Neuropsychological Predictors Of Engagement In Rehabilitation Therapy And Functional Independence In Individuals With Acquired Brain Injuries

Occupational therapy after acquired brain injury (ABI) is an important part of a rehabilitation program, as it is designed to assess and aid patients in regaining independent functioning with activities of daily living (ADL; eating, toileting, etc.) and instrumental ADL (IADL). Engagement in therapy is a patient factor that can limit or enhance the benefits of occupational therapy. Therapy engagement refers to deliberate effort and commitment to working toward the goals of rehabilitation (Lequerica et al., 2006); it encompasses patient participation in rehabilitation activities, such as attendance and completion of prescribed exercises. Low engagement and failure to maximize therapy are associated with increased health costs and disability (Barello et al., 2012). Brain injury can disrupt cognition and emotions, resulting in apathy and low engagement (Lane-Brown & Tate, 2011). Unfortunately, few studies have examined the link between cognitive impairments and engagement in therapy; fewer still have examined this link with endpoints of functional outcome. An important gap in the knowledge base concerns how cognitive impairments associated with ABI disrupt engagement in therapy, and the extent to which this disruption undermines the benefits of rehabilitation therapy. Accordingly, this dissertation study examined neuropsychological predictors of functional outcomes after ABI, and the role of therapy engagement as a potential mediator for the relationship between neuropsychological performance and functional outcomes. Method: Participants were 94 adults with medically-documented ABI recruited from three outpatient brain injury clinics at the beginning of occupational therapy. The participants (57% men) ranged from 18 to 82 in age with the majority (81%) having completed 12 or more years of education. Participants completed a comprehensive neuropsychological assessment at baseline. It included self-report surveys of emotional functioning and clinician-rated apathy. Occupational therapists (OTs) assessed functional independence and disability with the Barthel Index of ADLs (Mahoney & Barthel, 1965) and Lawton Instrumental Activities of Daily Living Scale (Lawton & Brody, 1969) at the initial intake and after the sixth session. OTs also rated the participants’ level of engagement in therapy after the sixth session using the Rehabilitation Therapy Engagement Scale (Lequerica et al., 2006). Results: Education was related to functional outcomes (ADL and IADL), whereas age, gender, and estimated premorbid IQ were not. Multiple linear regressions demonstrated that neuropsychological performance was a significant predictor of functional outcomes and therapy engagement. Therapy engagement predicted functional outcomes and was found to mediate the relationship between neuropsychological performance and outcomes. An additional set of regressions showed that therapy engagement accounted for unique variance and served as a mediator for neuropsychological performance predicting outcomes, even after accounting for education, comorbid physical health status, emotional functioning, and apathy. Conclusions: Engagement in therapy is a crucial characteristic in successful rehabilitation outcome. The findings support the hypothesis that cognitive deficits associated with ABI undermine full engagement in rehabilitation therapy, which in turn diminishes potential gains made in therapy and functional recovery. Neuropsychological assessment can enhance rehabilitation outcomes by identifying characteristics that underlie therapy engagement, which can ultimately be used to maximize the effectiveness of individualized treatment plans