Self‐rated and informant‐rated everyday function in comparison to objective markers of Alzheimer's disease

Abstract

It is recognized that individuals with mild cognitive impairment (MCI) already demonstrate difficulty in aspects of daily functioning, which predicts disease progression. This study examined the relationship between self- versus informant-report of functional ability, and how those reports relate to objective disease measures across the disease spectrum (i.e. cognitively normal, MCI, Alzheimer’s disease). A total of 1,080 subjects with self- and/or informant-rated Everyday Cognition (ECog) questionnaires were included. Objective measures included cognitive functioning, structural brain atrophy, cerebrospinal fluid (CSF) abnormalities, and a marker of amyloid deposition using positron emission tomography (PET) with [18F]AV45 (florbetapir). Overall, informant-report was consistently more associated with objective markers of disease than self-report although self-reported functional status may still have some utility in early disease.

Implementation of subjective cognitive decline criteria in research studies

“…There is also evidence that the composite of both self and informant report accurately predicts hippocampal atrophy (64) and longitudinal decline at the earliest stages of disease, possibly better than self or partner report alone (5, 84). When examining the association between self- and informant-reported everyday function and brain volumes across the disease spectrum, the strength of the associations tended to be higher for the informant ratings than for self-report (10). Moreover, a recent study showed that informants’ ratings of the subjective cognitive decline questionnaire (SCD-Q) were significantly higher in preclinical AD compared to elderly controls, presenting, by contrast, no significant differences in the self-rating scores were obtained with the SCD-Q (88).…”

“…Although the number of studies reporting the relation between CSF AD biomarkers and informant ratings of SCD is low, they seem to point in the same direction. Rueda and colleagues (10) found that in a sample constituted by cognitively normal and impaired subjects, informant ratings of SCD significantly correlated with Aβ42 and ptau CSF levels and a smaller hippocampal volume. Similarly, Okonkwo and colleagues found that CSF Aβ42, tau and ptau levels correlated with informant report of functional decline in cognitively normal elders and in a MCI group (89).…”

Brain Health: The Importance of Recognizing Cognitive Impairment: An IAGG Consensus Conference

“…Informant report has a better association with disease than self-rated report. 35 The AD8 has been validated in Korea, Brazil, Spain, Japan, China, and Taiwan. 36–41 …”

The Potential Utility of Eye Movements in the Detection and Characterization of Everyday Functional Difficulties in Mild Cognitive Impairment

“…For example, Rueda et al (2014) have suggested that self report should be used early in the course of decline with later precedence given to informant ratings, whereas Tabert et al (2002) have suggested that a discrepancy score between self and informant reports may be more informative than either report interpreted in isolation. Other investigators have emphasized the need for objective assessment of functional ability that does not rely on reports by individuals impacted by these difficulties (Pereira et al 2010).…”