) in patients with COVID-19 are lacking.

Objective

To assess the association between anticancer therapy exposure within 3 months prior to COVID-19 and TEEs following COVID-19 diagnosis in patients with cancer.

Design, Setting, and Participants

This registry-based retrospective cohort study included patients who were hospitalized and had active cancer and laboratory-confirmed SARS-CoV-2 infection. Data were accrued from March 2020 to December 2021 and analyzed from December 2021 to October 2022.

Exposure

Treatments of interest (TOIs) (endocrine therapy, vascular endothelial growth factor inhibitors/tyrosine kinase inhibitors [VEGFis/TKIs], immunomodulators [IMiDs], immune checkpoint inhibitors [ICIs], chemotherapy) vs reference (no systemic therapy) in 3 months prior to COVID-19.

Main Outcomes and Measures

Main outcomes were (1) venous thromboembolism (VTE) and (2) arterial thromboembolism (ATE). Secondary outcome was severity of COVID-19 (rates of intensive care unit admission, mechanical ventilation, 30-day all-cause mortality following TEEs in TOI vs reference group) at 30-day follow-up.

Results

Of 4988 hospitalized patients with cancer (median [IQR] age, 69 [59-78] years; 2608 [52%] male), 1869 had received 1 or more TOIs. Incidence of VTE was higher in all TOI groups: endocrine therapy, 7%; VEGFis/TKIs, 10%; IMiDs, 8%; ICIs, 12%; and chemotherapy, 10%, compared with patients not receiving systemic therapies (6%). In multivariable log-binomial regression analyses, relative risk of VTE (adjusted risk ratio [aRR], 1.33; 95% CI, 1.04-1.69) but not ATE (aRR, 0.81; 95% CI, 0.56-1.16) was significantly higher in those exposed to all TOIs pooled together vs those with no exposure. Among individual drugs, ICIs were significantly associated with VTE (aRR, 1.45; 95% CI, 1.01-2.07). Also noted were significant associations between VTE and active and progressing cancer (aRR, 1.43; 95% CI, 1.01-2.03), history of VTE (aRR, 3.10; 95% CI, 2.38-4.04), and high-risk site of cancer (aRR, 1.42; 95% CI, 1.14-1.75). Black patients had a higher risk of TEEs (aRR, 1.24; 95% CI, 1.03-1.50) than White patients. Patients with TEEs had high intensive care unit admission (46%) and mechanical ventilation (31%) rates. Relative risk of death in patients with TEEs was higher in those exposed to TOIs vs not (aRR, 1.12; 95% CI, 0.91-1.38) and was significantly associated with poor performance status (aRR, 1.77; 95% CI, 1.30-2.40) and active/progressing cancer (aRR, 1.55; 95% CI, 1.13-2.13).

Conclusions and Relevance

In this cohort study, relative risk of developing VTE was high among patients receiving TOIs and varied by the type of therapy, underlying risk factors, and demographics, such as race and ethnicity. These findings highlight the need for close monitoring and perhaps personalized thromboprophylaxis to prevent morbidity and mortality associated with COVID-19-related thromboembolism in patients with cancer.

Risk of retinal vein occlusion following COVID-19 vaccination: a self-controlled case series

BACKGROUND

To evaluate the association between COVID-19 vaccination and retinal vein occlusion (RVO).

METHODS

This multicentre self-controlled case series included patients with RVO seen in five tertiary referral centres in Italy. All adults who received at least one dose of the BNT162b2, ChAdOx1 nCoV-19, mRNA-1273 or Ad26.COV2.S vaccine and had a first diagnosis of RVO between January 01, 2021, and December 31, 2021 were included. Incidence rate ratios (IRRs) of RVO were estimated using Poisson regression, comparing rates of events in a 28-day period following each dose of vaccination and in the unexposed control periods.

RESULTS

210 patients were included in the study. No increased risk of RVO was observed after the first dose (1-14 days IRR: 0.87, 95% CI: 0.41-1.85; 15-28 days IRR: 1.01, 95% CI: 0.50-2.04; 1-28 days IRR: 0.94, 95% CI: 0.55-1.58) and second dose of vaccination (1-14 days IRR: 1.21, 95% CI: 0.62-2.37; 15-28 days IRR: 1.08, 95% CI: 0.53-2.20; 1-28 days IRR: 1.16, 95% CI: 0.70-1.90). No association between RVO and vaccination was found in subgroup analyses by type of vaccine, gender and age.

CONCLUSIONS

This self-controlled case series found no evidence of an association between RVO and COVID-19 vaccination.

Retinal vein occlusion in the general population after COVID-19 vaccination and infection

INTRODUCTION

Retinal vein occlusion (RVO) is mostly a consequence of vascular risk factors (VRF). COVID-19 vaccines have been related to vascular and thrombotic events (VTE).

OBJECTIVE

To assess the RVO incidence in the general population in our health area and the possible relation with COVID-19 infection and vaccination.

METHODS

Demographic features, classic VRF, thrombophilia data, COVID-19 status, and Framingham risk score were collected prospectively.

RESULTS

472 consecutive patients studied over 13 years with RVO were included (Valdecilla Cohort). Classic VRFs were present in 90%, antiphospholipid syndrome in 12.3%, and genetic thrombophilia in 13.5%. Ninety-one percent of RVO patients were vaccinated and 6.8% suffered COVID-19 infection. In the cohort, no patient had a new RVO after vaccination or infection. In the general population, 20 subjects had RVO after receiving the vaccine (0.006%). Overall, 8 cases occurred in the first-month post-vaccination and 12 after 30 days. In the early and late groups, there are 3 and 4 patients respectively, with a low-intermediate risk Framingham score. Twenty-nine patients in the cohort suffered SARS-CoV-2 infection, twenty-seven of them had RVO before infection. Two patients with low-risk Framingham scores had RVO after infection, one of them early (<1 month).

CONCLUSIONS

Vaccination and COVID-19 might be involved in the development of RVO in some cases, mainly in patients without VRF, thrombophilia, or chronic inflammatory conditions and with a lower Framingham score, especially in the first month after vaccination or infection.

Research progress of NF-κB signaling pathway and thrombosis

Venous thromboembolism is a very common and costly health problem. Deep-vein thrombosis (DVT) can cause permanent damage to the venous system and lead to swelling, ulceration, gangrene, and other symptoms in the affected limb. In addition, more than half of the embolus of pulmonary embolism comes from venous thrombosis, which is the most serious cause of death, second only to ischemic heart disease and stroke patients. It can be seen that deep-vein thrombosis has become a serious disease affecting human health. In recent years, with the deepening of research, inflammatory response is considered to be an important pathway to trigger venous thromboembolism, in which the transcription factor NF-κB is the central medium of inflammation, and the NF-κB signaling pathway can regulate the pro-inflammatory and coagulation response. Thus, to explore the mechanism and make use of it may provide new solutions for the prevention and treatment of thrombosis.

Risk of Thrombosis Following the First Dose of ChAdOx1 nCoV-19 Vaccine in Patients Undergoing Maintenance Hemodialysis: A Self-Controlled Case Series Study

Background

The ChAdOx1 nCoV-19 vaccine is associated with vaccine-induced thrombosis and thrombocytopenia (VITT). Patients with end-stage renal disease (ESRD) under hemodialysis are at elevated risk of heparin-induced thrombocytopenia, which shares similar mechanisms with VITT. We aimed to examine the risk of VITT after the first dose of ChAdOx1 nCoV-19 vaccine using a self-controlled case series analysis (SCCS) in the hemodialyzed ESRD population.

Methods

Drawing from the largest multi-center electronic medical records database in Taiwan, we identified adult patients, with or without hemodialysis, between 1st December, 2020, and 31st December, 2021, who received a first dose of ChAdOx1 nCoV-19 vaccine and had an outcome of thrombocytopenia, venous thrombosis, or arterial thrombosis. We calculated the incident rate ratios (IRRs) of outcomes in different periods at risk, compared to periods not at risk.

Results

 We identified 59 hemodialysis patients and 41 non-dialysis patients with an outcome. The SCCS analyses showed, for the hemodialysis group, a significantly increased risk of outcomes during the period 31 to 60 days post-exposure to ChAdOx1 nCoV-19 vaccine (IRR: 2.823; 95% CI: 1.423-5.600). However, in non-dialysis patients there was no increase in risks during any of the post-exposure risk periods.

Conclusion

For ESRD patients under hemodialysis, the first dose of ChAdOx1 nCoV-19 vaccine was associated with a 2.8-fold increase in risk of thrombosis.

COVID-19 thromboembolism is reduced in ambulatory, but not hospitalized patients, following COVID-19 vaccination

Not available.

Thrombocytopenic, thromboembolic and haemorrhagic events following second dose with BNT162b2 and ChAdOx1: self-controlled case series analysis of the English national sentinel cohort

Background

Thrombosis associated with thrombocytopenia was a matter of concern post first and second doses of BNT162b2 and ChAdOx1 COVID-19 vaccines. Therefore, it is important to investigate the risk of thrombocytopenic, thromboembolic and haemorrhagic events following a second dose of BNT162b2 and ChAdOx1 COVID-19 vaccines.

Methods

We conducted a large-scale self-controlled case series analysis, using routine primary care data linked to hospital data, among 12.3 million individuals (16 years old and above) in England. We used the nationally representative Oxford-Royal College of General Practitioners (RCGP) sentinel network database with baseline and risk periods between 8th December 2020 and 11th June 2022. We included individuals who received two vaccine (primary) doses of the BNT162b2 mRNA (Pfizer-BioNTech) and two vaccine doses of ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccines in our analyses. We carried out a self-controlled case series (SCCS) analysis for each outcome using a conditional Poisson regression model with an offset for the length of risk period. We reported the incidence rate ratios (IRRs) and 95% confidence intervals (CI) of thrombocytopenic, thromboembolic (including arterial and venous events) and haemorrhagic events, in the period of 0-27 days after receiving a second dose of BNT162b2 or ChAdOx1 vaccines compared to the baseline period (14 or more days prior to first dose, 28 or more days after the second dose and the time between 28 or more days after the first and 14 or more days prior to the second dose). We adjusted for a range of potential confounders, including age, sex, comorbidities and deprivation.

Findings

Between December 8, 2020 and February 11, 2022, 6,306,306 individuals were vaccinated with two doses of BNT162b2 and 6,046,785 individuals were vaccinated with two doses of ChAdOx1. Compared to the baseline, our analysis show no increased risk of venous thromboembolic events (VTE) for both BNT162b2 (IRR 0.71, 95% CI: 0.65-0.770) and ChAdOx1 (IRR 0.91, 95% CI: 0.84-0.98); and similarly there was no increased risk for cerebral venous sinus thrombosis (CVST) for both BNT162b2 (IRR 0.87, 95% CI: 0.41-1.85) and ChAdOx1 (IRR 1.73, 95% CI: 0.82-3.68). We additionally report no difference in IRR for pulmonary embolus, and deep vein thrombosis, thrombocytopenia, including idiopathic thrombocytopenic purpura (ITP), and haemorrhagic events post second dose for both BNT162b2.

Interpretation

Reassuringly, we found no associations between increased risk of thrombocytopenic, thromboembolic and haemorrhagic events post vaccination with second dose for either of these vaccines.

Funding

Data and Connectivity: COVID-19 Vaccines Pharmacovigilance study.

Pathophysiology, diagnosis, and management of neuroinflammation in covid-19

Although neurological complications of SARS-CoV-2 infection are relatively rare, their potential long term morbidity and mortality have a significant impact, given the large numbers of infected patients. Covid-19 is now in the differential diagnosis of a number of common neurological syndromes including encephalopathy, encephalitis, acute demyelinating encephalomyelitis, stroke, and Guillain-Barré syndrome. Physicians should be aware of the pathophysiology underlying these presentations to diagnose and treat patients rapidly and appropriately. Although good evidence has been found for neurovirulence, the neuroinvasive and neurotropic potential of SARS-CoV-2 is limited. The pathophysiology of most complications is immune mediated and vascular, or both. A significant proportion of patients have developed long covid, which can include neuropsychiatric presentations. The mechanisms of long covid remain unclear. The longer term consequences of infection with covid-19 on the brain, particularly in terms of neurodegeneration, will only become apparent with time and long term follow-up.