Family members or close contacts may spot early dementia risk first

New research using data from the English Longitudinal Study of Ageing shows that reports from family members or close contacts about an older person’s day-to-day functioning may provide an early signal of dementia risk and may be more informative than individuals’ own reports of their abilities.

The study analysed data from 1,050 ELSA participants aged 65 and over who took part in the Harmonised Cognitive Assessment Protocol. Participants completed a detailed cognitive assessment covering memory, executive function, language, and overall cognitive performance. They also reported whether they had difficulty with everyday tasks such as dressing, bathing, shopping, and managing money. Informants (people who know the participant well) provided parallel assessments of the participant’s daily functioning.

Participants were followed for almost 7 years using linked hospital records, mortality data, and self-reported doctor diagnoses to identify new cases of dementia. Although self-reports and informant reports showed broadly similar overall levels of difficulty with daily activities, agreement between the two was modest. Reports provided by informants were more strongly and consistently associated with poorer cognitive performance across domains, particularly executive function and memory. They were also strongly linked to later dementia.

Participants whose informants reported difficulties with instrumental activities of daily living, tasks that require more complex cognitive skills such as managing finances or finding their way around familiar places, had around five times the risk of developing dementia during follow up. This association remained after taking account of age, socioeconomic circumstances, lifestyle, and existing health conditions. Informant reports of problems with basic daily activities were also associated with increased dementia risk. In contrast, most self-reported impairments were weakly associated with later dementia once these other factors were considered.

Certain everyday tasks stood out. Difficulties managing money were strongly associated with poorer cognitive performance in both self- and informant-reports. However, informant reported problems involving memory and orientation, such as remembering short lists, recalling recent events or finding one’s way around familiar streets, showed some of the strongest links with subsequent dementia. These tasks may capture subtle changes in episodic memory and navigation that occur before a clinical diagnosis.

The strength of associations varied according to participant and informant characteristics. Links between informant reported impairment and cognitive performance were strongest among participants with intermediate levels of education, and when informants had higher educational qualifications or daily contact with the participant. This suggests that who reports functional change, and how closely they know the participant, may influence how well everyday difficulties reflect underlying cognitive decline.

This study indicates that informant reports of difficulties, particularly in complex and memory related tasks, may improve the identification of early cognitive decline in large scale studies. Refining functional measures in this way could strengthen dementia surveillance and support research targeting earlier stages of disease.

Gao Y, Zaninotto P, Steptoe A. Associations of self and informant reported functional impairment with cognitive performance and incident dementia. Journal of Prevention of Alzheimer’s Disease. 2026;13:100482.

Photo by Centre for Ageing Better