AVK overdose in Covid-19 infected patients

Area of Science:

• Internal Medicine
• Infectious Diseases
• Pharmacology

Background:

• Vitamin K antagonists (AVK) are commonly used anticoagulants requiring regular monitoring via International Normalized Ratio (INR).
• The COVID-19 pandemic, caused by SARS-CoV-2, has been associated with various clinical manifestations, including coagulopathy.

Purpose of the Study:

• To investigate the effect of COVID-19 infection on INR levels in patients treated with AVK.
• To assess the potential risk of bleeding complications in this patient population.

Main Methods:

• Retrospective analysis of four elderly patients (mean age 90 years) admitted during the COVID-19 pandemic.
• Patients were on stable, fixed doses of AVK for long-term therapy.
• SARS-CoV-2 infection was confirmed via RT-PCR, and INR levels were monitored closely before and after diagnosis.

Main Results:

• All four patients tested positive for SARS-CoV-2 and exhibited a substantial increase in INR.
• INR levels rose significantly even after discontinuation of AVK treatment in some cases.
• Observed INR increases ranged from 1.82 to 8.05, indicating a potential for excessive anticoagulation.

Conclusions:

• COVID-19 infection may lead to an unexpected increase in INR in patients treated with AVK, posing a hemorrhagic risk.
• Consideration should be given to alternative anticoagulation strategies or more frequent INR monitoring in COVID-19 patients on AVK.
• An unexplained rise in INR during the pandemic should prompt testing for SARS-CoV-2 infection.