Mind & Well-being : The relationships between personality and health related pathology

Abstract: The study of the associations between personality, lifestyle and health related pathology has revealed important associations. These include associations with physical health such as the onset of cardiovascular disease, but also with mental and emotional health such as depression or life satisfaction. However, certain gaps in knowledge and methodology had persisted. This thesis contains several works that address those gaps and extend the knowledge and methodology in personality-related research.Study I utilized the large-scale UK Biobank cohort to examine personality traits in association with stroke risk. Proxy variables for the Big Five personality traits were inferred from the available data. Results indicate negative associations of the personality traits diligence and sociability, with incident stroke risk, suggesting potential protective effects.Study II employed Mendelian randomization to investigate causal relationships between specific subcategories of neuroticism and different subtypes of cardiovascular disease. Using the UK Biobank cohort, the study showed causal positive associations between depressed affect and two subtypes of cardiovascular disease: heart failure and myocardial infarction.Study III examined the associations between job satisfaction and personality traits related to executive functions: delay discounting, risk-taking, and sensation seeking. Proxy variables were created to infer delay-discounting and sensation seeking. Using data available in the UK Biobank, the study reveals a negative association between delay discounting and job satisfaction, and a positive association between risk-taking and job satisfaction.Study IV explored the association between genetic risk for autism spectrum disorder (ASD) and well-being in the general public, regardless of ASD diagnosis. The study employs polygenic risk scoring in the UK Biobank cohort and shows that the genetic risk for ASD is associated with all five well-being spectrum traits in a detrimental way, emphasizing the potential impact of a genetic predisposition for ASD on well-being.Finally, in Study V, the research proposed a novel method for studying general personality in Drosophila melanogaster. The method includes a new experimental environment, comprehensive recording and tracking, and subsequent analysis techniques, providing a foundation for further research into personality-like traits in the species.Overall, this thesis extends the knowledge and methodology in personality-related research and highlights the potential impact of personality traits on physical and mental well-being.