Wednesday, 18 July 2012

Anxious children and autism traits?

I'm always been quite intrigued by studies examining the various behaviours linked to autism presenting in other conditions not necessarily linked to autism as a discrete entity. The various studies done on eating disorders* spring to mind as quite a good example.

This type of research - when it shows some positive correlation - kinda reiterates that when we talk about autism, we aren't so much talking about a single homogeneous condition, but perhaps rather a range of conditions which share some common behavioural characteristics summed up by the diagnostic label autism. I suppose its a bit like calling fizzy drinks (soda) and summer fruits 'sweet' but also realising that soda and fruit are quite different things outside of their sweet taste (if that makes any sense).

With this in mind, the publication of an interesting paper by Francisca van Steensel and colleagues** (full-text) on the presence of autistic traits in children with various anxiety disorders is quite an interesting read. The paper is open-access and suggests that whilst not necessarily fulfilling all the criteria for autism or the autism spectrum, children diagnosed with various anxiety-related conditions do seem to present more frequently with autism traits as described by their previous developmental history and current behaviour. There is another paper from the same authors*** which might also be relevant but I'm going to leave that for this post.

A short summary:

  • Parental interviews made on behalf of 42 children (mean age 12 years) diagnosed with one or more anxiety disorder were compared with interviews for 42 asymptomatic control children (mean age 11 years) based on the Autism Diagnostic Interview-Revised (ADI-R) and Children’s Social Behavioral Questionnaire (CSBQ) probing offspring early and current autism traits respectively.
  • Results: children with anxiety related disorders were reported to show/have shown an increased number of autism related behaviours compared with controls. 
  • Based on the ADI-R algorithm scores for the triad of core autism domains, over a third of children with an anxiety disorder surpassed one or more cutoff points for the presentation of autism-like behaviours during their developmental history. This was compared with none of the control group. Indeed, one child in the anxiety group surpassed thresholds on all 3 domains. Statistically speaking, the anxiety group scored significantly higher across all autism domains than the control group.
  • Based on CSBQ scores, the anxiety group also presented with a greater number of current autism-like behaviours than the control group. Again, nearly a third of children with anxiety related conditions "had scores that fell in the ASD range".
  • Interestingly, when looking at current anxiety symptoms based on the Screen for Child Anxiety Related Emotional Disorders (SCARED-71), several types of anxiety disorder correlated with scores of particularly current autism-like traits including panic disorder, generalised anxiety disorder, social anxiety disorder and separation anxiety disorder (all significant at p equal or less than 0.01).

I don't want to make too much out of this current paper bearing in mind the small participant group included. That being said however, this is not the first time that anxiety disorders have been looked at with autism traits in mind (see here).

Aside from important considerations such as (a) screening for autism in children with anxiety disorder brought about by this kind of research, assuming good validity of the instruments used, and not 'over-screening' and (b) the possibility of shared biochemistry, genes, etc., I started to wonder about what these results might mean for people with an autism spectrum condition. So for example, do the results work in reverse, and those with autism are perhaps more prone to an anxiety disorder? Certainly I don't think I can stress enough the effects that anxiety seems to have on many people with autism. In some cases dare I suggest that it is one of the most debilitating aspects to autism. The question is whether such issues merit a separate diagnosis of anxiety disorder and whether for example, managing the anxiety might have knock-on effects to other more core presentation?

On a final note, I couldn't help but raise a smile at the results presented by Pobbe and colleagues**** (full-text) on anxiety measurement in the Dangermouse that is the BTBR mouse model of autism. Not specifically relevant to the latest work but interesting insofar as the potential usefulness of the BTBR model.

Now, clear some space, break out the air guitar and let Bryan tell you all about his summer of '69.


* Coombs E. et al. An investigation into the relationship between eating disorder psychopathology and autistic symptomatology in a non-clinical sample. The British Journal of Clinical Psychology. 2011; 50: 326-338.

** van Steensel. et alAutism spectrum traits in children with anxiety disorders. JADD. June 2012.
DOI: 10.1007/s10803-012-1575-z

*** van Steensel FJ. et al.  Anxiety and quality of life: clinically anxious children with and without autism spectrum disorders compared. Journal of Clinical Child & Adolescent Psychology. July 2012.

**** Pobbe RL. et al. General and social anxiety in the BTBR T+ tf/J mouse strain. Behavioral Brain Research. 2011; 216: 446-451.

---------- van Steensel FJ, Bögels SM, & Wood JJ (2012). Autism Spectrum Traits in Children with Anxiety Disorders. Journal of autism and developmental disorders PMID: 22733297