Assess the predictive accuracy of the expanded NIH Stroke Scale (e-NIHSS) versus the NIH-Stroke-Scale (NIHSS) for poor outcomes in Hispanic patients with posterior circulation ischemic strokes (PCIS).

PCIS are challenging to diagnose and often lead to worse outcomes than anterior circulation strokes. Traditional scales like the NIHSS are primarily designed for anterior strokes, underestimating the severity of posterior strokes. This limitation is especially concerning for Hispanic populations, who are disproportionately affected and underrepresented in stroke research. The e-NIHSS includes additional assessments tailored to PCIS, improving outcome prediction and management.

A prospective analytical study was conducted at a Stroke Center in Ecuador from 2023 to 2024. Patients presenting with PCIS were included. Stroke severity was assessed using the NIHSS and e-NIHSS scores at admission. Functional disability was measured using the modified Rankin Scale (mRS) three months post-discharge. Poor outcomes were defined as mRS ≥3. Statistical analyses included ROC curve analysis, Area Under the Curve (AUC) comparison using the DeLong method, sensitivity/specificity evaluation, and likelihood ratios (LR).

A total of 122 patients were included (mean age 68±12 years; male: 66.4%). The e-NIHSS showed superior predictive performance compared to the NIHSS (AUC: 0.84, p<0.001, AUC: 0.78, p<0.001, respectively). The DeLong method revealed a statistically significant difference between the scales (p=0.032). At a cutoff of 7, the e-NIHSS had higher sensitivity (76.6%) but lower specificity (74.1%) than the NIHSS (sensitivity: 39.1%; specificity: 89.7%). The e-NIHSS positive LR was 2.96, indicating a threefold increase in the probability of poor outcomes, while the negative LR was 0.32, decreasing the likelihood of poor outcomes at lower scores.

The e-NIHSS offers improved sensitivity in predicting poor outcomes after posterior circulation stroke compared to the NIHSS among Hispanics. Its integration into clinical protocols could enhance risk stratification and guide early interventions to improve long-term patient outcomes.