Anticoagulants Linked with Improved In-hospital Survival of COVID-19

A new pre-proof study in the Journal of the American College of Cardiology suggests that treatment doses of certain anticoagulants are associated with improvements in in-hospital survival in patients infected with COVID-19.

A study conducted by researchers in the Mount Sinai Health System in New York City looked at 2,773 patients hospitalized with laboratory-diagnosed COVID-19. The researchers then used Cox proportional hazards models to determine the association between treatment-specific systemic anticoagulation (oral, subcutaneous or intravenous forms) and in-hospital mortality. The authors adjusted for age, sex, ethnicity, body mass index, hypertension history, heart failure, atrial fibrillation, type 2 diabetes mellitus, prior anticoagulation use, and admission date.

Of the 2,773 patients hospitalized with COVID-19, 28% (n=786) were given systemic anticoagulation during their hospital stay. The median hospital stay duration was five and time from admission to anticoagulation was two days, and median duration of anticoagulation was three days. The researchers reported the in-hospital mortality for anticoagulated patients to be 22.5% with a median survival of 21 days, compared to 22.8% (mean survival of 14 days) for patients not receiving anticoagulation. They also reported that patients receiving anticoagulation were more likely to required invasive mechanical ventilation (29.8% vs. 8.1%; P<0.001). In patients receiving mechanical ventilation, in-hospital mortality was higher in patients not treated with anticoagulation compared with those who received it (62.7% vs. 29.1%). In a multivariate proportional hazards model, longer anticoagulation duration was associated with a reduced risk of in-hospital mortality (adjusted HR=0.86 per day; 95% CI, 0.82 to 0.89; P<0.001).

“Although limited by its observational nature, unobserved confounding, unknown indication for anticoagulation, lack of metrics to further classify illness severity in the mechanically ventilated subgroup, and indication bias, our findings suggest that systemic anticoagulation may be associated with improved outcomes among patients hospitalized with COVID-19,” the authors wrote in the paper. “The potential benefits of systemic anticoagulation, however, need to be weighed against the risk of bleeding and therefore should be individualized. The association of in-hospital anticoagulation and mechanical ventilation likely reflects the reservation of anticoagulation for more severe clinical presentations. Interestingly, there was an association with anticoagulation and improved survival after adjusting for mechanical ventilation.”