Risk of admission to hospital with arterial or venous thromboembolism among patients diagnosed in the ambulatory setting with covid-19 compared with influenza: retrospective cohort study
Sean Hennessy,
Rebecca A Hubbard,
Vincent Lo Re,
Dena M Carbonari,
Claudia A Steiner,
Yunping Zhou,
Cheryl N McMahill-Walraven,
Pamala A Pawloski,
Laura Hou,
Sarah K Dutcher,
John G Connolly,
Silvia Perez-Vilar,
Terese A DeFor,
Djeneba Audrey Djibo,
Laura B Harrington,
Maria E Kempner,
Jennifer L Kuntz,
Jolene Mosley,
Andrew B Petrone,
Allyson M Pishko,
Meighan Rogers Driscoll,
Noelle M Cocoros
Affiliations
Sean Hennessy
2 Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
Rebecca A Hubbard
2 Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
Vincent Lo Re
1 Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
Dena M Carbonari
2 Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
Claudia A Steiner
10 Kaiser Permanente Colorado Institute for Health Research, Aurora, CO, USA
Yunping Zhou
11 Humana Healthcare Research, Inc, Louisville, KY, USA
Cheryl N McMahill-Walraven
7 CVS Health Clinical Trial Services, an affiliate of Aetna, CVS Health Company, Blue Bell, PA, USA
Pamala A Pawloski
6 HealthPartners Institute, Bloomington, MN, USA
Laura Hou
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Sarah K Dutcher
3 Office of Surveillance and Epidemiology, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, USA
John G Connolly
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Silvia Perez-Vilar
3 Office of Surveillance and Epidemiology, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, USA
Terese A DeFor
6 HealthPartners Institute, Bloomington, MN, USA
Djeneba Audrey Djibo
7 CVS Health Clinical Trial Services, an affiliate of Aetna, CVS Health Company, Blue Bell, PA, USA
Laura B Harrington
8 Kaiser Permanente Washington Health Research Institute and Department of Epidemiology, University of Washington, Seattle, WA, USA
Maria E Kempner
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Jennifer L Kuntz
Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon, USA
Jolene Mosley
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Andrew B Petrone
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Allyson M Pishko
1 Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
Meighan Rogers Driscoll
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
Noelle M Cocoros
4 Department of Population Medicine, Harvard Medical School, Boston, MA, USA
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.
