Caregiver personality predicts rate of cognitive decline in a community sample of persons with Alzheimer's disease. The Cache County Dementia Progression Study.

Background: Environmental influences on the rate of Alzheimer's disease (AD) progression have received little attention. Our objective was to test hypotheses concerning associations between caregiver personality traits and the rate of AD progression.

Methods: Care receivers (CR) were 161 persons with AD from a population-based dementia progression study; 55 of their caregivers were spouses and 106 were adult children. Cognitive status of the CR was measured with the Mini-Mental State Examination every six months, over an average of 5.6 (range: 1-14) years. Linear mixed models tested rate of cognitive decline as a function of caregiver personality traits from the NEO Five-Factor Inventory.

Results: Significantly faster cognitive decline was observed with higher caregiver Neuroticism overall; however, in stratified models, effects were significant for adult child but not spouse caregivers. Neuroticism facets of depression, anxiety, and vulnerability to stress were significantly associated with faster decline. Higher caregiver Extraversion was associated with slower decline in the CR when caregivers were adult children but not spouses.

Conclusions: For adult child caregivers, caregiver personality traits are associated with rate of cognitive decline in CRs with AD regardless of co-residency. Results suggest that dementia caregiver interventions promoting positive care management strategies and ways to react to caregiving challenges may eventually become an important complement to pharmacologic and other approaches aimed at slower rate of decline in dementia.