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A comparison of clopidogrel responsiveness in patients with versus without chronic renal failure

Sang Hyun Park1, Weon Kim, Chung Su Park

  • 1Cardiovascular Center, Gwangju Veterans Hospital, Republic of Korea.

The American Journal of Cardiology
|October 21, 2009
PubMed

Insights

Platelet responsiveness to clopidogrel is reduced in patients with chronic renal failure. Increasing the clopidogrel dosage did not improve platelet inhibition in these patients.

Area of Science:

  • Pharmacology
  • Nephrology
  • Cardiology

Background:

  • Clopidogrel is an antiplatelet medication commonly used in patients with cardiovascular disease.
  • Chronic renal failure (CRF) can affect drug metabolism and response.
  • Understanding clopidogrel's efficacy in CRF patients is crucial for optimizing treatment.

Purpose of the Study:

  • To compare platelet responsiveness to clopidogrel in patients with CRF versus those with normal renal function.
  • To evaluate the effect of increased clopidogrel dosage on platelet inhibition in CRF patients.

Main Methods:

  • Prospective, randomized, open-label, single-center trial.
  • Compared 23 patients with normal renal function (75 mg clopidogrel daily) to 36 CRF patients (75 mg or 150 mg clopidogrel daily).
  • Assessed platelet responsiveness using the VerifyNow P2Y12 assay, measuring P2Y12 reaction units and percentage of inhibition.

Main Results:

  • Patients with CRF showed significantly reduced platelet responsiveness to clopidogrel compared to those with normal renal function (p=0.013 for P2Y12 reaction units, p=0.026 for percentage of inhibition).
  • Increasing clopidogrel dosage from 75 mg to 150 mg daily did not significantly improve platelet responsiveness in CRF patients.
  • No significant difference in P2Y12 reaction units or percentage of inhibition was observed between the 75 mg and 150 mg clopidogrel groups in CRF patients.

Conclusions:

  • Platelet responsiveness to clopidogrel is diminished in patients with chronic renal failure.
  • Higher clopidogrel doses do not effectively enhance platelet inhibition in CRF patients.
  • Current clopidogrel dosing strategies may be suboptimal for CRF patients, necessitating further research into alternative antiplatelet therapies.

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