title: [Clopidogrel resistance of patients with coronary artery disease and its correlation with platelet count and mean platelet volume].
abstract: OBJECTIVE
  To explore the association between clopidogrel resistance (CR) as assessed by whole blood electrical impedance aggregometry (EIA) and platelet parameters.
  
  
  METHODS
  The prospective study comprised 152 patients with coronary artery disease (CAD) on the therapy of clopidogrel. EIA employed adenosine diphosphate (ADP) as an inductor to measure platelet aggregation. CR was defined by spontaneous aggregation (electrical impedance ≥ 10 Ω). The subjects were divided into 2 groups of CR and clopidogrel sensitive (CS). Platelet parameters were measured by routine blood test. And their clinical data and outcomes were analyzed.
  
  
  RESULTS
  The prevalence of CR was 10.5% (n = 16). The ratio of patients with diabetes in CR group was higher than that in CS group (7/16 vs 29/136, P = 0.046). Platelet counts and mean platelet volume (MPV) were also higher in CR group than those in CS group ((241 ± 58) ×10(9)/L vs (185 ± 56)×10(9)/L, (8.0 ± 0.8) fl vs (7.4 ± 0.9) fl, both P < 0.05). Logistic regression indicated each 10×10(9)/L increase in platelet and each 1 fl increase in MVP were associated with 0.376 and 1.015 folds increase in CR onset respectively (OR = 1.376, 95%CI 1.097 - 1.725, P = 0.006;OR = 2.015, 95%CI 1.148 - 3.537, P = 0.015). The patients with CR had more cardiovascular events during an average follow-up of 53 months (6/16 vs 23/136, P = 0.047).
  
  
  CONCLUSIONS
  CAD patients with CR had higher incidence of cardiovascular events. Increased platelet counts and MPV levels are independent predictors for CR in CAD patients.
authors.affiliation: Department of Cardiology, Peking University Third Hospital, Beijing, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Jiang-li
authors.initials: JL
authors.lastname: Han
authors.forename: Hai-yan
authors.initials: HY
authors.lastname: Li
authors.forename: Rui
authors.initials: R
authors.lastname: Qiao
authors.forename: Hai-yi
authors.initials: HY
authors.lastname: Yu
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Gao
mesh_terms: D000368:Aged; D000077144:Clopidogrel; D003324:Coronary Artery Disease / Q000097:blood* / Q000188:drug therapy; D004351:Drug Resistance; D005260:Female; D006801:Humans; D008297:Male; D063847:Mean Platelet Volume; D008875:Middle Aged; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D010976:Platelet Count; D011446:Prospective Studies; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine