COVID-19 and antiphospholipid antibodies.

Antiphospholipid syndrome and the coagulopathy of COVID-19 share many pathophysiologic features, including endotheliopathy, hypercoagulability, and activation of platelets, complement pathways, and neutrophil extracellular traps, all acting in concert via a model of immunothrombosis. Antiphospholipid antibody production in COVID-19 is common, with 50% of COVID-19 patients being positive for lupus anticoagulant in some studies, and with non-Sapporo criteria antiphospholipid antibodies being prevalent as well. The biological significance of antiphospholipid antibodies in COVID-19 is uncertain, as such antibodies are usually transient, and studies examining clinical outcomes in COVID-19 patients with and without antiphospholipid antibodies have yielded conflicting results. In this review, we explore the biology of antiphospholipid antibodies in COVID-19 and other infections and discuss mechanisms of thrombogenesis in antiphospholipid syndrome and parallels with COVID-19 coagulopathy. In addition, we review the existing literature on safety of COVID-19 vaccination in patients with antiphospholipid antibodies and antiphospholipid syndrome.

Thrombosis questions from the inpatient wards.

The multifaceted pathophysiologic processes that comprise thrombosis and thromboembolic diseases take on a particular urgency in the hospitalized setting. In this review, we explore 3 cases of thrombosis from the inpatient wards: purpura fulminans, cancer-associated thrombosis with thrombocytopenia, and coronavirus disease 2019 (COVID-19) and the use of dose-escalated anticoagulation therapy and antiplatelet agents. We discuss the evaluation and management of purpura fulminans and the roles of plasma transfusion, protein C and antithrombin replacement, and anticoagulation in treating this disease. We present a framework for evaluating the etiologies of thrombocytopenia in cancer and review 2 strategies for anticoagulation management in patients with cancer-associated thrombosis and thrombocytopenia, including recent prospective data supporting the use of dose-modified anticoagulation based on platelet count. Last, we dissect the major clinical trials of therapeutic- and intermediate-dose anticoagulation and antiplatelet therapy in hospitalized patients with COVID-19, reviewing key recommendations from consensus guidelines while highlighting ways in which institutional and patient-tailored practices regarding antithrombotic therapies in COVID-19 may differ. Together, the cases highlight the diverse and dramatic presentations of macro- and microvascular thrombosis as encountered on the inpatient wards.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: January 2022 update on the use of therapeutic-intensity anticoagulation in acutely ill patients.

BACKGROUND: COVID-19-related acute illness is associated with an increased risk of venous thromboembolism (VTE). OBJECTIVE: These evidence-based guidelines from the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in making decisions about the use of anticoagulation in patients with COVID-19. METHODS: ASH formed a multidisciplinary guideline panel that included patient representatives and applied strategies to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process and performed systematic evidence reviews (through November 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations, which were subject to public comment. This is an update to guidelines published in February 2021 as part of the living phase of these guidelines. RESULTS: The panel made one additional recommendation. The panel issued a conditional recommendation in favor of therapeutic-intensity over prophylactic-intensity anticoagulation in patients with COVID-19-related acute illness who do not have suspected or confirmed VTE. The panel emphasized the need for an individualized assessment of risk of thrombosis and bleeding. The panel also noted that heparin (unfractionated or low molecular weight) may be preferred because of a preponderance of evidence with this class of anticoagulants. CONCLUSION: This conditional recommendation was based on very low certainty in the evidence, underscoring the need for additional, high-quality, randomized controlled trials comparing different intensities of anticoagulation in patients with COVID-19-related acute illness.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: July 2021 update on postdischarge thromboprophylaxis.

BACKGROUND: COVID-19-related acute illness is associated with an increased risk of venous thromboembolism (VTE). OBJECTIVE: These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for thromboprophylaxis in patients with COVID-19 who do not have confirmed or suspected VTE. METHODS: ASH formed a multidisciplinary guideline panel, including 3 patient representatives, and applied strategies to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including performing systematic evidence reviews (up to March 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the grading of recommendations assessment, development, and evaluation (GRADE) approach to assess evidence and make recommendations, which were subject to public comment. RESULTS: The panel agreed on 1 additional recommendation. The panel issued a conditional recommendation against the use of outpatient anticoagulant prophylaxis in patients with COVID-19 who are discharged from the hospital and who do not have suspected or confirmed VTE or another indication for anticoagulation. CONCLUSIONS: This recommendation was based on very low certainty in the evidence, underscoring the need for high-quality randomized controlled trials assessing the role of postdischarge thromboprophylaxis. Other key research priorities include better evidence on assessing risk of thrombosis and bleeding outcomes in patients with COVID-19 after hospital discharge.

Impact of COVID-19 on Hematology-Oncology Trainees: A Quantitative and Qualitative Assessment.

PURPOSE: Graduate medical and research training has drastically changed during the COVID-19 pandemic, with widespread implementation of virtual learning, redeployment from core rotations to the care of patients with COVID-19, and significant emotional and physical stressors. The specific experience of hematology-oncology (HO) fellows during the COVID-19 pandemic is not known. METHODS: We conducted a mixed-methods study using a survey of Likert-style and open-ended questions to assess the training experience and well-being of HO fellows, including both clinical and postdoctoral trainee members of the American Society of Hematology and ASCO. RESULTS: A total of 2,306 surveys were distributed by e-mail; 548 (23.8%) fellows completed the survey. Nearly 40% of fellows felt that they had not received adequate mental health support during the pandemic, and 22% reported new symptoms of burnout. Pre-existing burnout before the pandemic, COVID-19-related clinical work, and working in a primary research or nonclinical setting were associated with increased burnout on multivariable logistic regression. Qualitative thematic analysis of open-ended responses revealed significant concerns about employment after training completion, perceived variable quality of virtual education and board preparation, loss of clinical opportunities to prepare for independent clinical practice, inadequate grant funding opportunities in part because of shifting research priorities, variable productivity, and mental health or stress during the pandemic. CONCLUSION: HO fellows have been profoundly affected by the pandemic, and our data illustrate multiple avenues for fellowship programs and national organizations to support both clinical and postdoctoral trainees.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: May 2021 update on the use of intermediate-intensity anticoagulation in critically ill patients.

BACKGROUND: COVID-19-related critical illness is associated with an increased risk of venous thromboembolism (VTE). OBJECTIVE: These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in making decisions about the use of anticoagulation for thromboprophylaxis in patients with COVID-19-related critical illness who do not have confirmed or suspected VTE. METHODS: ASH formed a multidisciplinary guideline panel that included 3 patient representatives and applied strategies to minimize potential bias from conflicts of interest. The McMaster University Grading of Recommendations Assessment, Development and Evaluation (GRADE) Centre supported the guideline development process by performing systematic evidence reviews (up to 5 March 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the GRADE approach to assess evidence and make recommendations, which were subject to public comment. This is an update on guidelines published in February 2021. RESULTS: The panel agreed on 1 additional recommendation. The panel issued a conditional recommendation in favor of prophylactic-intensity over intermediate-intensity anticoagulation in patients with COVID-19-related critical illness who do not have confirmed or suspected VTE. CONCLUSIONS: This recommendation was based on low certainty in the evidence, which underscores the need for additional high-quality, randomized, controlled trials comparing different intensities of anticoagulation in critically ill patients. Other key research priorities include better evidence regarding predictors of thrombosis and bleeding risk in critically ill patients with COVID-19 and the impact of nonanticoagulant therapies (eg, antiviral agents, corticosteroids) on thrombotic risk.

Admission Rothman Index, Aspirin, and Intermediate Dose Anticoagulation Effects on Outcomes in COVID-19: A Multi-Site Propensity Matched Analysis

Introduction: Venous thromboembolism and in-situ small vessel thrombosis are increased in hospitalized patients with COVID-19 in several patient cohorts. Endotheliopathy and activation of both platelets and coagulation predict critical illness and death. For these reasons the use of anti-platelet agents and increased-intensity anticoagulation in the care of hospitalized patients with COVID-19 is under intense study in several clinical trials. We sought to examine the impact of aspirin and anticoagulation on hospitalization outcomes.Methods: We examined outcomes in a large multi-site cohort of consecutive, hospitalized, COVID-19 laboratory confirmed patients under a risk-stratified treatment algorithm from March 13 through June 18, with a focus on efficacy of aspirin and/or increased-intensity anticoagulation. Out of 4150 identified hospitalized patients with COVID-19, we created 3 study cohorts. The overall cohort (2785 patients) excluded pediatric patients, those with incomplete electronic data, and those with multiple admissions. The aspirin (1956 patients) and anticoagulation (1623 patients) cohorts were nested within the overall cohort;the former excluded patients on any home anti-platelet therapy or those who received non-aspirin anti-platelet therapy in the hospital, while the latter excluded patients who did not receive prophylactic or intermediate dose anticoagulation in the hospital. The primary outcome was in-hospital death. Secondary outcomes were time-to-death with a competing risk (time-to-hospital-discharge), escalation to ICU, length-of-stay and use of mechanical ventilation. Variables examined included age, gender, BMI, race, Rothman Index (RI), D-dimer (DD) and patient co-morbidities including cardiovascular disease, chronic kidney disease, and prior VTE. The aspirin and anticoagulation cohorts underwent propensity score (PS) matching utilizing variables found to be significant in multivariable regression modeling in the overall cohort with 638 and 386 patients, respectively.Results: Univariate followed by multivariable regression modeling in the 2785 patient overall cohort established a novel role for RI, and independent roles for age, BMI, and maximum DD, in predicting severity of illness. In all cohorts the 50th and lower percentile of admission RI was predictive of mortality in multivariable modeling (i.e. aspirin: 3rd and 4th admission RI quartiles with HR = 0.18 for both, p<0.001 for both). In PS matched patients, aspirin was associated with a significant decrease in mortality (OR 0.65 [0.42, 0.98], p=0.044) and a significant increase in mechanical ventilation (OR 1.49 [1.03, 2.18], p=0.037) and ICU status (OR = 1.45 [1.06, 1.98], p=0.021). In PS matched patients in the anticoagulation cohort, intermediate versus prophylactic dose anticoagulation was associated with a marginal decrease in mortality (OR 0.60, p=0.053). In the aspirin cohort examining in-hospital death and discharge as competing risks, the use of aspirin was associated with decreased mortality (p=0.042) and had no effect on discharge (p=0.31). In the anticoagulation cohort a similar competing risk model showed the use of intermediate rather than prophylactic anticoagulation decreased mortality (p=0.046) and had no effect on discharge (p = 0.21).Conclusion: We show in a large cohort of consecutively hospitalized patients with COVID-19 treated under a risk-stratified algorithm the prognostic utility of the admission RI in assessing outcomes in hospitalized patients with COVID-19 and a potential benefit of aspirin therapy on in-hospital death from COVID-19. A potential albeit marginal benefit of intermediate dose anticoagulation over prophylactic dose anticoagulation merits further study with results of clinical trials awaited.Figure

American Society of Hematology 2021 guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19)-related critical illness and acute illness are associated with a risk of venous thromboembolism (VTE). OBJECTIVE: These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for thromboprophylaxis for patients with COVID-19-related critical illness and acute illness who do not have confirmed or suspected VTE. METHODS: ASH formed a multidisciplinary guideline panel and applied strict management strategies to minimize potential bias from conflicts of interest. The panel included 3 patient representatives. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic evidence reviews (up to 19 August 2020). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including GRADE Evidence-to-Decision frameworks, to assess evidence and make recommendations, which were subject to public comment. RESULTS: The panel agreed on 2 recommendations. The panel issued conditional recommendations in favor of prophylactic-intensity anticoagulation over intermediate-intensity or therapeutic-intensity anticoagulation for patients with COVID-19-related critical illness or acute illness who do not have confirmed or suspected VTE. CONCLUSIONS: These recommendations were based on very low certainty in the evidence, underscoring the need for high-quality, randomized controlled trials comparing different intensities of anticoagulation. They will be updated using a living recommendation approach as new evidence becomes available.

Intermediate-dose anticoagulation, aspirin, and in-hospital mortality in COVID-19: A propensity score-matched analysis.

Thrombotic complications occur at high rates in hospitalized patients with COVID-19, yet the impact of intensive antithrombotic therapy on mortality is uncertain. We examined in-hospital mortality with intermediate- compared to prophylactic-dose anticoagulation, and separately with in-hospital aspirin compared to no antiplatelet therapy, in a large, retrospective study of 2785 hospitalized adult COVID-19 patients. In this analysis, we established two separate, nested cohorts of patients (a) who received intermediate- or prophylactic-dose anticoagulation ("anticoagulation cohort", N = 1624), or (b) who were not on home antiplatelet therapy and received either in-hospital aspirin or no antiplatelet therapy ("aspirin cohort", N = 1956). To minimize bias and adjust for confounding factors, we incorporated propensity score matching and multivariable regression utilizing various markers of illness severity and other patient-specific covariates, yielding treatment groups with well-balanced covariates in each cohort. The primary outcome was cumulative incidence of in-hospital death. Among propensity score-matched patients in the anticoagulation cohort (N = 382), in a multivariable regression model, intermediate- compared to prophylactic-dose anticoagulation was associated with a significantly lower cumulative incidence of in-hospital death (hazard ratio 0.518 [0.308-0.872]). Among propensity-score matched patients in the aspirin cohort (N = 638), in a multivariable regression model, in-hospital aspirin compared to no antiplatelet therapy was associated with a significantly lower cumulative incidence of in-hospital death (hazard ratio 0.522 [0.336-0.812]). In this propensity score-matched, observational study of COVID-19, intermediate-dose anticoagulation and aspirin were each associated with a lower cumulative incidence of in-hospital death.