Autism mandates followed by large jump in spending by health plans on care for children with autism, said researchers.

A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health has found that the enactment of state laws mandating coverage of autism spectrum disorder (ASD) was followed by sizeable increases in insurer-covered ASD care and associated spending.

Over the past decade, 46 states have passed laws requiring ASD coverage of autism by private health insurers. The study found that children in states that required ASD coverage were more likely to receive treatment.

“The hope of patient advocates and policymakers was that these insurer mandates would increase care for children with autism, and they seem to have done that—in fact, the impact was even larger than we had expected,” said Colleen L. Barry, PhD, MPP, the Fred and Julie Soper Professor and Chair of the Department of Health Policy and Management at the Bloomberg School.

The results, Barry added, are important for states that have enacted such mandates to understand their impact, and also helpful for states considering whether to broaden mandates that are already in place. Barry is also affiliated faculty with the Johns Hopkins Wendy Klag Center for Autism and Developmental Disabilities at the Bloomberg School.

The study, published in the October issue of the journal Health Affairs, was a collaboration with researchers at the University of Pennsylvania. The research team examined data from three nationwide private health insurers (United Healthcare, Aetna, and Humana) from 2008 through 2012, the period in which most states enacted their mandates for ASD coverage.

The researchers compared children age 21 and under with autism who were and were not covered by state mandates. They examined whether autism mandates led to increases in the likelihood that a child’s care was paid for by private insurance and the amount spent on autism services. Their analysis found that being covered by a mandate in a given year increased by about 3.4 percent, on average, the probability that a child with ASD received ASD-specific health care services via private insurance. Associated total ASD-related health care spending was higher by about $924 per year for children covered by mandates, primarily through increased spending on outpatient services rather than hospitalizations.

“Spending increases on outpatient services of this size mean that kids are receiving many more services per year paid for by private insurance – these changes due to the mandates are big enough to make a real difference in these children’s lives,” Barry said.

The increases in care and associated spending were concentrated among children with ASDs who were younger than 12, and were highest among ASD children age five and under. This was not unexpected, Barry notes, since ASD therapies tend generally to be aimed at younger patients, whereas older patients more often receive care principally through schools.

The analysis also indicated that children with ASD covered by a state mandate tended to receive more ASD-specific care the longer a mandate law has been in place.

ASD coverage by private insurers is still an ongoing policy issue in many states, even those that mandate coverage. Some state mandates only require ASD coverage for children in narrow age ranges, even though treatment through childhood and into adulthood can be effective, and place caps on annual coverage amounts.

“We think the findings from this study can influence the debate in states that are thinking about expanding the scope of their laws by covering more children, especially those considering expanding their age eligibility to cover older children and those transitioning into adulthood,” Barry said.

Recent federal laws including the Affordable Care Act have introduced nationwide coverage mandates, including “parit