Can platelet function tests predict the clinical efficacy of aspirin?

Area of Science:

• Cardiology
• Hematology
• Pharmacology

Background:

• Aspirin is a widely used antiplatelet medication.
• Aspirin resistance or nonresponsiveness describes individuals with a diminished or absent antiplatelet effect.
• The clinical significance of aspirin nonresponsiveness for predicting vascular events is not fully established.

Purpose of the Study:

• To review the current understanding of aspirin nonresponsiveness.
• To assess the clinical significance of aspirin nonresponsiveness.
• To evaluate the utility of current platelet function tests for monitoring aspirin therapy.

Main Methods:

• Review of existing literature on aspirin resistance and platelet function tests.
• Analysis of data from clinical trials investigating aspirin nonresponsiveness.
• Evaluation of the reliability and interchangeability of various platelet function assays.

Main Results:

• Several studies indicate that certain individuals exhibit reduced or absent platelet inhibition by aspirin.
• A direct relationship between aspirin nonresponsiveness and adverse vascular events is suggested by limited prospective trials.
• Most available platelet function tests lack the reliability and standardization needed for routine clinical use.

Conclusions:

• Aspirin nonresponsiveness is a recognized phenomenon, but its clinical impact requires further investigation.
• Current platelet function tests are not suitable for routine monitoring of antiplatelet therapy efficacy.
• There is a critical need for a simple, reliable assay to predict the clinical effectiveness of aspirin.