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Diagnosis of autism spectrum disorders in the first 3 years of life

Nature Clinical Practice Neurology volume 4, pages 138–147 (2008)Cite this article

Abstract

Autism spectrum disorders (ASDs) are a class of neurodevelopmental disorders defined by qualitative impairments in social functioning and communication, often accompanied by repetitive and stereotyped patterns of behavior and interests. The term 'ASD' encompasses autism, pervasive developmental disorder not otherwise specified, and Asperger's syndrome. ASDs show etiologic heterogeneity, and there is no definitive medical test or cure for these conditions. Around 1 in 150 children have an ASD, with males being affected three to four times more frequently than females. The age at diagnosis of ASD ranges from 3 to 6 years, but there is increasing evidence that diagnosis in the second year of life is possible in some children. Early diagnosis will lead to earlier behavior-based intervention, which is associated with improvements in core areas, such as social functioning and communication. Early detection of—and intervention to treat—ASD is crucial because it is likely to lead to an improved outcome.

Key Points

  • Early signs of autism spectrum disorders (ASDs) include infrequent social orienting, infrequent initiation of social engagement, poorly sustained and coordinated engagement with others, a limited variety of gestures and other forms of communication, and repetitive motor behaviors

  • Development of siblings of children with ASDs and other groups at high risk of ASDs should be followed closely from 6 months of age onwards

  • Diagnosis of ASDs becomes possible at 14 months of age, but the diagnosis might be unstable in up to a third of children diagnosed before 30 months of age

  • Young children with ASDs show improved social, communication, language, play and cognitive functioning when they are enrolled in a developmentally appropriate intensive intervention

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Acknowledgements

This work was supported by grants MH59630 and MH066417 from the NIH, Bethesda, MD, USA, which were awarded to the author. Désirée Lie, University of California, Irvine, CA, is the author of and is solely responsible for the content of the learning objectives, questions and answers of the Medscape-accredited continuing medical education activity associated with this article.

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  1. Kennedy Krieger Institute, 3901 Greenspring Avenue, Baltimore, MD 21211, USA landa@kennedykrieger.org

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  1. RJ Landa is Associate Professor of Psychiatry at John Hopkins University, and Director of the Kennedy Krieger Institute's Center for Autism and Related Disorders, Baltimore, MD, USA.,

    Rebecca J Landa

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Landa, R. Diagnosis of autism spectrum disorders in the first 3 years of life. Nat Rev Neurol 4, 138–147 (2008). https://doi.org/10.1038/ncpneuro0731

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