Early social-communicative and cognitive development of younger siblings of children with autism spectrum disorders. s
Stone WL, McMahon CR, Yoder PJ, Walden TA.
Archives of Pediatric and Adolescent Medicine. 2007; 161:384-390.
Bottom Line Many of the young siblings of children with ASD who participated in this study had symptoms of autism in the second year of life. Early identification and intervention could enhance their development. It should be kept in mind that not a lot of research has been done using the CARS with very young children, so the results should be interpreted with some caution. |
Question: Does the early social communication and cognitive development of the younger siblings of children with autism spectrum disorders (ASDs) differ from that of the younger siblings of typically developing children?
Background: The siblings of children with a diagnosis of ASD are at higher risk of developing the condition. There has been some suggestion that even if they don’t develop ASD, they may have some symptoms. Those with symptoms that don’t meet criteria for a diagnosis of ASD may have what is called the broader autism phenotype (BAP) which is much less disabling, but still presents everyday problems, like language difficulties, that would respond to intervention, especially if caught early.
Design: Two-group comparison study.
Setting: a major US university.
Participants: 106 children, aged 12 to 23 months: 42 younger siblings of children with ASD (Sibs-ASD) and 64 younger siblings of children with typical development (Sibs-TD). were tested only once at entry to the study.
Main Outcome Measures: Multiple tests and scales, including the Mullen Scales of Early Learning (MSEL), the Childhood Autism Rating Scale (CARS), and the MacArthur Communicative Development Inventories (MCDI).
Main Results: The siblings of children with ASD scored lower than the other sibling group on measures of general learning ability and their ability to understand and interpret visual information. 23 of the 64 ASD-sibs had scores on the CARS that were within the at-risk or clinical range and 25% of the Sibs-ASD had low scores on the other tests, indicating signs of autism symptoms, specifically for initiation of joint attention. There was no difference in expressive language skills between the two groups.
Conclusions: In this study, a large number of children with an older sibling with autism showed symptoms of autism, although not at a level that would rate a diagnosis of ASD. The symptoms could signal that these infants are at higher risk of ASD or related developmental problems (such as language disorders). Early identification and intervention with these children could help reduce some of the difficulties they would encounter as they matured.