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1262 Estimating the Burden of Venous and Arterial Thrombotic Events in Hospitalized Adults with COVID-19; A National Multicenter Cohort Study

Program: Oral and Poster Abstracts
Session: 331. Thrombotic Microangiopathies/Thrombocytopenias and COVID-19-Related Thrombotic/Vascular Disorders: Clinical and Epidemiological: Poster I
Hematology Disease Topics & Pathways:
Clinical Practice (Health Services and Quality)
Saturday, December 9, 2023, 5:30 PM-7:30 PM

Rushad Patell, MBBS1, Dana E. Angelini, MD2, Stacy R Ellsworth3*, Paul Lewis4*, James C Lee5*, Edith A. Nutescu5*, Alpesh Amin6*, Daniel M Witt, PharmD7*, Marisol Betensky, MD8, Neil Goldenberg, MD, PhD8, Peter Kouides9, Doaa Attia, MD, MBBS10*, Lyla Mourany10*, Leslie Lake11*, Rachel P. Rosovsky, MD12, Alok A. Khorana, MD13 and Scott Kaatz, DO, MSc14*

1Division of Medical Oncology and Hematology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
2Taussig Cancer Institute, Department of Hematology and Medical Oncology, Cleveland Clinic, Cleveland, OH
3Henry Ford Health System, Detroit
4Baycare Health System, Clearwater, FL
5University of Illinois, Chicago, IL
6University of California, Irvine, CA
7University of Utah, Salt Lake City, UT
8Johns Hopkins All Children's Hospital, Saint Petersburg, FL
9University of Rochester, Rochester, NY
10Cleveland Clinic Foundation, Cleveland, OH
11National Blood Clot Alliance, Philadelphia, PA
12Division of Hematology & Oncology, Department of Medicine, Massachusetts General Hospital, Boston, MA
14Division of Hospital Medicine, Henry Ford Health, Detroit, MI


Patients infected with Coronavirus Disease 2019 (COVID-19) have clinical and laboratory features consistent with a hypercoaguable state, particularly in more severely ill patients that require hospitalization. However, estimates of thrombotic complications in this high risk population vary widely. A geographic representative cohort to explore the rates of thrombotic events in patients hospitalized with COVID-19 in the United States would be useful to better understand the burden of thrombosis in this population. We aimed to assess the rates of venous and arterial thrombosis events during hospitalization in patients with COVID-19 in a national multicenter cohort study.


We conducted a retrospective cohort study of hospitalized patients diagnosed with COVID-19 from January 1 2020 to January 2023. IRB approval was obtained at each site. Inclusion criteria included adults (> 21 years), hospitalized for >1 day and laboratory confirmation of polymerase chain reaction testing of severe acute respiratory syndrome coronavirus 2. Data were extracted by participating centers in a pre-specified instrument from the electronic medical record at each institution and pooled prior to analysis. Data sources included manual extraction by study investigators in 7 sites and electronic extraction based on billing codes at one site (Cleveland Clinic). Primary outcome was venous thrombotic events, including deep vein thrombosis (DVT), pulmonary embolism (PE). Unusual sites including splanchnic vein thrombosis and cerebral venous thrombosis were included if objectively demonstrated on imaging. Arterial thrombotic events including ischemic stroke, acute coronary syndrome were included as secondary outcomes. Data are presented as proportions, with binomial 95% confidence intervals (CI).


We included 33,769 patients from eight medical centers across the United States. Participating hospitals included all four census regions from the North East (Beth Israel Deaconess Medical Center, MA (n=1021) Rochester Regional Hospital, NY (n=99)), South (John Hopkins Medical Institute, ML (n=334); Baycare Health System, FL (n=3734), MidWest (Cleveland Clinic Foundation, OH (n=25467); Henry Ford Health System, MI (973); University of Illinois, IL (1192)) and West (University of California, CA (n=613)). (Figure)

Of the total 33,433 hospitalized patients with COVID-19 included, 1684 patients developed a venous thrombotic event during the index hospitalization (5.0%, 95% CI 4.8-5.2) and 261 developed an arterial thrombotic event (0.8%, 95% CI, 95% CI 0.7-0.9). Rates of venous events by individual sites ranged from 2.6-8% and arterial events from 0.3-6.6%.


In this national multicenter cohort study that included academic and community hospitals from all four US census regions, we estimated the rates of VTE were over five times more frequent than arterial events in hospitalized patients with COVID-19. Accurate estimates of thrombotic rates and trends can help plan targeted interventions related to strategies around thromboprophylaxis interventions and resource allocation for future surges of COVID-19 cases.

Disclosures: Betensky: Janssen Pharmaceuticals: Consultancy, Honoraria. Goldenberg: University of Colorado-affiliated Academic Research Organization CPC Clinical Research: Other: Serves on clinical trials oversite committees for pharma studies; Chiesi: Consultancy; Boehringer-Ingelheim: Consultancy; Bayer: Consultancy; Novartis: Other: Data and Safety Monitoring Committee; Daiichi Sankyo: Consultancy; Astra Zeneca: Consultancy; Anthos Therapeutics: Consultancy. Rosovsky: Penumbra: Consultancy, Other: National Lead Investigator for STORM PE; Inari: Consultancy; Janssen: Consultancy, Other: Research funding is to my institution, Research Funding; Abbott: Consultancy; Dova: Consultancy; BMS: Consultancy; Pulmonary Embolism Response Team: Membership on an entity's Board of Directors or advisory committees, Other: President-Elect. Khorana: Pfizer: Honoraria; Sanofi: Honoraria; Anthos: Honoraria; WebMD: Honoraria; BMS: Honoraria; Bayer: Honoraria; Janssen: Honoraria. Kaatz: Osmosis Research: Research Funding; Janssen: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria; AstraZeneca: Honoraria; PhaseBio: Honoraria; Gilead: Honoraria; AC Forum: Membership on an entity's Board of Directors or advisory committees; National Blood Clot Alliance: Membership on an entity's Board of Directors or advisory committees; PERT Consortium: Membership on an entity's Board of Directors or advisory committees.

*signifies non-member of ASH