Lo Re V 3rd, Dutcher SK, Connolly JG, Perez-Vilar S, Carbonari DM, DeFor TA, Djibo DA, Harrington LB, Hou L, Hennessy S, Hubbard RA, Kempner ME, Kuntz JL, McMahill-Walraven CN, Mosley J, Pawloski PA, Petrone AB, Pishko AM, Rogers Driscoll M, Steiner CA, Zhou Y, and Cocoros NM
Objective: To measure the 90 day risk of arterial thromboembolism and venous thromboembolism among patients diagnosed with covid-19 in the ambulatory (ie, outpatient, emergency department, or institutional) setting during periods before and during covid-19 vaccine availability and compare results to patients with ambulatory diagnosed influenza., Design: Retrospective cohort study., Setting: Four integrated health systems and two national health insurers in the US Food and Drug Administration's Sentinel System., Participants: Patients with ambulatory diagnosed covid-19 when vaccines were unavailable in the US (period 1, 1 April-30 November 2020; n=272 065) and when vaccines were available in the US (period 2, 1 December 2020-31 May 2021; n=342 103), and patients with ambulatory diagnosed influenza (1 October 2018-30 April 2019; n=118 618)., Main Outcome Measures: Arterial thromboembolism (hospital diagnosis of acute myocardial infarction or ischemic stroke) and venous thromboembolism (hospital diagnosis of acute deep venous thrombosis or pulmonary embolism) within 90 days after ambulatory covid-19 or influenza diagnosis. We developed propensity scores to account for differences between the cohorts and used weighted Cox regression to estimate adjusted hazard ratios of outcomes with 95% confidence intervals for covid-19 during periods 1 and 2 versus influenza., Results: 90 day absolute risk of arterial thromboembolism with covid-19 was 1.01% (95% confidence interval 0.97% to 1.05%) during period 1, 1.06% (1.03% to 1.10%) during period 2, and with influenza was 0.45% (0.41% to 0.49%). The risk of arterial thromboembolism was higher for patients with covid-19 during period 1 (adjusted hazard ratio 1.53 (95% confidence interval 1.38 to 1.69)) and period 2 (1.69 (1.53 to 1.86)) than for patients with influenza. 90 day absolute risk of venous thromboembolism with covid-19 was 0.73% (0.70% to 0.77%) during period 1, 0.88% (0.84 to 0.91%) during period 2, and with influenza was 0.18% (0.16% to 0.21%). Risk of venous thromboembolism was higher with covid-19 during period 1 (adjusted hazard ratio 2.86 (2.46 to 3.32)) and period 2 (3.56 (3.08 to 4.12)) than with influenza., Conclusions: Patients diagnosed with covid-19 in the ambulatory setting had a higher 90 day risk of admission to hospital with arterial thromboembolism and venous thromboembolism both before and after covid-19 vaccine availability compared with patients with influenza., Competing Interests: Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/disclosure-of-interest/ and declare: VLR reports research grants to his institution from the US Food and Drug Administration (FDA) during the conduct of the study and personal consulting fees from Takeda outside the submitted work. DAD reports contract research funding from FDA Sentinel Initiative via Harvard Pilgrim Health Care Institute. LBH reports contract research funding from FDA Sentinel Initiative during the conduct of the study and grants from Kaiser Permanente Garfield Memorial Fund for covid-19 related research outside the submitted work. SH reports grants from FDA, Pfizer, and Johnson & Johnson during the conduct of the study, consulting for Novo Nordisk, Arbor Pharmaceuticals, the Medullary Thyroid Cancer Consortium (Novo Nordisk, AstraZeneca, GlaxoSmithKline, and Eli Lilly), Biogen, Intercept Pharmaceuticals, Provention Bio, bluebird bio, and Amylyx Pharmaceuticals, and is a special government employee of the FDA. RAH reports grants from FDA during the conduct of the study and grants from Merck, Pfizer, and Johnson & Johnson outside of the submitted work. CNM-W works for CVS Health Clinical Trial Services LLC, an affiliate of CVS Health. She is responsible for CVS Health Clinical Trial Services activities with the FDA Sentinel Initiative, including both the Sentinel Program and BEST Program, and other Distributed Research Networks that use Sentinel infrastructure to analyze health claims data administered by Aetna, also a CVS Health affiliate. The Distributed Research Networks include Academy of Managed Care Pharmacy’s Biologics and Biosimilars Collective Intelligence Collaborative; Reagan-Udall’s Foundation IMEDS multisite research service agreements funded by Abbvie, Merck, Novartis, and Pfizer; Patient Centered Outcomes Research Institute; Research Action for Health Network; TherapeuticsMD; National Evaluation System for Health Technology Coordinating Center; and, Harvard Pilgrim Health Care Institute multisite research subcontracts funded by FDA, National Institutes of Health, Pfizer, Janssen, and GSK. To the best of her knowledge, CNM-W is not aware that any of these professional roles or activities create a conflict of interest with this project; however, she is itemizing them here for purposes of full disclosure. PAP reports contract funding support from HPHCI during the conduct of the study and outside the submitted work. AMP reports research funding to her institution from FDA during the conduct of the study and research funding from Sanofi Genzyme Research to her institution outside of the submitted work. NMC reports research funding from FDA via an HHS contract during the conduct of the study and funding from Harvard Pilgrim Health Care Institute (a non-profit organization that conducts work for government and private organizations, including pharmaceutical companies) outside of the submitted work. All other authors report no competing interest., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. 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