The 6-months follow-up of the TREAT-CAD trial: Aspirin versus anticoagulation for stroke prevention in patients with cervical artery dissection

Introduction Cervical artery dissection is a major cause of stroke in the young. The optimal choice and duration of antithrombotic treatment for stroke prevention are debated, particularly beyond 3 months after symptom onset. Patients and methods TREAT-CAD (TREATment of Cervical Artery Dissection) was a randomized controlled trial with blinded outcome assessment comparing non-inferiority of aspirin to anticoagulation (Vitamin-K-antagonists) in participants with symptomatic, Magnetic-Resonance-(MR)-imaging-verified cervical artery dissection. TREAT-CAD could not establish non-inferiority of aspirin to anticoagulation at 3 months. Thereafter participants could continue antithrombotic medication and obtained a standardized assessment of clinical and MR-Imaging outcomes between 3 and 6 months. As crossover to the other treatment arm was possible, we performed an as-treated analysis as main analysis. The main outcomes were new clinical (ischemic stroke, intracranial/major extracranial bleeding, or death) and new MR-Imaging outcomes (ischemic or hemorrhagic brain lesions). Results Among the 122 participants in the as-treated analysis, 3/93 (3.2%) aspirin-treated participants had new clinical (n = 1) and MRI-outcomes (n = 2) between 3 and 6 months while 1/29 (3.4%) anticoagulated participants had an MRI-outcome (n = 1). All outcome events were hemorrhagic while ischemic events were absent. No deaths occurred. This yields an absolute difference of 0.2% (95% CI −8.0% to 7.5%, p = 1.0). Discussion and conclusion During the extended follow-up period of a controlled randomized trial comparing aspirin to anticoagulation in cervical artery dissection, outcomes between 3 and 6 months after randomization occurred rarely, similarly often in both groups and were exclusively hemorrhagic events. Thus, studies balancing benefits versus harms of antithrombotic treatment beyond 3 months are warranted. Registration: ClinicalTrials.gov: NCT02046460. https://clinicaltrials.gov/ct2/show/NCT02046460.