Summary: Subjective cognitive complaints may be the earliest detectable stages of preclinical dementia.
Source: University of New South Wales
Research led by Dr Katya Numbers from UNSW’s Centre for Healthy Brain Ageing (CHeBA) has shown that certain presentations of memory concerns by older adults are predictive of future dementia.
The findings published today in PLOS ONE highlight the importance of general practitioners in listening to their older adult patient population in relation to memory.
We found that when older adults go to their general practitioner with memory-specific subjective cognitive complaints it would be wise to take it seriously as they may predict future dementia, said Dr Numbers.
Subjective cognitive complaints refer to an individual’s self-experience of cognitive decline.
Research increasingly suggests that these subjective complaints may be the earliest detectible stage of preclinical dementia.
According to Dr Numbers, Study Coordinator of CHeBA’s Sydney Memory and Ageing Study, subjective cognitive complaints have the potential to capture everyday memory problems that are not always detected by clinical tests.
“Subjective cognitive complaints can be self-reported or reported by someone close to the individual,” said Dr Numbers.
They can refer to specific changes in memory ability or changes in other cognitive domains like language or processing speed,” she said.
The Sydney Memory and Ageing Study (MAS) investigates rates and predictors of health and cognitive decline in older adults. MAS is especially interested in when/why normally functioning adults who show evidence of memory or cognitive decline either progress to dementia or improve.
This research extends from previous work led by CHeBA which examined the relationship between self-reported memory or other cognitive concerns and those provided by family or friends, known as informants. The research assessed 873 older adults without dementia when first assessed. The study also surveyed 843 informants who knew participants well enough to comment on changes in participants’ cognitive abilities.
Professor Henry Brodaty, Leader of CHeBA’s Memory and Ageing Study and Co-Director of CHeBA, said that comprehensive neuropsychological assessments were carried out initially and second yearly for six years. Assessments were reviewed by a panel of expert clinicians who made a clinical diagnosis of dementia by consensus.
“Participant and informant memory-specific cognitive complaints were associated with the rate of global cognitive decline. If an informant noted that the person had poorer memory, six years later we found a decline in memory and executive function (planning, understanding, abstract thinking). The risk of dementia at follow-up was also greater if participants complained about poorer memory or if their informant noted changes in memory and non-memory types of cognition,” said Professor Brodaty.
The findings emphasised the importance of an older adult’s subjective presentations and the relevance of the perceptions of informants in relation to predicting cognitive decline.
“While many people with memory complaints will not develop dementia, where possible, informants should be asked to report any changes on the individual’s memory and non-memory abilities, as such symptoms increases the risk of further decline,” said Dr Numbers.
Participant and informant memory-specific cognitive complaints predict future decline and incident dementia: Findings from the Sydney Memory and Ageing Study
Subjective Cognitive Complaints (SCCs) may represent one of the earliest stages of preclinical dementia. The objective of the present study was to extend previous work by our group to examine the relationship between participant-reported and informant-reported memory and non-memory SCCs, cognitive decline and incident dementia, over a six-year period. Participants were 873 community dwelling older adults (Mage = 78.65, SD = 4.79) without dementia and 843 informants (close friends or family) from the Sydney Memory and Ageing Study. Comprehensive neuropsychological testing and diagnostic assessments were carried out at baseline and biennially for six years. Linear mixed models and Cox proportional hazard models were performed to determine the association of SCCs, rate of cognitive decline and risk of incident dementia, controlling demographics and covariates of mood and personality. Participant and informant memory-specific SCCs were associated with rate of global cognitive decline; for individual cognitive domains, participant memory SCCs predicted decline for language, while informant memory SCCs predicted decline for executive function and memory. Odds of incident dementia were associated with baseline participant memory SCCs and informant memory and non-memory SCCs in partially adjusted models. In fully adjusted models, only informant SCCs were associated with increased risk of incident dementia. Self-reported memory-specific cognitive complaints are associated with decline in global cognition over 6-years and may be predictive of incident dementia, particularly if the individual is depressed or anxious and has increased neuroticism or decreased openness. Further, if and where possible, informants should be sought and asked to report on their perceptions of the individual’s memory ability and any memory-specific changes that they have noticed as these increase the index of diagnostic suspicion.