Meaningful ties: a longitudinal mixed-methods study of ego health networks among Brazilian and Venezuelan immigrants in Portugal

Social networks are key social determinants of migrants’ health, yet they remain understudied despite undergoing significant changes in composition and structure throughout the migration process. This study explores how migrants’ health-specific social networks evolve, focusing on tie strength (weak vs. strong) and structural holes (efficiency and constraint). A mixed-methods longitudinal diary study was conducted online with a convenience sample of two of Portugal’s most representative immigrant groups: Brazilians ( n = 17) and Venezuelans ( n = 15). An ego-network questionnaire was administered at three time points over the course of 1 year (January 2021, April 2021, and between October and December 2021), along with interviews in the first and final months (January 2021 and January 2022) to explore migration aspirations and trajectories. Qualitative data were analyzed using thematic analysis, while multilevel correlations were computed between network measures. Results showed that the Brazilian immigrants had more structural holes (i.e., fewer constraints and more efficiency) and had weaker ties. In contrast, Venezuelan immigrants’ networks primarily consisted of strong ties with high constraints over time, which did not decrease efficiency. Qualitative results revealed contrasting and aligned patterns: Brazilian immigrants identified social and cultural motivations for migration, whereas Venezuelan immigrants described their migration as forced, often driven by concerns for safety. The results show how aspirations to migrate can be reflected in the structure of social networks over time, determining the resources that are activated in the network depending on the migratory planning or adaptation stage, as well as health-related crises. Social network analysis can enrich the understanding of social capital and inform tailored intervention strategies for different immigrant groups at their destination.