title: [Clinical application of VerifyNow-P2Y12 assay in evaluation of platelet inhibition efficacy of clopidogrel].
abstract: OBJECTIVE
  To evaluate the platelet inhibition efficacy in patients under regular maintenance dose of clopidogrel by VerifyNow-P2Y12 assay and explore the clinical characteristics of clopidogrel non-responders and related predicting factors.
  
  
  METHODS
  A total of 99 patients underwent percutaneous coronary intervention procedure and receiving clopidogrel in regular maintenance dose for at least 1 week were enrolled. Platelet reactivity, including baseline, P2Y12 reaction unit (PRU), and platelet inhibition rate were measured with VeifyNow-P2Y12 assay. The dosage of anti-platelet drugs, combination with any other drugs, clinical characters in baseline of all enrolled patients were analyzed. PRU ≤ 240 was used as cut-off to identify clopidogrel responder and clopidogrel non-responder. In the non-responder group, patients were further separated into 3 sub-groups (types) according to the baseline and platelet inhibition rate: type I with high baseline, high inhibition rate, representing false non-responder; type II with low inhibition rate, representing true non-responder and type III mixed type.
  
  
  RESULTS
  In this study, 48 of 99 patients were found to be clopidogrel non-responder (48.5%). The ratio of type I, type II and type III in the non-responder group was 9.1% (n = 9), 27.3% (n = 27), and 12.1% (n = 12), respectively. Baseline platelet value in female patients was significantly higher than in males (P < 0.01), number of females with high PRU also is higher than males (P < 0.01), female gender was a predict factor for type I non-responder (OR = 6.5, 95%CI 2.295 - 18.407, P < 0.01). BMI > 24 kg/m(2) was a risk factor for clopidogrel non-responder (P < 0.05), and may be regarded as a predict factor for type II non-responder (OR = 3.207, 95%CI 1.375 - 7.485, P < 0.01). Age, hypertension, diabetics, smoking, hyperlipidemia, CRP and pantoprazole use do not show significant correlation with baseline and platelet inhibition rate.
  
  
  CONCLUSIONS
  Clopidogrel responses could be reliably detected by VerifyNow-P2Y12 assay. Female gender and high body weight are independent risk factors for clopidogrel non-responses.
authors.affiliation: Cardiovascular Center, Ningbo First Hospital, Ningbo, China.
authors.forename: Shao-yi
authors.initials: SY
authors.lastname: Lin
authors.forename: Han-bin
authors.initials: HB
authors.lastname: Cui
authors.forename: Xiao-min
authors.initials: XM
authors.lastname: Chen
authors.forename: Sheng-huang
authors.initials: SH
authors.lastname: Wang
authors.forename: Hong-lin
authors.initials: HL
authors.lastname: Zhou
authors.forename: Wei-ping
authors.initials: WP
authors.lastname: DU
authors.forename: Hong-hua
authors.initials: HH
authors.lastname: Ye
authors.forename: Wei-min
authors.initials: WM
authors.lastname: Pan
authors.forename: Rui
authors.initials: R
authors.lastname: Yang
authors.forename: Ming-jun
authors.initials: MJ
authors.lastname: Feng
authors.forename: Ye-wen
authors.initials: YW
authors.lastname: Hu
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Shi-qi
authors.initials: SQ
authors.lastname: Wang
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D000077144:Clopidogrel; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D010979:Platelet Function Tests; D058925:Receptors, Purinergic P2Y12; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D010975:Platelet Aggregation Inhibitors; D058925:Receptors, Purinergic P2Y12; D000077144:Clopidogrel; D013988:Ticlopidine