Stroke risk reduction with oral anticoagulation using CHA2DS2-VASc in a Japanese AF population: A modeling analysis

Area of Science:

• Cardiology
• Stroke Prevention
• Pharmacology

Background:

• Current guidelines recommend CHA2DS2-VASc score for ischaemic stroke risk stratification in nonvalvular atrial fibrillation (NVAF) patients to guide antithrombotic therapy.
• Non-Vitamin K Oral Anticoagulants (NOACs) are preferred for NVAF patients with a CHA2DS2-VASc score of 1 or higher.
• The 2014 Japanese Circulation Society (JCS) guidelines do not recommend the CHA2DS2-VASc score for NVAF stroke risk assessment.

Purpose of the Study:

• To evaluate the impact of the JCS approach on stroke prevention in atrial fibrillation (AF).
• To model the effect of adopting a CHA2DS2-VASc score-based decision-making strategy for stroke prevention in Japanese NVAF patients.
• To estimate the number of potentially preventable stroke events using different oral anticoagulant strategies.

Main Methods:

• Calculated ischaemic stroke incidence in NVAF patients not on oral anticoagulants (OAC) using both CHADS2 and CHA2DS2-VASc scores.
• Utilized published Japanese data for the calculations.
• Estimated the number of preventable stroke events based on modeling.

Main Results:

• A CHA2DS2-VASc-based approach predicted fewer annual stroke events (e.g., 4369 for dabigatran 150 mg) compared to a CHADS2-based approach.
• The CHA2DS2-VASc approach identified potential annual stroke events in Japan estimated at 889,000 across various NOACs.
• The CHADS2 score-based approach resulted in a significantly higher number of potential stroke events for each agent.

Conclusions:

• Modeling analysis indicates that a CHA2DS2-VASc-based strategy offers enhanced opportunities for stroke prevention in Japanese NVAF patients.
• Adopting the CHA2DS2-VASc score can improve antithrombotic treatment decisions for stroke risk reduction in this population.