Agitation in acquired brain injury: Impact on acute rehabilitation therapies

Objective: To examine the nature of agitation in patients with brain injury and quantify the relation between agitation and patient progress in rehabilitation. Design: Cross-sectional, correlational. Setting: Urban, inpatient rehabilitation facility in the midwestern United States. Participants: Sixty-nine patients with acquired brain injury admitted to an acute rehabilitation hospital. Main Outcome Measures: Therapy Engagement using the Rehabilitation Therapy Engagement Scale; Functional Status using the Functional Independence Measure. Results: Agitated behavior was inversely associated with engagement in rehabilitation therapy even after controlling for injury severity. Engagement in therapy mediated the relation between agitated behavior and progress in rehabilitation as assessed using a Functional Independence Measure efficiency ratio. Conclusions: Progress in acute brain injury rehabilitation appears to be meaningfully influenced by the complex interplay among injury severity, agitation, and engagement. The findings are consistent with a theoretical model, suggesting that agitated patients make less progress in rehabilitation not only because of greater injury severity but also because agitation disrupts engagement in rehabilitation therapies. Multiple clinical purposes may be better served by measuring behavioral excess on a continuum than in a dichotomous fashion.