CAN ADHD BE PREVENTED BY
by David Rabiner, Ph.D., Licensed Psychologist
Copyright (C) 1999
Almost all of the
work I have seen in helping children with ADHD focuses on providing effective
treatment after the disorder has been diagnosed. Studies on the possible
prevention of ADHD, in contrast, are few and far between. Is it possible
that early intervention in children showing signs of being at risk for
the development of ADHD could prevent the development of the condition
when they are older? This is an extremely interesting and important question.
A study that appeared in Israeli Journal of Psychiatry and Related Science
provides an interesting initial look at this question (Rappaport, G.C.,
Ornoy, A., & Tenenbaum, A. (1998). Is early intervention effective in
preventing ADHD? Israeli Journal of Psychiatry and Related Science, 35,
271-279). The authors of this study note that ADHD is usually not diagnosed
until after a child begins school, even though evidence of ADHD symptoms
is often present at a much earlier age. Clinicians are often reluctant
to diagnose ADHD in preschool age children - and rightly so, in my opinion
- because of the difficulty involved in differentiating between normal
and deviant behavior in children this young.
On the other hand, some studies have shown a significant continuity of
ADHD symptoms from a very early age. Thus, one research has reported that
33% of children who were hyperactive at age 3 were diagnosed as having
ADHD at age 11. The authors of the current study had found in prior work
that among 2-4 year old children who showed signs of inattention, hyperactivity,
and speech delay, approximately 80% were diagnosed as having ADHD upon
reaching school age. Based on these earlier results, the authors reasoned
that such symptoms in young children might serve as early signs of ADHD,
and wondered whether early intervention by non-pharmacologic methods might
be effective in reducing the number of children showing these early signs
who go on to develop ADHD.
In this study, the authors identified 77 children between the ages of
2-4.5 who were showing problems with inattention, and who showed evidence
of speech and/or motor delay. All of the children identified were offered
treatment, which consisted of occupational therapy and speech therapy.
These treatments were individually administered at least once a week over
a period of at least 6 months. The authors hypothesized that improving
children's speech and motor functioning would also enhance their attention
and concentration abilities, and that this would reduce the incidence
of ADHD in those children receiving treatment. About 60% of parents elected
to provide their children with the recommended treatment while about 40%
Children were followed up an average of 5.5 years later when they were
8-10 years old. Fifty-one of the original 77 children were able to be
contacted, and a comprehensive evaluation of ADHD was performed at this
time. Of the children who were evaluated for ADHD, 31 had received the
early speech and occupational therapy evaluation and 20 had not. Did the
rates of ADHD differ in these two groups?
Of the 21 children who had not received the early intervention, 10 (48%)
were diagnosed with ADHD at the follow up assessment. (These follow up
evaluations were done by examiners who were not aware of whether or not
the child had received prior treatment.) In contrast, only 33% of children
who had received the early Intervention were diagnosed with ADHD at this
time. These results are in the expected direction, but were not statistically
significant. This means that differences of this magnitude could have
occurred by chance reasons alone.
When looking at children according to whether or not there was a family
history of ADHD, however, the results are more striking. Every child who
was from a family where another member had ADHD and who did not receive
the intervention, was diagnosed with ADHD at follow up. In contrast, only
37% of children who had the same family history but who received the early
intervention developed ADHD. The differences between these rates was statistically
significant, meaning that they were unlikely to reflect chance factors
alone. When there was not any family history of ADHD, whether or not a
child received early intervention services was not related to whether
or not he/she developed ADHD.
These results need to be considered cautiously, as they were obtained
with a small sample of children and certainly require replication with
a larger sample. Even so, I think they are quite intriguing. What they
suggest is that for children who are showing early signs of ADHD, and
who have a family member who has this disorder, early intervention may
be effective in reducing the odds of their developing ADHD later on. Perhaps
other types of intervention, or similar interventions applied for a longer
time, might prove similarly helpful for children showing early signs of
ADHD but do not have a positive family history.
In terms of the practical application of these results, I think the most
important message is that when a young child is showing signs of difficulty,
efforts should be made to determine the best ways to address that difficulty.
I have been involved in many situations where a parent felt certain that
their child was not developing in ways that they felt comfortable with,
but were told that the child was too young to diagnose and would probably
just grow out of the trouble.
Although I agree that diagnosing a 2 year-old with ADHD is not appropriate,
that does not mean that treatment/assistance should not be provided to
a child that age who is showing problems in their development. The important
thing, I think, is to provide a young child with the assistance he or
she may need to help get their development back on a healthy trajectory.
When the difficulties really are interfering with their developing the
skills and abilities they need, then waiting until they "outgrow" them,
or not providing any assistance because they are too young to diagnose
with ADHD, does not seem like a particularly helpful position to take.