Blood Thinners Could Increase Survival in Hospitalized COVID-19 Patients

Valentin Fuster, MD, PhD

While we are still learning more and more about the impact of coronavirus disease 2019 (COVID-19) on cardiometabolic health, new research suggests use of anticoagulants could improve survival in hospitalized COVID-19 patients.

Using data Mount Sinai COVID Informatics Center, results of the study, which included more than 2500 patients with confirmed COVID-19 infections, indicated patients receiving anticoagulants had a lower rate of in-hospital mortality than those not receiving anticoagulants—with the difference becoming more apparent in cases requiring invasive mechanical ventilation.

“This research demonstrates anticoagulants taken orally, subcutaneously, or intravenously may play a major role in caring for COVID-19 patients, and these may prevent possible deadly events associated with coronavirus, including heart attack, stroke, and pulmonary embolism,” said investigator Valentin Fuster, MD, PhD, Director of Mount Sinai Heart and Physician-in-Chief of the Mount Sinai Hospital, in a statement from Mount Sinai.

With new research demonstrating an increased risk of thromboembolic events in COVID-19 patients and the impact of anticoagulation on disease management still unclear, Fuster and a team of colleagues sought to assess the association of in-hospital anticoagulant use on survival in hospitalized patients. Investigators used Cox proportional hazards models to assess treatment-dose systemic AC, including oral, subcutaneous, or intravenous forms, on in-hospital mortality.

Of note, the investigators’ analysis accounted for confounding factors including age, sex, ethnicity, body mass index, history of hypertension, heart failure, atrial fibrillation, type 2 diabetes, anticoagulant use before admission, and admission date. Additionally, anticoagulant treatment duration was used as a covariate to adjust for length of stay and initiation of anticoagulants.

For the analysis, investigators used a cohort of 2773 patients hospitalized within the Mount Sinai Health System between March 14-April 11, 2020 with laboratory-confirmed COVID-19. For the cohort, median hospitalization duration was 5 (3-8) days, median time from admission to anticoagulant initiation was 2 (0-5) days, and median duration of anticoagulant treatment was 3 (2-7)days.

Results indicated an in-hospital mortality rate of 22.5% for patients treated with anticoagulants compared to 22.8% in patients who did not receive them—median survival for these groups was 21 days and 14, respectively. Results also demonstrated patients receiving anticoagulants were more likely to require invasive mechanical ventilation than those not receiving anticoagulants (29.8% vs 8.1%; P <.001).

Investigators highlighted significantly increased baseline prothrombin time, activated partial thromboplastin time, lactate dehydrogenase, ferritin, C-reactive protein, and D-dimer values in patients who received in-hospital anticoagulation, but none of these differences were observed in patients who required mechanical ventilation.

Among the 395 individuals requiring mechanical ventilation, patients receiving anticoagulants had an in-hospital mortality rate of 29.1% and a median survival of 21 days compared to 62.7% and 9 days, respectively, in patients not receiving anticoagulants. Results of the investigators’ multivariate proportional hazards model indicated longer duration of anticoagulant therapy was associated with reduced risk of mortality (aHR 0.86; 95% CI, 0.82-0.89; P <.001).

When examining the impact of anticoagulation on risk of bleeding events in these patients, investigators found 1.9% of patients not receiving anticoagulants experienced major bleeding compared to 3.0% of those receiving anticoagulants (P=.02). Among those receiving anticoagulants who experienced bleeding, 63% experienced the event after starting therapy and 37% had events before starting anticoagulation.

Investigators noted the observational nature of their study and caution against overinterpretation without considering its limitations.

“Using anticoagulants should be considered when patients get admitted to the ER and have tested positive for COVID-19 to possibly improve outcomes. However, each case should be evaluated on an individualized basis to account for potential bleeding risk,” said Fuster in the aforementioned statement.

This study, “Association of Treatment Dose Anticoagulation with In-Hospital Survival Among Hospitalized Patients with COVID-19,” was published in the Journal of the American College of Cardiology.