Weight loss trajectories and psychobehavioral predictors of outcome of primary and reoperative bariatric surgery: a 2-year longitudinal study

Background: Long-term behavioral and psychological aspects associated with weight outcomes after reoperative bariatric surgery have rarely been investigated.

Objectives: This study sought (1) to identify differences in weight loss trajectories during the first 24 months in reoperative bariatric surgery (R group) and primary bariatric surgery (P group) and (2) to investigate pre- and postsurgery psychobehavioral predictors of weight loss and weight regain for both groups.

Setting: Hospital center and university, Portugal.

Methods: This longitudinal study compared an R group (n = 157) and a P group (n = 216). Patients were assessed at presurgery and at 6, 12, 18, and 24 months postsurgery. Assessment included the Eating Disorder Examination-Questionnaire and Repetitive Eating Questionnaire diagnostic interviews and a set of self-report measures assessing eating disorder symptomatology, grazing, depression, anxiety, and impulsive behavior.

Results: The P and R groups presented a similar trajectory for the percentage of total weight loss (%TWL) (β = 1.46, standard error = 1.96; Wald χ² = .55, P = .457) and weight regain (β = 1.66, standard error = 2.72; Wald χ² = .24, P = .622). No significant presurgery predictors of weight loss and weight regain were found for the P and R groups. Regarding postsurgery predictors, higher Eating Disorder Examination-Questionnaire scores (Wald χ²₍₁₎ = 6.88, P = .009) and grazing behavior (Wald χ²₍₁₎ = 8.30, P = .004) were associated with less %TWL for both groups. Belonging to the P group emerged as a significant predictor of more weight loss (Wald χ²₍₁₎ = 7.25, P = .007). Postsurgery anxiety predicted less %TWL in R group (Wald χ²₍₁₎ = 3.89, P = .043). Considering weight regain, higher postoperative disordered eating (global Eating Disorder Examination-Questionnaire; Wald χ²₍₁₎ = 4.66, P = .031) was associated with increased weight regain for the P and R groups.

Conclusions: Problematic eating behaviors and psychological distress are significant predictors of poor weight outcomes for both groups.