Early Indicators of Autism Spectrum Disorders

Download Report

Transcript Early Indicators of Autism Spectrum Disorders

Early Indicators of
Autism Spectrum
Disorders
Donald Oswald, PhD
Professor, Department of Psychiatry
Virginia Commonwealth University
Autistic Disorder – DSM-IV
• Key Characteristics:
– Qualitative impairment in social interaction
– Qualitative impairment in communication
– Restricted repetitive and stereotyped
patterns of behavior, interests, and activities
– Differences present prior to three years
Multisystem Developmental
Disorder – DC:0-3R
• Can be applied to children under two years of
age
• Features are descriptive, not criterion-based
• Does not require the range of relationship and
communication difficulties seen in Autistic
Disorder
• Used as alternative to PDD-NOS in children
under two years
» ZERO TO THREE. (2005). Diagnostic classification of
mental health and developmental disorders of infancy
and early childhood: Revised edition (DC:0-3R).
Washington, DC: ZERO TO THREE Press.
Multisystem Developmental
Disorder – DC:0-3R
• Significant impairment in the ability to engage
in an emotional and social relationship with a
primary caregiver (e.g., the child may appear
avoidant or aimless but may evidence subtle,
emergent forms of relating or relate quite
warmly intermittently).
• Significant impairment in forming, maintaining,
and/or developing preverbal gestural
communication or verbal and nonverbal
symbolic communication
Multisystem Developmental
Disorder – DC:0-3R
• Significant dysfunction in the processing
of visual, auditory, tactile, proprioceptive,
and vestibular sensations, including
hyperreactivity and hyporeactivity to
sensory input.
• Significant dysfunction in motor planning
(sequencing movements).
Etiology
• ASDs are
– Biologically based neurodevelopmental
disorders
– Highly heritable (recurrence risk is about 5 6 percent when there is an older sibling with
an ASD)
– Not caused by emotionally distant parenting
Etiology
– Sometimes associated with a medical
condition or known syndrome
•
•
•
•
•
•
Fragile X
Tuberous Sclerosis
Phenylketonuria
Fetal alcohol syndrome
Angelman syndrome
Rett syndrome
Prevalence
• “. . . the best estimate of current prevalence of
ASDs in Europe and North America is
approximately 6 per 1000”
» Johnson et al., 2007
• Prevalence by type:
– Autistic Disorder - 2.2 per 1000
– Asperger’s Disorder - 1.0 per 1000
– PDD-NOS - 3.3 per 1000
» Fombonne et al., 2006
Age at identification
• “the age at which a child was first identified by
a health, education, or other community
service provider as having an ASD. . .”
– a clinical diagnosis noted in an abstracted
evaluation
– eligibility for special education services under an
ASD category
– an International Classification of Diseases, 9th
Edition, code for an ASD
» Shattuck, P.T. et al., (2009). Timing of identification
among children with an autism spectrum disorder:
Findings from a population-based surveillance study.
Journal of the American Academy of Child and
Adolescent Psychiatry, 48, 474-483
Age at identification
•
• Entire sample
• Sex*
– Boys
– Girls
Median Age (yrs)
5.7
5.6
6.1
• IQ*
– >70
• Boys
• Girls
6.5
7.1
– <70
• Boys
• Girls
5.1
5.5
Developmental Screening
• Further evaluation is warranted if:
– Does not babble or coo by 12 months
– Does not gesture (point, wave, grasp) by 12
months
– Does not say single words by 16 months
– Does not say two-word phrases on his or her
own by 24 months
– Has any loss of any language or social skill at
any age.
– National Institute of Child Health and Human
Development (NICHD)
Screening and Early
Identification
• AAP Recommended Surveillance and
Screening Algorithm
– Evaluate risk factors:
•
•
•
•
Is there a sibling with autism spectrum disorders?
Are parents concerned?
Are other caregivers concerned?
Is physician concerned?
– If at least two risk factors present and child is at
least 18 months old, administer ASD specific
screening tool.
» Johnson et al., 2007
Screening and Early
Identification
• AAP Recommended Surveillance and
Screening Algorithm
– Regardless of risk factors, administer ASD
specific screening tool at both the 18 month
and 24 month visits.
» Johnson et al., 2007
Screening Instruments for
ASD
• Modified Checklist for Autism in Toddlers
• Social Communication Questionnaire
• These are parent-report instruments for
screening purposes only (not diagnosis)
Modified Checklist for Autism in Toddlers
(M-CHAT)
• M-CHAT
– Expanded American version of the original CHAT
– 23 questions using the original nine from the CHAT as its basis.
– Goal: to improve the sensitivity of the CHAT and position it better
for an American audience.
• Appropriate for children 18 - 24 months of age
• Yes/no answers convert to pass/fail responses.
• Child fails the checklist
– when 2 or more critical items are failed
– OR when any three items are failed.
• Available at www.firstsigns.org/
Robins, D., Fein, D., Barton, M., & Green, J. (2001
M-CHAT critical items
2. Does your child take an interest in other children? (No)
7. Does your child ever use his/her index finger to point, to indicate interest
in something? (No)
9. Does your child ever bring objects over to you (parent) to show you
something? (No)
13. Does your child imitate you? (e.g., you make a face-will your child
imitate it?) (No)
14. Does your child respond to his/her name when you call? (No)
15. If you point at a toy across the room, does your child look at it? (No)
Social Communication
Questionnaire
• A parent report screening measure for
autism spectrum disorders (ASDs)
• Based on the Autism Diagnostic
Interview-Revised (ADI-R).
• Use evaluated in an autism specialty
clinic and a general preschool
developmental clinic
» EAVES, WINGERT, HO, & MICKELSON, 2006
The Social Communication
Questionnaire
– 40 items, Yes/No format
– 10 minutes to complete
– Appropriate for individuals whose CA is at least 4
years (possibly CA at least 2 years) and whose MA
is at least 2 years
– Current and Lifetime forms; Lifetime generally used
for diagnostic screening
– Lifetime score of 15 or greater indicates possible
ASD, need for comprehensive evaluation
Social Communication
Questionnaire
• Overall sensitivity was .71, the same for both clinics
• Specificity was better for the preschool clinic (.62) than
for the autism clinic (.53) reflecting fewer falsepositives in the former.
• The ‘‘hit rate’’ was 65% with 28% of the children with
autism missed by the SCQ at a cutoff score of 15
(false negatives) and 38% of the nonautistic
misidentified as having an ASD (false-positives).
» EAVES, WINGERT, HO, & MICKELSON, 2006
Screening Follow-up
• Refer for diagnostic evaluation
– Developmental pediatrician
– Specialty clinic
• If developmental delays present, refer for
evaluation for Early Intervention services
while awaiting diagnostic clarification
Practitioner Review: Diagnosis of autism
spectrum disorder in 2- and 3-year-old children
• Multidisciplinary diagnostic assessment
– detailed information on developmental history
– parents' descriptions of the everyday behaviour and
activities of the child
– direct assessment of the child's social interaction
style, including where possible with age peers
– formal assessment of communicative, intellectual
and adaptive function
» Charman, T. & Baird, G. (2002). JOURNAL OF CHILD
PSYCHOLOGY AND PSYCHIATRY, 43, 289
Practitioner Review (cont.)
• Clinical assessments need to concentrate on
early non-verbal social communication
behaviours that characterise children with ASD
from the second year of life
–
–
–
–
–
social orienting
joint attention
Imitation
play
reciprocal affective behaviour.
Practitioner Review (cont.)
• The particular pattern of symptoms in a 2year-old with ASD may differ from that seen at
the more prototypic age of 4 or 5 years.
– e.g., overt repetitive and stereotyped behaviours
may be less notable, although where these are
seen alongside the social and communicative
impairments they are highly indicative of ASD.
Practitioner Review (cont.)
• The use of standardised assessment
instruments and the strict application of the
DSM and ICD diagnostic criteria need to be
employed with caution, as an expert clinical
view has been shown to be more accurate.
• An important aspect of early diagnostic
consultation is an open and straightforward
approach to the negotiation of the diagnostic
view with parents over time.
Autism Diagnostic Observation
Schedule - Generic (ADOS-G)
• Developed by Catherine
Lord, Michael Rutter,
and Pamela DiLavore
• Structured play interview
conducted with the child
• Designed to provide
explicit presses for
language and social
behaviors that are
challenging for children
with autism
Key Behaviors Coded in Module One Communication
• Frequency of vocalization
directed to others
• Stereotyped / Idiosyncratic
words or phrases
• Use of other’s body to
communicate
• Pointing
• Gestures
Key Behaviors Coded in Module One Social
• Unusual eye contact
• Facial expressions directed to
others
• Shared enjoyment in interaction
• Showing
• Spontaneous initiation of joint
attention
• Response to joint attention
• Quality of social overtures
Key Behaviors Coded in Module One Play
• Functional play with
objects
• Imagination /
Creativity
Key Behaviors Coded in Module One Stereotyped Behaviors
• Unusual sensory interest in play material
/ person
• Hand and finger and other complex
mannerisms
• Unusually repetitive interests or
stereotyped behaviors
Key Behaviors Coded in Module Two:
Communication
• Amount of social overtures
• Stereotyped / idiosyncratic words or
phrases
• Conversation
• Pointing to express interest
• Descriptive, conventional, instrumental
gestures
Key Behaviors Coded in Module
Two: Social Interaction
•
•
•
•
•
•
•
Unusual eye contact
Facial expressions directed to others
Spontaneous initiation of joint attention
Quality of social overtures
Quality of social response
Amount of reciprocal social communication
Overall quality of rapport
Key Behaviors Coded in Module
Two: Play
• Imagination / Creativity (“flexible,
creative use of objects in a
representational manner . . . Use or
description of figures or dolls as agents
of action”)
Key Behaviors Coded in Module Two:
Stereotyped Behaviors / Restricted
Interests
• Unusual sensory interest in play material
/ person
• Hand and finger and other complex
mannerisms
• Unusually repetitive interests or
stereotyped behaviors
Principles of Good Practice
• Components of diagnostic evaluation
– Diagnosis
– rationale for the diagnosis
– discussion of the implications of the child’s
strengths and challenges
– treatment and education recommendations
– follow-up to support the implementation of
the recommendations.
Principles of Good Practice
• Family-centered practice
– including the parents as full partners in the
assessment team
– communicating respect for their expertise and their
contribution to the assessment and treatment
planning process.
• Transdisciplinary practice
• Community collaboration