Impact of Sleep Extension in Adolescents

Study Overview
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Brief Summary
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Many teenagers do not get enough sleep. Obesity and diabetes are increasing in teenagers as well. This study plans to learn more about sleep and insulin resistance (insulin not working) in teenagers, and how these things may be related depending on sleep. This is important to know so that the investigators understand how sleep may play a role in health conditions like extra weight gain (increased food intake and less physical activity) and diabetes. To answer this question, the investigators plan to enroll teenagers who get <7 hours of sleep on school nights and measure changes in insulin sensitivity and dietary intake after a week of typical sleep (sleeping on their normal school schedule) and a week of longer sleep (spending 1+ hour longer in bed each night).

Official Title
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Impact of Sleep Extension on Insulin Sensitivity and Dietary Intake in Adolescents

Conditions
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Insulin Sensitivity, Sleep, Dietary Habits

Intervention / Treatment
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* Behavioral: Sleep Extension


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: High school students between the age of 14-19 years have typically insufficient sleep, defined by ≤ 7 hours per night on school days BMI 5th-84th percentile for age and sex habitually sedentary (< 3 hours of regular physical activity per week) Tanner stage 4 or 5, based on breast development for girls and testicular size for boys. Exclusion Criteria: Any medications that affect IR or sleep (e.g., metformin, stimulants, atypical antipsychotics, current use of oral steroids) regular use of melatonin or other sleep aids a prior diagnosis of a sleep disorder (e.g. insomnia, delayed sleep phase syndrome, obstructive sleep apnea) Type 2 diabetes or prediabetes IQ<70 or severe mental illness that may impact sleep or ability to consent/assent (e.g., schizophrenia, psychotic episodes) teens not enrolled in a traditional high school academic program (e.g., home school students) schedules that would preclude participants from adhering to the sleep manipulation (e.g. night shift employment) travel across more than two time zones in the 2 weeks prior to the study.

Ages Eligible for Study
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Minimum Age: 14 Years
Maximum Age: 19 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Typical Sleep<br>All participants will sleep for 6 nights (Sunday - Thursday) in the home environment per their usual school schedule. | |
| Experimental: Sleep Extension<br>Participants will be prescribed a sleep schedule that allows them to obtain 1 hour more time in bed compared to Typical Sleep. For participants completing the study September 2021 and later, they will also be instructed to take exogenous melatonin (500mcg) and maintain dim light conditions 2 hours before bedtime, and use light glasses for 30 minutes in an upright position after waking in the morning (Sleep Extension + Circadian Manipulation). | Behavioral: Sleep Extension<br>* Participants will be asked to increase time in bed at least 1 hour more than baseline<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Insulin Sensitivity | Insulin sensitivity assessed two times with an insulin-modified intravenous glucose tolerance test. | 2 weeks after Baseline and 7 weeks after Baseline | 
| Change in Sleep Duration & Timing | Assessed three times with a wrist-worn Actigraphy | At Baseline, 1 week after Baseline, and 6 weeks after Baseline | 
| Change in Physical activity | Assessed three times with a triaxial thigh-worn ActivPal | At Baseline, 1 week after Baseline and 6 weeks after Baseline | 
| Change in Dietary Intake | Participants will be asked to complete diet diaries two times for 3 days during each sleep condition (prior to each overnight assessment), listing all food and drink consumed, estimated portion size, and timing of consumption. | 1 week after Baseline and 6 weeks after Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in glycemic variability | Assessed two times with a continuous glucose monitor | 2 weeks after Baseline and 7 weeks after Baseline | 
| MTNR1B rs10830963 SNP | Genotyping will be conducted on saliva samples | 2 weeks after Baseline |