NCT06507722 · Johns Hopkins University
Night Owl Metabolism
What this study is about
The proposed study uses a novel and rigorous randomly assigned cross-over study design in youth (18-23y) with late and non-late chronotype (n=35 per group) to assess the glycemic effect of "aligning" an taken by mouth glucose tolerance test (OGTT) or first-meal of day to a subject's chronotype.
View original scientific description
The proposed study uses a novel and rigorous randomized cross-over study design in youth (18-23y) with late and non-late chronotype (n=35 per group) to assess the glycemic effect of "aligning" an oral glucose tolerance test (OGTT) or first-meal of day to a subject's chronotype. Both groups will undergo 2 OGTTs (aligned and mis-aligned with chronotype) to compare glucose tolerance and insulin sensitivity within-subject (primary outcome) and between groups (Aim 1). Then, youth will also undergo two standardized meals (aligned and mis-aligned with chronotype) while wearing continuous glucose monitoring to compare post-prandial glucose excursions within-subject and between groups (Aim 2). A pilot Exploratory Aim 3 (n=12 per group) will investigate delayed melatonin patterns under dim-light as a potential pathophysiologic mechanism behind abnormal glucose tolerance in youth with late chronotype on morning OGTTs.
Interventions
DIAGNOSTIC_TEST
Timing of OGTT
In Aim 1, timing of oral glucose tolerance test will be altered.
BEHAVIORAL
Timing of Standardized Meal
In Aim 2, timing of a standardized meal will be altered.
Primary outcome measures
2-Hour Difference in Glucose
Time frame: Day 4 and Day 11 of Aim 1 derived from OGTT
Within-subject difference in 2-hour glucose after glucose ingestion on OGTT between early and late OGTT (primary analysis) in the late chronotype group and secondary analysis will be between group differences between early and late OGTT.
Insulin Sensitivity (by Oral Minimal Model)
Time frame: Day 4 and Day 11 of Aim 1 derived from OGTT
Within-subject difference in insulin sensitivity (derived from oral Minimal Model) between early and late OGTT (primary analysis) in the late chronotype group and secondary analysis will be between group differences between early and late OGTT.
2-hour Incremental Area Under the Curve (iAUC) for glucose
Time frame: Day 1 and Day 8 of Aim 2 during post-prandial period following each standardized meal
Within-subject difference in iAUC for glucose from continuous glucose monitor between early and late Meal (primary analysis) in the late chronotype group and secondary analysis will be between group differences between early and late Meal.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Overweight similar to (BMI ≥ 85th percentile but \<95th percentile for age and sex per Centers for Disease Control and Prevention growth curves (as Centers for Disease Control and Prevention growth curves contain ages ≤ 20y; if ages 21-23 years, the BMI ≥ 85th and \<95th percentile equivalents for a 20-year-old will be used))
- Post-pubertal
- Normal sleep duration (avg. \>7 hours of sleep per night)
- Social jetlag (difference between weekend and weekday sleep) of \< 2 hours.
Exclusion criteria
- Known diabetes, sleep disorders, major organ system illness, pregnancy, or genetic syndrome
- Medication use known to affect insulin sensitivity, glucose tolerance, or circadian rhythm
- Screening high risk for obstructive sleep apnea
- Night shift work.
Where
- Baltimore, Maryland
Collaborators
Lawson Wilkins Pediatric Endocrine Society, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), DexCom, Inc.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 11, 2026 · Source of record for eligibility and locations