Anxiety In People Diagnosed with Autism and Intellectual Disability: Recognition and Phenomenology

Background:

Anxiety seems to occur frequently in individuals with autism, but varying prevalence estimates indicate uncertainties in identifying anxiety, especially in those with intellectual disability (ID).

Objectives:  

The study explores the recognition of anxiety symptoms, and aims to provide suggestions for the assessment of anxiety in individuals with autism and ID. The main research question is whether physiological arousal, which was the assumption, was more easily recognized than the cognitive aspect of anxiety in these individuals. Moreover, in comparing assessment by checklist and reports on anxiety symptoms obtained in a comprehensive diagnostic process, the aim was twofold: 1) to explore whether assessment by a screening checklist is sufficient to identify the individuals with anxiety problems, and 2) to examine in more detail how anxiety is manifested in these individuals.

 Methods:

Two separate samples, a community sample (62 individuals with autism + ID) and a clinical sample (9 individuals with autism + ID + psychiatric disorders) were assessed with anxiety items and general adjustment problems items from a screening checklist, the Psychopathology of Autism Checklist, PAC. In addition, in the clinical sample checklist results were compared with clinical assessments.   

 Results:

The scores on the general anxiety items in the PAC, which are supposed to assess the cognitive aspect of anxiety, were higher than the scores on the specific items, which assess physiological arousal. The similar pattern was demonstrated in the total community sample, in the anxiety group (i.e. the group screened with anxiety problems), and in the clinical sample. Twenty-three participants (37.1 %) in the community sample were screened to have anxiety problems.

Comparison between clinical assessment and assessment by the PAC in the clinical sample revealed diverging reports in four participants. In the clinical anxiety assessment, anxiety symptoms were reported in all nine participants, but only seven of nine participants obtained an anxiety score above cut-off on the PAC.

The anxiety symptoms reported in the clinical assessment include 36 different symptoms and most of the symptoms described are typically anxiety symptoms, i.e. anxiety symptoms often described in individuals without autism. Only nine idiosyncratic symptoms were reported, i.e. unusual expressions of anxiety.

 Conclusions:

The results indicate that physiological arousal may not be as readily observable as assumed in individuals with autism and ID. The results also indicate that anxiety occurs frequently in this population, and support previous findings that the close association between anxiety and other psychiatric disorders also applies to individuals with autism and ID. Moreover, anxiety may be recognized in this group by similar symptoms as in individuals without autism, but the difficulties in recognizing signs of physiological arousal indicate the importance of increased clinical awareness toward such symptoms. To be able to identify individuals in need of further psychiatric examinations by using screening checklists, anxiety signs as well as signs of general adjustment problems probably have to be included. However, for diagnostic purposes and for monitoring treatment, individual anxiety assessment conducted in cooperation between professionals and care staff and family who know the individual well seems indicated.