Dual Antiplatelet Therapy highly Effective in Patients with Minor Stroke: JAMA

A recent research published in the Journal of American Medical Association suggests that dual antiplatelet therapy (DAPT) may be a highly effective treatment for minor acute ischemic stroke. The findings offer better hope for patients and provide critical insights into the comparative effectiveness of different DAPT regimens.

This comprehensive study compared the efficacy of DAPT specifically for minor strokes, excluding other similar conditions such as transient ischemic attacks (TIA). The research conducted a thorough review of randomized clinical trials up to November 4, 2023 which were sourced from PubMed. Search terms included TIA, transient ischemic attack, minor stroke and moderate stroke by filtering for randomized controlled trials. 

Utilizing an initial pool of 1508 studies in total, 6 trials (0.3%) met the stringent inclusion criteria. The study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and involved multiple observers to ensure accuracy and reliability. The study also employed a Bayesian fixed-effect network meta-analysis and a secondary analysis which were focused solely on high-risk TIA.

The study incorporated data from five trials, including 28,148 patients of whom 22,203 (78.9%) had a minor stroke. Within this big group, 13,995 (63.0%) received DAPT, while 8208 (37.0%) were treated with aspirin (acetylsalicylic acid) alone.

The primary outcome was the incidence of subsequent ischemic stroke within 90 days. This study found that the combination of aspirin and ticagrelor had a 94% probability of being the most effective treatment for preventing recurrent ischemic stroke (SUCRA, 0.94). The number needed to treat (NNT) to prevent one ischemic stroke was 40 for aspirin and ticagrelor, and 58 for aspirin and clopidogrel which indicated that both combinations were significantly more effective than aspirin alone.

Despite the effectiveness, DAPT treatments were linked with higher rates of major hemorrhage when compared to aspirin alone. The number needed to harm (NNH) for major hemorrhage was 284 for aspirin and ticagrelor and 330 for aspirin and clopidogrel. Also, neither regimen increased the risk of hemorrhagic stroke or death.

For patients with high-risk TIA, the analysis indicated that both aspirin and ticagrelor (SUCRA, 0.60) and aspirin and clopidogrel (SUCRA, 0.40) were superior to aspirin alone in preventing recurrent ischemic stroke, although neither combination was definitively optimal. Overall, the study suggests that DAPT when combined with aspirin and ticagrelor has a high probability of being the most effective treatment for minor stroke, especially in the absence of CYP2C19 loss-of-function alleles. 

Reference:

Lim, A., Ma, H., Ly, J., Singhal, S., Pan, Y., Wang, Y., Johnston, S. C., & Phan, T. G. (2024). Comparison of Dual Antiplatelet Therapies for Minor, Nondisabling, Acute Ischemic Stroke: A Bayesian Network Meta-Analysis. In JAMA Network Open (Vol. 7, Issue 5, p. e2411735). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2024.11735