Head circumference and height in autism: a study by the Collaborative Program of Excellence in Autism.
Data from 10 sites of the NICHD/NIDCD Collaborative Programs of Excellence in Autism were combined to study the distribution of head circumference and relationship to demographic and clinical variables. Three hundred thirty-eight probands with autism-spectrum disorder (ASD) including 208 probands with autism were studied along with 147 parents, 149 siblings, and typically developing controls. ASDs were diagnosed, and head circumference and clinical variables measured in a standardized manner across all sites. All subjects with autism met ADI-R, ADOS-G, DSM-IV, and ICD-10 criteria. The results show the distribution of standardized head circumference in autism is normal in shape, and the mean, variance, and rate of macrocephaly but not microcephaly are increased. Head circumference tends to be large relative to height in autism. No site, gender, age, SES, verbal, or non-verbal IQ effects were present in the autism sample. In addition to autism itself, standardized height and average parental head circumference were the most important factors predicting head circumference in individuals with autism. Mean standardized head circumference and rates of macrocephaly were similar in probands with autism and their parents. Increased head circumference was associated with a higher (more severe) ADI-R social algorithm score. Macrocephaly is associated with delayed onset of language. Although mean head circumference and rates of macrocephaly are increased in autism, a high degree of variability is present, underscoring the complex clinical heterogeneity of the disorder. The wide distribution of head circumference in autism has major implications for genetic, neuroimaging, and other neurobiological research.
Lainhart
Janet E
JE
Department of Psychiatry, The Brain Institute at the University of Utah, Salt Lake City, Utah 84108, USA. janet.lainhart@hsc.utah.edu
Bigler
Erin D
ED
Bocian
Maureen
M
Coon
Hilary
H
Dinh
Elena
E
Dawson
Geraldine
G
Deutsch
Curtis K
CK
Dunn
Michelle
M
Estes
Annette
A
Tager-Flusberg
Helen
H
Folstein
Susan
S
Hepburn
Susan
S
Hyman
Susan
S
McMahon
William
W
Minshew
Nancy
N
Munson
Jeff
J
Osann
Kathy
K
Ozonoff
Sally
S
Rodier
Patricia
P
Rogers
Sally
S
Sigman
Marian
M
Spence
M Anne
MA
Stodgell
Christopher J
CJ
Volkmar
Fred
F
D000293:Adolescent; D000328:Adult; D001321:Autistic Disorder / Q000175:diagnosis / Q000473:pathology* / Q000523:psychology; D001827:Body Height; D016022:Case-Control Studies; D002508:Cephalometry; D002648:Child; D002675:Child, Preschool; D003299:Cooperative Behavior; D019465:Craniofacial Abnormalities / Q000473:pathology; D005260:Female; D006257:Head / Q000473:pathology*; D006801:Humans; D007360:Intelligence; D008297:Male; D008875:Middle Aged; D009316:National Institutes of Health (U.S.); D010290:Parents; D012016:Reference Values; D035781:Siblings; D012959:Socioeconomic Factors; D014481:United States