title: Comparison of platelet reactivity and clopidogrel response in patients ≤ 75 Years Versus > 75 years undergoing percutaneous coronary intervention for non-ST-segment elevation acute coronary syndrome.
abstract: Specific data about the clopidogrel response in elderly patients are lacking. The present study was performed to compare the platelet reactivity and clopidogrel response between patients aged > 75 years and < 75 years undergoing percutaneous coronary intervention for non-ST-segment elevation acute coronary syndrome. A total of 689 patients were enrolled, including 162 patients aged > 75 years and 527 younger patients. All patients received a loading dose of 600 mg clopidogrel followed by 150 mg/day. Post-treatment platelet reactivity was assessed by adenosine diphosphate 10 μmol/L-induced platelet aggregation and the specific pharmacologic response to clopidogrel by the platelet reactivity index vasoactive stimulated phosphoprotein. High post-treatment platelet reactivity was defined as adenosine diphosphate 10 μmol/L-induced platelet aggregation >70%. Clinical events were recorded during 1 month of follow-up. The patients > 75 years old had a greater rate of both ischemic and bleeding complications (p = 0.04 and p = 0.03, respectively). The post-treatment platelet reactivity in response to both the loading and the maintenance clopidogrel dose was greater in patients > 75 years old than in the younger patients: 50 ± 17% versus 45 ± 17% (p = 0.002) and 57 ± 15% versus 53 ± 16% (p = 0.0005), respectively. The rate of high post-treatment platelet reactivity was significantly greater in patients aged > 75 years after 600 mg and 150 mg clopidogrel: 14% versus 9% (p = 0.04) and 23% versus 15% (p = 0.02), respectively. In contrast, the pharmacologic response to clopidogrel was not impaired in patients > 75 years after loading and maintenance doses: 43 ± 21% versus 46 ± 21% (p = 0.17) and 38 ± 18% versus 39 ± 18% (p = 0.55), respectively. In conclusion, patients aged > 75 years have an impaired prognosis after acute coronary syndrome. They display greater post-treatment platelet reactivity. However, this greater platelet reactivity does not seem to be related to an impaired specific response to clopidogrel.
authors.affiliation: Département de Cardiologie, CHU Timone, Marseille, France. thomascuisset@voila.fr
authors.forename: Thomas
authors.initials: T
authors.lastname: Cuisset
authors.forename: Jacques
authors.initials: J
authors.lastname: Quilici
authors.forename: Charlotte
authors.initials: C
authors.lastname: Grosdidier
authors.forename: Laurent
authors.initials: L
authors.lastname: Fourcade
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Gaborit
authors.forename: Mathieu
authors.initials: M
authors.lastname: Pankert
authors.forename: Laurent
authors.initials: L
authors.lastname: Molines
authors.forename: Pierre-Emmanuel
authors.initials: PE
authors.lastname: Morange
authors.forename: Jean Louis
authors.initials: JL
authors.lastname: Bonnet
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Alessi
mesh_terms: D054058:Acute Coronary Syndrome / Q000453:epidemiology / Q000628:therapy*; D000244:Adenosine Diphosphate; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary; D001241:Aspirin / Q000008:administration & dosage; D000077144:Clopidogrel; D004351:Drug Resistance; D005500:Follow-Up Studies; D006470:Hemorrhage / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000453:epidemiology; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D011446:Prospective Studies; D012008:Recurrence; D015607:Stents; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*
chemical_list: D010975:Platelet Aggregation Inhibitors; D000244:Adenosine Diphosphate; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin