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Early identification of Autism Spectrum Disorders

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Early identification of Autism Spectrum Disorders Powered By Docstoc
					  Early identification of
Autism Spectrum Disorders

          Catherine Lord
University of Michigan Autism and
 Communication Disorders Center
            (UMACC)
                   Collaborators

Pamela C. DiLavore         Deborah Anderson
Susan Risi                 Rosalind Oti
Cory Shulman               Michael Rutter
Audrey Thurm               Andrew Pickles
Families and children in    Rebecca Niehus
the Early Diagnosis
project                     Rhiannon Luyster
Can autism and ASD be reliably diagnosed at age 2?
Is there a reason to distinguish narrowly defined autism
  from more broadly defined ASD in young children?
What are the trajectories associated with early development in ASD?
Autism as a developmental disorder:
What is manifested as autism changes with
development
Development is affected by having autism
• Both positive (abnormal) behaviors, and negative
  (the absence of normal) behaviors are required to
  make a diagnosis of ASD.
• This means that developmental level and
  contextual effects (in what kind of circumstances
  does the child or adult function?) can both have
  significant effects on diagnostic judgments.
Information from earlier studies
• Conflicting information from treatment
  versus epidemiological/longitudinal studies
• Empirical studies of preschool children
  •   Joint attention: response to/initiation
  •   Looking at faces; gaze
  •   Response to name
  •   Pretending
Canadian follow-up study (N = 30)
• Clearest discriminators at age two
  from parent report (ADI)
  • Attention to voice
  • Child spontaneously directing
    other’s attention (in any way)
  • Understands no words out of context
Clearest discriminators at age three
  •   Attention to voice
  •   Pointing to express interest
  •   Hand and finger mannerisms
  •   Use of other’s body as a tool
  •   Uses no meaningful words spontaneously
North Carolina/Chicago
 Early Diagnosis Study

               Multiple measures
               Parent report and direct
               observations
               Larger sample
               Greater diversity
           Participants with 9 Year-Old Data
                              Mean
                                         Mean Age     Mean     Mean
              Race   Gender Age in
                                         in Mos. at   VIQ      NVIQ
             (B/W)   (M/F)   Mos. at
                                          Last Test   Age 9    Age 9
              (%)     (%)   First Test
                                            (SD)      (SD)     (SD)
                              (SD)
N.                             28.7        122.0       52.4     67.2
Carolina     39/58   77/23     (4.8)       (8.3)      (39.3)   (23.6)
n=102
Chicago                        29.3         98.2       55.6     74.3
  s.         8/86    85/15                            (37.6)
n=68                           (5.6)       (10.9)              (18.1)
Can autism and ASD be reliably diagnosed at age 2?
Percent of age two diagnostic combinations and best-estimate
       judgments accurately predicting diagnosis at 9




            (Age 2 best-estimate autism prevalence based on N=214)
            [Age 9 best-estimate autism prevalence based on N=172]
                Best Estimate Diagnoses at
                2 and 9 (NC and Chicago)
                                    At 9 years

                           Autism   PDD-NOS      Nonspectrum
At 2 years




               Autism        76         13            1

              PDD-NOS        27         11            6

             Nonspectrum     2           9           34
 Using Best Estimate Diagnoses:
 Overall diagnoses of autism were very stable from 2-9
      Of children who had a diagnosis of autism at 2
           84% had autism diagnoses at 9
           15% had PDD-NOS dx at 9
            1% had nonspectrum dx


                                                         Autism at 9
                                                         PDD-NOS at 9
                                                         Nonspectrum at 9


Of children who had a diagnosis of autism at 9
   71% had autism diagnoses at 2
   27% had PDD-NOS dx at 2
    2% had nonspectrum dx at 2

                                                            Autism at 2
                                                            PDD-NOS at 2
                                                            Nonspectrum at 2
Is there a reason to distinguish narrowly defined autism
  from more broadly defined ASD in young children?
Two Year-old Measures Predicting ASD at 9,
    including Best Estimate Diagnosis
         (est. R2 = .63; TPV = 92%)

                  OR     se      z       p

  BEST             .05   0.04   -4.38   .001
  ESTIMATE
  DIAGNOSES
  ADI-R           2.28   0.56   3.38    .001
  Repetitive
  Behaviors
  PL-ADOS         1.68   0.36   2.45    .014
  Repetitive
  Behaviors
Two Year-old Measures Predicting ASD at 9,
    excluding Best Estimate Diagnosis
        (est. R2 = .52; TPV = 89%)
                   OR     se      z      p


ADI-R Repetitive   2.15   0.42   3.89   .001
Behaviors
PL-ADOS Social-    1.26   0.06   4.78   .001
Communication

PL-ADOS            1.47   0.23   2.49   .01
Repetitive
Behaviors
PDD-NOS as a category was much less stable
    Of children with PDD-NOS at 2
       61% autism at 9
       25% PDD-NOS at 9
       14% nonspectrum at 9

                                             Autism at 9
                                             PDD-NOS at 9
                                             Nonspectrum at 9




       Of children with PDD-NOS at 9:
          39% autism at 2
          33% PDD-NOS at 9
          27% nonspectrum at 9

                                                Autism at 2

                                                PDD-NOS at 2
                                                Nonspectrum at 2
More diagnostic changes were between 2 and 5.
   Between 2–5 21% more severe
                  13% less severe
                  65% same

                                                    Worse
                                                    Better
                                                    Same


   Between 5–9 11% more severe
                8% less severe
               81% same

                                                Worse
                                                Better
                                                Same
What are the trajectories associated with early development in ASD?
    Patterns of Change in VIQ
     From Age 2- to 9-Years

                               N=17
                                 N=18

                                 N=40
                               N=62
V
I
                                  N=36
Q

                                  N=78
                               N=93




               Age in Months
          Age in Months
    Patterns of Change in NVIQ
      From Age 2- to 9-Years

                               N=61



N
V                              N=68
I
Q
                               N=43




             Age in Months
Patterns of Change in ADOS Algorithm Totals
           From Age 2- to 9-Years

A                                   N=91   N=91
D
                                           N=19
O
S                                   N=46

                                           N=28

T                                   N=35   N=34
O
T


                    Age in Months
                  Age in Months
             Mullen Ratio IQ(7/29/05): VIQ – 55; NVIQ – 95
                 Younger sibling; minimal intervention
              20


              16

ADOS          12

Social            8


Scores            4


                  0
                      0   5     10      15      20      25




              8
              7

              6
              5
ADOS          4


Repetitive    3
              2

Scores        1
              0
                  0       5     10      15      20       25




                                 Age (mos)
            Mullen Ratio IQ(5/26/05): VIQ – 112; NVIQ – 98
         Younger sibling; intensive intervention (Verbal Behavior)
             20


             16

ADOS         12

Social           8

Scores           4


                 0
                     0       5   10   15   20     25   30   35




             8



ADOS         6


Repetitive   4
Scores
             2



             0
                 0       5       10   15   20     25   30   35



                                      Age (mos)
What would you tell professionals
 about giving early diagnoses?
At age 9
  • Don’t give too much
    information too soon
  • Don’t stress negative
    prognoses
  • Present all options
  • Provide written
    information
Summary

    Autism can be
    reliably diagnosed at
    2 years.

    Diagnoses of milder
    cases of ASD with
    less clinician
    certainty were less
    reliable over time.
Conclusions:
Most diagnostic change occurred before 5.


Most common outcome for children with
  PDD-NOS at 2 was autism, but there was
  great variation.

Little evidence of “complete” recovery (1).

A significant minority (1 in 6) is doing quite well.
Conclusions (cont):

Considerable improvement in verbal IQs from 2 to 5
  and 5 to 9.


Repetitive behavior was not crucial for diagnosis at
  age 2, but was an important predictor of
  diagnosis at 9.


Small differences in development made large
  differences in prognosis.
Estimates of Expressive Language Level
 at Age 9 -- Percent of 151 Participants
                           Chicago   North Carolina
  Complex sentences
  (ADOS Module 3)
                            40.9          39.6
Sentences but not fluent
  (ADOS Module 2)
                            35.3          28.9
Words but not sentences
  (ADOS Module 1;           10.5          16.8
      ADI-R = 1)
 No or few consistent
  words (ADI-R=2)           14.3          14.4
   University of Michigan Autism and
Communication Disorders Center (UMACC)

				
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