Physical Exercise and Behavioral Management Interventions for Dementia Care at Home

Thesis (Ph.D.)--University of Washington, 2022Background: Due to global aging, the rising number of people with dementia (PWD) presents a looming public health crisis both in the United States and globally. Although memory and cognitive decline are the clinical hallmarks of dementia, PWD will experience a broad range of behavioral and psychological symptoms of dementia (BPSD), also known as neuropsychiatric symptoms. A growing body of evidence suggests that BPSD should be managed with non-pharmacological intervention approaches, as the frequent use of antipsychotic medications for BPSD has shown limited efficacy and serious adverse effects. Caring for a family member with dementia is particularly demanding and stressful due to the decline in physical function, behavioral disturbance, and emotional distress. As the majority of PWD receive care from family caregivers at home, home-based, dyadic, non-pharmacological interventions are important to address the needs of community-dwelling dementia care dyads. However, little is known about the effects of those interventions and how the interventions work. Objectives: This dissertation aimed to: (1) explore the current state of science on home-based, dyadic exercise and behavioral management interventions; and (2) investigate potential mediating and moderating variables of a translation study based on an evidence-based, multi-component intervention, named “Reducing Disability in Alzheimer’s Disease” (RDAD). Research Design: This dissertation consists of three studies. The first study was a systematic review to explore the effects of home-based, dyadic exercise and behavioral management interventions on physical function, BPSD, and family caregivers’ response to BPSD. We searched four databases and used the PRISMA checklist to report the review process. The results were compiled and screened by two reviewers who worked independently. We applied the narrative synthesis approach to report the findings. Risk of bias tools were used to assess the quality of each study included in the synthesis. The second and third studies were secondary data analyses using the dataset from the 2012-2016 “Reducing Disability in Alzheimer’s Disease-Northwest” (RDAD-NW) translation study. A staggered multiple baseline design was applied in RDAD-NW. Data were collected at baseline, pre-intervention (one and half months after baseline), post-intervention (three months after baseline), and at 7-month, and 13-month follow-ups. Community-dwelling dementia care dyads (N=255) were assessed at baseline. The RDAD-NW had two components: exercise and behavioral management techniques, which were delivered through nine in-home sessions over six weeks. The second study aimed to examine the extent to which exercise mediates changes in physical function of care dyads and BPSD in PWD from baseline to follow-up periods in the RDAD-NW study. Latent growth curve modeling was used to investigate the potential mediating factor using five time-point measurement data. The third study aimed to examine the extent to which behavioral management strategies mediate change in the frequency of BPSD in PWD and family caregivers’ reactions to behavioral problems in the RDAD-NW study and to investigate the extent to which the family caregivers’ sex and relationship with the care recipient moderate change in family caregivers’ mood. Structural equation modeling was used for the mediation and moderation analyses in this study. Results: In the first study, research studies on exercise interventions reported improvements in care dyads’ balance and quality of life and decreases in caregiver burden and depression. Studies on behavioral management interventions reported improved aggressive and disruptive behaviors among PWD, increased verbally communicated depressive behaviors in PWD, and improved caregiver’s knowledge, preparedness, competence, and self-efficacy. In the multi-component interventions, studies reported decreases in caregiver unmet needs and depression and improvement in PWD’s quality of life. In the second study, there were no significant mediation effects of exercise on the physical function of care dyads and behavioral problems of PWD from baseline to follow-up periods identified. In the third study, we found a positive and significant moderating effect of caregivers’ sex on the relationship between caregivers’ mood at baseline and 7-month follow-up. The moderation effect was maintained during the 13-month follow-up. However, there were no significant mediation effects of the behavioral management techniques on the frequency of BPSD in PWD and family caregivers’ reactions to BPSD between pre-and post-intervention time points. Conclusions: Female caregivers, on average, spend more time providing care than male caregivers and are more likely to experience a higher level of impaired mood. Caring for a family member with dementia significantly increases the risk of depression, which was more pronounced for female caregivers in the RDAD-NW translation study. This result highlights the need for further investigation of contributing factors to family caregivers’ emotional burden and a better understanding of the dynamics of dyadic interaction during the caregiving process. In addition, future exercise and behavioral management interventions for community-dwelling dementia care dyads should include large-scale, randomized control trials, and more rigorous methodologies. Furthermore, care dyads’ needs and perspectives on the impact of the interventions should be investigated through mixed-method approaches. Investigations regarding the long-term impact of interventions as well as factors contributing to intervention sustainability are needed. Future directions for RDAD translation may focus on extending its scope by recruiting participants from various backgrounds to increase diversity and address the needs of dementia care in different populations