Background: Understanding the relationship between specific behavioral and psychological symptoms of dementia (BPSD) clusters and improvements in activities of daily living (ADL) supports effective interventions for dementia. This study identified BPSD clusters and examined their association with ADL improvement in patients with dementia in subacute rehabilitation settings. Methods: This prospective cohort study included 137 patients with dementia, aged 65 years or older, admitted to a subacute rehabilitation ward in Japan. ADL and BPSD were assessed using the Functional Independence Measure (FIM) and Neuropsychiatric Inventory-Nursing Home Version, respectively. Exploratory factor analysis explored the BPSD clusters. Linear mixed models identified the factors associated with FIM score changes between admission and discharge. Results: Five BPSD clusters were identified: psychosis, behavioral disorders, affective syndrome, hyperactivity, and apathy. In the linear mixed model, higher cognitive functions were associated with greater ADL independence (β=2.136, P <0.001). A significant interaction between mini-mental status examination and time (β=−0.919, P <0.001) indicated greater improvements in participants with lower baseline cognition. Conversely, higher hyperactivity scores were associated with less ADL improvement (β=−0.454, P =0.048). Conclusions: Cognitive function and hyperactivity-related BPSD significantly influenced the functional outcomes in patients with dementia undergoing subacute rehabilitation.
Tenjin et al. (Mon,) studied this question.