Progression of socio-cognitive impairment from healthy aging to Alzheimer’s dementia: A systematic review and meta-analysis

Background: Trajectories of decline across different socio-cognitive domains in healthy older adults and in pathological aging conditions have not been investigated. This was addressed in the present systematic review and meta-analysis. Methods: MEDLINE, Web of Science Core Collection, CENTRAL, and PsycInfo were searched for studies investigating social cognition across four domains (Theory of Mind, ToM; emotion recognition, ER; Social-decision making, SD; visual perspective taking, VPT) in healthy older individuals, individuals with subjective and mild cognitive impairment (SCD, MCI) and Alzheimer’s disease (AD). Random-effects meta-analyses were conducted. Results: Of 8137 screened studies, 132 studies were included in the review. ToM and ER showed a clear progression of impairment from normal aging to AD. Differential patterns of decline were identified for different types of ToM and ER. Conclusion: This systematic review identified progression of impairment of specific socio-cognitive abilities, which is the necessary pre-requisite for developing targeted interventions. We identified a lack of research on socio-cognitive decline in different populations (e.g., middle age, SCD and MCI-subtypes) and domains (SDM, VPT)