Outpatient and inpatient anticoagulation therapy and the risk for hospital admission and death among COVID-19 patients

Abstract

Background: Coronavirus disease 2019 (COVID-19) is associated with a hypercoagulable state. Limited data exist informing the relationship between anticoagulation therapy and risk for COVID-19 related hospitalization and mortality. Methods: We evaluated all patients over the age of 18 diagnosed with COVID-19 in a prospective cohort study from March 4th to August 27th, 2020 among 12 hospitals and 60 clinics of M Health Fairview system (USA). We investigated the relationship between (1) 90-day anticoagulation therapy among outpatients before COVID-19 diagnosis and the risk for hospitalization and mortality and (2) Inpatient anticoagulation therapy and mortality risk. Findings: Of 6195 patients, 598 were immediately hospitalized and 5597 were treated as outpatients. The overall case-fatality rate was 2 • 8% ( n = 175 deaths). Among the patients who were hospitalized, the inpatient mortality was 13%. Among the 5597 COVID-19 patients initially treated as outpatients, 160 (2.9%) were on anticoagulation and 331 were eventually hospitalized (5.9%). In a multivariable analysis, outpatient anticoagulation use was associated with a 43% reduction in risk for hospital admission, HR (95% CI = 0.57, 0.38-0.86), p = 0.007, but was not associated with mortality, HR (95% CI = 0.88, 0.50 -1.52), p = 0.64. Inpatients who were not on anticoagulation (before or after hospitalization) had an increased risk for mortality, HR (95% CI = 2.26, 1.17-4.37), p = 0.015. Interpretation: Outpatients with COVID-19 who were on outpatient anticoagulation at the time of diagnosis experienced a 43% reduced risk of hospitalization. Failure to initiate anticoagulation upon hospitalization or maintaining outpatient anticoagulation in hospitalized COVID-19 patients was associated with increased mortality risk.

Analysis of Deaths and Favorable Developments of Patients with SARS-CoV-2 Hospitalized in the Largest Hospital for Infectious Diseases and Pneumo-Phthisiology in the West of the Country

“… 63 The results of another prospective cohort study conducted on 6195 patients in 14 hospitals and 60 clinics in the United States show that SARS-CoV-2 is associated with a state of hypercoagulability and that the presence of cardiovascular, immunological and coagulatory comorbidities has been associated with a higher risk of death, especially for inpatients, ICUs and mechanically ventilated and non-ventilated patients. 64–66 …”

Thromboprophylaxis in people hospitalized with COVID‐19: Assessing intermediate or standard doses in a retrospective cohort study

“…Our findings add to a growing body of evidence that has failed to show benefits of intermediate‐dose thromboprophylaxis among adults hospitalized with COVID‐19. 7 , 11 , 22 , 23 , 24 , 25 , 26 , 27 A small clinical trial showed no difference in risk of thrombosis, ECMO, or death between standard and intermediate doses with weight‐based adjustments. 22 In our subgroup analyses, where we applied weight‐based adjustments, we again found increases in risk of therapeutic anticoagulation as a proxy for thrombosis, severe disease, and death.…”

Safety and Efficacy of Low Molecular Weight Heparin for Thromboprophylaxis in the Elderly: A Network Meta-Analysis of Randomized Clinical Trials

“…Furthermore, since the outbreak of COVID-19, LMWH has been widely used for anticoagulation in older COVID-19 patients (Kreidieh and Temraz, 2021). In patients with proximal DVT and PE, LMWHs are preferred over oral anticoagulants and UFH (Hozayen et al, 2021). In-hospital COVID-19 patients who were on anticoagulation with LMWHs or UFH had a significantly reduced risk of mortality (hazard ratio 2.26, 95% CI 1.17-4.37).…”