Abstract WP311: In-Hospital Resolution of Post-Stroke Delirium Associated with Lower Early Readmission Rate

Introduction: Delirium Present on Admission (DPOA) in acute ischemic stroke is associated with prolonged hospital stays, greater healthcare utilization, and a higher 30-day readmission rate. However, the relative benefits of in-hospital DPOA resolution for early readmission remain unclear. Methods: Data for adult (>18 years) acute ischemic stroke patients with DPOA were extracted from a stroke outcomes registry for a 7-hospital stroke certified healthcare system, including patient characteristics and readmission. Comorbidity burden was graded by Charlson Comorbidity Index (CCI). Stroke severity was measured by National Institute of Health Stroke Scale (NIHSS), with moderate-severe stroke defined as NIHSS > 4. Delirium was assessed using the modified 4As Test (4AT); DPOA was defined as ≥1 positive 4AT within 48 hours of admission, while resolution was defined by consistent negative 4ATs after DPOA. Delirium Burden Index (DBI; (Positive 4AT 2 /Total 4AT)) was used to measure overall dose of delirium. Descriptive statistics are provided as proportions (%) and medians with interquartile ranges (IQR). Demographic and comorbidity differences were assessed using chi-squared and Mann-Whitney U tests. A Cox proportional hazards model evaluated the association between in-hospital resolution of DPOA and readmission rate, adjusting for age, sex, ethnicity, stroke severity, CCI, DBI, and discharge home (vs. non-home discharge). Event times were censored at 30 days for patients not readmitted. Results: A total of 4842 patients were included, with median age of 79 years (IQR: 72-86); 57.9% were female and 14.5% were Hispanic. DPOA was resolved in 1,729 patients (35.7 %), and a total of 518 (10.7%) readmitted within 30 days of discharge. Patients with resolved DPOA (vs. unresolved DPOA) were younger (median 77 vs. 80 years), had lower Charlson Comorbidity Index scores, and were more frequently discharged home (53.5 % vs. 27.4 %) (Table 1). The 30-day readmission rate was lower in the resolved group (8.9 % vs. 11.7 %). In-hospital resolution of DPOA was independently associated with a reduced hazard of 30-day readmission (HR 0.78; 95 % CI, 0.63–0.96). Conclusion: In-hospital resolution of DPOA in ischemic stroke was associated with a 22 % lower hazard of 30-day readmission, independent of age, sex, ethnicity, DBI, stroke severity and discharge disposition. These highlight the potential value of early delirium recognition and management for reducing early rehospitalizations.