RESUMO
OBJECTIVES: The aim of this study was to investigate factors associated with functioning in participants with and without borderline personality disorder (BPD). In particular, we were interested whether mentalizing and related social cognitive capacities, as factors of internal functioning, are important in predicting psychosocial functioning, in addition to other psychopathological and sociodemographic factors. METHOD: This is a cross-sectional study with N = 53 right-handed females with and without BPD, without significant differences in age, IQ, and socioeconomic status, who completed semi-structured diagnostic and self-report measures of social cognition. Mentalizing was assessed using the Reflective Functioning Scale based on transcribed Adult Attachment Interviews. A regularized regression with the elastic net penalty was deployed to investigate whether mentalizing and social cognition predict psychosocial functioning. RESULTS: Borderline personality disorder symptom severity, sexual abuse trauma, and social and socio-economic factors ranked as the most important variables in predicting psychosocial functioning, while reflective functioning (RF) was somewhat less important in the prediction, social cognitive functioning and sociodemographic variables were least important. CONCLUSIONS: Borderline personality disorder symptom severity was most important in determining functional impairment, alongside trauma related to sexual abuse as well as social and socio-economic factors. These findings verify that BPD symptoms themselves most robustly predict functional impairment, followed by history of sexual abuse, then contextual factors (e.g. housing, financial, physical health), and then RF. These results lend marginal support to the conceptualization that mentalizing may enhance psychosocial functioning by facilitating social learning, but emphasize symptom reduction and stabilization of life context as key intervention targets.