Early Identification of Autism: Early Characteristics, Onset of Symptoms, and Diagnostic Stability Authors: Sara Jane Webb, PhD and Emily J. H. Jones,

Early Identification of Autism: Early Characteristics, Onset of Symptoms, and

Diagnostic StabilityAuthors: Sara Jane Webb, PhD and Emily J. H. Jones, PhD

Infants & Young Children (2008)Vol. 22, No. 2, pp. 100-118

Article Review

Southside Tidewater CoPA - June 2009

Overview

Autism Spectrum Disorders include:• Autism• Pervasive Development Disorder – NOS• Asperger’s Disorder

DSM-IV: Impairments in social interaction & communication and the presence of a restricted repertoire of behavioral activities & interests


Overview

• Affects boys 3-4 times more often than girls• Typically diagnosed between ages of 3-4 years

old• Clear evidence of genetic involvement in

etiology of ASD = risk factors are present from birth

• 30% of parents identify concerns prior to 1 yr• 80% of parents identify concerns by 2 yrs of age


Early Characteristics of ASD in Infants

In general, there is relatively little research on ASD in infancy

• Theory – early characteristics may be affected by/reflective of “abnormal trajectories of brain development”

• Development is shaped by genes & environment• Child’s behavior influences the environment the child experiences

• How do we study this?– Retrospective Studies– Prospective Studies




Social Interest & Attention– Diminished social attention by age 1• Poor eye contact• Lack of response to speech• Reaction to engagement in play or interaction• Social smiling & expression of positive emotion• Expressive communication• Differences in affective responses to touch• Orientation to voices• Poor imitation skills



Social Interest & Attention• Difficulties with social interest & attention may

diminish an infant’s “opportunity to learn about and from the people around them…” (p. 102)

• RED FLAG – Failure to respond to own name by 12 months of age may be linked to later diagnosis of ASD or other developmental delays


Communication– Delays in sound production, vocal quality– Babbling and language at 12 months– Use of & response to gestures like pointing for shared

attentionJoint attention is critical to language development



Repetitive Behaviors & Other Domains– May be less commonly seen in infants/toddlers– Retrospective studies

• Object mouthing & exploratory activities with objects 0-6 mo• Unusual posturing/movement patterns, mobility, abnormal

muscle tone• Self-stimulatory behaviors• Different sensory responses – hyper and hypo (also common in

children with DD)

– Prospective studies• More limited toy play• Atypical motor mannerisms



Repetitive Behaviors & Other Domains– BOTH studies

• Passivity – “too good” OR Irritability• Atypical growth in head circumference

One of the first early biological risk factors– Birth – smaller to normal head circumference– 7-9 mo – accelerated head growth– Age 2 – enlarged head circum. & brain volume

“Growth rate may slow down after 12 mo, correlated to a slowing in acquisition or loss in skills in infants with autism.” Elder, et. al. (2008)



Important to Remember:

1 in 5 children with ASD seem to develop typically during the 1st year

20%-49% of children with ASD show significant regression or skill loss

Absence of early risk factors does not rule out later diagnosis of ASD


In general, there is a more information about ASD in toddlers because:

– By 24 months, 90% of parents recognize concerns with child’s development

– Most families express concerns to pediatrician by 18 months

Early Characteristics of ASD in Toddlers


Social Interaction– Attention/orienting to faces and voices– eye contact– Limited social engagement– Tendency for isolation



Language & Communication– Language concerns/delays – most commonly reported

by parents20%-25% of children with ASD remain nonverbal

Some children may not produce their 1st word until 18+ mo

– Babbling, complex vocalization, vocal imitation– Single words & phrases– Speech may be stereotyped or echolalic– Difficulties with receptive language & pragmatics– Prefer to listen to mechanical signals



Language & Communication– Coordination of gestures with vocalizations & eye gaze for

joint attention“2-4 yr olds with ASD may be equally likely to communicate

to request or protest” (p. 104)

– Difficulties in imitation; less likely to initiate– Less likely to show pleasure with JA experiences

Difficulties in JA and Imitation – proposed as core components in ASD (p. 104)

– Differences with Play• Less complex & less purposeful• Less symbolic



Repetitive Behavior & Other Domains– Repeated play with an object & repetitive body

movements (12 mo – 3 yrs)– Motor skills may be delayed– “Repetitive behaviors around age 2 may predict

later diagnosis” (p. 105)– Temperament & behavior concerns



Stability of Early Diagnosis

Diagnosis of ASD is made via:– Clinical Judgment– Comprehensive Behavioral Assessments (dev.

appropriate) See article for examples of assessments

Diagnoses before age 3 – “provisional diagnosis”– 90%-100% of children diagnosed with ASD between 2-3

yrs old received same dx at 1- and 2-year follow-ups– 88% of children in another study had same dx at 9 yrs old


Regression (or Skill Loss)

• Validated through analysis of home videos & prospective studies

• Regression or…skill “stagnation” (a failure to progress)?

• Mean reported age of regression – 19-21 mo• Seen in both early and late onset ASD• Rare for child to show truly typical

development before regression



• NOT linked to socioeconomic status, birth order, gender, ethnicity, family risk, or vaccines

• HOWEVER, families often report regression followed an event such as illness or stressor

• Skill Loss:– Spoken language– Socioemotional reciprocity

• Sensory or temperament difficulties


Important to Remember:

Early loss of language does not necessarily = poorer language skills when child is older

Most children appear to regain at least single words


Evidence is mixed about effect of regression on long-term development:– Poorer outcomes vs. No differences between

children who experienced regression and those who did not

RED FLAG – Regression of Developmental Skills



Implications for Practice

RECOMMENDATIONS Monitoring socioemotional development &

screening for ASD is critical

Monitoring & screening should be more intensive when working with high-risk groups

Advances in early detection require advances in early treatment


Monitoring socioemotional development & screening for ASD is critical

• “Relatively high prevalence of ASD” – monitoring as a critical public health measure

• Use research-based screeners see article for examples & info

• Follow-up after screening so important:– 14% of parents of children who show positive results on

screening waited 6 mo before seeking evaluation– 18% did not seek further evaluation at all




• Siblings of Children with ASD– Risk of ASD– Displaying delays/characteristics of “broader autism

phenotype” i.e. “cognitive or neural characteristics of family

members that resemble those found in individuals with ASD” (p. 107)

– More than 10% of siblings show communication & social skill delays

– Particular risk – difficulties in joint attention, language /gesture use




• Extreme PrematurityGeneral neurological vulnerability & seizures

• Certain Disorders appear to show higher rates of ASD– Tuberous Sclerosis– Fragile X Syndrome– Down Syndrome– Neurofibromatosis



Advances in early detection require advances in early treatment

• 2001 – “National Research Council recommended that preschool-aged children with ASD receive at least 25 hours of structured intervention weekly” (p. 110)

• Due to difficulties evaluating interventions with infants/toddlers – little is known about “general effectiveness, or the impact of individual differences on treatment outcome” (p. 110)

• Early intervention seems to be more effective than receiving intervention later in development



“Increasing awareness of these early signs among parents and practitioners in critical in ensuring that symptoms of

ASD are recognized and evaluated as soon as they appear, particularly for groups of children who may be

at increased risk…

Development and evaluation of treatment options for young children with ASD, and ensuring prompt access to currently available interventions for children with a new diagnosis, are critical goals as the field moves forward.”

(p. 111)

Summary


Documents

Early Identification of Autism: Early Characteristics, Onset of Symptoms, and Diagnostic Stability Authors: Sara Jane Webb, PhD and Emily J. H. Jones,