Personality Features and Defense Styles in Subjects Affected with Eating Disorders: Focus on Anorexia and Bulimia Nervosa

Abstract

Eating disorders have been reported to be characterized by a specific profile of psychological defenses. Defense mechanisms refer to involuntary psychological processes, relatively stable cognitive response patterns that may serve to distort reality whenever individual resources, skills or motivations do not ensure functional adaptation to internal or external stressful situations. The present study aims at investigating and comparing defense mechanisms and personality correlates in three subgroups of patients with eating disorders (anorexia restrictive type, anorexia bulimic/purging type, and bulimia nervosa) consecutively recruited to a regional outpatient specialist service for eating disorders. Through a retrospective chart review, we recruited 104 adult subjects with a diagnosis of anorexia nervosa (n=62) and bulimia nervosa (n=42), who were administered with Defense Mechanism Inventory (DMI), Eating Disorder Inventory-2 (EDI-2) and the Structured Clinical Interview for DSM-5® Personality Disorders (SCID-5-PD). Statistical analyses were carried out by using ANOVA and X2 test, where appropriate. The mean age of participants was 23 (±SD=8) and 26 (±SD=8) years, respectively in AN and BN sample. Amongst bulimic outpatients, clinically significant differences were found in “turning against the self” (TAS, p<0.001), drive for thinness (DT, p=0.012), bulimia (BU, p<0.001), body dissatisfaction (BD, p=0.010), interoceptive awareness (IA, p=.006) subscales and in borderline personality traits (p=0.038). Positive correlations were found between TAS subscale and the EDI-2 subscales (BU and ineffectiveness (I)); whilst negative correlations were present between TAS and obsessive-compulsive traits. Amongst anorexic outpatients, significant negative correlations were found between the DMI subscale (principalization, PRN) and EDI-2 subscales (BU, I, IA and asceticism (ASC)); whilst positive correlations between TAS and I, ASC and social insecurity (SI), particularly in anorexia restrictive type, and DMI subscale “turning against the object” (TAO) and narcissistic (p=0.05) and obsessive-compulsive personality traits (p=0.002). Significant differences were found between PRN and anorexia restrictive type (p=0.04) and TAO in anorexia bulimic/purgative type (p=0.029). Overall, anorexic subjects significantly displayed a trend for obsessive-compulsive traits. In particular, anorexia restrictive type subjects preferentially use intellectualizing defense styles, whilst anorexia bulimic/purgative type subjects use more “aggressive” defense styles. Subjects with bulimia nervosa preferentially display intropunitive defense styles and borderline personality traits. Therefore, investigating and deepening the specific pattern of defense mechanisms and associated personality traits in eating disorders may be useful from a clinical perspective to better understand the clinical course of eating disorders and to shape more individualized therapeutic interventions for eating disorders.