Relation between early motor delay and later communication delay in infants at risk for autism.

BACKGROUND Motor delays have been reported in retrospective studies of young infants who later develop Autism Spectrum Disorders (ASDs). OBJECTIVE In this study, we prospectively compared the gross motor development of a cohort at risk for ASDs; infant siblings of children with ASDs (AU sibs) to low risk typically developing (LR) infants. METHODS 24 AU sibs and 24 LR infants were observed at 3 and 6 months using a standardized motor measure, the Alberta Infant Motor Scale (AIMS). In addition, as part of a larger study, the AU sibs also received a follow-up assessment to determine motor and communication performance at 18 months using the Mullen Scales of Early Learning. RESULTS Significantly more AU sibs showed motor delays at 3 and 6 months than LR infants. The majority of the AU sibs showed both early motor delays and later communication delays. LIMITATIONS Small sample size and limited follow-up. CONCLUSIONS Early motor delays are more common in AU sibs than LR infants. Communication delays later emerged in 67-73% of the AU sibs who had presented with early motor delays. Overall, early motor delays may be predictive of future communication delays in children at risk for autism.