The causes of autism spectrum disorders

Dear Sir,

I am concerned that Professor Szatmari’s editorial ‘The causes of autism
spectrum disorder’ is misleading in that it suggests more certainty about
the existence of an autism spectrum and about causes of autism that is
currently warranted.

In fact there remains considerable debate about the validity and
usefulness of a broad definition of autism (Volkmar and Klin, 2000).
Autism and Asperger’s syndrome, the main contenders for inclusion are
distinct conditions and although they share common features, namely
difficulties in social relatedness and obsessiveness, they can be
distinguished in regard to these. In autism, children are socially
withdrawn, while in Asperger’s syndrome they usually desire social contact
but cannot negotiate social rules. Furthermore in autism, which unlike
Asperger’s syndrome is frequently associated with mental retardation,
obsessiveness commonly revolves around routine behaviours and physical
objects while those with Asperger’s syndrome frequently display
idiosyncratic and often highly intellectual interests. The distinction
between autism and Asperger’s syndrome is comparable to that between
schizophrenia and schizoid personality disorder. Like autism and
Asperger’s syndrome they share common features and genetic loading,
however from a clinical point of view their distinction is crucial. The
danger of confusing Asperger’s syndrome with autism in a broad definition
is that not only that it might hamper research but that it risks over
diagnosis. This is an increasing problem in child psychiatry where
worried parents of troubled children increasingly demand diagnostic
certainty at the risk of error.

Professor Szatmari’s categorical statement that autism is a neuro-
psychiatric disorder is not only misleading but risks playing into this
latter problem. Although neurological problems have a bearing on autism,
the relationship remains obscure and the implied claim that autism results
from a primary neurological disorder is based on slim evidence. A strong
genetic link does not necessary imply neurological damage. Although
Professor Szatmari acknowledges environmental influences, he makes no
references to the social and emotional environment in which children are
raised. Although there is considerable evidence to support the importance
of these influences on children’s psychological and brain development, he
does not consider that these may play a part in the development of autism.
In fact there is evidence for the role of these factors in autism from the
studies of Romanian adoptees. (Rutter et al, 1999)

Professor Szatmari believes that research findings that support
organic causation help temper parental guilt when children have these
conditions. From a clinical point of view, it is my experience that
helping parents understand and come to terms with their unwarranted
feelings of blame about having children with these disorders is more
productive than trying to allay their anxiety with premature certainty
about causation.

References

1. Rutter, M et al. Quasi-autistic patterns following severe early
global privation in Journal of Child Psychology and Psychiatry. 40, 537 –
549. (1999) Cambridge University Press.

2. Volkmar, F. R. and Klin, A. Diagnostic Issues in Asperger’s syndrome
in Klin, A and Volkmar, F. R. and Sparrow, S. S. (2000) Asperger’s
syndrome. New York. London – The Guildford Press..

Dr. David Simpson

Consultant Child & Adolescent Psychiatrist
Tavistock Clinic,
120 Belsize Lane,
London NW3 5BA

dsimpson@tavi-port.nhs.uk

Competing interests:  
None declared