title: Effect of proton pump inhibitors on platelet inhibition activity of clopidogrel in Chinese patients with percutaneous coronary intervention.
abstract: BACKGROUND
  The purpose of this study was to examine the effect of proton pump inhibitors (PPI) on the antiplatelet activity of clopidogrel in a consecutive series of Chinese patients after they had received coronary stents.
  
  
  METHODS
  A sample of 51 consecutive Chinese patients treated with coronary stents and taking PPI and clopidogrel for more than 30 days were enrolled in this study. Mean values for platelet residual units and percentage inhibition before PPI (+PPI) and 14 days after discontinuation of PPI (-PPI) were compared using the paired t-test.
  
  
  RESULTS
  There was no effect of concomitant use of esomeprazole and clopidogrel or omeprazole and clopidogrel on the inhibition assay, but platelet residual units and percentage inhibition showed statistically significant improvement after stopping lansoprazole in Chinese patients who were on chronic clopidogrel therapy. Clopidogrel resistance existed more frequently in the Chinese-American population examined, and was as high as 68% (+PPI) to 73% (-PPI).
  
  
  CONCLUSIONS
  The clopidogrel resistance found is cause for concern, although its relationship with clinical events is currently unknown in this population. Further study with other thienopyridines or genetic variant analysis is suggested.
authors.affiliation: Boston University, Boston, MA, USA.
authors.forename: Joanne
authors.initials: J
authors.lastname: Kwan
authors.forename: Wah Wah
authors.initials: WW
authors.lastname: Htun
authors.forename: Yili
authors.initials: Y
authors.lastname: Huang
authors.forename: Wilson
authors.initials: W
authors.lastname: Ko
authors.forename: Tak W
authors.initials: TW
authors.lastname: Kwan
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000627:therapeutic use*; D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation; D001213:Asian; D044466:Asian People; D001792:Blood Platelets / Q000187:drug effects; D002681:China / Q000208:ethnology; D000077144:Clopidogrel; D004351:Drug Resistance; D064098:Esomeprazole; D005260:Female; D006801:Humans; D064747:Lansoprazole; D008297:Male; D008875:Middle Aged; D009519:New York City / Q000453:epidemiology; D009853:Omeprazole / Q000627:therapeutic use*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D010979:Platelet Function Tests; D011446:Prospective Studies; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D015607:Stents; D013927:Thrombosis / Q000097:blood / Q000208:ethnology / Q000517:prevention & control*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D010975:Platelet Aggregation Inhibitors; D054328:Proton Pump Inhibitors; D064747:Lansoprazole; D000077144:Clopidogrel; D009853:Omeprazole; D064098:Esomeprazole; D013988:Ticlopidine