152 Lessons and experiences in recruitment and retention challenges from the Alzheimer’s disease progression after stroke study (ADAPT-MRI)

Objectives/Goals: Stroke and Alzheimer’s disease (AD) often co-occur. The ADAPT-MRI study faced major enrollment challenges while assessing stroke’s impact on AD. This analysis examined recruitment and retention barriers in enrolling adults with early cognitive impairment and recent stroke for a longitudinal imaging study. Methods/Study Population: The ADAPT-MRI study is a prospective, observational study targeting 50 participants aged ≥50 with mild AD or mild cognitive impairment and recent acute ischemic stroke/transient ischemic attack (AIS/TIA). Participants underwent serial cognitive testing, advanced MRI, and blood sample collection over 12 months. Screening logs from 1,981 individuals obtained over a period of 2 years (2022–2024)were analyzed to assess eligibility, exclusions, and reasons for non-participation. Data included demographics, stroke type, and cognitive status. Descriptive statistics were used to quantify recruitment outcomes and retention rates, highlighting logistical, psychosocial, and protocol-related barriers. Results/Anticipated Results: Of 1,981 individuals screened, only 11 participants (22% of target) were enrolled. The most frequent exclusions were stroke outside the protocol time window (20%), unrelated diagnoses (19%), and hemorrhagic stroke (18%). Of the 46 individuals who met eligibility criteria, 16 consented, 5 were later classified as screen failures, and 11 were successfully enrolled. Declining participation was most often due to disinterest (57%), caregiver or patient overwhelm (18%), and travel or scheduling difficulties (14%). Retention declined over time, with 63.6% completing Visit 1 and only 45.5% completing all scheduled follow-up visits. Discussion/Significance of Impact: Recruitment was hindered by protocol rigidity, limited imaging access, and participant barriers. Future stroke-AD studies should use flexible criteria, decentralized imaging, and caregiver support, emphasizing pragmatic, participant-centered approaches.