Gender Differences in Symptom Presentation and Emotional Comorbidities in Higher Functioning Children with Autism

Background: Given the gender ratio of 4:1 for autism spectrum disorders, females tend to be underrepresented in research samples.  As such, little is known about the specific diagnostic and treatment needs of girls with autism. Gender differences in symptom expression and patterns of comorbidity have important implications for both diagnosis and intervention.
Objectives: To investigate the associations between gender, symptom presentation and emotional comorbidity in a sample of  High Functioning Children with Autism (HFA)  and a sample of gender-, age-, and IQ-matched typically developing children.
Methods: Preliminary results are reported on sixty-eight children (34 HFA (17 female); 34 comparison (17 female). Parents completed the Social Communication Questionnaire (SCQ), Autism Spectrum Screening Questionnaire (ASSQ) and Social Responsiveness Scale (SRS).  Additionally, each participant completed the Behavioral Assessment Scale for Children (BASC) self-report and the Autism Diagnostic Observational Schedule (ADOS).
Results: Preliminary analyses revealed an interaction between diagnostic group and gender on the SCQ total score, F(1,66) = 5.57, p = 0.02 and the ASSQ Total Score, F(1,68) = 4.92, p = 0.03.  Specifically, HFA males were reported as more symptomatic than HFA females, whereas gender was unrelated to symptom scores within the comparison sample. Moreover, analyses indicated a main effect of gender on SRS Total Score, F(1, 60) = 7.68, p = 0.08 as well as specific domains including Cognition, F(1, 60) = 4.60, p = 0.03, Communication, F(1, 60) = 6.03, p = 0.01, and Motivation, F(1, 60) = 9.16, p = 0.04. Regardless of diagnostic status, females were reported as more symptomatic on the SRS than males. Additionally, non-parametric analyses revealed that HFA males were scored as more symptomatic than HFA females on the ADOS Quality of Social Overtures, Quality of Social Response and Amount of Reciprocal Social Communication algorithm items. Further, analyses indicated a significant effect of gender on anxiety, F(1, 58) = 7.98, p = 0.07, and depression, F(1, 58) = 9.52, p = 0.03, on the BASC-SRP, such that females, regardless of diagnostic status, endorsed more internalizing problems than males. A series of regressions were run to examine the mediating role of anxiety on the relations between gender and SRS. Anxiety mediated the relationship between gender and the SRS motivation domain.
Conclusions: These data suggest that while still meeting diagnostic criteria, HFA females are reported as less impaired than HFA males when it comes to traditional diagnostic measures (SCQ, ASSQ, ADOS). However, when using a gender-normed diagnostic measure (SRS), females are reported as more impaired than males. These findings support the importance of combining traditional and gender-normed measures of symptoms to fully characterize the impairments of females with autism. For females, high levels of anxiety may contribute to low levels of social motivation. This suggests that clinicians should pay particular attention to internalizing problems in the diagnosis and treatment of females with HFA.