Nursing home placement, day care use, and cognitive decline in Alzheimer's disease.

OBJECTIVE: People with Alzheimer's disease are often placed in a nursing home, sometimes after using adult day care services. How affected persons function during this potentially difficult transition is not well understood. The aim of this study was to examine the associations of day care use and nursing home placement with the rate of cognitive decline in Alzheimer's disease.
METHOD: The participants were 432 older persons with Alzheimer's disease who were recruited from health care settings in the Chicago area. At baseline, they lived in the community and were using day care services a mean 1.7 days per week. At 6-month intervals for up to 4 years, they completed nine cognitive tests from which a composite measure of global cognition was derived.
RESULTS: On average, cognition declined at a gradually increasing rate during the study period. Nursing home placement was associated with a decrease in the level of cognition and an acceleration in the rate of cognitive decline. Day care use at baseline was not related to cognitive decline in initial analyses, but it interacted with nursing home placement such that higher level of day care use substantially reduced association of placement with accelerated cognitive decline. Education interacted with placement such that more schooling was associated with a greater increase in cognitive decline upon nursing home placement, but prior day care use also attenuated this association.
CONCLUSIONS: Nursing home placement is associated with accelerated short-term cognitive decline in Alzheimer's disease. Prior experience in adult day care may lessen this association.