ASD & Changes in DSM-V - Western Autistic School

advertisement
ASD & Changes in DSM-5
Mark Stokes
© Dr Mark Stokes
When was the modern conception of Autism and
Asperger’s syndrome specified?
•
1797 – The Wild Boy of Aveyron emerged from forests, could not speak,
was clearly feral
•
1917 – Bolshevicks win revolution in Russia creating Soviet Union
•
1918 – West invades Soviet Union – War & hostilities persist until 1989
•
1926 – Soviet Union: Ewa Ssucharewa describes Schizoid Psychopathy
•
1920s – Leo Kanner & Hans Asperger study in Vienna
•
1939 – WWII commences in Europe
•
1941 – USA enters WWII against Germany
•
1943 – In USA Leo Kanner describes Autistic Psychopathology (Autism)
•
1944 – In Germany Hans Asperger describes Asperger’s Syndrome
•
1981 – Lorna Wing publishes seminal paper revealing similarity of
Asperger’s work to Kanner’s
•
1994 – DSM-IV published creating Asperger’s disorder as a separate
category from Autism
© Dr Mark Stokes
ASD: Historical Context
Autism conceptualised as Childhood Schizophrenia until 1979.
First edition of ICD did not include Autism.
•
•
•
•
•
•
•
1967
1977
1980
1987
1994
2000
2013 (May)
DSM-I:
DSM-II:
DSM-III:
DSM-III-R:
DSM-IV:
DSM-IV-TR:
DSM-5:
Autism as a form of schizophrenia
Autism as “Childhood Psychosis”
Infantile Autism
Autistic Disorder
Asperger’s Disorder
Mild changes in criteria
ASD www.dsm5.org
© Dr Mark Stokes
Diagnosed frequency
• Rate of
growth in
Diagnosis is
exponential
© Dr Mark Stokes
Diagnosed frequency
• Rate of growth
in Diagnosis is
exponential
• If trend
continues, by
2025 we will
diagnose 13% of
all children
A success for modern science:
At about 4PM on 23rd of October, 2037
100% of the population would be diagnosed with ASD
© Dr Mark Stokes
Diagnosed frequency
• Rate of growth
in Diagnosis is
exponential
Data curve with
girls added
A success for modern science:
At about 11PM on 4th of December, 2034
100% of the population would be diagnosed
• Girls are
underdiagnosed,
if we correct for
this, by 2025
20% of all
children would
be diagnosed as
having ASD
© Dr Mark Stokes
DSM-IV-TR diagnostic criteria
–
2 or more of Qualitative impairment in social interaction:
• Impairment in the use of multiple nonverbal behaviours
– (e.g.: eye-to-eye gaze, facial expression, body postures, and gestures to regulate social interaction)
• Failure to develop age appropriate peer relationships
• A lack of spontaneous seeking to share enjoyment, interests
• Lack of social or emotional reciprocity
–
1 or more of Qualitative impairments in communication:
• Delay or lack of spoken or alternative language
– (e.g.: gesture or mime)
• Where speech is adequate, impaired ability to initiate or sustain conversation
• Repetitive and stereotypic or idiosyncratic use of language
• Lack of varied, spontaneous imaginative or social imitative play
–
1 or more of Restricted repetitive and stereotyped patterns of behaviour, interests, and activities:
• Preoccupation with restricted patterns of interest that is abnormal either in intensity or focus
• Inflexible adherence to specific, non-functional routines or rituals
• Stereotypic and repetitive motor mannerisms
– (e.g.: hand or finger flapping or twisting, or complex whole-body movements)
• Persistent preoccupation with parts of objects
© Dr Mark Stokes
DSM-IV-TR diagnostic criteria
Asperger’s Syndrome
•
As for Autism, but:
–
No clinically significant delay in language
•
–
(e.g., single words by 2 years, communicative phrases by 3
years).
No clinically significant delay in cognitive development,
and curiosity about the environment
© Dr Mark Stokes
Reasons for the change
• Difficult to apply the criteria for the subtypes of PDD in a systematic way
• Most children diagnosed with AS meet criteria for Autistic Disorder (AD)
• Risk factors for AD & AS similar
“On the basis of the existing evidence, the committee concluded that
autistic & AS (along with the term PDDNOS) should be combined into
one category, called autistic spectrum disorder”.
• To control the exponential increase in cases
© Dr Mark Stokes
AS & Autism then; ASD now!
• No evidence to show that there is a separate AS and Autism condition
• Language delay differentiation
– No differences past early age
– Eisenmajer et al. 1998. JADD,28, 527. Delayed language onset as a predictor of clinical
symptoms in pervasive developmental disorders.
– Language profile between groups the same
– Manjiviona & Prior 1999. Autism, 3, 327. Neuropsychological Profiles of Children with Asperger
Syndrome and Autism.
– Manjiviona 1996. Neuropsychological profiles of children with Asperger syndrome and highfunctioning autism. Unpublished PhD thesis. La Trobe University.
• No cognitive skills delay differentiation
– Eisenmajer et al. 1996. J Am Acad Child Adolesc Psychiatry, 35, 1523. Comparison of clinical
symptoms in autism and Asperger's disorder.
– Barrett et al. 2004. Autism, 8, 61. Children on the borderlands of autism: differential
characteristics in social, imaginative, communicative and repetitive behaviour domains.
• Motor Skills differentiation (some slight, but not reliable)
– Manjiviona & Prior 1995. JADD, 25, 23 Comparison of Asperger syndrome and high-functioning
autistic children on a test of motor impairment.
– Rinehart 2009. Dev Med Child Neurol., 51, 2. Motor stereotypies in children with autism and
other developmental disorders.
© Dr Mark Stokes
AS & Autism then; ASD now!
• Treatment differentiation
– No evidence of any difference in treatment has any effect
– Vivanti et al. 2013 Australian Psychologist Towards the DSM-5 criteria for Autism: Clinical,
cultural, and research implications.
– No evidence as yet that teaching interventions are different by
diagnosis
– Dymond et al. 2013. Improving research knowledge and dissemination of school based
practices for children with autism. International Schools Based Education Research
(ISBER) Project, Victoria, Australia.
• Autism as a Spectrum better description
– Diagnosis as AS, HFA, Autism, PDD-NOS depends solely upon clinic
diagnosing
– Lord 2010 IX International Congress Autism Europe 10 October, 2010. Towards DSM-V:
New trends in diagnosis and classification in ASD
– Differences between children were only on individual social and
cognitive abilities & not diagnosis
– Prior et al. 1998 J Child Psychol Psychiatry, 39, 893. Are there subgroups within the
autistic spectrum? A cluster analysis of a group of children with autistic spectrum
disorders.
© Dr Mark Stokes
DSM-5 Autism Spectrum Disorder
A. Clinically significant, persistent deficits in social communication and
interactions.
1. Deficits in social-emotional reciprocity (i.e.: failure to initiate or respond to social
interactions)
2. Deficits in nonverbal and verbal communication used for social interaction;
3. Deficits in developing, maintaining and understanding relationships
Two of:
B. Restricted, repetitive patterns of behavior, interests, and activities
1. Stereotyped or repetitive motor movements, use of objects, or speech
2. Insistence of sameness, inflexible adherence to routines and ritualized patterns of
verbal or non-verbal behavior
3. Highly restricted, fixated interests of abnormal intensity or focus
4. Hypo- or hyper-reactivity to sensory stimuli, or unusual sensory behaviors
© Dr Mark Stokes
DSM-5 Autism Spectrum Disorder
C.
Symptoms must be present in early childhood (may manifest only when social
demands exceed capacities)
D. Symptoms must have a marked effect on ability to function
E. Severity must be specified: Level 1, 2, or 3
• Removal of separate Autism & Asperger’s categories to create Autism Spectrum
Disorder
• Criteria removed include:
– Lack of varied or imaginative play
– Language & cognitive delay
• Pre-existing diagnoses remain as diagnosed
• Recognition that many girls may go unrecognized
© Dr Mark Stokes
Severity
• Level 3
– Requires very substantial support
– Severe deficits in verbal and non-verbal social communication, very limited
initiation, minimal response to others(e.g. few words of intelligible speech)
• Level 2
– Requires substantial support
– Marked deficits in verbal and non-verbal social communication, limited
initiation, reduced or abnormal response to others (e.g. speaks a few
sentences)
• Level 1
– Requiring support
– Without support, has deficits in verbal and non-verbal social
communication, deficits in initiation and clear examples of unsuccessful
overtures and responses to others
© Dr Mark Stokes
New Diagnosis: Social Communication Disorder (SCD)
•
Impairment of pragmatics
•
Diagnosed based on difficulty in the social uses of verbal & nonverbal
communication in naturalistic contexts
•
Must affect the development of social relationships & discourse
comprehension and
•
Cannot be explained by low abilities in the domains of word structure &
grammar or general cognitive ability
•
Must first rule out ASD. By definition ASD encompasses pragmatic
communication problems
•
The low social communication abilities result in functional limitations in
effective communication, social participation, academic achievement or
occupational performance, alone or in any combination.
© Dr Janine Manjiviona
© Dr Mark Stokes
Advantages of DSM-5
1.
One spectrum of autistic disorders – ASD, defined purely by behaviours.
2.
No Differentiation among Autism, PDD-NOS, Asperger syndrome,
Childhood Disintegrative Disorder
3.
Blind to aetiology
No Differentiation within ASD among disorders by aetiology
4.
Simplified diagnostic approach
Many fewer ways a person may meet criteria in the two domains
5.
Social Communication domain recognises social function of
communication
© Dr Mark Stokes
Empirical findings
• Sensitivity
– The degree to which a test captures a trait
– A net that catches all fish
• Specificity
– The degree to which a test captures ONLY that
trait
– A net that catches fish and excludes Dolphins
© Dr Mark Stokes
Empirical findings
• Huerta et al. [including Cathy Lord]
• (2012; Am J Psychiatry, 169, 1056-1064) Application of DSM-5 Criteria
for Autism Spectrum Disorder to Three Samples of Children With
DSM-IV Diagnoses of Pervasive Developmental Disorders
• Compared how known cases and undiagnosed children met
DSM-5 criteria
– 4,453 children with Dx of PDD (2-17yo)
– 680 children without a Dx
• Using 1 symptom from each domain, and based on both
parent report & clinical measure found
– 91% sensitivity
– 63% specificity
© Dr Mark Stokes
Empirical findings
• McPartland et al. [including Fred Volkmar]
–
(2012, J Am Acad Child Adolesc Psychiatry, 51, 368-83) Sensitivity and specificity of proposed DSM-5
diagnostic criteria for autism spectrum disorder.
• Compared participants during a DSM-IV field trial
• 933 participants evaluated;
– 657 carried Dx of an ASD,
– 276 did not have a Dx of ASD
– for single criterion
• Average Specificity 72.2%
• Average Sensitivity 65.8%
– For multiple criteria
• Overall Specificity 72.2%
• Overall Sensitivity 76.0% to 25%
• Failure to meet the criterion
–
–
–
–
Only 60.6% of cases met DSM-5 criteria
More cases with lower IQ met criteria (69.7%) than cases with higher IQ (46%)
27% social communication
22% Restricted & Repetitive Behaviour
© Dr Mark Stokes
Download