Real-World Management of Pharmacological Thromboprophylactic Strategies for COVID-19 Patients in Japan: From the CLOT-COVID Study

Background

Data on prophylactic anticoagulation are important in understanding the current issues, unmet needs, and optimal management of Japanese COVID-19 patients.

Objectives

This study aimed to investigate the clinical management strategies for prophylactic anticoagulation of COVID-19 patients in Japan.

Methods

The CLOT-COVID study was a multicenter observational study that enrolled 2,894 consecutive hospitalized patients with COVID-19. The study population consisted of 2,889 patients (after excluding 5 patients with missing data); it was divided into 2 groups: patients with pharmacological thromboprophylaxis (n = 1,240) and those without (n = 1,649). Furthermore, we evaluated the 1,233 patients who received prophylactic anticoagulation-excluding 7 patients who could not be classified based on the intensity of their anticoagulants-who were then divided into 2 groups: patients receiving prophylactic anticoagulant doses (n = 889) and therapeutic anticoagulant doses (n = 344).

Results

The most common pharmacological thromboprophylaxis anticoagulant was unfractionated heparin (68.2%). The severity of COVID-19 at admission was a predictor of the implementation of pharmacological thromboprophylaxis in the multivariable analysis (moderate vs mild: OR: 16.6; 95% CI:13.2-21.0; P < 0.001, severe vs mild: OR: 342.6, 95% CI: 107.7-1090.2; P < 0.001). It was also a predictor of the usage of anticoagulants of therapeutic doses in the multivariable analysis (moderate vs mild: OR: 2.10; 95% CI: 1.46-3.02; P < 0.001, severe vs mild: OR: 5.96; 95% CI: 3.91-9.09; P < 0.001).

Conclusions

In the current real-world Japanese registry, pharmacological thromboprophylaxis, especially anticoagulants at therapeutic doses, was selectively implemented in COVID-19 patients with comorbidities and severe COVID-19 status at admission.

Integral Use of Thromboelastography With Platelet Mapping to Guide Appropriate Treatment, Avoid Complications, and Improve Survival of Patients With Coronavirus Disease 2019-Related Coagulopathy

OBJECTIVES

Coagulopathy of coronavirus disease 2019 is largely described as hypercoagulability, yet both thrombotic and hemorrhagic complications occur. Although therapeutic and prophylactic anticoagulant interventions have been recommended, empiric use of antifactor medications (heparin/enoxaparin) may result in hemorrhagic complications, including death. Furthermore, traditional (antifactor) anticoagulation does not address the impact of overactive platelets in coronavirus disease 2019. The primary aim was to evaluate if algorithm-guided thromboelastography with platelet mapping could better characterize an individual's coronavirus disease 2019-relatedcoagulopathic state and, secondarily, improve outcomes.

DESIGN SETTING AND PATIENTS

Coronavirus disease 2019 patients (n = 100), receiving thromboelastography with platelet mapping assay upon admission to an 800-bed tertiary-care hospital, were followed prospectively by a hospital-based thromboelastography team. Treating clinicians were provided with the option of using a pre-established algorithm for anticoagulation, including follow-up thromboelastography with platelet mapping assays. Two groups evolved: 1) patients managed by thromboelastography with platelet mapping algorithm (algorithm-guided-thromboelastography); 2) those treated without thromboelastography with platelet mapping protocols (non-algorithm-guided). Outcomes included thrombotic/hemorrhagic complications, pulmonary failure, need for mechanical ventilation, acute kidney injury, dialysis requirement, and nonsurvival.

INTERVENTIONS

Standard-of-care therapy with or without algorithm-guided-thromboelastography support.

MEASUREMENTS AND MAIN RESULTS

Although d-dimer, C-reactive protein, and ferritin were elevated significantly in critically ill (nonsurvivors, acute kidney injury, pulmonary failure), they did not distinguish between coagulopathic and noncoagulopathic patients. Platelet hyperactivity (maximum amplitude-arachidonic acid/adenosine diphosphate > 50 min), with or without thrombocytosis, was associated with thrombotic/ischemic complications, whereas severe thrombocytopenia (platelet count < 100,000/μL) was uniformly fatal. Hemorrhagic complications were observed with decreased factor activity (reaction time > 8 min). Non-algorithm-guided patients had increased risk for subsequent mechanical ventilation (relative risk = 10.9; p < 0.0001), acute kidney injury (relative risk = 2.3; p = 0.0017), dialysis (relative risk = 7.8; p < 0.0001), and death (relative risk = 7.7; p < 0.0001), with 17 of 28 non-algorithm-guided patients (60.7%) dying versus four algorithm-guided-thromboelastography patients (5.6%) (p < 0.0001). Thromboelastography with platelet mapping-guided antiplatelet treatment decreased mortality 82% (p = 0.0002), whereas non-algorithm-guided (compared with algorithm-guided-thromboelastography) use of antifactor therapy (heparin/enoxaparin) resulted in 10.3-fold increased mortality risk (p = 0.0001).

CONCLUSIONS

Thromboelastography with platelet mapping better characterizes the spectrum of coronavirus disease 2019 coagulation-related abnormalities and may guide more tailored, patient-specific therapies in those infected with coronavirus disease 2019.