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Early behavioral profiles elucidating vulnerability and resiliency to later ASD outcomes

Published online by Cambridge University Press:  15 September 2020

Rebecca J. Landa*
Affiliation:
Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD, USA Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
Rachel Reetzke
Affiliation:
Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD, USA Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
Madiha Tahseen
Affiliation:
Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD, USA
Christine Reiner Hess
Affiliation:
Center for Autism and Related Disorders, Kennedy Krieger Institute, Baltimore, MD, USA
*
Author for Correspondence: Rebecca J. Landa, Ph.D., CCC-SLP, Center for Autism and Related Disorders, Kennedy Krieger Institute, 3901 Greenspring Ave, Baltimore, MD 21211 USA. E-mail: Landa@kennedykrieger.org

Abstract

Infant siblings of children with autism spectrum disorder (ASD) exhibit greater heterogeneity in behavioral presentation and outcomes relative to infants at low familial risk (LR), yet there is limited understanding of the diverse developmental profiles that characterize these infants. We applied a hierarchical agglomerative cluster analysis approach to parse developmental heterogeneity in 420 toddlers with heightened (HR) and low (LR) familial risk for ASD using measures of four dimensions of development: language, social, play, and restricted and repetitive behaviors (RRB). Results revealed a two-cluster solution. Comparisons of clusters revealed significantly lower language, social, and play performance, and higher levels of restricted and repetitive behaviors in Cluster 1 relative to Cluster 2. In Cluster 1, 25% of children were later diagnosed with ASD compared to 8% in Cluster 2. Comparisons within Cluster 1 between subgroups of toddlers having ASD+ versus ASD− 36-month outcomes revealed significantly lower functioning in the ASD+ subgroup across cognitive, motor, social, language, symbolic, and speech dimensions. Findings suggest profiles of early development associated with resiliency and vulnerability to later ASD diagnosis, with multidimensional developmental lags signaling vulnerability to ASD diagnosis.

Type
Special Section Articles
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

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