Significantly fewer young adults with autism are accessing medical and social services once they leave high school, a first-of-its-kind survey finds, and the disparity is particularly exaggerated among those from lower income and minority groups.

The results come from a telephone survey which asked parents or guardians of 410 individuals with autism who had recently finished high school about their use of medical or mental health services, speech therapy and case management since leaving high school or within the previous two years.

Nearly 40 percent said that they had not used any of the services in that time, according to findings reported in the February issue of the Archives of Pediatrics & Adolescent Medicine, a journal published by the American Medical Association.

Meanwhile, the number of young adults age 19 to 23 who did access services dropped in every category as compared to a similar analysis of data from six years earlier when the participants were still in high school. Most strikingly, the number of individuals receiving speech therapy declined by more than 65 percent.

All of the young adults qualified for special education services during their school years because they were identified as having an autism spectrum disorder. The participants are among 11,000 students that are being tracked by the Department of Education as part of a 10-year transition study.

While rates of assistance declined across the board once students left high school, the change was even more pronounced among students in certain demographic groups, the survey found. African Americans were three times more likely to do without services as opposed to white participants. Similarly, those with household incomes lower than $25,000 were six times more likely to forgo services compared to participants living in homes with earnings greater than $75,000.

“The number of youths in the United States diagnosed as having an ASD and entering young adulthood will continue to rise in the foreseeable future,” the authors write. “This study represents an important step in the process of building a foundation of evidence that can help improve services and foster independence and health among youths with ASDs.”

Specifically, the authors recommend that the Interagency Autism Coordinating Committee, which sets priorities for government autism research, focus particular attention on examining varying access to adult services depending on race and socioeconomic status.