Background: Oral antiplatelet therapy is the cornerstone of treatment for acute myocardial infaction (AMI). However, detailed usage data on oral antiplatelet therapy are lacking.
Methods: Using data from a nationally representative sample of patients with AMI, the detailed usage of oral antiplatelet therapy was analyzed in 40,202 consecutive eligible patients.
Results: The proportions of patients with AMI taking loading doses of aspirin and P2Y12 inhibitors were relatively low (62.2% and 63.6%, respectively), whereas approximately 90% of patients received maintenance doses of aspirin, P2Y12 inhibitors, and dual antiplatelet therapy. The proportions of patients taking loading doses of aspirin and P2Y12 inhibitors gradually decreased with age. Male sex, an educational level of at least college, an interval from onset to treatment of < 24 h, and primary PCI use were associated with a higher proportion of patients taking a loading dose of antiplatelet therapy, whereas those receiving conservative treatment had a lower rate of antiplatelet use (all P < 0.05). The proportion of patients taking loading doses of aspirin was highest in the western region, and that of patients taking loading doses of P2Y12 inhibitors was highest in the eastern region (P < 0.05). In addition, 76.7% of patients with ST-elevation MI and 91% of patients with non-ST-elevation MI received 300-mg loading dose of clopidogrel.
Conclusions: The proportion of patients with AMI receiving loading doses of aspirin and P2Y12 inhibitors during hospitalization was relatively low, and this rate was affected by many factors, such as age, sex, educational level, region of residence, and the interval from onset to treatment. The underutilization of guideline-based P2Y12 inhibitors was also problematic. Hence, quality improvement initiatives are needed to enhance adherence to guidelines to improve consistent use of oral antiplatelet therapy. Trial registration The Chinese Acute Myocardial Infarction Registry; Trial registration number: ChiCTR-ONC-12002636; Registered 31 October 2012; http://www.chictr.org.cn/showproj.aspx?proj=6916.
Keywords: Acute myocardial infarction; Aspirin; Oral antiplatelet therapy; P2Y12 inhibitors.