Updated

The cost of supporting people with autism spectrum disorders throughout their lives could be as high as $2.4 million per person, according to a new estimate.

The main drivers of costs among children with autism spectrum disorders (ASDs) were special education and lost productivity for parents, researchers found. Among adults, the main drivers of costs were residential care and their own lost productivity.

“I think they really are the most thorough and trustworthy estimates that we have,” Tristram Smith said.

Smith, who was not involved with the new analysis, is an autism specialist at the University of Rochester Medical Center in Rochester, New York.

The researchers write in JAMA Pediatrics that previous cost estimates typically looked at individual areas, such as healthcare. The new study takes several other factors into account, including productivity, societal costs and other indirect costs.

For the analysis, the authors searched the medical literature for studies about costs associated with ASDs.

They compiled the data and found that the lifetime cost of supporting a person with an ASD and intellectual disability - formerly referred to as mental retardation - added up to $2.4 million in the U.S. and about $2.2 million in the UK.

For those without an intellectual disability, the lifetime cost was about $1.4 million in both the U.S. and the UK.

“These costs are much higher than previously suggested,” the researchers write. “Much of the high cost associated with ASDs is due to the cost of special education in childhood and to costs associated with residential accommodation, medical care, and productivity losses in adulthood.”

“My hope is that this is the beginning of a conversation - not the end,” David Mandell said. “And the things that will drive the conversation are those specific cost drivers.”

Mandell is the study’s senior author and director of the Center for Mental Health Policy and Services Research at the University of Pennsylvania in Philadelphia.

“We can be more effective and more efficient about service delivery,” he told Reuters Health. “This is the case where being consistent with our values as a society and lowering costs work completely hand in hand.”

While it’s hard to make comparisons, Smith said it appears that the lifetime cost of supporting someone with an ASD is higher than the cost of supporting people with intellectual disabilities.

“I think we’ve had a sense that especially as the individual enters adulthood, things like residential care are going to be the main cost drivers,” he said. “I think in a general way we’ve suspected it all along. We’ve been slow to respond to that so I think there has been more focus on the transition between youth and adulthood.”

In an editorial accompanying the new study, Paul Shattuck and Anne Roux of the A.J. Drexel Autism Institute at Drexel University in Philadelphia write that the analysis is “remarkable” given the lack of information on costs and outcomes among people with ASDs.

“For the person with autism, diagnosis is a doorway into a social role as a potential lifelong service user,” they write. “For families, an autism diagnosis can also mean a lifetime of absorbing many of the financial and caregiving burdens associated with the disorder, especially in adulthood when the availability of societal supports diminishes.”

Smith said the study points to areas that need additional research, such as the average life expectancy of people with autism and whether they’re at an increased risk of other conditions.

“I think it is a big step forward because they incorporate everything we know - which isn’t a lot - but it’s a big step forward over previous estimates,” he said.