Background/Objectives: Psychological vulnerability in individuals with obesity represents a significant concern in the context of bariatric surgery. This study aimed to assess psychosocial functioning and identify the psychological, clinical, and sociodemographic predictors of impairment among patients undergoing preoperative evaluation. Methods: A retrospective observational study was conducted on patients referred for bariatric surgery at a single academic medical center. Data were collected through clinical interviews and validated psychometric tools: the Clinical Impairment Assessment (CIA), the Patient Health Questionnaire-9 (PHQ-9), and the Generalized Anxiety Disorder-7 (GAD-7). Robust multiple regression analysis determined associations between CIA scores and psychological and demographic factors. Results: A total of 688 patients were evaluated (median age: 46 years; 70.3% female). Most had a high school education (56.9%) and were employed (69%). Elevated scores on the Clinical Impairment Assessment (CIA) were significantly associated with female gender (β = 1.075, p = 0.029), moderate anxiety (GAD-7 ≥ 10; β = 3.85, p < 0.001), and severe depressive symptoms (PHQ-9 ≥ 15; β = 16.67, p < 0.001). Other significant predictors included prior psychotherapy (β = 1.18, p = 0.044), aesthetic motivation for surgery (β = 0.92, p = 0.120), and expectations that weight loss would improve self-esteem (β = 2.11, p = 0.001) or social relationships (β = 1.98, p = 0.002). Conversely, physical activity was associated with lower CIA scores (β = –1.23, p = 0.050). The regression model showed strong explanatory power (McFadden R² = 0.529). Conclusions: This study highlights key predictors of psychosocial distress in bariatric candidates, underscoring the importance of comprehensive psychological assessment before surgery. The CIA appears to be a valuable screening and monitoring tool. Future research should explore the longitudinal evolution of psychosocial functioning and support the integration of psychological care into multidisciplinary bariatric programs.