[Aspirin response and related factors in aged patients].
OBJECTIVE
To explore clinical and laboratory factors associated aspirin response, and the association between gastrointestinal bleeding and aspirin response in aged patients.


METHODS
A total of 136 patients aged 60 and over [mean age (74.9 ± 7.0) years] with ischemic heart disease and at high risk for ischemic heart disease were included. Arachidonic acid induced platelet aggregation (AA-Ag) was measured before and at 7(th) day after taking aspirin (100 mg/d). Patients were followed for 6 months and incidence of gastrointestinal bleeding was obtained.


RESULTS
Post-treatment AA-Ag was significantly reduced compared to baseline (13.29% ± 5.52% vs. 73.20% ± 7.32%, P < 0.05). A heterogeneous distributed post-treatment AA-Ag was observed (range 0.42% to 30.50%). Post-treatment AA-Ag was positively correlated with baseline AA-Ag (r = 0.493, P < 0.01). The level of post-treatment AA-Ag was significantly higher in the fourth quartile group at baseline than in the others quartile groups at baseline. Patients aged 80 years and over had significantly lower post-treatment AA-Ag (10.25% ± 4.68%) compared with patients of 60 - 69 years (13.96% ± 5.20%) and of 70 - 79 years (13.73% ± 5.48%, all P < 0.01). The incidence of patients in the lowest quartile of post-treatment AA-Ag was significantly higher in patients ≥ 80 years (38.24%) than in patients of 60 - 69 years (11.1%) and of 70 - 79 years (24.0%). Multiple variable analysis revealed post-treatment AA-Ag was significantly influenced by baseline AA-Ag, ≥ 80 years old, diabetes mellitus and acute coronary syndrome. We observed 4 (2.9%) mild gastrointestinal bleeding during follow up. Post-treatment AA-Ag was in the lowest quartile in 3 patients with mild gastrointestinal bleeding.


CONCLUSIONS
Increased baseline platelet reactivity as well as diabetes mellitus and acute coronary syndrome are associated with low aspirin response in the aged patients. Aspirin response is significantly higher in very old patients.
Department of Geriatrics, Peking University First Hospital, Beijing 100034, China.
Xue-ru
XR
Feng
Mei-lin
ML
Liu
Fang
F
Liu
Qing-ping
QP
Tian
Yan
Y
Fan
Qian-zhu
QZ
Liu
D054058:Acute Coronary Syndrome; D000368:Aged; D000369:Aged, 80 and over; D016718:Arachidonic Acid; D001241:Aspirin / Q000009:adverse effects / Q000627:therapeutic use*; D003324:Coronary Artery Disease / Q000188:drug therapy; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced*; D006801:Humans; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000188:drug therapy; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D010979:Platelet Function Tests; D013988:Ticlopidine
D010975:Platelet Aggregation Inhibitors; D016718:Arachidonic Acid; D013988:Ticlopidine; D001241:Aspirin