Exploring the associations between structural and functional aspects of social relationships and cognition in very old age.

Objectives: Few studies have examined the associations between social relationships and cognition in very old adults (80+ years). Moreover, limited research has considered structural and functional aspects of social relationships together when exploring their associations with cognition. Therefore, the present study aimed to investigate the associations between structural and functional social aspects and cognition in very old age.

Method: The sample comprised 518 two-wave participants of the NRW80+ Study, who showed no indication of dementia and an average age of 85 years at baseline (range: 80-97 years). They were assessed twice over an approximate 2-year interval. Multilevel linear growth curve analysis was employed to model cognitive development over very old age and to examine the associations between structural and functional aspects of social relationships and cognitive development. It was controlled for demographic and health characteristics.

Results: A larger social network size (ß = 0.05, 95% CI [0.02, 0.08], p = 0.002) and frequent compared with occasional, seldom, and no contact with others (ß = 0.16, 95% CI [0.03, 0.28], p = 0.013) were associated with higher global cognition in the fully-controlled model. Model comparisons further revealed that structural aspects better predicted global cognition in very old age compared to functional aspects (χ²(2) = 16.17, p < 0.001).

Conclusion: The findings underline the positive association between structural aspects of social relationships and global cognition in very old age. They also highlight the need for interventions promoting a socially active lifestyle to prevent cognitive decline in this vulnerable age group.