Patterns of Mental Health Service Use During the Transition to Adulthood Among Autistic Adolescents and Young Adults.

Background: The time of transition into adulthood, especially when leaving school, is a time when many autistic adolescents and young adults (AYA) may stop receiving mental health services that they have relied on, leading to worse mental health outcomes. The purpose of this study was to describe patterns of mental health service use during transition to adulthood among autistic AYAs. Methods: We performed a cross-sectional study using electronic health records from years 2015 to 2019 from one large university health care system. We included autistic individuals ages 11-27 with at least one clinical encounter annually in the cohort. Outcomes included psychotropic medications and psychotherapy received, psychotropic polypharmacy, psychiatric emergency department (ED) visits, and adverse drug events. Results: Almost half of the 529 patients in the cohort received polypharmacy. The most common treatment was medication only (56.9%), followed by no treatment (22.7%), medication plus psychotherapy (18.7%), and psychotherapy only (data masked). The 17-21 age group had the highest odds of a psychiatric ED visit, whereas the 22-27 age group had the highest odds of receiving psychotropic medications and polypharmacy. Black AYA were more likely to receive psychotherapy and less likely to receive psychotropic polypharmacy than non-Hispanic Whites. Conclusion: Autistic individuals may benefit from more support from the health care system for their transition into adulthood to maintain use of beneficial mental health services as they leave school and to reduce the frequency of adverse outcomes. Access to providers experienced treating the complex needs of autistic individuals is important to reduce disparities.