Transcript ADHD: Our Advancing Knowledge and Implications for the

Aaron Tabacco, RN, BSN, LEND Faculty
Child Development and Rehabilitation Center
Oregon Health and Science University
Portland, Oregon
© 2009
Speaker Background
 Registered Nurse, BSN
 PhD Student at OHSU
 The Role of Fathers in Families with Children with ADHD
 Faculty Member
 LEND @ OHSU/CDRC
 University of Portland
 Family Nurse Case Manager – ADHD research study
 Family Care Coordination Team - CDRC
 Co-editor, Pediatric Home Care 3rd edition, a nursing
text
 Researcher, author, and frequent public speaker on
ADHD
 Parent of three sons with ADHD
Prevalence
 US studies report 3 – 7% of all children are affected
by ADHD. Has remained stable over 20 year period.
 International community has reported similar
prevalence. Netherlands - low with 2%, India highest – 30%
 In almost all cultures that report, the ratio of boys to
girls is remarkably similar, from 2 to 1 to 3 to 1
A Brief History of ADHD
 ‘Fidgety Phil’ – Germany
 Brain-Injured Child Syndrome
 Volitional Inhibition- George Still
 Min. Brain Damage- Post enceph
 Min. Brain Dysfunction
mid 1848
(late 1800’s)
(1902)
(1922)
(1930’s)
 Stimulant therapies start with success
 Hyperkinetic Reaction
(1950’s)
 Hyperactive Child Syndrome
(1960’s)
 ADD
(1980)
 ADHD, with and without hyperactivity
(1987)
Current Nomenclature:
Attention Deficit/Hyperactivity Disorder
(ADHD)
 Predominantly inattentive
 Inattention is predominant symptom. Activity
and impulsivity similar to other children,
“Daydreaming”, forgetting, misplacing,
disorganized, “not listening”
 Predominantly hyper-impulsive
 Inattentive symptoms may not be clinically
significant or under-recognized. Inattentive
symptoms may appear later
DSM-IV, 1994
Current Nomenclature cont…
 Combined type
 Most common type
 “mild” cases include those that meet criteria in
one type and just miss meeting enough criteria in
the other
DSM-IV, 1994
DSM IV Symptoms of
Hyperactivity/Impulsivity
 Fidgets or squirms
 Can’t stay seated when appropriate
 Runs about or climbs inappropriately
 Difficulty playing or engaging in leisure
activities (bounces from toy to toy)
 “On the go” or “Driven by a motor”
 Talks excessively
 Blurts out answers
 Difficulty waiting turn
 Interrupts others
DSM IV Symptoms of Inattention
 Fails to give close attention or makes
careless mistakes
 Difficulty sustaining attention
 Doesn’t seem to listen
 Doesn’t follow through
 Poor organization
 Avoids, dislikes, or reluctant to engage in
tasks requiring sustained attention
 Loses things
 Easily distracted
 Forgetful
Other causes of attention and
hyperactivity problems – NOT ADHD
• Sleep disorders
• Depression
• Bipolar disorder
• Learning disability
• Sensory problems
• Previous brain injury
or trauma
• Giftedness
• Language disorder
• Pervasive
developmental
disorder (autism)
 Mental retardation
 Migraines
 Seizures
 Anxiety
 Oppositional or


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
conduct disorders
Post traumatic stress
disorder
Substance abuse
Adjustment disorders
Abuse
ADHD and “Friends”
 Oppositional Defiant Disorder (40%)
 Language Disorder (30-35%)
 Anxiety and Depression (20-25%)
 Specific Learning Disability (15-25%)
 Mood disorders (15-20%)
 Conduct Disorder (20%)
 Substance use disorder (15%)
 Tics (15%)
ADHD and Lifespan Risks
 Risk Behaviors - UNTREATED
 200% to 300% more risk of substance abuse,
car accidents/infractions, pregnancy
 35% drop out of high school
 Up to 70% underachieve in SES
 250% more risk of incarceration
 Hypothesized decreased life-expectancy
Across the Lifespan
 80% of children given a
diagnosis of ADHD in early
school years will continue to
have symptoms in
adolescence
 Between 50% and 65%
school age children
diagnosed will have
symptoms into adulthood
and throughout their entire
lives
 This is a wide range
because different studies
have defined ADHD in
adults differently,
highlighting the need for
better adult criteria
Common Features – A
Developmental Disorder
 70% identified by caregivers by age 4
 Behaviors deviant from age-based standards
 Developmental deficit of self-control
 Range from 10% to 50%
 Average 30% (e.g., a 10 year old behaves like a 7
year old)
 Development does continue, but at a
greatly reduced rate compared with
unaffected peers
The Big Picture
Genetics make up
the largest
percentage of
ADHD causes = up
to 97% (80% avg.)
Toxins such as
tobacco, alcohol,
and lead make up 2
to 10% of cases
Brain Injuries 1 – 10%
Genetics
Toxin
Exposure
Brain
Injuries /
Other
The Unsatisfying ‘Old World’
 ADHD understood exclusively by 3 core
symptoms
 Inattention
 Impulsivity
 Hyperactivity
 Does not predict behavior or explain, only
describes
 Inconsistent from child to child
 Inadequate description of disorder
 Inattention? With 3 hours of nonstop video
games?
ADHD Knowledge:
A Recent Convergence 2000 – 2007
 Neuropsychology
 Genetics
 Biochemistry
 Medicine
 Pharmacology
 Radiology
 Nursing
Etiology – Why is this happening?
 Genetics
 IS NOT a chromosome-level flaw
 IS a gene-level expression (4 genes consistently
implicated)
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Highly heritable
About a dozen genes are implicated
Hundreds of studies
4 genes are of greatest interest / consistently
appearing in ADHD
 e.g. D4RD, Dopamine Transporter Gene
Physiology – What is happening?
 3 genes involve dopamine in the prefrontal
cortex
 1 specific problem with re-uptake
 2 specific problems with dopamine
receptors
 1 gene regulates norepinephrine in the
prefrontal cortex
 Metabolism of norepinephrine to dopamine
 Result: deficient frontal lobe neurotransmission
/ integration of limbic, motor, and other
systems
Development: How is it happening
 Longitudinal, high tech brain imaging study
comparing cortical maturation in children with
ADHD vs healthy controls (n= 223)
 Brain development pattern was identical to control,
but delayed on average by 3 years
 Prefrontal cortex focus of difference
 Primary Motor Cortex matured earlier by mean of 7
months
 Authors propose that the early motor cortex
maturation, paired with delayed higher-ordered
motor control may explain the “excessive and
poorly controlled motor activity cardinal to the
syndrome”.
Shaw, P. et al (2007). ADHD is characterized by a delay in
cortical maturation. PNAS. Vol. 4, No. 49
Russell Barkley, 2005:
ADHD and the Nature of Self Control
 The first well-developed theory of ADHD
 Aims to explain ADHD from the global knowledge
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of multiple disciplines
Describes with more clarity and consistency what
ADHD really appears to be
Allows for behavior prediction and testable
hypotheses
A vastly different approach than previous
thinking
Very new to the clinical world…only a handful of
clinicians are presently aware, let alone the
larger society
The Frontal Lobe: “Executive
Functions”
Frontal
Lobe
Perception
of Time
Inhibit
Responses
Working
Memory
Internalize
Speech
Self
Regulation
Perception of Time
 The perception of time passing is gained
by calibrating feelings of time with actual
time along a developmental trajectory
 Children with ADHD do not ‘feel’ the
passage of time as others
 3 min = 3 hours: all cues must be external
and concrete
 Can only feel now = ‘blindness to time’
Inhibiting Responses
 Frontal lobe is the essential
‘human’ determinant
 Evolutionary adaptation to
suppress fight or flight
 Allows us to utilize working
memory and experience to
guide present and future
behavior
 Developmental function of
frontal lobe
 Proficiency essential for
success in most human
environments
Working Memory
 The brain as a computer
 Frontal lobe houses ‘RAM’
 Long-term memory centers house all
experiences
 Impaired connections between working
and long term memory
 ‘Dial up connection vs High Speed’
 Limited access to past experience in the
moment, especially if in ‘stimulus crisis’
 Limited capacity of working memory
 Less information at one time
Internalizing Speech
 Work of Vygotski, Bronowski, Baddeley
 Speech develops externally and become
internal over time
 By age 4, most children begin the process
of internalizing speech
 By 5th grade most have mastered the task
 ADHD causes two problems
 Symptom of hyper-verbalism
 Maturation of external speech to internal, self
regulation
Self-Regulation
 The joint action of:
 Perceiving time
 Inhibiting distractions
 Remembering past experience and future
goals
 Internalized speech to guide self and behavior
 Regulating responses of the limbic system
 By virtue of disrupted frontal lobe
neurotransmission, executive functions are
impaired along a spectrum
The Book Report
“This report is due in 1 week” – Teacher
(Perception of Time)
“Come spend the weekend at my house and
we’ll have a sleep over!”
“Wait…I need to think about it for a moment…”
(Inhibit Responses)
“My book report is due in next week”
(Working Memory)
“If I go this weekend, I will not have enough
time for the book report…but I really want to
go!” –
(Internalizing Speech)
“Sorry, I can’t this weekend. How about next
weekend?”
(Self Control)
A Typical ADHD Profile
WISC-IV (Wechsler Intelligence Scale)
Verbal Comprehension
Perceptual Reasoning
Working Memory
Processing Speed
100
115
77
68
(Average)
(Average)
(Below)
(Below)
Stimulus Preferences for ADHD Brains
 Stimuli generated EXTERNALLY, providing
instantaneous feedback are relatively
unimpaired and “feel good”
 Imagine a child with paraplegia in a pool
[freedom]
 Video games, TV, Text Messaging
 Learning tasks requiring INTERNAL generation
and delayed feedback are highly impaired
due to decreased executive functions
 Homework, Reading (decoding,
comprehension, synthesis, working toward
a distant future goal)
In a nutshell…
ADHD, now more than ever, can be best
classified as:
 A Disability of Performance, not of Ability
 Kids do “know” but literally cannot “do” within
the context of their culture and expectations.
7 x 9 = 63
vs
“Don’t push people”
30 multiplication
problems in 1 minute
30 minutes of incidentfree recess
Situational Factors Affecting Executive Function
Symptoms
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Decreased Symptoms
One-to-one
Fathers (men)
Novelty
Frequent Feedback
Immediate
Consequences
Immediate Rewards
High Salience
Supervised
Earlier in the Day
Single Step Commands
External cues
Structured time
Consistency
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Increased Symptoms
Group Settings
Mothers (women)
Familiarity
Infrequent Feedback
Delayed
Consequences
Delayed Rewards
Low Salience
Unsupervised
Later in the Day
Multi-step Commands
Internal cues
Unstructured time
Change/Transition
ADHD focused Interventions with at
least some scientific evidence
 Medication
 Behavior
Modification
 Green Outdoor
Spaces
 Physical Activity
 Yoga
 Massage
 1 to 1 learning
 Token reward systems
(until about 10 years
old)
 Time out for behaviors
 Breathing and pulse
monitoring
Intervention: The MTA Study
 Multimodal Treatment Study of Children with
ADHD (MTA).
 First extensive, longitudinal study of its kind.
 Evaluated 579 children and continues to publish
data.
 4 groups
 Expert medication management
 Expert behavioral modification
 Combined
 Community Care (of which 2/3 took medications)
Jenson, et. al. (2007). Three year follow-up of the NIMH MTA study. Journal of
the American Academy of Child and Adolescent Psychiatry 46(8): 989-1002.
Summary
 ADHD is an organic brain difference most often
associated with genetics
 The location of these differences is the frontal lobe
 The difference is found in how effective dopamine
utility is in this region
 The frontal lobe is home to executive functions
 ADHD is a deficit of executive functions that impair
the ability of a child or adult to self-organize (selfcontrol).
Selected References / Resources
Taking Charge of ADHD: The Complete,
Authoritative Guide. Russell Barkley, 2000 (revised
2005)
ADHD and the Nature of Self-Control. Russell
Barkley, 2005
The ADHD Book of Lists: A Practical Guide for
Helping Children and Teens with Attention Deficit
Disorder. By Sandra Rief, 2003
Aaron’s contact information: [email protected]