To determine if there is a significant correlation between the Ischemic Stroke In-Hospital Mortality Score (ISIHMS) and stroke hospital discharge disposition in a sample of acute ischemic stroke (AIS) patients at an academic, Comprehensive Stroke Center (CSC). We also examined correlation of ISIHMS with discharge modified Rankin Scale (mRS) and hospital length of stay (LOS).

The ISIHMS is a score used to predict in-hospital mortality from AIS based on patient characteristics available at hospital admission including demographics, comorbidities, mode of presentation, and timing of admission. Higher ISIHMS has been shown to predict higher risk of in-hospital mortality. The ISIHMS is strongly associated with initial National Institutes of Health Stroke Scale (NIHSS), but ISIHMS has not been studied in its association with discharge disposition, discharge mRS, and LOS during AIS hospitalization.

We retrospectively examined prospectively collected data from an IRB-approved stroke registry at two academic CSCs. AIS patients were included if they presented between 1/1/2013 to 6/30/2022. Discharge disposition was grouped into: Home, Inpatient Rehabilitation Facility (IRF), Skilled Nursing Facility (SNF), Long-term Care Hospital (LTCH), Hospice, or Death. Patients discharged Against Medical Advice were excluded. Correlations were assessed via Spearman’s or Pearson Correlation Coefficient as appropriate.  A p-value of <0.05 was considered significant.

A total of 1752 patients met study criteria. Of these, 32.4% (n=567/1752) had discharge mRS collected. The frequency of discharge disposition was: Home 62.8%, IRF 8.2%, SNF 21.7%, LTCH 0.7%, Hospice 3.9%, and Death 2.6%. The ISIHMS was significantly correlated with discharge disposition (r_s=0.474, p<0.001), discharge mRS (r_s=0.475, p<0.001), and hospital LOS (r_p=0.214, p<0.001).

The ISIHMS was significantly correlated with discharge disposition, discharge mRS, and hospital LOS. ISIHMS can potentially inform hospital discharge decisions and quality analyses, but further studies are needed to validate the ISIHMS for predicting hospital disposition.