Recruiting

Observational Study

Sponsor:

Johns Hopkins University

Code:

NCT06507722

Conditions

PreDiabetes

Overweight

Impaired Glucose Tolerance

Eligibility Criteria

Sex: All

Age: 18 - 23

Healthy Volunteers: Accepted

Interventions

Timing of OGTT

Timing of Standardized Meal

Study Details

Brief summary:

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.

Conditions

PreDiabetes

Overweight

Impaired Glucose Tolerance

Study ID

NCT06507722

Start date

Feb 25, 2025

Status verified date

May, 2026

Completion date

Jan 31, 2030

Anticipated

Primary completion date

Dec 31, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 23

Healthy Volunteers: Accepted

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.

Study Design

Enrollment

70 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Prevention

Interventions and Outcome Measures

Arms

other: Cohort A - Late Chronotype first, then alternate

Sleep onset after 2am

other: Cohort B - Non-late Chronotype first, then alternate

Sleep onset before 11pm

Interventions

Timing of OGTT

In Aim 1, timing of oral glucose tolerance test will be altered.

Timing of Standardized Meal

In Aim 2, timing of a standardized meal will be altered.

Primary outcome measure

  • 2-Hour Difference in Glucose [ Time Frame: Day 4 and Day 11 of Aim 1 derived from OGTT ]
  • Insulin Sensitivity (by Oral Minimal Model) [ Time Frame: Day 4 and Day 11 of Aim 1 derived from 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 ]

Central Contacts and Locations

Central contacts

Talia Hitt, MD/MPH/MSHP

860-324-0072thitt2@jhmi.edu

Locations

Johns Hopkins School of Medicine

Recruiting

Baltimore, Maryland, United States, 21287

Contacts

Talia Hitt, MD/MPH/MSHP

860-324-0072thitt2@jhmi.edu

More Information

Sponsor

Johns Hopkins University

Last update posted

May 11, 2026

Last verified

May, 2026

Keywords

  • chronotype
  • sleep

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Johns Hopkins University on 2026-05-11.