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Updated: Aug 9, 2026
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Computerized Dynamic Posturography for Postural Control Assessment in Patients with Intermittent Claudication
Published on: December 11, 2013
Variability in responsiveness to clopidogrel in patients with intermittent claudication
1Department of Vascular Surgery, University of Aberdeen, Aberdeen, Scotland, UK. k.cassar@abdn.ac.uk
Summary
Patients with intermittent claudication exhibit varied responses to clopidogrel. Some show no platelet activation reduction, while others respond excessively, necessitating further study on associated risks.
Area of Science:
- Cardiology
- Pharmacology
- Hematology
Background:
- Clopidogrel resistance is a known issue in cardiac patients.
- Platelet response variability in intermittent claudication (IC) is understudied.
Purpose of the Study:
- To investigate the antiplatelet effects of clopidogrel plus aspirin in IC patients.
- To assess ex vivo platelet activation variability in response to clopidogrel.
Main Methods:
- Analysis of data from a randomized controlled trial involving 67 IC patients.
- Measurement of ADP-stimulated fibrinogen binding via flow cytometry at baseline, 12 hours, and 30 days post-clopidogrel loading dose.
- Assessment of treatment compliance through tablet counts.
Main Results:
- 9.8% of patients showed no reduction in platelet activation 12 hours after loading dose, persisting at 30 days.
- Responders (n=55) had a mean fibrinogen binding reduction of 51.5%, with significant variability (8.11-97.7%).
- 6.6% of patients exhibited over 95% reduction in fibrinogen binding.
Conclusions:
- Patients with IC demonstrate substantial variability in clopidogrel response.
- A small subset of patients are non-responders (hypo-responders), while another small group are hyper-responders.
- Further clinical research is needed to determine risks of bleeding (hyper-responders) and thrombotic events (hypo-responders).
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