TY - JOUR AU - S. Sandelich AU - C. Buresh AU - S. Axson AU - B. Linn AU - M. Mareboina A1 - AB - PURPOSE: The co-occurrence of substance use disorders and mental health disorders in adolescents, known as dual diagnosis, complicates treatment adherence, heightens relapse risk, and increases engagement in risky behaviors. This study contrasts these groups' healthcare utilization, interventions, and clinical profiles. METHODS: In a retrospective, longitudinal cohort study using the TriNetX Research Database, we analyzed data from 82 U.S. healthcare organizations. The study encompassed 1,757,913 adolescents aged 10 to 21 diagnosed with substance use disorders, mental health disorders, and a combination of both from 2004 to 2023. Propensity score matching was applied to adjust for demographic and clinical variables, assessing healthcare utilization, treatment initiation, and social challenges. RESULTS: Among 1,757,913 adolescents, 14.0 % (n = 246,776) had a dual diagnosis. Compared with isolated MHD, adolescents with DDx had significantly higher odds of emergency department use (OR 2.64, 95 % CI 2.27-2.70) and inpatient hospitalization (OR 2.73, 95 % CI 2.69-2.77). Relative to isolated SUD, DDx also showed elevated ED use (OR 1.56, 95 % CI 1.53-1.58) and inpatient care (OR 2.55, 95 % CI 2.50-2.61). Pharmacologic treatment initiation was more common in DDx, including antidepressants (53.1 % vs. 44.8 % MHD; OR 1.40, 95 % CI 1.38-1.42) and antipsychotics (35.5 % vs. 18.9 % MHD; OR 2.36, 95 % CI 2.33-2.39). DDx also demonstrated higher rates of social and environmental problems (19.3 % vs. 8.6 % MHD and 3.9 % SUD). DISCUSSION: Adolescents with dual diagnoses constitute a distinct demographic with intricate clinical profiles and heightened healthcare needs, emphasizing the need for integrated care approaches that address clinical symptoms and social determinants. Early identification and comprehensive interventions are crucial to improving outcomes. AD - Department of Emergency Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA, United States of America; Penn State College of Medicine, Hershey, PA, United States of America. Electronic address: ssandelich@pennstatehealth.psu.edu.; Department of Emergency Medicine, University of Washington, Seattle, WA, United States of America.; Ross and Carol Nese College of Nursing, University Park, PA, United States of America.; Department of Family and Community Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA, United States of America.; Penn State College of Medicine, Hershey, PA, United States of America. AN - 41352628 BT - J Affect Disord C5 - Opioids & Substance Use; Healthcare Disparities DA - Mar 1 DO - 10.1016/j.jad.2025.120808 DP - NLM ET - 20251204 JF - J Affect Disord LA - eng N2 - PURPOSE: The co-occurrence of substance use disorders and mental health disorders in adolescents, known as dual diagnosis, complicates treatment adherence, heightens relapse risk, and increases engagement in risky behaviors. This study contrasts these groups' healthcare utilization, interventions, and clinical profiles. METHODS: In a retrospective, longitudinal cohort study using the TriNetX Research Database, we analyzed data from 82 U.S. healthcare organizations. The study encompassed 1,757,913 adolescents aged 10 to 21 diagnosed with substance use disorders, mental health disorders, and a combination of both from 2004 to 2023. Propensity score matching was applied to adjust for demographic and clinical variables, assessing healthcare utilization, treatment initiation, and social challenges. RESULTS: Among 1,757,913 adolescents, 14.0 % (n = 246,776) had a dual diagnosis. Compared with isolated MHD, adolescents with DDx had significantly higher odds of emergency department use (OR 2.64, 95 % CI 2.27-2.70) and inpatient hospitalization (OR 2.73, 95 % CI 2.69-2.77). Relative to isolated SUD, DDx also showed elevated ED use (OR 1.56, 95 % CI 1.53-1.58) and inpatient care (OR 2.55, 95 % CI 2.50-2.61). Pharmacologic treatment initiation was more common in DDx, including antidepressants (53.1 % vs. 44.8 % MHD; OR 1.40, 95 % CI 1.38-1.42) and antipsychotics (35.5 % vs. 18.9 % MHD; OR 2.36, 95 % CI 2.33-2.39). DDx also demonstrated higher rates of social and environmental problems (19.3 % vs. 8.6 % MHD and 3.9 % SUD). DISCUSSION: Adolescents with dual diagnoses constitute a distinct demographic with intricate clinical profiles and heightened healthcare needs, emphasizing the need for integrated care approaches that address clinical symptoms and social determinants. Early identification and comprehensive interventions are crucial to improving outcomes. PY - 2026 SN - 0165-0327 SP - 120808 ST - Healthcare utilization patterns among adolescents with dual diagnoses of mental health and substance use disorders T1 - Healthcare utilization patterns among adolescents with dual diagnoses of mental health and substance use disorders T2 - J Affect Disord TI - Healthcare utilization patterns among adolescents with dual diagnoses of mental health and substance use disorders U1 - Opioids & Substance Use; Healthcare Disparities U3 - 10.1016/j.jad.2025.120808 VL - 396 VO - 0165-0327 Y1 - 2026 ER -