Increased worry associated with self‐reported, but not informant‐reported, subjective cognitive decline predicts risk of incident dementia

Abstract

AbstractBackgroundSubjective cognitive decline (SCD), in the absence of impaired testing, may be an indicator of early Alzheimer’s disease (AD) and other dementias. However, not all individuals with SCD have cognitive decline. ‘SCD plus’ criteria were proposed in an effort to increase the likelihood of identifying preclinical dementia in individuals with SCD. Two of these criteria include the expression of concern (worry) about the SCD and confirmation of the SCD by an observer (informant). This study investigates whether longitudinal changes in self‐ and informant‐reported SCD‐worry are associated with increased risk of incident dementia over time.MethodParticipants were 873 older adults (M = 78.65‐years; 55% female) and 849 informants from the Sydney Memory and Ageing Study. SCD‐worry was defined as responding “Yes” to the following: “Have you noticed growing difficulties with your/their memory?” and “Have you been concerned about your/their memory getting worse?”. Changes in SCD‐worry over time were modelled using latent growth curve analyses with logit transformation. Participants’ and informants’ propensity to report SCD‐worry at baseline and change over time were analysed using Cox regressions to determine associations with incident dementia risk over 10‐years.Results32% of participants who reported noticing memory difficulties at baseline also reported worry associated with this, where only 19% of informants reported worry associated with SCD at baseline. Controlling for demographics, APOE4, mood and personality, participants’ initial level (p < .001) and change in SCD‐worry over time (p = .002), were associated with dementia risk. Controlling for the same covariates, informants’ initial SCD‐worry (p < .001) was associated with dementia risk, though SCD‐worry change was not (p = .862). When modelled together, participants’ initial level of, and longitudinal change in, SCD‐worry were still independently associated with increased dementia risk (p’s < .001); informants’ initial SCD‐worry remained significant (see Table 1).ConclusionOur findings highlight the need to factor in concerns held by individuals that go beyond just recognising cognitive changes have occurred, as the latter is a common phenomenon in older adults. Our results suggest that worries about perceived cognitive changes may characterise individuals at greater dementia risk.