Study: Dietary Supplementation With Fatty Acids...


Interesting study.

The Oxford-Durham Study: A Randomized, Controlled Trial of Dietary Supplementation With Fatty Acids in Children With Developmental Coordination Disorder
Alexandra J. Richardson and Paul Montgomery
Pediatrics 2005;115;1360-1366

The following excerpts from:

"ABSTRACT. Background. Developmental coordination
disorder (Developmental Coordination Disorder (DCD)) affects 5% of school-aged children.
In addition to the core deficits in motor function, this
condition is associated commonly with difficulties in
learning, behavior, and psychosocial adjustment that
persist into adulthood. Mounting evidence suggests that
a relative lack of certain polyunsaturated fatty acids may
contribute to related neurodevelopmental and psychiatric
disorders such as dyslexia and attention-deficit/hyperactivity
disorder. Given the current lack of effective,
evidence-based treatment options for Developmental Coordination Disorder (DCD), the use of
fatty acid supplements merits investigation....

To our knowledge, this is the first randomized,
controlled trial of this kind among children with
Developmental Coordination Disorder (DCD). Our hypothesis was that treatment for 3
months with a fatty acid supplement would lead to
significant improvements over placebo, as assessed
with changes in motor skills, reading and spelling
ages, and teacher ratings of behavioral and learning
difficulties usually associated with ADHD.

Results showed no effect of treatment on motor
skills but significant improvements in reading, spelling,
and behavior for active treatment versus placebo
during 3 months of treatment in parallel groups.

After a 1-way treatment crossover (placebo to active),
similar changes were seen in the placebo crossover
group, whereas children continuing with active
treatment maintained or improved their progress.
This study involved 117 children, between 5 and
12 years of age, from mainstream schools in 1 United
Kingdom county, all of whom met Developmental Coordination Disorder (DCD) criteria but
were otherwise normal and not receiving any other
treatment for their specific learning difficulties. Although
it seems unlikely that these children would
differ significantly from general population samples
in other developed countries, generalizability to
other age groups and cultures cannot be assumed.

The low rate of dropout and high rate of compliance
with treatment indicated that the researchers and
teaching staff members provided very strong motivation,
which might not be the case in other circumstances.
No adverse events were reported, and the
high compliance rate also suggests good acceptability
of fatty acid supplements.

The improvements in literacy skills and behavior
found here are consistent with other reports of benefits
from fatty acid supplementation among children
selected for dyslexia or ADHD,5,6 but it is noteworthy
that no group effect of treatment on motor
skills was apparent. The similarity in the effect sizes
for ADHD-related symptoms between this Developmental Coordination Disorder (DCD)
sample and one selected with standard criteria for
dyslexia5 suggests that these results may be more
widely generalizable. Although the focus of this investigation
was Developmental Coordination Disorder (DCD), the high level of comorbidity
typically found between these conditions and the
heterogeneity within each of them suggest that a
symptom-based approach may be more fruitful than
an exclusive focus on current diagnostic categories.
In this kind of population, delays in literacy development
usually increase over time, indicating the
value of early intervention. Children in the placebo
group fell even more behind with spelling during the
0- to 3-month parallel-group phase, although they
did show average progress in reading. In contrast,
children receiving active treatment made 3 times the
expected normal gain in reading age and twice the
normal gain in spelling age, bringing their average
scores toward normative values. In the follow-up
phase, they continued to make improvements above
what would be expected for chronologic age.

With global measures of teacher-rated behavior,
children receiving active treatment improved by
0.5 SD in the 0- to 3-month parallel-group phase,
with some additional improvements in the follow-up
phase. In the placebo group, no changes were observed
until the children crossed over to active treatment.

The first-line treatment for ADHD symptoms
in most developed countries is methylphenidate, for
which a recent meta-analysis21 found an overall effect
size of 0.78 with the Conners’ index but little or
no evidence of durability beyond 4 weeks of treatment.
By comparison, in this study the effect sizes
with this measure were 0.55 for the first 3 months
and 0.70 over 6 months for children receiving fatty
acid treatment throughout.

The problems faced by this kind of population are
enduring. Follow-up studies indicate that, without
specific intervention, children with Developmental Coordination Disorder (DCD) and ADHD
at 7 years of age have unusually poor academic,
social, and health outcomes in adolescence and
young adulthood.13,22,23 Studies with older populations
are therefore required, in addition to replication
of the current findings. Although our data suggest
that continuing treatment from 3 to 6 months
may produce additional benefits, issues of both durability
and maintenance of treatment effects also
require attention in future studies.

The optimal dosage and combination of fatty acids
are at present unknown. An -3/-6 ratio of 4:1 was
selected for this study on the basis of previous work
indicating benefits in dyslexia and ADHD,5,6 although
in this case the marine oil contained a higher
eicosapentaenoic acid/docosahexaenoic acid ratio.
Additional studies are needed to establish both the
optimal composition of fatty acid treatments and
dose-response relationships.

This study was a pragmatic one designed to investigate
the efficacy of fatty acid treatment and can
therefore shed no light on the possible mechanisms
at work. The findings do suggest, however, that fatty
acid supplements of this type may be a safe, tolerable,
effective treatment for improving academic
progress and behavior among children with Developmental Coordination Disorder (DCD)."