We aimed to validate existing stroke scales for inpatient stroke codes and secondarily sought to develop a novel score to predict stroke in the inpatient setting.

A significant proportion of strokes occur while patients are hospitalized for other reasons. Numerous stroke scales have been developed and validated for use in pre-hospital and emergency department settings, and there is growing interest to adapt these scales for the inpatient setting.

We retrospectively reviewed charts from inpatient stroke code activations at an urban academic medical center from January 2016 through December 2018. The following variables were collected: baseline patient demographics, vascular risk factors, seizure history, baseline modified Rankin scale (mRS) score, National Institutes of Health Stroke Scale (NIHSS) score, laboratory values, presence of cardiac procedure during the current admission, and final diagnosis as determined by an attending vascular neurologist. We used logistic regression to identify independent predictors of stroke. Receiver operating characteristics analysis was performed for each specified stroke scale including NIHSS, FAST, BE-FAST, FABS, Tele-Stroke Mimic, and LAPSS.

Of the 958 stroke code activations reviewed, 151 (15.8%) had a final diagnosis of cerebrovascular event and 807 (84.2%) were diagnosed as stroke mimics. Four risk factors independently predicted cerebrovascular events: (1) recent cardiovascular procedure, (2) platelet count less than 50 x 10⁹ per liter, (3) gaze deviation, and (4) presence of unilateral leg weakness. Combining these 4 factors into a new score yields an area under the curve (AUC) of 0.653 (95% confidence interval [CI] 0.604-0.702). The AUC of existing scales varied from 0.465 (FABS score) to 0.563 (2CAN score).

This study suggests that presently available stroke scales may not be sufficient to differentiate strokes from mimics in the inpatient setting. Though we created a new score for use in hospitalized patients, there is a need for further development of inpatient stroke scales.