Molecular mechanisms for thrombosis risk in Black people: a role in excess mortality from COVID-19

Low molecular weight heparin use and thrombotic complications in upper gastrointestinal resection for malignancy in a multi-ethnic Asian population

OBJECTIVE

Epidemiological studies showed substantially lower venous thromboembolic event risk among Asians compared to Caucasians. Yet no Asian guidelines addresses thromboprophylaxis following major surgery for upper gastrointestinal (UGI) malignancy. We aim to evaluate effects of LMWH on thromboembolic and bleeding events in our population.

METHODS

A retrospective study of all UGI resections for malignancy performed in a tertiary institution in Singapore between 2008 and 2018 was performed. Demographics, clinicopathological data and treatment outcome data were collected and analyzed.

RESULTS

A total of 399 patients were included in the study. 210 (52.6%) received postoperative LMWH. Basic demographics-age, gender, BMI, smoking status were comparable. Most patients had cancers stage III or above (42.5% vs 34.6%) cancers. Patients who had open surgery were more likely to receive postoperative LMWH (81.8% vs 67.2%, p = 0.002). Postoperative mortality (3.2% vs 2.9%) and venous thromboembolic events (1.6% vs 1.4%) were similar. However, LMWH use was associated with increased blood transfusion (29.0% vs 12.7%, p < 0.001).

CONCLUSION

Incidence of venous thromboembolism was low and similar irrespective of postoperative LMWH use. However, LMWH use was associated with increased postoperative bleeding. Hence, we do not support routine LMWH for Asian patients undergoing UGI resection for malignancy.

A Retrospective Analysis of Vitamin D Levels in Hospitalized COVID-19 Patients With Suspected Pulmonary Embolism

Introduction Despite using anti-coagulation therapy in hospitalized coronavirus disease 2019 (COVID-19) patients, they have high rates of pulmonary embolism (PE) and deep vein thrombosis (DVT). The main objective of this study was to evaluate the association between vitamin D deficiency and thrombotic events (defined as the occurrence of a new PE or DVT) in hospitalized COVID-19 patients. Materials and Methods This was a retrospective, cross-sectional study of 208 hospitalized COVID-19 patients who received a computed tomographic pulmonary angiography (CTPA) based on clinical suspicion of PE between January 1, 2020, and February 5, 2021. A <20 ng/mL serum vitamin D level was used to categorize vitamin D deficiency. Nonparametric tests and multivariate binary logistic regression were used to evaluate the association between serum vitamin D levels and clinical outcomes. Results The mean vitamin D level was 26.7±13.0 ng/mL (n=208), and approximately one-third of patients were vitamin D deficient (n=68, 32.7%). No association was found between vitamin D deficiency and the occurrence of thrombotic events. The incidence of PE was 19.1% in vitamin D deficient patients compared to 11.4% in vitamin D sufficient patients (p=0.13). Vitamin D deficiency was positively associated with ICU admission (OR 3.047, 95%CI 1.57-5.91, p=0.001) and mortality (OR 3.76, 95%CI 1.29-11.01, p=0.016). Conclusions This study found no association between vitamin D deficiency and the occurrence of a new PE or DVT in hospitalized COVID-19 patients. Patients with vitamin D deficiency were more likely to be admitted to the ICU and had increased overall mortality.

Temporal Trends, Predictors, and Outcomes of Disseminated Intravascular Coagulation in Hospitalizations With Sepsis

Background

This retrospective study was conducted to analyze the temporal trends, predictors, and impact of disseminated intravascular coagulation (DIC) on outcomes among septicemic patients using a nationally representative database.

Methods

We derived data from the National Inpatient Sample (NIS) for the years 2008-2017 for adult hospitalizations due to sepsis. The primary outcomes were in-hospital mortality and discharge to facility. The Cochran-Armitage test and multivariable survey logistic regression models were used to analyze the data.

Results

Out of 12,820,000 hospitalizations due to sepsis, 153,181 (1.18%) were complicated by DIC. The incidence of DIC decreased from 2008 to 2017. In multivariable regression analysis, demographics and comorbidities were associated with higher odds of DIC. During the study period, in-hospital mortality among patients with sepsis decreased, but the attributable risk percent of in-hospital mortality due to DIC increased. We observed similar trends for discharge to facility; however, the adjusted odds of discharge to facility due to DIC remained stable over the study period.

Conclusion

Although the incidence of sepsis complicated by DIC decreased, the attributable in-hospital mortality rate due to DIC increased during the study period. We identified several predictors associated with the development of DIC in sepsis, some of which are potentially modifiable.

Disparities in Excess, All-Cause Mortality among Black, Hispanic, and White Veterans at the U.S. Department of Veterans Affairs during the COVID-19 Pandemic

Background: From 2019 to 2020, all-cause mortality in the U.S. increased, with most of the rise attributed to COVID-19. No studies have examined the racial disparities in all-cause mortality among U.S. veterans receiving medical care (VA users) at the U.S. Department of Veterans Affairs (VA) during the pandemic. Methods: In the present paper, we conduct a longitudinal study examining the differences in mortality among White, Black, and Hispanic veterans, aged 45 years and older, during the first, full year of the pandemic (March 2020–February 2021). We calculated the Standardized Mortality Rates (SMRs) per 100,000 VA users for each racial and ethnic group by age and gender. Results: The highest percentage increase between the number of deaths occurred between pre- and post-pandemic years (March 2020–February 2021 vs. March 2019–February 2020). For Hispanics, the all-cause mortality increased by 34%, while for Blacks, it increased by 32%. At the same time, we observed that an 18% increase in all-cause mortality occurred among Whites. Conclusion: Blacks and Hispanics were disproportionately affected by the COVID-19 pandemic, leading both directly and indirectly to higher all-cause mortality among these groups compared to Whites. Disparities in the all-cause mortality rates varied over time and across groups. Additional research is needed to examine which factors may account for the observed changes over time. Understanding those factors will permit the development of strategies to mitigate these disparities.

Cumulative Evidence for the Association of Thrombosis and the Prognosis of COVID-19: Systematic Review and Meta-Analysis

Background

Although thrombosis events have been reported in patients with coronavirus disease 2019 (COVID-19), the association between thrombosis and COVID-19-related critical status or risk of mortality in COVID-19 has been inconsistent.

Objective

We conducted a meta-analysis of reports assessing the association between thrombosis and the prognosis of COVID-19.

Methods

The EMBASE, Ovid-MEDLINE, and Web of Science databases were searched up to December 9, 2021, and additional studies were retrieved via manual searching. Studies were included if they reported the risk of COVID-19-related critical status or COVID-19-related mortality in relation to thrombosis. The related data were extracted by two authors independently, and a random effects model was conducted to pool the odds ratios (ORs). In addition, stratified analyses were conducted to evaluate the association.

Results

Among 6,686 initially identified studies, we included 25 studies published in 2020 and 2021, with a total of 332,915 patients according to predefined inclusion criteria. The associations between thrombosis and COVID-19-related mortality and COVID-19-related critical status were significant, with ORs of 2.61 (95% CI, 1.91–3.55, p < 0.05) and 2.9 (95% CI, 1.6–5.24, p < 0.05), respectively. The results were statistically significant and consistent in stratified analyses.

Conclusions

Thrombosis is associated with an increased risk of mortality and critical status induced by COVID-19. Further prospective studies with large sample sizes are required to establish whether these associations are causal by considering more confounders and to clarify their mechanisms.

Observational studies cannot prove causality. However, autopsy studies show thrombosis events preceding COVID-19-related deaths. The results of this meta-analysis reported that thrombosis was associated with a 161% increased risk of mortality from COVID-19 and a 190% increased risk of COVID-19-related critical status. The type of thrombosis included in the original studies also seemed to be related to the results.

Global control of COVID-19: good vaccines may not suffice

The COVID-19 pandemic has unveiled health and socioeconomic inequities around the globe. Effective epidemic control requires the achievement of herd immunity, where susceptible individuals are conferred indirect protection by being surrounded by immunized individuals. The proportion of people that need to be vaccinated to obtain herd immunity is determined through the herd immunity threshold. However, the number of susceptible individuals and the opportunities for contact between infectious and susceptible individuals influence the progress of an epidemic. Thus, in addition to vaccination, control of a pandemic may be difficult or impossible to achieve without other public health measures, including wearing face masks and social distancing. This article discusses the factors that may contribute to herd immunity and control of COVID-19 through the availability of effective vaccines and describes how vaccine effectiveness in the community may be lower than that expected. It also discusses how pandemic control in some countries and populations may face vaccine accessibility barriers if market forces strongly regulate the new technologies available, according to the inverse care law.

Association of Race with Early Outcomes of Elective Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis: Propensity-Matched and Subgroup Analysis

OBJECTIVE

To investigate the impact of race on 30-day postoperative complication rates of elective posterior spinal fusions (PSF) for adolescent idiopathic scoliosis (AIS).

METHODS

Patients who underwent PSF between 2012 and 2018 were reviewed from the American College of Surgeons National Surgical Quality Improvement Program pediatric database. Propensity score matching was utilized to evaluate whether patient race (i.e., black vs. white) was correlated with postoperative complications.

RESULTS

A total of 4051 PSF for AIS cases met criteria for inclusion. Of these, 3221 (79.5%) patients were white and 830 (20.5%) were black. Several baseline characteristics significantly differed between cohorts. Patients in the black cohort had a significantly higher body mass index, a greater proportion of female patients, higher ASA scores, preoperative diagnosis of asthma or cardiac risk factors, and prior use of steroids. The total number of vertebral segments fused was also greater in the black cohort. After controlling for differences in baseline characteristics with propensity score matching analysis, the only significant difference in morbidity and mortality identified was a higher incidence of venous thromboembolism among the black cohort (2.8% vs. 0.1%; P < 0.001).

CONCLUSIONS

In contrast to prior literature, our analysis did not identify black race as an independent risk factor for higher perioperative morbidity or mortality in patients of young age group undergoing elective PSF for AIS, except the higher incidence of venous thromboembolism. The findings of the present study suggest that previously reported perioperative morbidity and mortality outcomes in black patients may be secondary to baseline health characteristics, and not due to race itself.

Severe Acute Respiratory Syndrome-Associated Coronavirus 2 Infection and Organ Dysfunction in the ICU: Opportunities for Translational Research

OBJECTIVES

Since the beginning of the coronavirus disease 2019 pandemic, hundreds of thousands of patients have been treated in ICUs across the globe. The severe acute respiratory syndrome-associated coronavirus 2 virus enters cells via the angiotensin-converting enzyme 2 receptor and activates several distinct inflammatory pathways, resulting in hematologic abnormalities and dysfunction in respiratory, cardiac, gastrointestinal renal, endocrine, dermatologic, and neurologic systems. This review summarizes the current state of research in coronavirus disease 2019 pathophysiology within the context of potential organ-based disease mechanisms and opportunities for translational research.

DATA SOURCES

Investigators from the Research Section of the Society of Critical Care Medicine were selected based on expertise in specific organ systems and research focus. Data were obtained from searches conducted in Medline via the PubMed portal, Directory of Open Access Journals, Excerpta Medica database, Latin American and Caribbean Health Sciences Literature, and Web of Science from an initial search from December 2019 to October 15, 2020, with a revised search to February 3, 2021. The medRxiv, Research Square, and clinical trial registries preprint servers also were searched to limit publication bias.

STUDY SELECTION

Content experts selected studies that included mechanism-based relevance to the severe acute respiratory syndrome-associated coronavirus 2 virus or coronavirus disease 2019 disease.

DATA EXTRACTION

Not applicable.

DATA SYNTHESIS

Not applicable.

CONCLUSIONS

Efforts to improve the care of critically ill coronavirus disease 2019 patients should be centered on understanding how severe acute respiratory syndrome-associated coronavirus 2 infection affects organ function. This review articulates specific targets for further research.

Ethnic differences in thromboprophylaxis for COVID-19 patients: should they be considered?

Thromboembolic events contribute to morbidity and mortality in coronavirus disease 2019 (COVID-19). As a result, thromboprophylaxis using low-molecular-weight heparin (LMWH) is universally recommended for hospitalized patients based on multiple guidelines. However, ethnic differences with respect to thrombogenicity have been reported and the incidence of thromboembolic events is considered to be lower in the Asian population. Despite the importance of thromboprophylaxis, bleeding is also a side effect that should be considered. We examine the data relating to potential ethnic differences in thrombosis and bleeding in COVID-19. Although sufficient data is not yet available, current evidence does not oppose routine anticoagulant use and thromboprophylaxis using a standard dose of LMWH for admitted patients regardless of ethnicity based on our review.

Impact of Ethnicity on COVID-19 Related Hospitalizations in Children During the First Pandemic Wave in Northern Italy

There is increasing evidence that black people and other minorities have a higher incidence of severe COVID-19 disease, but little is known about the situation of children, especially in Europe. In general children are less infected and if so, frequently show mild or asymptomatic disease, making conclusions difficult. We collected data on SARS-CoV-2 associated hospitalizations in a well-defined population of 550,180 children up to 15 years in five hub-centers during the "first wave" at the heart of the pandemic in Northern Italy. Among the 451,053 Italian citizens 80 were hospitalized as compared to 31 out of 99,127 foreign citizens, giving a significantly higher risk (odds ratio 1.76; 95% CI: 1.16-2.66) for the foreign children. The risk was highest for children of African ethnicity as compared to Italians with an odds ratio of 2.76 (95% CI: 1.56-4.87). None of the patients deceased. There was no significant difference in age (thou infants regardless of ethnicity had a 10-fold higher risk), sex, length of hospitalization or comorbidities, namely overweight. As bureaucratic, cultural and information barriers mostly affect preventive and adult services and considering that in contrast to other countries, in Italy pediatric care is guaranteed free of (out-of-pocket) charge to all people <16 years, and hospitals are densely spaced, access to health care seems to be a minor problem. Thus, other possible root causes are discussed. We believe that this is an unbiased starting point to understand and overcome the reasons for the higher risk those children experience.

The effect of race on composite thrombotic events in patients with COVID-19

COVID-19 associated coagulopathy and mortality related to thrombotic complications have been suggested as biological mediators in racial disparities related to COVID-19. We studied the adjusted prevalence of acute ischemic stroke, pulmonary embolism, myocardial infarction, and deep venous thrombosis stratified by race in hospitalized patients in one New York City borough during the local COVID-19 surge. The multi-racial cohort included 4299 patients hospitalized with COVID-19, 9% of whom were white, 40% black, 41% Hispanic and 10% Asian or other. We found a 6.1% prevalence of composite thrombotic events. There were no significant race-specific differences in thrombotic events when adjusting for basic demographics, socioeconomic factors, medical comorbidities or biomarkers using a stepwise regression model. We therefore found no evidence that the racial disparities related to COVID-19, and specifically thrombotic complications, are caused by biological differences in race.

COVID-19 hospitalizations in Brazil's Unified Health System (SUS)

Objective

To study the profile of hospitalizations due to COVID-19 in the Unified Health System (SUS) in Brazil and to identify factors associated with in-hospital mortality related to the disease.

Methods

Cross-sectional study, based on secondary data on COVID-19 hospitalizations that occurred in the SUS between late February through June. Patients aged 18 years or older with primary or secondary diagnoses indicative of COVID-19 were included. Bivariate analyses were performed and generalized linear mixed models (GLMM) were estimated with random effects intercept. The modeling followed three steps, including: attributes of the patients; elements of the care process; and characteristics of the hospital and place of hospitalization.

Results

89,405 hospitalizations were observed, of which 24.4% resulted in death. COVID-19 patients hospitalized in the SUS were predominantly male (56.5%) with a mean age of 58.9 years. The length of stay ranged from less than 24 hours to 114 days, with a mean of 6.9 (±6.5) days. Of the total number of hospitalizations, 22.6% reported ICU use. The odds on in-hospital death were 16.8% higher among men than among women and increased with age. Black individuals had a higher likelihood of death. The behavior of the Charlson and Elixhauser indices was consistent with the hypothesis of a higher risk of death among patients with comorbidities, and obesity had an independent effect on increasing this risk. Some states, such as Amazonas and Rio de Janeiro, had a higher risk of in-hospital death from COVID-19. The odds on in-hospital death were 72.1% higher in municipalities with at least 100,000 inhabitants, though being hospitalized in the municipality of residence was a protective factor.

Conclusion

There was broad variation in COVID-19 in-hospital mortality in the SUS, associated with demographic and clinical factors, social inequality, and differences in the structure of services and quality of health care.

Potential impact on coagulopathy of gene variants of coagulation related proteins that interact with SARS-CoV-2

Thrombosis has been one of the complications of the Coronavirus disease of 2019 (COVID-19), often associated with poor prognosis. There is a well-recognized link between coagulation and inflammation, however, the extent of thrombotic events associated with COVID-19 warrants further investigation. Poly(A) Binding Protein Cytoplasmic 4 (PABPC4), Serine/Cysteine Proteinase Inhibitor Clade G Member 1 (SERPING1) and Vitamin K epOxide Reductase Complex subunit 1 (VKORC1), which are all proteins linked to coagulation, have been shown to interact with SARS proteins. We computationally examined the interaction of these with SARS-CoV-2 proteins and, in the case of VKORC1, we describe its binding to ORF7a in detail. We examined the occurrence of variants of each of these proteins across populations and interrogated their potential contribution to COVID-19 severity. Potential mechanisms by which some of these variants may contribute to disease are proposed. Some of these variants are prevalent in minority groups that are disproportionally affected by severe COVID-19. Therefore, we are proposing that further investigation around these variants may lead to better understanding of disease pathogenesis in minority groups and more informed therapeutic approaches.

Author summary

Increased blood clotting, especially in the lungs, is a common complication of COVID-19. Infectious diseases cause inflammation which in turn can contribute to increased blood clotting. However, the extent of clot formation that is seen in the lungs of COVID-19 patients suggests that there may be a more direct link. We identified three human proteins that are involved indirectly in the blood clotting cascade and have been shown to interact with proteins of SARS virus, which is closely related to the novel coronavirus. We examined computationally the interaction of these human proteins with the viral proteins. We looked for genetic variants of these proteins and examined how these variants are distributed across populations. We investigated whether variants of these genes could impact severity of COVID-19. Further investigation around these variants may provide clues for the pathogenesis of COVID-19 particularly in minority groups.