The Cost of Disconnection: Longitudinal Egocentric Network Analyses Linking Social Isolation to Loneliness and Mental Health in Adolescents and Adults

Background: Social disconnection has been proposed as a contributing factor to the youth mental health crisis. However, it remains unclear how social disruptions reshape social networks and their links to mental wellbeing across age groups. The present study examined whether social disruptions (during the COVID-19 pandemic) reshape social networks and how changes in social networks differently relate to mental health and loneliness in adolescents compared to adults. Methods: The study used egocentric network analysis of data from 1,278 participants (88% female; aged 11-89 years, mean = 37.2±16.2 years) in the multinational (Australia, the U.K., and U.S.) prospective COVID-19 Risks Across the Lifespan (CORAL) Study. Social network properties of structural density, functional closeness, and interaction frequency were derived. Linear mixed-effects modelling was employed to examine cross-sectional and prospective associations with mental wellbeing at baseline, three-month, and six-month follow-up.Results: Adolescents reported more virtual interactions, and less in-person contact. Greater network closeness was associated with lower depression, whereas dense but less close networks were linked to greater loneliness. Reduced contact from pre-pandemic levels were also linked to poorer wellbeing, particularly among younger individuals. Conclusions: The present findings highlight that age differences in social experiences, such as social network structure (density) and function (closeness and interaction frequency), may underlie young people’s greater mental health vulnerability during social disruptions. This underscores the importance of developing age-sensitive and context-responsive strategies to better support mental wellbeing during times of social disruption.