Early Generalized Overgrowth in Boys With Autism

• Type of Material: Article
• Authors: Katarzyna Chawarska, Yale University; Daniel Campbell, Yale University; Lisha Chen, Yale University; Frederick Shic, Yale University; Ami Klin, Emory University; Joseph Chang, Yale University
• Language: English
• Date: 2011-10-01
• Publisher: American Medical Association (AMA)
• Publication Version: Final Published Version
• Copyright Statement: ©2011 American Medical Association. All rights reserved.
• Final Published Version (URL): http://dx.doi.org/10.1001/archgenpsychiatry.2011.106
• Title of Journal or Parent Work: Archives of General Psychiatry
• ISSN: 0003-990X
• Volume: 68
• Issue: 10
• Start Page: 1021
• End Page: 1031
• Grant/Funding Information: This study was supported by the National Alliance for Autism Research Foundation (Dr Chawarska); the Autism Speaks Foundation (Dr Chawarska); grant U54 MH66494, Project 3 from the Studies to Advance Autism Research and Treatment, National Institute of Mental Health (Dr Chawarska); and grant P50 MH081756-01, Project 2 from the Autism Center of Excellence, National Institute of Child Health and Human Development (Dr Chawarska).
• Keywords: BRAIN SIZE; SPECTRUM DISORDERS; 1ST YEAR; GROWTH-FACTOR; SERUM-LEVELS; Science & Technology; 2ND YEAR; Psychiatry; PERVASIVE DEVELOPMENTAL DISORDERS; NEUROTROPHIC FACTOR; Life Sciences & Biomedicine; HEAD CIRCUMFERENCE; LIFE
• Research Categories: Psychology, Developmental; Health Sciences, Mental Health

Abstract

Context: Multiple studies have reported an over-growth in head circumference (HC) in the first year of life in autism. However, it is unclear whether this phenomenon is independent of overall body growth and whether it is associated with specific social or cognitive features. Objectives: To examine the trajectory of early HC growth in autism compared with control groups; to assess whether HC growth in autism is independent of height and weight growth during infancy; and to examine HC growth from birth to 24 months in relationship to social, verbal, cognitive, and adaptive functioning levels. Design: Retrospective study. Setting: A specialized university-based clinic. Participants: Boys diagnosed as having autistic disorder (n=64), pervasive developmental disorder-not otherwise specified (n=34), global developmental delay (n=13), and other developmental problems (n=18) and typically developing boys (n=55). Context: Multiple studies have reported an overgrowth in head circumference (HC) in the first year of life in autism. However, it is unclear whether this phenomenon is independent of overall body growth and whether it is associated with specific social or cognitive features. Objectives: To examine the trajectory of early HC growth in autism compared with control groups; to assess whether HC growth in autism is independent of height and weight growth during infancy; and to examine HC growth from birth to 24 months in relationship to social, verbal, cognitive, and adaptive functioning levels. Design: Retrospective study. Setting: A specialized university-based clinic. Participants: Boys diagnosed as having autistic disorder (n=64), pervasive developmental disorder-not otherwise specified (n=34), global developmental delay (n=13), and other developmental problems (n=18) and typically developing boys (n=55). Main Outcome Measures: Age-related changes in HC, height, and weight between birth and age 24 months; measures of social, verbal, and cognitive functioning at age 2 years. Results: Compared with typically developing controls, boys with autism were significantly longer by age 4.8 months, had a larger HC by age 9.5 months, and weighed more by age 11.4 months (P=.05 for all). None of the other clinical groups showed a similar overgrowth pattern. Boys with autism who were in the top 10% of overall physical size in infancy exhibited greater severity of social deficits (P=.009) and lower adaptive functioning (P=.03). Conclusions: Boys with autism experienced accelerated HC growth in the first year of life. However, this phenomenon reflected a generalized process affecting other morphologic features, including height and weight. The study highlights the importance of studying factors that influence not only neuronal development but also skeletal growth in autism.