Intellectual Disability 237reasons, lower intelligence could well result in more anxiety, misery and
anger. In the case of disruptive behavioural disorders, possibility A is
supported by a fairly linear relationship with IQ. Within the normal IQ
range, lower IQ is associated with more disruptive behavioural even when
socio-economic background has been allowed for. The particularly high
rate of disruptive behaviour among children with intellectual disability
appears to be a continuation of this trend. It looks as though any cause
of lower IQ, whether organic, polygenic or social, increases the risk of
disruptive behavioural disorder.
There is little evidence supporting either of the other two possible
explanations for the link between intellectual disability and psychiatric
problems. The adverse social factors (such as lack of stimulation) that
contribute to low IQ are different from the adverse social factors (such
as harsh parenting) that increase psychiatric risk – arguing against possi-
bility C. Finally, although psychiatric problems may interfere with school
performance, they do not usually reduce measured IQ – arguing against
possibility D.
Treatment
Treating the psychiatric disorders of children and adolescents with intellec-
tual disability differs in emphasis but not in principle from treating similar
disorders in children and adolescents of average intelligence. Behavioural
treatment is particularly valuable in building up self-help skills and in
reducing undesirable behaviours such as self-injury, stereotypies and fre-
quent night waking. To be effective, behavioural therapy must be carefully
tailored to the individual. For self-injurious behaviour, for example, advice
to ignore a child during episodes of self-injury may be appropriate if the
child uses the behaviour primarily to attract extra attention. However,
it would only succeed in reinforcing the self-injurious behaviour if the
child primarily used the behaviour to discourage unwanted attention.
In addition to behavioural therapy, a wide range of other therapies can
be deployed, including family therapy, cognitive therapy and supportive
psychotherapy – depending on the nature of the problem and the age and
cognitive level of the individual.
The role of medication in the treatment of psychiatric problems associ-
ated with intellectual disability remains controversial. In the short term,
neuroleptics do reduce serious aggression and may therefore be useful in
an emergency. However, the benefits usually wear off quite rapidly. It is
then tempting to increase the dose to gain another temporary respite. Un-
less this temptation is resisted, the dose is likely to escalate progressively,
leaving the individual on high-dose, long-term neuroleptic medication
with all its attendant hazards (see Chapter 38). The pointlessness of
this long-term medication is often only evident when the medication is
finally withdrawn: aggression typically worsens for a while and then re-
turns to its previous level. As a rule, challenging behaviour requires social
and psychological management rather than pharmacological treatment.
With this reservation, medication can be useful at times. Moderate doses