Investigating the associations between personality traits and quality of life outcomes following bariatric surgery

Introduction: Obesity presents significant challenges to health and quality of life (QoL). Bariatric surgery is regarded as the gold standard treatment for obesity, often resulting in significant weight loss, resolution of obesity-related comorbidities, and improved QoL. However, QoL outcomes are not equivocal for all who undergo surgery and there is a lack of clarity regarding the processes which impact these. This research aims to clarify the relationship between personality traits and QoL outcomes among the post-surgical bariatric population through two distinct yet complimentary studies. Specifically, 1) to systematically identify and synthesise empirical evidence regarding personality and QoL among post-surgical bariatric patients in Study 1, and 2) to further empirical knowledge by examining the processes which explain this relationship in Study 2.

Methods: Study 1 (systematic review) investigated associations between personality traits and QoL outcomes among post-surgical bariatric patients across four databases, yielding five articles for inclusion. Results were analysed and reported via narrative synthesis. Study 2 (empirical study) featured a cross-sectional design with (N = 253) post-surgical bariatric participants to investigate and explain the relationship between personality traits and QoL domains (environmental, physical, psychological, and social) via social support as a mediator.

Results: Study 1 presented emerging evidence that personality traits impact HR-QoL outcomes following bariatric surgery. HR-QoL outcomes varied according to agreeableness, extraversion, and neuroticism. Study 2 identified direct effects for: agreeableness, extraversion, and neuroticism with all QoL domains. Exploratory analysis yielded direct effects for conscientiousness, and openness upon specific QoL domains. Indirect effects of social support mediated associations between agreeableness, extraversion, and neuroticism, with all QoL domains.

Conclusions: This thesis evidences the role of personality traits in QoL outcomes among post-surgical bariatric patients and identifies the psychosocial processes which underlie the pathways to QoL. Novel findings regarding environmental QoL outcomes are also presented. Specifically, the thesis offers emerging evidence for the nuanced role of agreeableness, neuroticism, and extraversion, upon physical QoL outcomes, explained through social support. Despite the limitations of both studies, findings within this thesis offer important advancements to the evidence-base and contribute valuable implications for clinical practice.