How Likely Is It That Autism Recurs in One Family?

Autism runs in families, a new study finds Children are seven times more likely to receive an autism diagnosis if an older sibling is autistic The more siblings with autism, the greater a younger child’s risk FRIDAY, Aug. 9, 2024 (HealthDay News) -- There’s a good chance that if one child in a family has autism, another will also develop the disorder, a new study suggests. Children are seven times more likely to be diagnosed with autism if an older sibling has the disorder, researchers reported recently in the journal .

“Pediatricians and family members have to keep a diligent eye on infants born into families with an already diagnosed autistic child,” said researcher , vice president and executive director at the Kennedy Krieger Institute’s Center for Autism Services, Science and Innovation. “Early referral for diagnostic evaluation is crucial to ensure support, resources and intervention.” For the study, researchers analyzed data from more than 1,600 infants with an older sibling with autism.

The infants were evaluated repeatedly between the age of 6 months and 3 years old. Results showed that 1 in 5 children (20%) whose older sibling has autism are likely to be diagnosed with the disorder as well. The risk increases with the number of autistic siblings.

More than 1 in 3 (36%) children will develop autism if they have more than one older sibling with the disorder, results showed. The study also found that the sex of a child significantly influences risk of aut.