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Published on: November 26, 2013
Primary thromboprophylaxis in ambulatory symptomatic patients with COVID-19: a systematic review and meta-analysis of
Davide Di Vece1,2,3, Marco Valgimigli4, Elliot Barnathan5
1Department of Internal Medicine B, University Medicine Greifswald, Greifswald, Germany.
Insights
Primary thromboprophylaxis in COVID-19 outpatients reduced venous thromboembolism but did not impact hospitalization or death rates. The low absolute risk reduction suggests routine use may not be warranted.
Area of Science:
- Medicine
- Pharmacology
- Public Health
Background:
- COVID-19 pandemic necessitates strategies to improve patient outcomes, especially in outpatient settings.
- Thromboembolic events are a significant concern in COVID-19 patients.
- Identifying effective preventative measures for outpatients is crucial.
Purpose of the Study:
- To evaluate the efficacy and safety of primary thromboprophylaxis in outpatients diagnosed with COVID-19.
- To assess the impact of prophylactic anticoagulation on clinical outcomes in this population.
Main Methods:
- Systematic review and meta-analysis adhering to PRISMA guidelines.
- Comprehensive literature search of major databases (PubMed, ClinicalTrials.gov, Embase, CENTRAL) up to December 2023.
- Inclusion of seven randomized controlled trials involving 3758 symptomatic COVID-19 outpatients comparing prophylactic anticoagulation with placebo or standard care.
Main Results:
- Thromboprophylaxis did not significantly alter rates of all-cause hospitalization or mortality (RR 1.00; 95% CI 0.77-1.31).
- A significant reduction in venous thromboembolism (VTE) was observed (RR 0.28; 95% CI 0.08-0.94), representing a 0.6% absolute risk reduction.
- The number needed to treat (NNT) to prevent one VTE event was 174.
Conclusions:
- Primary thromboprophylaxis in symptomatic COVID-19 outpatients effectively reduces the risk of venous thromboembolism.
- The treatment showed no significant effect on hospitalization or mortality rates within 30 days.
- The modest absolute risk reduction for VTE suggests that routine thromboprophylaxis may not be universally supported for all COVID-19 outpatients.
Background:
The global impact of the COVID-19 pandemic has prompted the search for strategies to improve outcomes in affected individuals, including those initially managed in outpatient settings. Thromboembolic events have been reported as a concerning complication.
Objectives:
The aim of this study was to evaluate efficacy and safety of primary thromboprophylaxis in outpatients with COVID-19. The study protocol was registered in PROSPERO (CRD42022362776).
Methods:
The study adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and conducted a comprehensive search of PubMed/MEDLINE, ClinicalTrials.gov, and OVID/Embase and CENTRAL from Cochrane for studies up to December 11, 2023, without language restrictions. Randomized controlled trials comparing prophylactic-dose anticoagulation with placebo or standard of care in symptomatic outpatients with COVID-19 were included in this analysis. The primary outcome was the composite of all-cause hospitalization and death within 30 days. Secondary outcomes included venous thromboembolism, the composite of venous thromboembolism and major arterial cardiovascular events, and the individual components of the primary outcome.
Results:
Seven randomized controlled trials and 3758 COVID-19 outpatients were included. When compared with placebo or standard of care, thromboprophylaxis was associated with similar rates of all-cause hospitalization or mortality (relative risk, 1.00; 95% CI, 0.77-1.31) and lower rates of venous thromboembolism (relative risk, 0.28; 95% CI, 0.08-0.94), corresponding to a 0.6% absolute risk reduction and number needed to treat of 174.
Conclusion:
Thromboprophylaxis in symptomatic COVID-19 outpatients led to reduction in venous thromboembolism risk, with no impact on hospitalization or death. However, the overall low absolute risk reduction may not support its routine use.
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