Effect of a regional guideline-education initiative on dual antiplatelet therapy use in minor non-cardioembolic stroke: a pre–post analysis from the Shanghai Stroke Service System

Background Dual antiplatelet therapy (DAPT) reduces recurrent stroke in patients with minor non-cardioembolic ischaemic stroke or high-risk transient ischaemic attack (TIA). However, real-world prescribing remains heterogeneous. The Shanghai Stroke Service System (4S) initiated a guideline-focused education and audit-feedback programme aimed at improving standard DAPT use for minor strokes since 2019. This study evaluates its impact on the adherence to DAPT and clinical outcomes before and after this initiative. Methods This retrospective study used data from the 4S registry. Consecutive adult patients with acute minor ischaemic stroke (National Institutes of Health Stroke Scale≤3) or high-risk TIA (ABCD 2 score ≥4) between 2015 and 2021 were enrolled. Patients with suspected cardioembolism or who received intravenous thrombolysis were excluded. Standard DAPT was defined as aspirin plus clopidogrel initiated within 24 hours. Education throughout the 4S on the use of DAPT was carried out during 2018–2019. Outcomes during postimplementation period (2019–2021) were compared with preimplementation period (2015–2018). The primary outcome was standard DAPT rate; secondary outcomes included in-hospital stroke recurrence and non-standard DAPT. Results Among 58 491 patients, standard DAPT increased by 13.6% (95% CI 12.8 to 14.4; p<0.001) following 4S initiative. In-hospital stroke recurrence rate decreased by about 1% (aOR=0.91, 95% CI 0.85 to 0.98; p=0.01), driven primarily by improvements in tertiary hospitals. Paradoxically, non-standard DAPT also increased by 10.0% (95% CI 9.3 to 10.7; p<0.001). Interpretation Following implementation of a regional guideline-education initiative within 4S, standard DAPT use increased and overall in-hospital stroke recurrence declined. However, the parallel rise in non-standard DAPT use observed in secondary hospitals highlights persistent practice variability and the need for targeted quality-improvement strategies. Trial registration number NCT02735226 .