HOW AUTISTIC ARE ANORECTIC FEMALES? SIMILARITIES AND DIFFERENCES BETWEEN ANOREXIA NERVOSA AND AUTISM SPECTRUM DISORDERS

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1 Clinical Neuropsychiatry (016) 13, 4/5, HOW AUTISTIC ARE ANORECTIC FEMALES? SIMILARITIES AND DIFFERENCES BETWEEN ANOREXIA NERVOSA AND AUTISM SPECTRUM DISORDERS Natalia Jermakow, Aneta Brzezicka Abstract Objective: Many studies have shown the prevalence of a higher level of autistic traits in females diagnosed with Anorexia Nervosa (AN) in comparison to healthy females. Some studies also reported a lower level of empathy and Theory of Mind (ToM) in AN, but other studies failed to confirm that result. A lower level of empathy and ToM has been consistently reported in people with Autism Spectrum Disorder (ASD). This pattern of results suggests that AN could be a form of ASD in the female population. We tested this hypothesis in the current study. Method: Participants were compared on the Empathy Quotient, Autism Quotient, Interpersonal Reactivity Index, and Reading the Mind in The Eyes test. Our results showed that there were no differences between AN and ASD groups on the Autism Quotient scale, and that both groups had significantly higher levels of autistic traits than the two (female and male) comparison groups. The AN group differed significantly from the ASD group in empathy level and ToM, exhibiting results similar to the comparison groups. Results and conclusions: Our results suggest that there are some similarities between AN and AS groups when comparing them on different dimensions of social and emotional functioning. However, these similarities only partly support the notion that AN is a form of female autism. Key words: anorexia nervosa, Asperger syndrome, empathy, autistic traits, Theory of Mind Declaration of interest: there is no financial competing interest (political, personal, religious, ideological, academic, intellectual, commercial or any other) in relation to this manuscript Natalia Jermakow, Aneta Brzezicka University of Social Sciences and Humanities, Warsaw Institutional address: ul. Chodakowska 19/31, Warsaw, Poland Corresponding author Natalia Jermakow, GamesLab S105, University of Social Sciences and Humanities, Chodakowska 19/31, Warsaw, Poland njermakow@gmail.com Introduction The most important question posed by the present study is how many autistic traits are present in females suffering from Anorexia Nervosa (AN). AN and Autism Spectrum Disorders (ASD) are disabilities that are characterizing by different symptoms. Earlier studies presents ambiguous results, especially in Theory of Mind (ToM) and empathy levels (Baron-Cohen and Wheelwright 004, Fernández-Abascal et al. 013), therefore, in this study we would like to compare those traits with the additional scales of the Interpersonal Reactivity Index (Davis 1980), and the full version of the Autism Quotient scale (Baron-Cohen et al. 001) and split the test measuring ToM into the emotions valence (positive, negative, neutral). Autism Spectrum Disorders Autism Spectrum Disorders (ASD) are the complex of neurodevelopmental disorders including Autistic Disorder, Asperger Disorder, and Pervasive Developmental Disorder not otherwise specified (PDD-NOS). The major impairments are placed into two areas problems with the social interaction and interpersonal communication and restricted, repetitive interests, behaviours and overall activity (DSM-V 013). Beginning on the symptoms is started in the early stages of the development (before 3 year old). Due to the difficulties with differentiation (e.g. High Functional Autism, HFA; Asperger Syndrome, AS), and occurring concomitant disorders, the diagnosis and symptoms severity may vary during the life (Daniels and Mandel 014). In the earlier classifications ASD into independent disorders rather than the spectrum of disorders as it has been described in the newer classifications as DSM-5 where the intensity of the symptoms lying on the continuum (DSM-IV 000, also see DSM-V 013). The diagnostic process includes verification of the occurrence of stereotypic and perseverative behaviours, excessive reaction in stressful situations, tendency to abnormal preferences on objects, eating, activities (e.g. arranging items in order) as well as problems with the social interactions and abnormal lack of the emotion expression and aversion to the physical contact (e.g. cudding). In AS those symptoms have less intensity than in HFA or even, in case of the good social adaptation, they could not be manifested. The differences between Submitted May 016, accepted July Giovanni Fioriti Editore s.r.l. 53

2 Natalia Jermakow, Aneta Brzezicka HFA and AS lying on the symptoms intensity and intelligence level. The intelligence tests are used to differ between AS, in which intelligence level is on the normal or higher level and other Developmental Disorders, in which intelligence could be lower than average (Ozonoff, South and Miller 000). Anorexia Nervosa Anorexia Nervosa (AN) is one of the eating disorders, in which significant underweight, being on restrictive diets and overmuch physical exercise are the major symptoms. Other major symptoms of AN are the low weight, less than 85% of expected in the actual age, more than 3 months absence of menstruation. Diagnosis of AN obtain approximately 1-% females (and 0.% males), and the onset frequently appears in the adolescents. Less than 50% individuals obtain the full recovery, and the most individuals have the stages of remissions and follow-ups. AN have a high mortality rates from somatic causes and the suicidal behaviours and often concomitant other psychiatric disorders (Watson and Bulik 013). There are two types of the AN: restrictive with the restrictive food intake, and binge eating/purging type with the episodes of the overeating and self-induce vomiting as well as use of laxatives, diuretics, or enemas (DSM-V 013). Diagnostic process of the AN includes the differentiation between AN and other disorders results from somatic or environmental (transient reaction to stressful situation) bases. Moreover, what is crucial that women with AN have excessive self-control and lack of cognitive flexibility (Mandy and Tchanturia 015). Similarities between AN and ASD Although having disparate characteristics, presented above two disabilities are similar in numerous of processes and mechanisms (Zücker et al. 007, Baron- Cohen et al. 013). Interesting is that occasionally Eating Disorders and Autism Spectrum Disorders occur in the one person. In other words, tendency to both eating impairments in ASD (Rastam 008) and autism spectrum traits in AN (Courty et al. 013) are more frequent than in normal population. In case of the cognitive level, previous findings have shown that AN patients have deficits similar to those suffering from Autism Spectrum Disorders (ASD) (Gillberg and Råstam 199, Zucker et al. 007, Hambrook et al. 008). A leading researcher of this topic, prof. Janet Treasure, even postulates that AN is a female type of ASD. Her model indicates several similarities in the neurocognitive profiles of both disorders. She compares major aspects of cognitive and social functioning that are impaired in both AN and ASD and concludes that patients of both conditions have a tendency to focus on local aspects of visual information processing (Weak Central Coherence) (Frith and Happe 1994) and have lower empathy and higher systematizing than non-patient groups (The Empathizing/Systematizing Theory) (Baron-Cohen 00). Both disorders are also characterized by lower cognitive control, including flexibility (The Executive Dysfunction Theory) (Hill 004). Differences between AN and ASD Besides these striking similarities, other studies have shown some discrepancies between AN and ASD groups on Theory of Mind (ToM) - the ability to recognize the mental states of other people - and empathy. ASD groups usually have lower levels of empathy (Lawson et al. 004, Baron-Cohen et al. 001), more impairments in ToM (Frith and Happe 1994, Oldershaw et al. 011), and higher levels of autistic traits (Baron-Cohen et al. 001) than AN (Oldershaw et al. 011) or comparison groups (Baron-Cohen et al. 001). There are also studies showing significantly lower ToM in the AN group than in healthy females (Harrison et al. 009), but those results are contradicted by other studies where females with AN have normal levels of empathy (Baron-Cohen et al. 013) and ToM (Adenzato et al. 01). In a direct comparison between AN and ASD, the first group had higher levels of empathy and lower levels of autistic traits (Courty et al. 013). In the current study we directly compared AN and ASD groups on empathy, autistic traits, and Theory of Mind in order to verify the assumptions about their striking similarities formulated by Treasure (Oldershaw et al. 011). We should observe no difference between AN and ASD groups in the level of empathy, ToM, and level of the autistic traits (but they should differ from the healthy comparison groups). Method Participants Participants from ASD and AN groups were meet the diagnostic criteria of ICD-10 to the proper disorder. AN group was diagnosed by the psychiatrists and all of the patients have diagnosis of the restrictive subtype of AN and participate in the group psychotherapy with psychiatrist and clinical psychologist. The BMI of patients during the collected the data was One female has the extreme stage of AN with BMI 14 kg/m (< 15kg/m), two females have the moderate stage with BMI 16 kg/m ( kg/m) and seven females have mild stage with BMI from 17 to (>= 17 kg/m), BMI index from one person did not obtain. Participants from ASD group was males having therapy and social meetings in the institution supporting ASD persons. Diagnosis of the Asperger Syndrome, but not the High Functional Autism was the inclusive criterium of the participating in the study. One person with the AS diagnosis was pretending to the HFA diagnosis, but it was not confirmed. Participants were assigned to two clinical groups and to a healthy comparison (HC) group. The first group consisted of females diagnosed with Anorexia Nervosa (n = 11, 18-3 years old; M = 6.80, SD = 4.3) and group two of males with Asperger Syndrome (n = 10, years old; M = 8.30, SD = 9.5). The healthy comparison group was splited into female (HC females) (n = 33, 19-8 years old; M = 1.33, SD = 1.4) and male (HC males) (n = 7, 19-4 years old; M = 1.76, SD =.0) students of science and humanities. The HC groups were students of humanities as well as science studies. Participants from all groups took part in the study by the fulfill the paper forms of the questionnaires. The concomitant impairments was verify by the declaration about the other diagnoses. Materials Empathy Quotient (EQ). EQ is a self-report questionnaire created by Baron-Cohen (Baron-Cohen 54 Clinical Neuropsychiatry (016) 13, 4/5

3 Similarities and differences between anorexia nervosa and autism spectrum disorders and Wheelwright 004) that contains 40 items about preferences and everyday situations with a 4-degree answer scale. This questionnaire included affective and cognitive aspects of empathy, which are understood as two aspects of the same construct. Autism Quotient (AQ). AQ is a self-report questionnaire with a 4-degree answer scale in which 50 items are divided into 5 subscales: Social Competences [AQSC], Attention Switching [AQAS], Focus on Details [AQFD], Communication [AQCom], and Imagination [AQIm]. This scale measures increases of autistic traits in both healthy populations as well as in clinic groups (Baron-Cohen et al. 001). Interpersonal Reactivity Index (IRI). IRI is a selfreport questionnaire containing 8 items that are responded to using a 5-point Likert scale. The scale was created by Davis (Davis 1980) as a tool to measure both aspects of empathy. IRI is divided into 4 subscales. Two of them measure the affective aspects of empathy (Empathic Concern [IRIEC], Personal Distress [IRIPD]) and the other two its cognitive aspects (Perspective Taking [IRIPT], Fantasy [IRIF]). Reading the Mind in the Eyes (RME). RME (Fernández-Abascal et al. 013) was created to test affective Theory of Mind, defined as the ability to read the mental states of other people. This test contains 36 photographs of people expressing different complex emotions. Four possible answers are placed in the four corners of every picture. We also divided answers according to three valences of emotions (positive, neutral, negative). Procedure All participants received EQ, AQ, IRI questionnaires and the RME test, as well as written and verbal instruction regarding the procedure and how to fill out the measures and make responses. Participants were also informed about the anonymity of research and results, and that they could resign from the study at any time. All participants completed the paper forms of the questionnaires. The whole procedure lasted between 10 and 30 minutes. One participant from the Anorexia Nervosa group had to be removed as a deviant participant because her AQ results were significantly lower. Results AQ The AQ data were analyzed with a mixed-design ANOVA in a 4 (between subjects factor - group: AN, ASD, HC females, HC males) x 5 (within subjects factor AQ subscale: Social Competences, Attention Switching, Focus on Details, Communication, Imagination) scheme. Analysis results revealed a main effect of group, F(3,76) = 7.85, p < 0.001, η p = Subsequent post hoc analysis revealed that the AN and ASD groups did not differ significantly, but that both groups had overall higher scores on AQ than both comparison groups. A significant main effect of AQ subscale was also found, F(4,304) =.31, p < 0.001, η p = 0.7. Participants had higher results on Attention Switching and Focus on Details than Communication, Social Competences, and Imagination subscales. Finally, there was a significant group x AQ subscale interaction effect, F(1,304) = 1.91, p < 0.05, η p = The ASD group differed from HC females on Communication and Imagination subscales and from HC males on the Imagination subscale (table 1). Table 1. Results of simple effect analyses for all scales and tests that were used in the study ASD AN HC males HC females mean SD mean SD mean SD mean SD EQ overall AQ overall AQ Social Competences , AQ Attention Switching AQ Focus on Details AQ Communication AQ Imagination IRI overall IRI Empatic Concern IRI Personal Distress IRI Perspective Taking IRI Fantasy RME overall RME positive emotions RME neutral emotions RME negative emotions ,,3 - Lower subscripts indicate differences between means the same subscripts = no significant differences, different subscripts = significant differences. - Results of main effect analyses are presented with Greenhouse-Geisser correction. - Results of post hoc analyses are presented with Games-Howell correction Clinical Neuropsychiatry (016) 13, 4/5 55

4 Natalia Jermakow, Aneta Brzezicka Figure 1. Scores of AQ as a function of group and subscale The AN group differed from HC females on the Communication and Imagination subscale and from HC males on the Imagination subscale. The interaction effect is presented on figure 1. EQ The EQ data were analyzed using a one-way ANOVA where group identity (AN, ASD, HC females, HC males) was a four level between subjects factor. Analysis results showed that the groups differ significantly in EQ, F(3,76) = 9.6, p < 0.001, η p = Post hoc analysis revealed that the ASD group differed from the AN group and HC females but not from HC males, whereas the AN group differed from HC males but not from HC females (see table 1). RME Emotions Mixed-design ANOVA in a 3 (within subject factoremotion: positive, negative, neutral) x 4 (between subject factor- group: AN, ASD, HC females, HC males) scheme showed a main effect of emotions, F(,15) = , p < 0.001, η p = There was also a main effect of group, F(3,76) = 8.08, p < 0.001, η p = 0.4. Additional post hoc analysis revealed that the ASD group had the lowest results while the AN group achieved the highest (see Table 1). The interaction effect was not statistically significant, F(6,15) = 1.46, p = 0.03, η p = Neutral emotions were recognized significantly more accurately than other emotion types in all groups. IRI Mixed-design ANOVA in a 4 (between subject factor- group: ASD, AN, HC males, HC females) x 4 (within subject factor- subscale: IRIEC, IRIPD, IRIPT, IRIF) scheme revealed a main effect of group, F(3,76) = 3.79, p < 0.05, η p = Additional post hoc analysis indicated differences between the ASD group and HC females only (see table 1). There was also a significant main effect of subscale type, F(3,8) =.04, p < 0.001, η p = 0.5. Scores on the Personal Distress subscale were significantly lower than scores on the remaining subscales. The interaction effect was not statistically significant, F(9,8) = 1.85, p = 0.71, η p = Discussion The results of this study showed that AN and ASD groups, in accordance with prof. Treasure s postulation that AN is a female form of autistic disorder, do not differ from each other but significantly differ from the HC groups when compared on autistic traits. However, we found the differences between these groups in levels of empathy, with the AN group achieving higher (as high as HC females) scores than the ASD group. Despite a wide range of studies comparing autistic and anorectic individuals on empathizing/systematizing (Frith and Happé 1994, Baron-Cohen 00, Lawson et al. 004, Baron-Cohen et al. 013), autistic traits (Hambrook et al. 008, Baron-Cohen et al. 001, Anckarsater et al. 01, Tchanturia et al. 015), and ToM (Oldershaw et al. 011, Baron-Cohen et al. 001, Harrison et al. 009, Fernández-Abascal et al. 013), there were no single studies that tested all of these traits simultaneously. On the other hand, some studies showed that autistic traits are crucial in cases of concomitant AN and ASD (Anckarsater et al. 01, Tchanturia et al. 013, Mandy and Tchanturia 015) reflecting the link between these two disorders. There are a few studies comparing three types of emotions valence from the RME test in AN (Tchanturia et al. 015), but there is the lack of studies compared 56 Clinical Neuropsychiatry (016) 13, 4/5

5 Similarities and differences between anorexia nervosa and autism spectrum disorders AN and ASD groups with additional tests measuring autistic traits. In the presented study, participants in all groups obtained the best emotion recognition in the case of neutral emotions. The ASD group exhibited overall lower performance, regardless of emotion type. Performance of the AN group was on the same level as performance of both comparison groups, and thus the hypothesis about AN having similar impairments of ToM as ASD was not support by our data. As we have shown, lower social functioning resulting from AN is not evident in all studied aspects as it is in ASD patients. It is instead visible only in areas associated with cognitive and attentional flexibility, communication, and general social competences, but not within the domain of sharing and recognizing emotions and mental states. The data obtained from this study may help to clarify the specific pattern of social impairments present in Anorexia Nervosa patients. We showed that AN patients are characterized by an extraordinarily high level of autistic traits that equaled that of the ASD group. On the other hand, normal levels of empathy and ToM indicate that some areas of social functioning are intact in this group. Such a pattern of results suggests that there are some similarities between AN and ASD groups when comparing them on different dimensions of social and emotional functioning, but these similarities only partly support the opinion that AN is a form of female autism. All presented above characteristics such as inability to taking information from global context of objects as well as the tendency to focus on details (Weak Central Coherence), impairments of reading the mental states of others (Theory of Mind deficits), poor set-shifting, lack of imagination are typical to both this disorders. The result of similar distortion of those traits allows to presume that Anorexia Nervosa individuals, especially females could present similar endophenotype to Autism Spectrum Disorder individuals. Therefore, due to presenting similar deficits, AN could pretend to be female version of ASD (e.g. Zücker et al. 007, Baron-Cohen 013). There are also several studies showed higher levels of Autistic Traits in Anorexia Nervosa patients in comparison to healthy population (Courty et al. 013, Harrison et al. 009, Treasure & Schmidt 013, Tchanturia et al. 013, Pooni et al. 01, Huke et al. 014). Interestingly is that both, eating disorders in ASD and autistic traits in AN are more common than in normal population (e.g. Rastam 008, Mandy and Tchanturia 015). Specific and abnormal eating as unusual eating preferences as desire to eat only one product or one type of food occur more frequently in ASD individuals (Rastam 008). Lower body weight that are present in ASD is associated rather with those pattern instead of (as it is specific in AN patient) extensive self-control (Bölte et al. 005). Autism Spectrum Disorders supposed to be a different disease than Anorexia Nervosa. On the other hand, all things considered that they have several similarities in many cognitive functions. Causes of this similarities are still not well established because of many neurobiological, physiological and psychological variables that have an influence on origination and persistence of impairments in cognitive and affective processes. Though this, providing many research is required to discover not only similar cognitive processes but also bases on neurobiological (and genetic) level to be able to explain the source of these similar impairments. Although results from the current study showed that the AN and ASD individuals have similar cognitive profile, it has much limitations. The first, there were mismatch in the clinical groups sex. ASD group was consisted of males, and in AN group were only females. There were not data of weight in all groups except AN group, and we had only the declarative measure about weight (ASD and HC comparisons groups), and not having psychical impairments in HC comparisons groups. Another limitation was the amount of participants in the clinical groups. Although this, the study was the first presenting comparisons within AN, ASD and HC groups in used tests and shed light to cognitive but not metacognitive similarities in those groups. On the other hand, the study from 015 (Mandy and Tchanturia 015) when social flexibility was tested in the eating disorder group describing the group of the 10 patients with ED and only three of them had the levels of autism traits pretended to lying on the autism spectrum. The past research as well as the current study did not show that the AN could be the autism-like disorder. The complexity of both disorders and occurring concomitant disorders make the diagnosis more difficult. Moreover, contradictions in the past studies and the possible differences in the social and cognitive functioning between groups that were tested across the studies (and results from the complexity of the AN and ASD). On the other side, showed similarities on the cognitive level may help not only to better understand both AN and ASD, but also creates more effective therapies. List of Abbreviation ASD Autism Spectrum Disorders AN Anorexia Nervosa HC males Healthy Comparison males HC females Healthy Comparison females ToM Theory of Mind EQ Empathy Quotient scale AQ Autism Quotient scale AQSC AQ Social Competences subscale AQAS AQ Attention Switching subscale AQFD AQ Focus on Details subscale AQCom AQ Communication subscale AQIm AQ Imagination subscale RME Reading the Mind in Eyes test IRI Interpersonal Reactivity Index scale IRIEC IRI Empatic Concern IRIPD IRI Personal Distress subscale IRIPT IRI Perspective Taking subscale IRIF IRI Fantasy subscale Acknowledgements We would like to sincerely thank Paweł Dobrowolski for the critical insight and the lexical correction of the manuscript. Ethics approval and consent to participate According to the Declaration of Helsinki, research obtained approval of Ethics of Scientific Research Committee from University of Social Sciences and Humanities. All participants were informed about anonymity of collected information and they approved Clinical Neuropsychiatry (016) 13, 4/5 57

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