The interplay between social engagement, social connections and mental and physical health in older adults

There is a wealth of evidence on the health benefits of social engagement (an individual's participation in a community or society) and social connections (the structural, functional and qualitative aspects of individuals' relationships with others that support their social engagement). However, the moderating role of genetics in this relationship remains less clear and is currently under-researched. This is important as genetics have been shown to play an integral role in all aspects of health and behaviour. This PhD will therefore utilise advances in genome-wide association studies (GWASs) that have led to the development of polygenic scores (PGS), which are measures for potential polygenic predisposition of complex phenotypic traits. As PGSs have recently been derived for the English Longitudinal Study of Ageing (ELSA), this PhD aims to investigate the relationship between social engagement, social connections, PGSs for health and health-related phenotypes and health outcomes in older adults. Specifically this PhD will focus on two main analyses: firstly, I will investigate whether profiles of polygenic predisposition affect people's patterns of social engagement and social connections; and secondly, I will explore how gene x environment (GxE) interactions (interactions between polygenic predisposition and social engagement and connections) are associated with health outcomes. This research is timely as it will add further understanding to the mechanisms behind complex interactions between social factors and health and will add a genetic component that has not yet been fully utilised in research on associations between social engagement, social connections and health in older adults. It is hoped that this project may provide insight into the relationship between social engagement, social connections and health and enrich our understanding of how genetic factors could moderate this relationship through potential biosocial pathways leading to disease.