Balancing Rehabilitation Dose in Acute Stroke Decision-Making and Global Assessment (The BRIDGE Study)

<b>Background/Objectives:</b> Stroke remains a leading cause of disability in Japan, and early mobilization is an important strategy to prevent muscle atrophy and promote independence. However, the optimal intensity and duration of early rehabilitation remain unclear. This study aims to examine the association between rehabilitation dose during the acute phase of stroke and functional outcomes at 90 days post-onset. <b>Methods:</b> This multicenter prospective cohort study will enroll patients from twelve acute care hospitals across Japan, beginning in June 2026. Eligible patients are aged ≥ 18 years, expected to be hospitalized for ≥7 days, and initiated rehabilitation by day 2 after stroke onset. Rehabilitation dose will be quantified using the Mobilization Quantification Score (MQS). The primary outcome is functional status measured by the modified Rankin Scale (mRS) at 90 days. Secondary outcomes include muscle atrophy assessed by ultrasound, the Barthel Index, and physical performance measures. Subgroup analyses will evaluate how stroke severity modifies the dose-response relationship. <b>Results:</b> As this is a study protocol, results are not yet available. The study is designed to clarify the relationship between early rehabilitation dose and functional recovery after stroke. <b>Conclusions:</b> This is the first large-scale Japanese study to assess early stroke rehabilitation dosage using a standardized tool. Findings are expected to provide evidence for individualized, evidence-based mobilization strategies to optimize functional outcomes in stroke patients.