1. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
Dr Elspeth Webb
Attention deficit hyperactivity disorder
ADHD

2. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 A condition comprising a degree of impulsivity & hyperactivity and/or
inattention to a point that is disruptive and inappropriate for developmental
level
 Pervasive & present for at least 6 months
 Two sub types: Inattentive and Hyperactive/impulsive
 Hyperactive/impulsive subtype also referred to as hyperactivity or
hyperkinetic disorder
But what is “inappropriate”?
A condition that is, in part, socially constructed.
Definitions: ADHD (DSM-IV TR)

3. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 1/10
 1/20
 1/50
 1/100
 1/200
Have a guess
Prevalence: – how common is it?

4. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 UK/USA/Australia/Scandinavia
• 5% for total (mixed or just hyperactive/impulsive or just inattentive)
• About 3% for hyperactivity ( i.e. mixed or just hyperactive impulsive
• 1% for mixed ICD10 (hyperactive & inattentive)
Politics: Administrative vs. real prevalence
USA : administrative prevalence greater than real - 10% of children on
medication for ADHD (Driven by litigation)
UK: real prevalence more than administrative – about 1% UK children
between 6 and 12 yrs are medicated (see http://www.ncbi.nlm.nih.gov/pubmed/22712630 )
Prevalence

5. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
Problems with :
Attention
Executive function
Neuro-psychological basis

6. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 detecting a stimulus
 encoding or processing information
 sustaining attention to relevant stimulus whilst
filtering out others
 shifting attention when appropriate
 inhibiting involuntary shifting (distractibility)
 organising a response to incoming information
Attention

7. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Studies suggest that the attentional problem is not at the level of
“going in”, but at the level of stimuli processing
 So children with ADHD do not have difficulties with receiving
information, but with subsequent processing and selection of
appropriate response
 i.e. it’s not that they don’t pay attention, but they act as if they
don’t pay attention, because they do not respond appropriately.
Attention in ADHD

8. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 A set of brain functions unique to humans, concerned with self regulation,
sequencing of behaviour, flexibility, response inhibition, planning and
organisation of behaviour
 Allows us to think about ourselves, what may happen in the future, and how
we can influence it. For example, these allow us to control impulses, because
we think about and consider what will happen if we do x or y. A child with
ADHD has already done x or y before the considering has started to process.
As children with ADHD get older and enter adolescence these are the areas of
function in which they get more different from their peers, precisely when we
start to ask more of them in these areas
Executive function

9. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Some diseases are “all-or-nothing”, e.g. influenza
 Others are “dimensional” in that the disorder or disease fades into normality
ADHD “normal”
For children on the cusp, it is difficult to distinguish disorder from personality.
To some extent it is a socially constructed diagnosis which is a disorder “here and
now” because it is hard to accept that 5% of all children are “abnormal”
ADHD as a dimensional disorder

10. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Linked
 Co-ordination problems
 Speech and language disorder
 Autistic spectrum
 Tourette syndrome
 Coincidental
 Hearing impairment
 Pseudo link
 Oppositional/defiant disorder and Conduct disorder
Co-morbidity/overlap

11. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Any intellectual activity is much more difficult for these children
both in getting started and in sustaining that activity
 They have to put in far more effort for any particular task
compared to their peers – everything is at least twice as hard
 This is very tiring
 They will therefore do anything to avoid intellectual effort
because it is so hard
Effort avoidance

12. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Genotype – our genetic inheritance and makeup – what our DNA says, which
genes we carry
 Phenotype – how our genotype is expressed . E.g. gene for cystic fibrosis results
in a phenotype that involves chest infections, digestive problems, infertility in
males. Genes for ADHD result in ADHD phenotype
 Phenocopy. – when another set of factors, usually environmental, result in a set
of signs symptoms and behaviours very similar to a genetic phenotype. Most
famous example – Romanian orphans and autism
 ADHD phenocopies – violence, abuse, and anxiety
Phenocopy of ADHD

13. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 The infant human brain at birth is very immature in comparison to other mammals
 ++ growth, development, cellular interconnections and cell culling in the first year
or two
 Direction and pattern of these processes is partly genetically, partly
environmentally driven
 Our children’s brains are sculpted irreversibly by their early (and perhaps even
prenatal) life experiences
 Children exposed to violence are hard wired to be anxious, distractible, highly
aroused in situations of conflict, and impulsively aggressive – this is largely
irreversible
Impact of early violence on brain
development

14. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Children living with violence are anxious, highly aroused, and have
raised cortisone
 Although for older children this does not have the same long term
impact on brain structure, fearful highly aroused children are:
 distractible/inattentive/overactive/impulsive
 How? - Weinstein et al, 2000:
 difficulty concentrating caused by re-experiencing trauma (PTSD)
 hyperactivity caused by hyper-vigilance
Impact of current violence on behaviour

15. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
 Higher prevalence of violence in low income families,
including domestic abuse (DA) and child abuse
Poverty associated with other risk factors for “ADHD”
 LBW and prematurity
 Intrauterine exposure to illegal drugs and alcohol (itself
strongly linked to DA)
Demography of violence

16. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
Aetiology:- what causes it?
Genes Exposure to
violence in
infancy
Teratogens
(esp alcohol) Prematurity/low birth weightPrematurity/low birth weight
Some of these factors are linked e.g. violence, Low birth weight, and foetal
alcohol exposure.
ADHD phenocopy

17. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
treatment
• Medication
AND
• Psychological approaches
Should depend on cause but doesn’t.
Evidence base not addressed heterogeneity
17

18. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
“….programmes on television in the UK exploring ADHD ……..ignored
children’s rights in that they were exploitive, contravened a child’s right to
privacy, and were certainly not in the best interests of the children involved.
They provided inaccurate presentations of ADHD with most of the
cases presented being conduct disordered children in very disadvantaged
circumstances. ….(The programmes) had a focus on these children not as in
distress, but as ….. bad. ”
Webb E. Health services: who are the best advocates for children?
Archives of Disease in Childhood 2002;87:175-177
ADHD & the Media

19. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
-a badly behaved,
impulsively aggressive,
morally deficient child
ADHD media stereotype
But children with ADHD can
be impulsively anything:-
brave, empathetic, witty,
cautious, clever, unkind,
generous, reserved,
oppositional, adventurous,
imaginative, energetic,
creative, destructive, etc..
Don’t stereotype or you
will miss cases
Don’t confuse personality
with disorder

20. Attention deficit hyperactivity disorder – ADHDAttention deficit hyperactivity disorder – ADHD
Summary
 ADHD is common, but under-diagnosed in the UK
 Affected children form a highly heterogeneous population: each
child with ADHD requires a tailored strategy depending on context
 Stimulants are effective in management (but they are not
everything)
 The severity of ADHD, and adult outcomes, are strongly affected by
how a child is treated by the adults in his/her life
Further reading (for those interested ) Webb E. Arch Dis Child doi:10.1136/archdischild-2012-
303578 Poverty, maltreatment and attention deficit hyperactivity disorder
see http://adc.bmj.com/content/early/2013/04/04/archdischild-2012-303578.full