Paternal age in autism spectrum disorders and ADHD.

Increased paternal age has been associated with an increased risk for autism spectrum disorders. The present study compared the paternal age distribution in autism spectrum disorders children with that of the general population and among children with attention deficit hyperactivity disorder. Study participants were drawn from the records of children diagnosed with one of these conditions in the years 1998-2006 at the Weinberg Child Development Center, Israel. Data regarding paternal age distribution in the general Israeli population were drawn from the yearly official publications of the Central Bureau of Statistics, Israel. Paternal age at the child's birth was found for autism spectrum disorders children (n = 268) and attention deficit hyperactivity disorders children (n = 320). Paternal age distribution of the attention deficit hyperactivity disorder children was similar to that of the general population in Israel, whereas autism spectrum disorders children were born to older fathers, compared with either the general population (P < 0.001) or children with attention deficit hyperactivity disorder (P = 0.04). These results support the claim that increased paternal age is associated with a birth of a child with autism spectrum disorders, but indicate that this finding cannot be generalized to attention deficit hyperactivity disorder.