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Circadian variations of platelet reactivity on clopidogrel in patients treated with elective percutaneous coronary

Michele Mattia Viscusi1, Fabio Mangiacapra2, Simone Circhetta1

  • 1Unit of Cardiovascular Science, Department of Medicine, Campus Bio-Medico University, Via Álvaro del Portillo, 200-00128, Rome, Italy.

Journal of Thrombosis and Thrombolysis
|April 21, 2022
PubMed

Insights

Platelet reactivity in patients on clopidogrel therapy after percutaneous coronary intervention (PCI) shows significant diurnal variation. Early morning assessments revealed higher platelet aggregation, indicating potential issues with standard morning dosing for chronic coronary syndrome (CCS).

Area of Science:

  • Cardiovascular Medicine
  • Pharmacology
  • Circadian Biology

Background:

  • Limited evidence exists on diurnal variations in platelet reactivity for patients on clopidogrel undergoing elective percutaneous coronary intervention (PCI) for chronic coronary syndrome (CCS).
  • Standard clopidogrel administration timing may not ensure consistent antiplatelet effects throughout the day.

Purpose of the Study:

  • To investigate potential diurnal variations in platelet reactivity among patients with stable coronary artery disease (CAD) on clopidogrel therapy post-elective PCI.
  • To assess the impact of clopidogrel timing on ADP-dependent platelet aggregation.

Main Methods:

  • Prospective enrollment of 15 patients with stable CAD on clopidogrel for at least 8 days, with medication administered at 8 a.m.
  • Assessment of ADP-dependent platelet aggregation at different times of the day (6 a.m. and 6 p.m.).
  • Statistical analysis to determine diurnal variations and significance.

Main Results:

  • Significant heterogeneity in diurnal levels of ADP-dependent platelet aggregation was observed (p = 0.0004).
  • Platelet reactivity peaked at the 6 a.m. assessment, significantly higher than afternoon (6 p.m.) levels (255 ± 66 vs 184 ± 67, p = 0.002).
  • A high proportion of patients (53.3%) exhibited high platelet reactivity during early-morning assessments.

Conclusions:

  • Clopidogrel-induced platelet inhibition in patients with CCS after elective PCI follows a circadian rhythm.
  • Standard morning administration of clopidogrel may lead to inconsistent and inadequate antiplatelet inhibition, particularly in the early morning.

Keywords:
Circadian rhythmClopidogrelPlatelet reactivityPlateletsStable coronary artery disease

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