Absence of a normal Cortisol Awakening Response (CAR) in adolescent males with Asperger Syndrome (AS)

SummaryIn addition to abnormalities in social and communication development, a ‘need for sameness’ and ‘resistance to change’ are features of autistic spectrum disorders first identified by Kanner in 1943. Our ability to react to change is modulated by the hypothalamic–pituitary–adrenal (HPA) axis, a feature of which is a dramatic increase in cortisol upon waking, the Cortisol Awakening Response (CAR). This study examined whether the CAR was evident in 20 adolescent males with Asperger Syndrome (AS) and 18 age-matched typically developing (TD) controls (aged 11–16). Whilst a significant CAR was evidenced in the TD control group, this was not the case for those with AS. A normal diurnal decrease in cortisol, however, was evident in both groups. The implication that individuals with AS may have an impaired response to change in their environment due to a refractory HPA axis is discussed.