Aspirin Vital in Stroke Intervention

Researchers have determined that aspirin is the key to reducing the risk of an early recurrent stroke following a minor stroke or transient ischemic attack (TIA). The study, conducted by Professor Peter Rothwell, FMedSci, of the Stroke Prevention Research Unit, Nuffield Department of Clinical Neurosciences at the University of Oxford in the UK, and colleagues, was published in the Lancet on May 18, 2016.

The researchers began with the hypothesis that the short-term benefits of aspirin immediately following a minor stroke or TIA have been underestimated. In order to find out, they said, “We pooled individual patient data from all randomized trials of aspirin versus control in secondary prevention after TIA or ischemic stroke, we studied the effects of aspirin on the risk and severity of recurrent stroke, stratified by the following time periods: less than 6 weeks, 6-12 weeks, and more than 12 weeks after randomization.”

In total, the researcher pooled data from 15,778 participants in 12 trials. They report finding “aspirin reduced the 6 week risk of recurrent stroke by about 60%.” Further, the risk of disabling or fatal stroke was reduced by about 70%. However, there was no benefit after 12 weeks.

“Our analyses of trials of aspirin in secondary prevention after TIA and ischemic stroke show that the effect of aspirin on early recurrent events has been underestimated,” the researcher say. They add that “a major part of the early benefit of aspirin was due to an hitherto unrecognized reduction in severity of early recurrent ischemic stroke, resulting in up to a 90% reduction in early risk of disabling or fatal recurrent ischemic stroke after TIA and minor stroke.”

The researchers suggest several implications of this study. The results support recommendations for urgent assessment of patients, and the researchers say, the results “suggest that most of the benefit of urgent treatment in these previous multi-intervention studies was simply due to aspirin.” Patients in the emergency room should not be given a prescription, but rather, aspirin should be administered immediately. In cases where patients call advice lines or doctors’ offices and TIA is suspected, they should be instructed to take aspirin, and paramedics should administer aspirin when appropriate. The researchers futher suggest a public education program would be appropriate.

The authors conclude, “The previously unrecognized reduction in severity of early recurrent ischemic stroke by aspirin has important implications for clinical guidelines, interpretation of previous and future trials, and for understanding mechanism of action.”