title: Early generalized overgrowth in boys with autism.
abstract: BACKGROUND
  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.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  A specialized university-based clinic.
  
  
  METHODS
  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).
  
  
  METHODS
  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.
authors.affiliation: Child Study Center, Yale University School of Medicine, New Haven, CT, USA. Katarzyna.chawarska@yale.edu
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Chawarska
authors.forename: Daniel
authors.initials: D
authors.lastname: Campbell
authors.forename: Lisha
authors.initials: L
authors.lastname: Chen
authors.forename: Frederick
authors.initials: F
authors.lastname: Shic
authors.forename: Ami
authors.initials: A
authors.lastname: Klin
authors.forename: Joseph
authors.initials: J
authors.lastname: Chang
mesh_terms: D001321:Autistic Disorder / Q000473:pathology* / Q000523:psychology; D001499:Bayes Theorem; D001827:Body Height; D001835:Body Weight; D016022:Case-Control Studies; D006257:Head / Q000254:growth & development*; D006801:Humans; D007223:Infant; D008297:Male; D058627:Megalencephaly / Q000473:pathology / Q000523:psychology; D012189:Retrospective Studies