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Published on: February 28, 2012
Prophylactic Anticoagulation and Thrombosis in Hospitalized Patients with Clinically Stable COVID-19 at Admission:
Yugo Yamashita1, Sen Yachi2, Makoto Takeyama2
1Department of Cardiovascular Medicine, Kyoto University Hospital, Kyoto, Kyoto, Japan.
Insights
Prophylactic anticoagulation in stable hospitalized COVID-19 patients did not prevent thrombosis. Patients who worsened during hospitalization were more likely to receive anticoagulation and had a higher thrombosis risk.
Area of Science:
- Internal Medicine
- Infectious Diseases
- Cardiology
Background:
- The role of prophylactic anticoagulation in stable hospitalized COVID-19 patients remains debated.
- Observational studies are crucial for understanding real-world treatment effects.
Purpose of the Study:
- To evaluate the association between prophylactic anticoagulation and thrombosis risk in hospitalized patients with mild coronavirus disease 2019 (COVID-19).
Main Methods:
- A multicenter observational study (CLOT-COVID) analyzed 1738 hospitalized COVID-19 patients initially stable and not requiring oxygen.
- Patients were divided into two groups: those receiving prophylactic anticoagulation (n=326) and those not (n=1412).
Main Results:
- Patients receiving prophylactic anticoagulation showed a more severe COVID-19 course during hospitalization compared to those without.
- Thrombosis occurred in 0.5% of patients, with numerically higher rates in those with more severe COVID-19.
- Patients who did not worsen rarely developed thrombosis, regardless of anticoagulation status.
Conclusions:
- In stable hospitalized COVID-19 patients, prophylactic anticoagulation did not appear to reduce thrombosis risk.
- Worsening COVID-19 severity after admission was associated with increased anticoagulation use and a higher risk of thrombosis.
Abstract:
Objectives: The potential benefit of routine prophylactic anticoagulation for all hospitalized patients with clinically stable coronavirus disease 2019 (COVID-19) is still controversial. Method: The CLOT-COVID Study was a multicenter observational study enrolling 2894 consecutive hospitalized patients with COVID-19. The current study population consisted of 1738 hospitalized patients with mild COVID-19 at admission not requiring oxygen administration, who were divided into 2 groups: patients with prophylactic anticoagulation (n = 326) and those without (n = 1412). Results: Patients with prophylactic anticoagulation had more severe status of the worst severity of COVID-19 during hospitalization compared with those without (mild: 38% versus 82%, moderate: 55% versus 17%, and severe or death at discharge: 6.4% versus 0.7%, P <0.001). During hospitalization, 8 patients (0.5%) developed thrombosis, and the incidences of thrombosis were numerically higher in patients with more severe status of worst severity of COVID-19 during hospitalization (mild: 0.2%, moderate: 1.2%, and severe or death at discharge: 3.2%). Conclusions: Among hospitalized patients with clinically stable COVID-19 at admission, patients who did not worsen in COVID-19 severity after admission rarely developed thrombosis, although patients with worsening of COVID-19 severity after admission more often received prophylactic anticoagulation and might have a higher risk of thrombosis.
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