Brief Report: Healthcare Utilization and Expenditure Trends Among Autistic Transition Age Youth

The transition to adult healthcare is a vulnerable time for individuals with autism spectrum disorder (ASD). Prior research using Medicaid data (2001–2005) found this group had declining utilization rates into adulthood for some types of care (e.g., psychiatric outpatient). Substantial changes to Medicaid and the ASD population have occurred since this time. We reassessed healthcare resource utilization (HCRU) across the transition to adulthood Medicaid claims data from 2015 to 2019. We selected enrollees with at least one fee for service claim, aged 16–19 years in 2015, who were also enrolled in 2019 using diagnostic groupings: ASD/no ID (n = 23,460), ID/no ASD (n = 21,256) and ASD + ID (n = 10,115). HCRU indicators included utilization rates and per capita expenditures for outpatient, inpatient, long-term, and medication care, with each type further divided into psychiatric and non-psychiatric (i.e., medical). The ID groups had overall higher HCRU than the ASD only group. ASD + ID adults had especially high HCRU for psychiatric outpatient care. HCRU increased into adulthood for psychiatric outpatient and long-term care, driven by higher expenditures among those with >$0 expenditures. HCRU declined into adulthood for inpatient care and medication use. In contrast to 2001–2005, having an ID diagnosis resulted in greater HRCU across transition to adulthood, potentially reflecting changes in the Medicaid ASD population over time. Consistent with 2001–2005, utilization rates generally declined for all three groups across the transition to adulthood. Greater expenditure among those using psychiatric outpatient and long-term care in adulthood resulted in greater overall resource utilization than adolescence.