Article Text

Download PDFPDF
Impact of clopidogrel loading dose on clinical outcome in patients undergoing percutaneous coronary intervention: a systematic review and meta-analysis
  1. Jolanta M Siller-Matula1,
  2. Kurt Huber2,
  3. Günter Christ3,
  4. Karsten Schrör4,
  5. Jacek Kubica5,
  6. Harald Herkner6,
  7. Bernd Jilma1
  1. 1Department of Clinical Pharmacology, Medical University of Vienna, Austria
  2. 23rd Medical Department, Cardiology and Emergency Medicine, Wilhelminenhospital, Vienna, Austria
  3. 35th Medical Department, Kaiser-Franz-Joseph Hospital, Vienna, Austria
  4. 4Department of Pharmacology and Clinical Pharmacology, Heinrich-Heine-University, Düsseldorf, Germany
  5. 5Department of Cardiology, Nicolaus Copernicus University, Torun, Poland
  6. 6Department of Emergency Medicine, Medical University of Vienna, Austria
  1. Correspondence to Dr Bernd Jilma, Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18–20, A-1090 Vienna, Austria; bernd.jilma{at}


Context Enhanced platelet inhibition by clopidogrel decreases the risk of ischemic events but carries a risk for a concomitant increase in bleeding.

Objectives To compare the efficacy and safety of two clopidogrel loading regimens (300mg vs. 600mg) in patients undergoing percutaneous coronary intervention (PCI) at one month after start of therapy.

Data sources A systematic literature search of MEDLINE, EMBASE, CENTRAL, and Web of Science databases using predefined search terms for relevant articles in any language.

Study selection and data extraction Randomised controlled trials and non-randomised studies reporting adjusted effect estimates were included. Summary estimates of the risks ratios (RRs) with therapy were calculated using a random-effect model. Outcomes evaluated were combined major adverse cardiovascular events (MACE) and major bleedings.

Results Seven studies met the inclusion criteria and included 25,383 patients. A 600mg clopidogrel loading was associated with a 34% relative risk reduction of MACE (RR=0.66; 95% confidence intervals CI=0.52-0.84; p<0.001). Sub-analysis revealed a 47% risk reduction of MACE in randomised trials (RR=0.53; 95%CI=0.32-0.88; p=0.01) and a 31% relative risk reduction in non-randomised trials (RR=0.69; 95%CI=0.54-0.90; p=0.005) in patients receiving 600mg loading with clopidogrel. In patients suffering from acute coronary syndrome, 600mg clopidogrel loading was associated with a 24% relative risk reduction in MACE (RR=0.76; 95%CI=0.60-0.95; p=0.02). Importantly, the 600mg clopidogrel loading dose was not associated with an increased risk of major bleedings (RR=0.91; 95%CI=0.73-1.15; p=0.44).

Conclusions This meta-analysis demonstrates that intensified clopidogrel loading with 600mg reduces the rate of major cardiovascular events without increase in major bleeding compared to 300mg in patients undergoing PCI during one month follow-up.

  • Clopidogrel
  • loading dose
  • MACE
  • bleeding
  • PCI
  • platelets
  • coronary intervention
  • coronary artery disease (CAD)
  • pharmacokinetics/phramacodynamics
  • epidemiology

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • See Paper, p 106

  • Competing interests None.

  • Patient consent Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

Linked Articles