Meta-Analysis of Theory of Mind in Anorexia Nervosa and Bulimia Nervosa: A Specific Impairment of Cognitive Perspective Taking in Anorexia Nervosa?

WOS: 000386226800001PubMed ID: 27425037Objective: Deficits in theory of mind (ToM), ability to infer mental states of others, can play a significant role in interpersonal difficulties and/ or unawareness of illness observed in AN and other eating disorders including bulimia Nervosa (BN). Method: Current meta-analysis aimed to summarize available evidence for deficits in ToM in AN and BN and examine the effects of number of study-level variables on observed findings. In this meta-analysis, 15 studies (22 samples with eating disorders) investigating ToM performances of 677 individuals with AN or BN and 514 healthy controls were included. Results: AN was associated with significant deficits in ToM (d=0.59) which were more pronounced in the acute patients (d=0.67). Small sized deficits in ToM were observed in BN (d=0.34) and recovered AN (d=0.35). Both cognitive perspective-taking (ToM-PT) (d=0.99) and decoding mental states (ToM-decoding) (d=0.61) aspects of ToM were impaired in acute AN. ToM-decoding impairment in BN was modest. There was no evidence for significant ToM-PT deficit in BN. Several study-level variables including longer duration of illness, lower BMI, and depressive symptoms were associated with more severe deficits in ToM in AN. Discussion: ToM deficits, particularly in ToM-PT, can be a specific feature of AN but not BN. ToM impairment can contribute to poor insight, treatment resistance, and social impairment in AN