Perceived non-shared environment, personality traits, family factors and developmental experiences in bulimia nervosa.

OBJECTIVE: The role of perceived non-shared environmental influences and personality traits in the risk of developing bulimia nervosa (BN) was compared in 40 women with BN and their non-eating disordered sisters.

METHODS: The two sisters were compared for (a) eating pathology, (b) perceived non-shared environmental factors (differential family relationships, developmental teasing, traumatic experiences), (c) personality traits (impulsivity, affective instability, narcissism), and (d) psychopathology (anxiety, depression).

RESULTS: Specific perceived non-shared risk factors (e.g. perceptions of teasing), nonspecific non-shared risk factors (e.g. insecure paternal attachment) and personality traits (e.g. narcissism) distinguished women with BN from sisters. In the final logistic regression, insecure paternal attachment predicted the risk for BN, while trends were apparent for narcissism and developmental teasing after controlling for psychopathology.

CONCLUSIONS: Our correlational cross-sectional design does not allow for investigation of direction of effects. However, it is an important first step in identifying possible perceived non-shared environmental influences and personality traits that may constitute vulnerability factors predisposing individuals to the development of BN. Findings are discussed in the light of existing models of risk factors for the etiology of BN.