Yet Another Purported Risk Factor: Paternal Obesity

The number of purported risk factors for autism has become bewildering.  MedPage Today reports:

Paternal obesity was strongly associated with increased risk for several autism spectrum disorders in children, according to a population-based study.

Children of obese fathers had an increased risk for developing autistic disorder and Asperger disorder, and the risk grew with increasing body mass index (BMI), wrote Pål Surén, MD, MPH, of the Norwegian Institute of Public Health in Oslo, and colleagues, in the May issue of Pediatrics.
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"We had thought that maternal obesity may somehow be related to autism, but this is the first time anyone has looked at paternal weight, and the findings suggest we may have gotten it wrong," commented Andrew Adesman, MD, chief of developmental and behavioral pediatrics at Steven & Alexandra Cohen Children's Medical Center of New York in Lake Success, N.Y.

Adesman, who was not involved in the current research, pointed out that it's not clear from either of the studies if obesity plays a causal role in autism. Even if future studies did demonstrate causality, the impact of parental obesity on autism spectrum disorders is likely to be small, he added.

"Most of the children with autism in this study were not born to obese fathers and most of the children born to obese fathers did not develop autism," he told MedPage Today. "The risk (for autistic disorder) increased from 15 per 10,000 cases (children with normal-weight dads) to 25 in 10,000 cases (children with obese dads), which is still very, very low."