ABSTRACT NUMBER: ESOC2026A467 ADVANCE CONSENT FOR PARTICIPATION IN ACUTE STROKE TRIALS: QUANTITATIVE RESULTS FROM A FEASIBILITY STUDY

Abstract Background and aims Obtaining informed consent is challenging for acute stroke trials. We sought to assess the feasibility of a novel approach: advance consent, in which a person at risk of stroke provides consent to a trial in advance of experiencing an acute stroke. Methods Patients assessed in the Stroke Prevention Clinic at The Ottawa Hospital (Ottawa, Canada) were screened for diagnoses associated with a risk of acute stroke. Eligible patients completed an initial questionnaire and a follow-up questionnaire at 1 year. Participants who responded favourably to the idea of advance consent were invited to provide informed consent for 2 active acute stroke trials. Participants were followed for 1 year with regards to subsequent acute stroke and trial enrollment. Results From July 2023 to July 2024, we screened 1,547 patients; 431 met eligibility criteria, and 157 completed the initial questionnaire. Respondents overwhelmingly approved of advance consent in the initial questionnaire (96%) and at follow-up (92%). Based on their responses, 110 respondents were invited to provide advance consent; 48 participants (43%) did so, with 1 person withdrawing consent. Only 3 participants (2%) experienced any stroke, with none in the advance consent group, and no participants were enrolled into an acute stroke trial. Conclusions In this feasibility study, advance consent was strongly endorsed by participants, though ultimately this did not translate into improved trial enrollment. Conflict of interest Michel Shamy: Nothing to disclose; Ubong Udoh: Nothing to disclose; Brian Dewar: Nothing to disclose; Dar Dowlatshahi: Nothing to disclose