Stroke Alarm Efficacy Trial

The aim of this study is to test the efficacy of the CE-marked wearable system Stroke Alarm to identify the onset of a stroke with unilateral arm motor deficit within 3 hours of onset.

This is a multicenter, prospective observational single-arm trial with a registry-based propensity matched control population.

A total of 500 patients will be included in the trial. An interim analysis will determine if the stroke onset frequency is sufficient to determine the main outcome. Should the number of stroke events differ from what is expected at interim analysis, study enrollment will continue to increase cohort size.

Patients who meet the criteria for participation will, after signing consent, be included and receive the Stroke Alarm bracelets that are used for 3 months. Study data will be collected as baseline at inclusion, at follow-up 3 months after inclusion and by using national Swedish registry data after completion of the study.

Patients with elevated stroke risk according assessed by presence of specific criteria associated with elevated risk caused by:

1. recent TIA with an ABCD2 score of ≥6, large artery atherosclerosis or atrial fibrillation, OR 2. recent ischemic stroke with large artery atherosclerosis or atrial fibrillation, without persisting arm motor deficit, OR 3. atrial fibrillation with an CHA2DS2-Vasc score ≥ 4 without adequate anticoagulation OR 4. recent hemorrhagic stroke with atrial fibrillation, without persisting arm motor deficit The combined efficacy goal is at least 60% sensitivity for Stroke Alarm b of stroke with unilateral arm motor deficit within 3 hours of onset (with a 95% confidence interval above 30%) and a specificity of at least 80% using a clinical stroke diagnosis as gold standard.

A control population matched for calendar year, age (± 5 years), sex, healthcare region, baseline stroke severity according to the National Institutes of Health Stroke Scale (NIHSS, ± 5 points), unilateral arm motor deficit (NIHSS item 5a/5b 1-4), presence of neglect/inattention (NIHSS item 11 1-2), atrial fibrillation, cohabitation status and pre-stroke functional level twill be identified in the Swedish national stroke registry, Riksstroke, and used for comparison.