Informant Perspectives on the Quality of Life of Healthy Older People, and People With Dementia Living in the Community and Care Facilities.

OBJECTIVES: Quality of life (QoL) ratings for people living with dementia appear to be influenced by several factors. This study examined how informant perspectives and place of residence influence agreement between self- and informant-rated QoL of people living with dementia. METHODS: This cross-sectional observational study included 74 healthy older controls, 80 community-dwelling people living with dementia and 351 residing in residential care facilities (RCFs), along with their informants. Quality of life was assessed using the Quality of Life in Alzheimer's Disease (QoL-AD) scale. Carers provided two ratings: (i) proxy (their estimate of the person's self-rating) and (ii) opinion (their own view of the person's QoL). RESULTS: In the control group, self- and informant-rated QoL did not differ significantly. Among community-dwelling people living with dementia, self-rated QoL was higher than both proxy (mean difference 2.7, 95% CI 1.3-4.1) and opinion ratings (mean difference 5.3, 95% CI 3.8-6.8). Similarly, those in RCFs rated their QoL higher than informants. The mean difference between self and opinion rating was greater than the mean difference between self and proxy rating (7.2, 95% CI 6.0, 8.5 for opinion rating, and 5.1, 95% CI 3.8, 6.3 for proxy rating). Discrepancies were greater for people living with dementia residing in RCF than in the community. CONCLUSIONS: Informants tend to underestimate QoL in people living with dementia, particularly in residential care. Informant perspective and dementia severity may influence ratings. Researchers and service providers should consider both self- and informant perspectives when evaluating QoL in people living with dementia.