PROJECT SUMMARY Over 3 million adolescents are diagnosed annually with major depressive disorder (MDD). Adolescent MDD predicts lifelong risk of chronic medical conditions, psychosocial disability, and death by suicide. Current evidence-based practices for adolescent MDD, such as standard cognitive behavioral therapy, are time and resource intensive while still leaving some adolescent MDD symptoms, including sleep disturbance and fatigue, unresolved. Capitalizing on adolescents’ near ubiquitous use of technologies, including smartphones and wearable devices, this proposal aims to develop an innovative and scalable digital tool (i.e., Sidekick) that will deliver a just-in-time adaptive intervention for adolescent MDD treatment within outpatient primary care. This R61/R33 will test whether Sidekick engages core target mechanisms of sleep and physical activity for improving adolescent MDD and functioning. The R61 phase will expand an existing digital platform by developing and optimizing Sidekick’s intervention algorithms, conducting user testing, and testing whether Sidekick engages core treatment mechanisms (i.e., sleep duration and physical activity levels). Smartphones and smartwatches will collect passive data and ecological momentary assessments on sleep and physical activity. Sidekick will process these streams of data to identify periods where adolescents need just-in-time support to increase physical activity and improve sleep. Aim 1 will focus on developing and refining the algorithm that individually tailors intervention type and delivery timing. Aim 2 will consist of a micro-randomized trial with 30 adolescents receiving collaborative care for MDD to test whether youth demonstrate improved sleep (e.g., more sleep for insomnia, less sleep for hypersomnia) and increased physical activity when they receive (vs. do not receive) a Sidekick tailored intervention. Once we satisfy our “go” criteria of engaging sleep and physical activity targets, the R33 phase will conduct a moderately sized randomized control trial of 70 youth receiving collaborative care for MDD. Aim 3 will examine whether youth who receive Sidekick in combination with collaborative care vs. collaborative care alone demonstrate greater improvements in sleep, physical activity, MDD symptoms, and psychosocial functioning. To better prepare for a larger clinical trial, Aim 4 will assess whether Sidekick is feasible, acceptable, appropriate, usable, and engaging across all phases of the study. If successful, this project will have a significant, lasting impact on the field of adolescent mental health by creating a digitally delivered, just-in-time adaptive intervention that can overcome substantial barriers in accessing evidence-based interventions and assisting adolescents in their daily contexts where support is most needed. This research will set the stage for a series of R01s testing Sidekick in expanded settings and as an evidence-based therapy enhancement tool for other mental health problems that may benefit from in-the-moment physical activity and sleep support, like suicidality, inattention, and executive functioning difficulties.

PROJECT NARRATIVE Current evidence-based practices for adolescent depression, such as standard cognitive behavioral therapy, are time and resource intensive while still leaving some adolescent depression symptoms, including sleep disturbance and fatigue, unresolved. This study will develop and pilot test a just-in-time adaptive intervention (JITAI) for adolescents seeking depression treatment in primary care, a critical setting for reaching adolescents in need of mental health care. JITAIs are a novel technology-based approach that have the potential to increase the effectiveness of depression care by utilizing in-the-moment smartphone and wearable device data to identify vulnerable periods (e.g., periods of inactivity, poor sleep health) and provide timely, targeted interventions when they are most needed for a particular adolescent.