PROJECT SUMMARY Only 17% of adolescents with type 1 diabetes (T1D) meet the recommended target for hemoglobin A1c, placing them at high risk for acute and long-term complications of T1D. Thus, there is a critical need for novel approaches to improve diabetes management in adolescents with T1D. Insufficient and poor-quality sleep decrease insulin sensitivity, worsen glycemic outcomes and compromise executive function in adolescents, reducing their ability to effectively manage T1D. In other populations, sleep disturbances are linked to reduced brain matter integrity and to novel cerebrospinal fluid glymphatic flow. The glymphatic system is a recently characterized brain-wide interstitial fluid drainage pathway that enables metabolic waste clearance from the brain, particularly during sleep. Glymphatic clearance occurs through a network of perivascular spaces, and dysfunction is associated with cognitive impairment. White matter integrity and perivascular fluid, a marker of glymphatic flow, can be measured through quantitative magnetic resonance imaging (MRI) methods to assess, for the first time, how disordered sleep may impact brain health in adolescents with T1D. Aim 1. Building on our pilot work in this population, we will evaluate the effects of a sleep-promoting intervention for adolescents (age 11-17) with T1D on sleep duration and timing via a randomized controlled trial. Our central hypothesis is that adolescents randomized to the Sleep Coach intervention will exhibit significantly longer sleep duration and reduced sleep variability as compared to those who receive enhanced usual care. Aim 2: We will evaluate the effects of a sleep-promoting intervention on executive function and glycemic outcomes (HbA1c, Time in Range) and diabetes management. Hypotheses: adolescents randomized to the Sleep Coach intervention will demonstrate improved executive function, improved HbA1c and Time in Range and better diabetes management, as assessed by validated measures, compared to those who receive enhanced usual care. Aim 3: We will explore whether brain glymphatic flow, assessed via quantitative diffusion tensor imaging along perivascular spaces with MRI, increases among adolescents with T1D in parallel with increased sleep duration. We will also assess whether adolescents with increased glymphatic flow exhibit improved executive function skills. This exploratory aim will aid in understanding of the mechanisms by which disrupted sleep may impair cognitive function in T1D. Our multidisciplinary team includes a pediatric psychologist, a pediatric neurologist, a pediatric endocrinologist, and a pediatric neuroradiologist, an imaging physicist and a pediatric sleep expert. Our Children’s Diabetes Program serves a large, diverse population of children with T1D with a strong history of clinical research leadership and participation of youth with T1D and their families. This project has the potential to influence standards of clinical care for adolescents with...