Psychiatric and Psychosocial Outcomes of Bariatric Surgery in Adolescents and Adult Women: A Prospective Cohort Study

Background/Objectives: The rising prevalence of severe adolescent obesity has increased the number of young patients referred for bariatric surgery. The psychiatric and psychosocial profiles of adolescents and of adult women undergoing this treatment remain insufficiently characterized. This study compared preoperative and postoperative psychiatric, psychosocial, and metabolic profiles of adolescents and adult women undergoing bariatric surgery. Methods: This prospective cohort study recruited 77 consecutive female patients (32 adolescents aged <18 years; 45 adult women aged 18–25 years) at a single bariatric center in Poland between December 2022 and December 2023. All participants underwent comprehensive preoperative and one-year postoperative assessments including laboratory testing, standardized psychiatric interviews, and psychometric screening with the Beck Depression Inventory (BDI) and the Patient Health Questionnaire-9 (PHQ-9). Results: Preoperatively, adolescents were more severely affected for their age (median BMI-for-age z-score 3.53) and waited longer between the first obesity clinic visit and surgery. Adolescents more frequently reported self-harm behaviors and moderate-to-severe depression on the BDI, whereas adult women more often reported psychoactive substance use. Both groups achieved comparable improvements in laboratory and comorbidity outcomes at one year, although relative weight loss was greater in adult women (median total weight loss 37.6% vs. 28.4%, p < 0.0001). Postoperatively, a greater proportion of adolescents than adult women improved with respect to social anxiety (50.0% vs. 13.3%, p = 0.0007) and BDI depression severity (53.1% vs. 24.4%, p = 0.02), whereas a greater proportion of adult women improved with respect to psychoactive substance use (46.7% vs. 12.5%, p = 0.003). Generalized anxiety and suicidal ideation declined within both groups, but the extent of improvement did not differ significantly between them. These differences persisted, and for several outcomes became larger, after adjustment for the reduction in BMI, which was smaller in adolescents. Conclusions: In this observational cohort, bariatric surgery was associated with distinct psychiatric and psychosocial outcome profiles in adolescents compared with adult women. Because the study was uncontrolled and included no non-surgical comparison group, these findings are hypothesis-generating and cannot establish a causal effect of surgery or of its timing; confirmation in larger, multicenter studies with appropriate comparison groups is required. Comprehensive multidisciplinary perioperative care and tailored postoperative psychological support appear important for both age groups.