The impact of internalizing symptoms on autistic traits in adolescents with restrictive anorexia nervosa

Background: Although previous studies indicated a positive association between restrictive anorexia-nervosa (AN-R) and autistic traits, the potential interference of psychiatric internalizing comorbidity on this association is not yet fully investigated. Materials and methods: The aim of this study was to explore autistic traits and internalizing psychopathology in adolescents (age range: 11.7–17.2 years) with AN-R. Twenty-five patients referred to two tertiary-care hospitals were compared to a large control group (N=170) with no differences in age and sex. AN-R patients and controls filled out instruments assessing autistic traits (autism spectrum quotient [AQ]), psychopathology (youth self-report [YSR] 11–18), and eating patterns (eating attitude test [EAT]). In order to disentangle the possible mediating role of internalizing symptoms on autistic traits, two separate control groups (called True and False healthy control, both composed of 25 eating-problem-free participants) were derived from the whole control group on the basis of the presence or absence of internalizing problems in the YSR. Results: AN-R patients scored significantly higher on AQ compared to the whole control group and to controls without internalizing problems (True HC), but these differences disappeared when only controls with internalizing problems (False HC) were considered. Conclusion: Autistic traits in AN-R individuals may have been overestimated and may partly be due to comorbid internalizing symptoms in investigated patients.