Macrocephaly in Children With Autism Spectrum Disorders

Department of Educational Psychology, Baylor University, Waco, Texas 76798, USA.
Pediatric Neurology (Impact Factor: 1.5). 02/2011; 44(2):97-100. DOI: 10.1016/j.pediatrneurol.2010.09.011
Source: PubMed

ABSTRACT Research indicates the presence of macrocephaly or abnormally large head circumferences in children with autism and spectrum-related disorders, compared with their typically developing peers. Previous research, however, centered on non-nationally representative, clinic-based samples of children and adults with autism spectrum disorders. Moreover, these samples were typically small. The present study represents results of a nationally representative, community-based sample of children with and without autism spectrum disorders, derived from the Early Childhood Longitudinal Study Birth Cohort. Results reveal statistically nonsignificant differences in the head circumferences of children with autism spectrum disorders across three time points, compared with children without autism spectrum disorders. These results may be considered highly generalizable, because they are derived from a nationally representative, community-based sample of children with and without autism spectrum disorders from the Early Childhood Longitudinal Study Birth Cohort.

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    ABSTRACT: Numerous clinical studies over the past decades have concluded that there is an association between autism spectrum disorders (ASD) and large head size. Lately, some studies have reported conflicting results. The present study was conducted with a view to assess the presence of macrocephaly in a community-representative group of pre-school children with ASD. The prevalence of ASD in this general population was 0.8%. Thirty-three children (5 girls, 28 boys) recruited after general population screening for ASD, and diagnosed with ASD (two-thirds not globally delayed) were assessed as regards growth parameters; height, weight, and head circumference (HC), at birth and at comprehensive medical-psychiatric diagnostic examinations at a mean age of 3 years. Macrocephaly in the present study was defined as HC above the 97th percentile, and ≥2 SD above recorded length/height. Only one of the 33 children (3%) had macrocephaly which is similar to the general population prevalence. Another 9% had a big but proportional head. None of the children were microcephalic. In this community-based study we found no evidence to support a strong link between a large head size and ASD. Conclusions must be guarded because of the relatively small number of ASD cases included.
    Research in developmental disabilities 05/2014; 35(5). DOI:10.1016/j.ridd.2014.02.006 · 4.41 Impact Factor
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