Longitudinal trajectories and psychological predictors of weight loss and quality of life until 3 years after metabolic and bariatric surgery

Objective
This study aimed to describe longitudinal trajectories of Total Weight Loss (%TWL), and mental and physical health related quality of life (HRQOL), as well as to identify preoperative psychological predictors of these trajectories.

Methods
A prospective observational study including Dutch patients treated with metabolic and bariatric surgery (n = 420, age 44.8 ± 10.3 years, 78.6% females) was performed. Trajectories of %TWL and HRQOL from screening to 1-, 2-, and 3-years post-surgery were described using growth mixture modelling. Multivariable and lasso regression models were used to identify predictors.

Results
Three trajectories described %TWL, varying in the degree of first-year weight loss. No pre-surgical psychological factors were associated with %TWL trajectories. We identified four physical and five mental HRQOL trajectories. Approximately 25-30% of patients exhibited patterns of initial improvements followed by decline, or persistently low levels of HRQOL. Higher depressive symptoms were associated with these unfavourable physical HRQOL trajectories (OR 1.20, 95%CI 1.04-1.39), adjusted for confounders. Unfavourable mental HRQOL trajectories were predicted by depressive and anxiety symptoms, neuroticism, insecure attachment, and maladaptive coping. In contrast, self-esteem, extraversion, and conscientiousness were associated with favourable mental HRQOL trajectories.

Discussion
Psychological factors did not predict weight loss, but they significantly impacted patient's HRQOL after metabolic and bariatric surgery. A subgroup with unsuccessful HRQOL after surgery was identified, who would benefit from tailored preoperative counselling to optimize surgery outcomes. Metabolic and bariatric surgery may not be universally beneficial for all patients, challenging the conventional approach to surgical interventions for severe obesity and advocating for a more nuanced, individualized assessment of potential candidates.