Transcript The Effects of Arachidonic Acid and Docosahexaenoic Acid Levels

The Effects of Arachidonic Acid
and Docosahexaenoic Acid Levels
on Children with Attention
Deficit/Hyperactivity Disorder
Ellen Ivity, B.A. (Psychology), MSc. Candidate,
Department of Medicine, University of Alberta
Dr. Tom Clandinin, Ph.D.
Professor of Nutrition, Departments of Agricultural, Food, and
Nutritional Science and Medicine
Outline
Description of AD/HD
Description of AA and DHA
Review of the Research
Rationale
Hypotheses
Inclusion Criteria
Methods
Analyses
Conclusions
Attention Deficit/Hyperactivity
Disorder
Most common childhood behavioural disorder
Affects all facets of an individual’s life
3 to 5 percent of children
Diagnosis
Usually made in children by the age of seven
Males are three times more likely to be
diagnosed with the disorder than females
Classified into three subtypes:
1. Primarily Inattentive (ADHD/I)
2. Primarily Hyperactive-Impulsive (ADHD/HI)
3. The Combined Type (ADHD/C)
Symptomology
Inattention: Difficulties sustaining attention
Makes careless mistakes
Difficulties planning, monitoring,
and completing tasks
Is disorganized, loses things, forgetful
Avoids tasks that require sustained
mental effort
Symptomology
Hyperactivity:
Cannot stay seated
Squirms and fidgets
Cannot play quietly, talks too much
Runs, jumps and climbs
at inappropriate times
Impulsivity:
Acts and speaks without thinking
Has difficulties taking turns
Cannot wait for things
Calls out answers before
the question is completed
Extreme mood swings
Aetiology
Multifactorial
Genetics, imbalances of neurotransmitters,
and diet are a few possible causative factors.
Males require three times more essential fatty
acids than females for normal development.
As Attention Deficit/Hyperactivity Disorder is
associated with low levels of essential fatty acids,
this may account for the higher prevalence of males
in this disorder’s population.
Treatment
Methylphenidate is the
most popular medication
used to treat AD/HD.
Two million children
take Ritalin around the
world.
The number of
prescriptions for the
drug doubles every two
years.
Treatment
The production of
Ritalin has increased by
almost five hundred
percent in the last five
years.
In 1996 alone,
consumers spent over
373 million dollars on
Methylphenidate.
Prognosis
Approximately half of children notice a considerable
decrease in hyperactivity as they grow older.
20% - 60% continue to be afflicted with significant
problems of inattention, distractibility, and impulsivity
throughout the span of their lives.
Arachidonic acid &
Docosahexaenoic acid
The Omega 3 (n-3) and Omega 6 (n-6) fatty acids have
been implicated in the aetiology of Attention
Deficit/Hyperactivity Disorder (AD/HD).
Necessary in ensuring the proper development and
functioning of virtually every organ system in the human
body.
They cannot be produced by the body, hence, they are
considered as essential and must be obtained from the diet.
Arachidonic acid &
Docosahexaenoic acid
More than one third of fatty acids in the brain
are of the omega 3 and omega 6 classes.
Arachidonic acid (AA), an omega 6 fatty acid,
and Docosahexaenoic acid (DHA), an omega 3
fatty acid, are the most prevalent.
They are the most abundant in the nervous system,
reproductive organs, grey matter of the brain,
and the retina.
Sources of AA
Animal meats
Liver
Kidney
Sources of DHA
Herring
Mackerel
Salmon
Tuna
Sardines
Modifying sources of dietary fat alters the
composition and metabolism of various tissues
in the body, as well as the composition of
structural lipids in membranes.
Therefore, to ensure healthy brain and body
functioning, sufficient dietary intakes of AA
and DHA are required.
Research suggests that low levels of AA and
DHA may contribute to the cognitive, behavioural,
and physical symptoms observed in children with
Attention Deficit/Hyperactivity Disorder.
Research Review
1966 - Caldwell and Churchill suggested a causal
relationship between essential fatty acid (EFA)
deficiency and negative behaviours.
Low brain levels of essential fatty acids may affect
neural functioning.
EFA deficiency leads to functional and structural
deficits. Impairments in the retina and brain are
observed, specifically in the frontal cortex, striatum,
and dopaminergic system.
Monkeys
Drs. Carlson and Neuringer, in 1999, observed
Lower n-3 levels in the brain and retina and abnormal
retinal function
EFA deficiency affects the temperament, motivation, and
sensation of monkeys, which in turn affects cognition.
Increased look duration times in a visual attention test
as compared to healthy controls
Research Review
In infants, longer look duration correlates positively
with poorer performance on later cognitive tests.
Look duration may be a measure of information
processing speed.
Look duration time may be a measure of ability to
shift attention or disengage from a stimulus, or a
measure of higher reactivity to visual stimuli.
Mice
In 2000, Carrie and colleagues found that
 Phospholipids in the frontal cortex are highly enriched
in fatty acids.
 Chronic ALA deficiency leads to significant reductions
of EFA in the frontal regions, as well as in the striatum.
 Supplementation of ALA increases EFA to control
levels in the striatum but not in the prefrontal cortex,
suggesting that chronic EFA deficiency can lead to
long-term impairments in prefrontal cortex functioning.
Mice
The same authors observed
• Learning impairments,
• Reduced exploratory activity,
• Increased anxiety in n-3 deficient mice.
EFA supplementation reverses the above deficits.
Hamazaki and colleagues, in 1999, observed that
Mice reared on omega-3 FA deficient diets for two
generations behaved differently and had different side
effects to behaviour-affecting medicines than controls.
Rats
A relationship between levels of brain fatty acids and
functioning of the dopaminergic system exists.
Dr. Zimmer and colleagues, in 1999, found
Decreased dopamine levels and Dopamine 2 (D2)
receptor binding in the prefrontal cortex but not in the
striatum.
Causes visual and behavioural problems.
Rats
Inadequate storage of dopamine has been implicated
in the aetiology of these problems.
During learning tasks, the dopamine system is stimulated.
Inadequate levels of this neurotransmitter may lead to
cognitive impairments, as the brain is unable to sustain
a satisfactory level of dopamine release.
Children
In 1995, Stevens and colleagues observed
1. significantly lower levels of AA, EPA, and DHA
in the plasma and blood cell lipids.
2. a higher number of behavioural problems using
the Conner’s Rating Scale.
3. higher incidences of behaviour problems, temper
tantrums, and sleep deficits.
Children
The same year, Mitchell et al. found
1. lower levels of AA and DHA,
2. significantly more language, reading, and learning
difficulties,
3. more visual and auditory deficits.
The above studies offer evidence that deficiencies in
AA and DHA may be associated with some of the
symptoms observed in ADHD.
Myelin
Drs. Jumpsen and Clandinin stated, in 1995, that
Memory is dependent on proper neuronal function.
Essential fatty acid deficiency may cause problems with
the myelination of neurons.
The myelin sheath insulates nerve impulses.
Amyelination or dysmyelination due to myelin lipid
deficiency or delays in its production have been shown
to lead to neurological disease.
Physical Symptoms
Many children with Attention Deficit/ Hyperactivity
Disorder have low levels of AA and DHA.
A significant number of these children exhibit
physical symptoms of essential fatty acid deficiency.
Physical Symptoms
Bonnie Kaplan and her colleagues, in 1997, found that
1. halitosis,
2. rhinitis,
3. headaches, and
4. night awakenings
were more common in children with AD/HD .
Sleep latency was also found to be affected in the
children with AD/HD.
Physical Symptoms
In 1995, Stevens et al. found that children with AD/HD
1. urinated more often,
2. had greater thirst, and
3. exhibited more dry skin
The above studies suggest that many children
with AD/HD exhibit physical symptoms of essential
fatty acid deficiency.
Rationale
Deficiencies in AA and DHA may contribute to the
impairments observed in children with AD/HD.
Many of these symptoms are alleviated with supplementation
of AA and DHA.
Therefore, identification of children deficient in AA and DHA
is important.
Lack of research on these two essential fatty acids and their
effects on developmental disorders such as AD/HD. This
project plans to increase that knowledge.
Hypotheses
Some children with AD/HD exhibit symptoms of
essential fatty acid deficiency. More specifically,
1. These children have low dietary intakes of
DHA and AA, as measured by a four-day diet
record.
2. These children have low DHA and AA levels in
the phospholipid fractions of their cell
membranes, as measured by blood and buccal
cell samples.
Hypotheses
3. These children exhibit physical symptoms
of essential fatty acid deficiency, such as
frequent urination and dry skin, as measured
by a medical symptom questionnaire.
Inclusion Criteria
 Participants: One hundred boys and girls from
psychology clinics in Edmonton
 Age Range:
6 to 8 years of age
 Diagnosis: AD/HD according to the DSM-IV,
with an absence of co-morbid disorders requiring
treatment.
Inclusion Criteria
 Medication: Can be on or off medication
prescribed to treat AD/HD.
Cannot be taking any other prescription medication.
Cannot be on any special diets or taking any regular
supplements.
Methods
1.
Four-day diet record of meat and fish intake.
2.
Medical symptom questionnaire
3.
Buccal swab
4.
Finger prick
Analyses
The blood samples and buccal swabs will be
analysed to determine each child’s endogenous
levels of AA and DHA.
The fatty acid levels will be compared to data
obtained from previous research on typical
children of a similar age range.
Analyses
The results of the present study will be
analysed to see if any relationships exist
between endogenous fatty acid levels, medical
symptom questionnaire results, and/or dietary
intakes.
Conclusions
Adequate dietary intakes of Arachidonic acid and
Docosahexaenoic acid are required for the healthy
development and functioning of cognitive systems.
AD/HD is the most prevalent behavioural disorder in
children. The disorder affects all facets of an
individual’s life.
The cognitive, behavioural, and physical impairments
found in AD/HD are associated with low levels of AA
and DHA.
Conclusions
Identification of children deficient in these two
fatty acids is important.
There is a lack of research on both AA and
DHA and their effects on developmental
disorders such as AD/HD. The goal of this
study is to increase that knowledge.
Ultimately, the goal is to develop healthier
alternatives to medication for the many individuals
who suffer from Attention Deficit/Hyperactivity Disorder.