Predictors of substance use disorder treatment initiation and engagement among adolescents enrolled in Medicaid.

Adolescents with substance use disorders (SUD) should receive timely access to treatment to improve lifelong outcomes. The Healthcare Effectiveness Data and Information Set (HEDIS) initiation and engagement in treatment (IET) performance measure was intended to promote quality improvement for patients with SUD. Yet, few studies have assessed predictors of measure performance among adolescents or other engagement in mental health services, which is critical to understanding disparities in treatment quality or opportunities for targeted improvement strategies. The present study reports the rates and predictors of IET among adolescents with SUD, as well as receipt of any mental health services. The sample included adolescents enrolled in Medicaid in 14 states who had a qualifying diagnosis for SUD (2009-2013) and met HEDIS IET performance measure eligibility criteria. Three outcomes were assessed, including initiation of SUD treatment within 14 days of qualifying diagnosis, engagement in SUD treatment (2 or more encounters) within 30 days of initiation, and receipt of any mental health services (1 or more encounters) within 30 days of initiation. Logistic regression was used to identify demographic and clinical characteristics associated with outcomes. Among 20,602 adolescents who met eligibility criteria, 49.5% initiated SUD treatment, 48.5% engaged in SUD treatment, and 70% received any mental health service. Adolescents with higher levels of clinical need (e.g., medical complexity, mental health comorbidity, and multiple SUD diagnoses) had significantly higher odds of initiating, but lower odds of engaging in treatment or receiving any mental health service. To increase the delivery of SUD treatment, efforts should target adolescents with co-occurring mental health needs, many of whom are receiving mental health services after SUD diagnosis. Integrating addiction and mental health services could address these missed opportunities.