The gap is mainly due to mothers not having a job or working fewer hours, researchers found.

"The needs of children with autism really straddle a number of service systems and there is a tremendous amount of finger pointing in terms of who's going to pay," said David Mandell, associate director of the Center for Autism Research at The Children's Hospital of Philadelphia.

"Mothers are leaving the workforce to cobble this care together for their kids," he added.

Autism spectrum disorders, which range from mild Asperger's syndrome to severe mental retardation and social disability, affect about one in 110 children in the U.S., according to the Centers for Disease Control and Prevention.

As more and more kids are diagnosed with the disorders, the nation is grappling with how to pay for the extra care these children need, which may cost as much as $3.2 million over a lifetime.

Mandell said that until now, the impact on individual families in terms of employment and earnings had not been clear.

For the new work, Mandell's group used data from national household surveys done yearly between 2002 and 2008, including 261 children with autism and more than 64,000 without health problems.

After accounting for factors such as parents' age, race, education and health, fathers of kids with autism were just as likely to be employed as fathers of typically developing children. The same was true for how much fathers worked and earned.

For mothers, however, there was a marked difference. Compared with mothers of kids without disabilities, those who had autistic children were six percent less likely to be employed, worked seven hours less per week and had less than half the annual income.

All told, households with autistic children earned $17,763 less a year.

The researchers couldn't say for sure that the gap is caused by having a child with autism. But Mandell said today's system means families have to shuttle their kids between several different providers.

"I think it's a case of the mother becoming the case manager and the advocate for the child," he told Reuters Health. "If these kids were appropriately cared for it wouldn't be such a burden for the family."

Guillermo Montes, a researcher at St. John Fisher College in Rochester, New York, said the new study shows families with children with autism make different financial decisions than others.

"By putting their kids first, these decisions result in lower and more unstable family income," Montes, who was not involved in the new work, told Reuters Health by email.

"State legislatures, employers and the federal government have to engage these families in a conversation about how to best assist them," he added. "Any assistance must preserve work flexibility and the wide variety of work and care arrangements which are key to achieve a work-family balance that works for kids with autism, their siblings and their parents."

SOURCE: bit.ly/cxXOG Pediatrics, March 19, 2012.

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