The goal of this work is to conduct a randomized trial evaluating the effects of a behavioral intervention to increase sleep duration and quality for adolescents with type 1 diabetes (T1D). The impact of the sleep-promoting intervention on executive function and glycemic outcomes will be assessed. We will also explore multiple components of the recently identified central nervous system glymphatic system and evaluate how these components change and impact brain integrity and function with improved sleep.

This randomized controlled trial will assess whether a behavioral coaching intervention to improve sleep duration and quality in adolescents with type 1 diabetes will improve glucose control and executive function. We will recruit a sample of 150 adolescents with type 1 diabetes (T1D) and their caregivers at a single medical center. We plan to recruit equal numbers of boys and girls and over-enroll youth from minoritized racial and ethnic groups. After obtaining informed consent/assent and baseline data, we will randomize adolescents to the Sleep Coach condition (n=75) or the Enhanced Usual Care condition (n=75). Randomization will be computerized, and adolescents will be stratified by diabetes device use (insulin pumps, continuous glucose monitors) and age (11-14 years vs. 15-17 years). Adolescents and caregivers will complete survey measures again at 3 months, 6 months, and 12 months during regularly scheduled clinic visits. Adolescents will complete the NIH Toolbox measures of executive function at each study visit. Adolescents will be asked to wear a FitBit watch to assess sleep and complete sleep diaries at baseline and 3 months.

Participants randomized to the Sleep Coach group will be sent a binder with intervention materials for the 4 sessions. They will schedule individual phone calls with a trained member of the research team at a convenient time. The first call is expected to last 20-30 minutes, and the other calls are expected to last 10-15 minutes. Caregivers will receive an overview of the sleep intervention content, and they will be asked to support adolescents' attempts to change sleep habits.

Adolescents randomized to Enhanced Usual Care will receive diabetes education materials developed by our team for adolescents with T1D (based on publicly available materials on diabetes.org). Printed materials will be sent via mail and content will be shared via smart phone messages on the same schedule as participants randomized to the Sleep Coach intervention.

A representative group of 50 of the 150 adolescents in the study will be invited to participate in an additional study visit prior to the intervention to obtain magnetic resonance imaging (MRI) of the brain. Adolescents who agree to complete MRI of the brain will be asked to complete a follow-up visit approximately 6 months after the baseline visit, following the same protocol, and they will complete the daily sleep diary questions and share sleep data for another week.

Inclusion Criteria:

• 11-17 years of age at the time of enrollment
• Diagnosed with type 1 diabetes for ≥ 12 months
• Report insufficient sleep (< 8 hrs./night for 13-17 year-olds, <9 hrs./night for 11-12 year-olds) but have no other sleep disorders or sleep apnea
• Are not meeting the target for HbA1c (<7%)
• Able to read /speak English

Exclusion Criteria:

• Participant has other serious health conditions that interfere with diabetes management
• Optional MRI portion of the study - anything that would prevent an adolescent from receiving a high-quality MRI of the brain (metal implants or inability to hold still for an MRI which may take up to 60 minutes)

Inclusion criteria for caregivers:

• Currently living with the child (at least 50% of the time)
• Speak and read English