Secondary Prevention Gaps at Recurrent Ischemic Stroke Admission: A Nationwide Registry Study

Background and Purpose Recurrent ischemic stroke is a sentinel audit point for secondary prevention delivery. We quantified attainment of prevention indicators, sex- and age-related heterogeneity, and projected prevention gains.Methods We analyzed 24,183 recurrent ischemic stroke admissions from 81 Korean Stroke Registry hospitals (2018–2023). Annual attainment of antithrombotic therapy, low-density lipoprotein cholesterol (LDL-C) <70 mg/dL, glycated hemoglobin (HbA1c) <7.0% in diabetes, non-current smoking, and normal weight (body mass index [BMI] 18.5–24.9 kg/m²) was age-standardized descriptively; temporal trends were assessed with hospital-clustered generalized estimating equation models. Projections combined observed implementation gaps with trial-derived relative risk reductions.Results Antithrombotic use increased from 74.6% to 79.4% (odds ratio [OR]/year 1.05, 95% confidence interval 1.01–1.09), but plateaued after 2019, leaving 20.6% untreated in 2023. Among 4,441 patients with known atrial fibrillation (AF), oral anticoagulant use rose from 65.3% to 73.3% (OR/year 1.08; P=0.005), and 26.7% remained untreated. LDL-C <70 mg/dL improved from 32.6% to 41.9% (OR/year 1.08; P<0.001), whereas HbA1c, smoking, and weight indicators showed limited overall progress. Heterogeneity emerged: non-current smoking improved in men but not women (already near ceiling, approximately 95%); LDL-C control did not improve in adults aged 19–49 years; and BMI ≥25 kg/m² rose from 36.2% to 56.2% in this age group. Upper-bound projections estimated approximately 183, 126, and 201 potentially preventable recurrent strokes per year within the registry (not national estimates) from antithrombotic non-use, anticoagulant non-use in AF, and LDL-C gaps in large-artery atherosclerosis, respectively.Conclusions Recurrent-stroke admission revealed persistent, unevenly distributed prevention gaps. Medication reconciliation, AF detection and anticoagulation, lipid intensification, and tailored behavioral pathways should be prioritized.