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Stability of vitamin K antagonist anticoagulation after COVID-19 diagnosis

Eleonora Camilleri1, Nienke van Rein1,2, Felix J M van der Meer3,4

  • 1Department of Clinical Epidemiology Leiden University Medical Center Leiden The Netherlands.

Research and Practice in Thrombosis and Haemostasis
|October 20, 2021
PubMed

Insights

Coronavirus disease 2019 (COVID-19) significantly destabilizes vitamin K antagonist (VKA) therapy, leading to reduced time in therapeutic range (TTR). Increased monitoring is recommended for COVID-19 patients on VKAs to ensure anticoagulation stability.

Area of Science:

  • Internal Medicine
  • Pharmacology
  • Infectious Diseases

Background:

  • Coagulopathy is a known complication in severe COVID-19 cases.
  • The impact of COVID-19 on anticoagulation stability in outpatient VKA therapy remains unclear.

Purpose of the Study:

  • To evaluate the stability of vitamin K antagonist (VKA) therapy in patients diagnosed with COVID-19.
  • To assess the impact of COVID-19 on international normalized ratio (INR) control in patients on VKA therapy.

Main Methods:

  • A case-crossover study design was employed.
  • Data were collected from two anticoagulant clinics in the Netherlands between February and July 2020.
  • International normalized ratios (INRs) were analyzed for 26 weeks prior to and 12 weeks after COVID-19 diagnosis to calculate time in therapeutic range (TTR) and variance growth rate (VGR).

Main Results:

  • Fifty-one COVID-19 patients (mean age 84) showed a significant decrease in mean TTR from 80% before infection to 59% in the 6 weeks post-infection.
  • The period post-infection saw a 38% time above therapeutic range and a 4.4-fold increased risk of INR ≥5.0 compared to the pre-infection period.
  • Anticoagulation stability improved between 6 and 12 weeks post-infection, with TTR returning to 79%.

Conclusions:

  • COVID-19 is strongly associated with reduced therapeutic stability and time in therapeutic range (TTR) for patients on VKA therapy.
  • Increased vigilance and monitoring of anticoagulation are crucial for patients with COVID-19 undergoing VKA treatment.
  • The findings underscore the need for proactive management of anticoagulation in COVID-19 patients to prevent adverse events.
Abstract

Keywords:
COVID‐19anticoagulantscoronaviruscoumarinsinternational normalized ratioprothrombin time

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