Understanding the relationship between bariatric surgery and mental health outcomes: a systematic review and meta-analysis

Obesity is a global health problem associated with a large range of physical and psychological comorbidities. Bariatric surgery is a technique utilised in the management of physiological aspects of obesity, however this often does not address underlying mental health symptoms. The purpose of the current study was to conduct a systematic review and meta-analysis to investigate the relationship between bariatric surgery and four key mental health outcomes: anxiety, depression, disordered eating and quality of life. A total of 42 articles contributing 101 samples (N=6,541) were included. In the main analyses conducted, a positive, significant relationship with small to medium effect sizes were identified between bariatric surgery outcomes and reduced depression (r=0.33), anxiety (r=0.18), disordered eating (r=0.32) as well as increased quality of life (r=0.27). Moderation analyses were conducted to explore relationships with age, gender, primary language, bariatric surgery type, pre- and post-surgery BMI, and time differences between baseline and follow-up measurements. Significant relationships were identified between gender and disordered eating, as well as the time between measurement points with both depression and disordered eating. Overall, the current study reinforced key findings previously established in the literature as well as identifying several critical areas for further research within the field.