Creating
a Preliminary Neurobehavioral Profile of
Fetal
Alcohol Spectrum Disorders
ScienceDaily
(June 21, 2010) — A continuum of physical, mental, and behavioral
damage is caused by prenatal alcohol exposure (PAE) and is referred to by the
non-diagnostic term, fetal alcohol spectrum disorders (FASD). While the
identification of children along the continuum of FASD is complicated, it is
also necessary in order to assist more precise diagnoses and/or better treatment
options. A new study has constructed a preliminary neurobehavioral profile of
FASD using neuropsychological data from a multisite study, finding that
executive functioning and spatial processing are especially sensitive to alcohol
exposure. Results will be published
in the September 2010 issue of Alcoholism:
Clinical & Experimental Research and are currently available at
Early View.
"In
some cases, children with heavy PAE meet criteria for fetal alcohol syndrome
(FAS), which can be identified by trained professionals," explained Sarah
N. Mattson, a professor of psychology at San Diego State University and
corresponding author for the study. "However, the majority of children with
heavy PAE do not meet these criteria and cannot be identified by physical
features alone. The goal of this study was to determine a neurobehavioral
profile that could be used to help identify these children, even when the
physical features of alcohol exposure are absent."
"Having
a good sense of which behavioral manifestations of PAE are most consistent will
be of tremendous advantage in the diagnosis of FASD," added John H.
Hannigan, deputy director of the Merrill Palmer Skillman Institute for Child and
Family Development at Wayne State University in Detroit. "It is difficult
to diagnose children who do not show the facial features characteristic of FAS,
in part because neurobehavioral outcomes can be so variable, sometimes requiring
large numbers of tests to be done. The current study is important because it
boiled down 500+ measures to about 20 that converged mostly on two kinds of
outcomes."
Researchers
analyzed data taken from two sites of the Collaborative Initiative on Fetal
Alcohol Spectrum Disorders, an interdisciplinary study of FASD. Study
participants were between the ages of seven and 21 years of age at the time of
their neuropsychological assessments, and were divided into two groups: children
with heavy PAE (n=79) and unexposed children (n=60). The alcohol-exposed group
included children with (n=41) and without (n=38) FAS, which falls at the severe
end of the FASD spectrum. Out of 547 neuropsychological variables, 22 were
selected for analysis based on their ability to distinguish children with heavy
prenatal alcohol exposure from unexposed controls.
"Our
results told us that we could use some of our neuropsychological tests to
distinguish alcohol-exposed subjects from controls with a high degree of
accuracy," said Mattson. "When children with FAS and controls were
examined, 92 percent of the subjects were correctly classified. When we included
alcohol-exposed children without FAS and controls, 85 percent of the subjects
were classified. The measures that were most useful in this classification were
measures of executive function and spatial processing … which tells us that
although deficits are reported in a variety of neuropsychological domains, it
may be that some are more valuable that others in distinguishing alcohol-exposed
children from controls."
"'Executive
function' refers to abilities which allow a person to self-monitor or
self-direct what they should focus on, call to memory, and think about,"
explained Hannigan. "Poor executive function can impair the ability to plan
ahead, inhibit responding, or correct one's behavior in response to feedback.
Poor spatial processing means not only that FASD children may lose their way,
but these abilities may also be related through underlying brain processes to
problems with math, verbal abilities, and abstraction."
Both
Mattson and Hannigan noted the generalizing strength of these results -- having
found similar outcomes in children across diverse populations from San Diego,
California and Helsinki, Finland -- as well as the greater power of these
results versus IQ in distinguishing among the groups.
"Identification
of an FASD 'behavioral phenotype' or profile has been a prime goal of research
since FAS was first described in 1973," said Hannigan. "This profile
is important because having specific neurobehavioral outcomes that are most
reliably related to PAE not only aids diagnosis, but also can allow researchers
to better focus their time and resources on devising interventions."
Hannigan
added that the range and magnitude of neurobehavioral problems examined by this
study is a reminder that even modest prenatal alcohol consumption can have
life-long negative consequences on brain function and behavior in children, even
without leading to full FAS. "Thus, primary care providers have an
obligation to ask about their patients' drinking, to advise them to avoid
drinking during pregnancy, and to refer for appropriate intervention all women
who drink at risk levels and have difficulty stopping or limiting their
drinking," he said.
"While
this study is one important step in improving diagnosis of FASD, future steps
are also important," said Hannigan. "For example, testing of the
generated profile in diverse populations in order to compare how well it can
uniquely identify children with PAE compared to children with other
developmental disorders."
The
above story is reprinted (with editorial adaptations by ScienceDaily
staff) from materials provided by Alcoholism:
Clinical & Experimental Research, via EurekAlert!,
a service of AAAS.
Journal Reference:
- Sarah
N. Mattson, Scott C. Roesch, Åse Fagerlund, Ilona Autti-Rämö, Kenneth
Lyons Jones, Philip A. May, Colleen M. Adnams, Valentina Konovalova, Edward
P. Riley. Towards a Neurobehavioral Profile of Fetal Alcohol
Spectrum Disorders. Alcoholism
http://www.sciencedaily.com/releases/2010/06/100621173725.htm
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