The correlation between anorexia nervosa and childhood traumatic experience: the mediating role of impulsivity

BACKGROUND: The pathogenesis of anorexia nervosa (AN) involves multiple factors, among which childhood traumatic experience has attracted attention. Emotional abuse, as a form of trauma, may exert a predictive effect on AN. In addition, childhood traumatic experience is closely linked to impulsivity, yet the trauma-impulsivity-AN mediation pathway has not been directly validated. The purpose of this study is to compare differences in childhood traumatic experience of patients with different subtypes of AN, as well as exploring the mediating role of impulsivity between emotional abuse in childhood traumatic experience and symptom severity of AN. METHODS: This study included 157 female patients with AN, including 76 with the restricting type (AN-R) and 81 with the binge-eating/purging type (AN-BP), as well as 124 matched healthy controls (HC). Childhood traumatic experience was evaluated using Early Trauma Inventory-short form (ETI-SF), impulsivity assessed by Barratt Impulsiveness Scale 11th Version (BIS-11), and clinical characteristics via Eating Disorder Examination-questionnaire (EDE-Q 6.0), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). Furthermore, inter-group differences in childhood traumatic experience were determined by one-way analysis of variance and analysis of covariance, the correlation between childhood traumatic experience and AN by Pearson correlation analysis, and the mediating role of impulsivity between emotional abuse and symptom severity was clarified by the Bootstrap method. RESULTS: Cases in the AN-BP group had significantly higher exposure to childhood traumatic experience compared with the AN-R and HC groups (both p < 0.05). Significant differences were likewise observed in emotional-abuse scores across the three groups (F = 10.574, p= 0.000, partial η² = 0.084). Emotional abuse was positively correlated with impulsivity and symptom severity of AN (both p < 0.05). In addition, the mediation effect of impulsivity between emotional abuse and symptom severity was 0.073 (95% CI 0.013 ~ 0.153), with an effect proportion of 19.363%. CONCLUSION: AN-BP patients have more significant childhood traumatic experience than AN-R patients, and difference was mainly reflected in the emotional abuse factor. Emotional abuse has established correlation with impulsivity and symptom severity in AN, with impulsivity playing a mediating role between emotional abuse and symptom severity.