Male to female sex ratios in autism are disparate (6.5:1 in autistic disorder, 12:1 in High Functioning Autism [HFA], and 6.8:1 across autism spectrum disorder [ASD]). Furthermore, females with HFA appear harder to identify or may present differently than males with HFA. In ASD, intelligence and adaptive behaviour are intricately linked. Intelligence appears to moderate sex differences, as intelligence decreases, sex differences dissipate. Whilst there have been limited results establishing sex differences in HFA, contrary results have also been reported. The reasons for these differences remain unexplained. It is possible that females with HFA are camouflaged.
Objectives:
The aim was to investigate whether the cognitive profile and adaptive functioning differed between females and males with HFA, and their typically developed (TD) peers. Our initial hypothesis was that the cognitive profiles and adaptive behaviours will differ between male and female adolescents with HFA. Secondly, the cognitive and adaptive behaviour profile differences between females and males with HFA will differ from the cognitive and adaptive behaviour profile differences of TD adolescents.
Methods:
Sixty four adolescent participants recruited from Independent, Catholic and Government secondary schools, and schools with programs for children with ASD around Melbourne and Geelong (Australia), were grouped by gender, age (12 to 18 years), and diagnostic status (HFA or TD), forming four groups with 16 participants each. The four groups consisted of: 1/ females with HFA, 2/ males with HFA, 2/ TD females, and 4/ TD males. Cognitive ability was measured by the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) or Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), executive functions by the Delis Kaplin Executive Function System (D-KEFS), and adaptive behaviour by the Vineland Adaptive Behaviour Scales-Second Edition (VABS-II). Developmental protocol and Autism Quotient questionnaire (AQ) findings, together with clinical judgement confirmed HFA diagnosis. Testing was conducted at Deakin University or in participant homes.
Results:
Hypothesis testing compared group differences through structural equation modeling. Preliminary findings support the prediction that adaptive functioning differs between males and females with HFA. This will be discussed.
Conclusions:
On the basis of preliminary analyses, this research appears to indicate differences in adaptive functioning between females and males with HFA.
See more of: Clinical Phenotype
See more of: Symptoms, Diagnosis & Phenotype