Autistic Characteristics in Anorexia Nervosa and Its Relationship with Anxiety, Depression and Eating Habits

Background: The Autism Quotient (AQ) (Baron-Cohen et al., 2001) is a 50-item screening questionnaire that is broadly used in clinical practice regarding the identification of autistic characteristics in adult population. The participant must choose the most suitable out of four alternatives (‘Strongly agree’, ‘Slightly agree’, ‘Slightly disagree’, ‘Strongly disagree’). This tool has been shown to be useful in the detection of autistic characteristics in different psychiatric populations (Sizoo et al., 2009; Lugnegård, 2015). A special case is that of anorexia nervosa (AN). In a meta-analysis on the use of AQ in population with AN (Westwood et al., 2016), it was found that patients with AN presented higher scores in AQ compared to healthy controls. This suggests a possible relationship between autistic traits and the development of eating disorders.

Objectives: The aim of this study is to explore the relation of autistic characteristics with eating behaviors in a sample of young people with AN, as well as their relation with anxiety and depression symptoms.

Methods: Thirty adolescents and young adults (27 women and 3 men; mean age 16.43 years, sd 2.5) were asked to complete the AQ, as well as the Beck Anxiety Inventory (BAI) (Beck & Steer, 1988), the Beck Depression Inventory (BDI-II) (Beck, Steer & Brown, 1996), and the Eating Disorder Inventory (EDI-3) (Garner, 2002). The sample was divided by taking the median in the AQ score as the cutoff point and comparing the scores in the BAI, BDI-II and EDI-3. Finally, correlations between autism scores and measures of anxiety and depression, as well as eating behaviors were explored.

Results: The results suggest that there are no differences between both, above- and below-AQ median groups, in the three clinical measures (p <.05). Scores on anxiety, depression and eating behaviors do not present significant correlations with the AQ total score. One of the five subscale of the AQ (Communication) shows significantly correlations with anxiety (r=0.63), depression (r=0.67), and eating behaviors (r=0.61), but only in the above-AQ median sample.

Conclusions: These findings shed light on the role of autistic traits in young population suffering from AN. The results found here suggest that eating disorders are not directly related with the presence of autistic traits. Also, it seems that autistic characteristics do not play a main role in the emergence of anxious or depressive symptoms among these population. A lack of communication skills seems to be related to the psychiatric symptoms described above. Some limitations of this study are the reduced number of participants, as well as the lack of a comparison non-clinical group. Further investigation of autistic traits in this population, as well as their first-degree relatives, could be of interest.