Original Article

Netherlands Heart Journal

, Volume 19, Issue 6, pp 279-284

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Is platelet inhibition due to thienopyridines increased in elderly patients, in patients with previous stroke and patients with low body weight as a possible explanation of an increased bleeding risk?

  • N. J. BreetAffiliated withDepartment of Cardiology, St. Antonius HospitalSt. Antonius Center for Platelet Function Research
  • , H. E. van DonkersgoedAffiliated withSt. Antonius Center for Platelet Function Research
  • , J. W. van WerkumAffiliated withDepartment of Cardiology, St. Antonius HospitalSt. Antonius Center for Platelet Function Research
  • , H. J. BoumanAffiliated withDepartment of Cardiology, St. Antonius HospitalSt. Antonius Center for Platelet Function Research
  • , J. C. KelderAffiliated withDepartment of Cardiology, St. Antonius HospitalSt. Antonius Center for Platelet Function Research
  • , F. ZijlstraAffiliated withDepartment of Cardiology, Erasmus Medical Centre
  • , C. M. HackengAffiliated withSt. Antonius Center for Platelet Function ResearchDepartment of Clinical Chemistry, St. Antonius Hospital
  • , J. M. ten BergAffiliated withDepartment of Cardiology, St. Antonius HospitalSt. Antonius Center for Platelet Function Research Email author 

Abstract

Background

The TRITON-TIMI 38 study has identified three subgroups of patients with a higher risk of bleeding during treatment with the thienopyridine prasugrel: patients with a history of stroke or transient ischaemic attack (TIA), patients ≥75 years and patients with a body weight <60 kg. However, the underlying pathobiology leading to this increased bleeding risk remains to be elucidated. The higher bleeding rate may be due to a stronger prasugrel-induced inhibition of platelet aggregation in these subgroups. The aim of the present study was to determine whether on-treatment platelet reactivity is lower in these risk subgroups as compared with other patients in a large cohort on the thienopyridine clopidogrel undergoing elective coronary stenting.

Methods

A total of 1069 consecutive patients were enrolled. On-clopidogrel platelet reactivity was measured in parallel by light transmittance aggregometry, the VerifyNow® P2Y12 assay and the PFA-100 collagen/ADP cartridge.

Results

Fourteen patients (1.5%) had a prior history of stroke or TIA, 138 patients (14.5%) were older than 75 years and 30 patients (3.2%) had a body weight <60 kg. Age ≥ 75 years and a history of stroke were independent predictors of a higher on-treatment platelet reactivity. In contrast, a body weight <60 kg was significantly associated with a lower on-treatment platelet reactivity.

Conclusion

In two high-risk subgroups for bleeding, patients ≥ 75 years and patients with previous stroke, on-clopidogrel platelet reactivity is increased. In contrast, in patients with a low body weight, on-clopidogrel platelet reactivity is decreased, suggesting that a stronger response to a thienopyridine might only lead to more bleeds in patients with low body weight

Keywords

Clopidogrel Platelet reactivity