Effect of Sleep Extension on Ceramides in People With Overweight and Obesity

Biomarkers of Habitual Short Sleep and Related Cardiometabolic Risk

The overall goal is to determine how a sleep extension intervention (increasing time in bed) in individuals who maintain less than 6.5 hours sleep per night affects their plasma ceramides and insulin sensitivity. Participants will undergo a randomized controlled trial, with sleep extension (intervention) and healthy lifestyle (control) groups. The sleep extension is designed to increase participant's time in bed by 2 hours per night. Alternatively, the control group will receive basic health information (e.g., physical activity, goal setting, and nutrition when eating out).

A randomized controlled trial with real-world sleep extension in adults with overweight and obesity who habitually obtain short sleep duration will be conducted. Group allocation will be 1:1 and research staff and participants will be blinded until the conclusion of the baseline segment. The sleep extension group will receive counseling and instruction to increase nightly time in bed by 2 hours per night. Participants randomized to control will maintain their habitual sleep habits in their home environment. The intervention segment will last 8 weeks regardless of group assignment. Both groups will have equal contact time with the study team.

Prior to enrollment participants will complete a clinical overnight sleep disorders screening. Baseline consists of an ~1-week ambulatory real-world monitoring segment. Following baseline, participants will be randomized 1:1 to either the sleep extension or control group for 8 weeks at home (intervention segment). Throughout the study, sleep duration will be monitored using an actiwatch wrist-device and a daily electronic sleep log. Following the baseline and intervention segments participants will complete rigorous overnight laboratory visits to assess plasma ceramides (targeted metabolomics assay) and insulin sensitivity (hyperinsulinemic-euglycemic clamp).

Inclusion Criteria:

1. Age: 18-45 years old; equal numbers of men and women
2. Body mass index (BMI): 27.5-34.9 kg/m2
3. Sleep Habits: habitual self-reported average total sleep time (TST) <6.5 hours per night for prior 6 months

Exclusion Criteria:

1. Clinically diagnosed sleep disorder or major psychiatric illness
2. Evidence of significant organ dysfunction or disease (e.g., heart disease, kidney disease)
3. Clinically diagnosed diabetes or fasting plasma glucose ≥126 mg/dL or HbA1c ≥6.5%
4. Use of prescription drugs or substances known to influence sleep or glucose metabolism, or anticoagulant medications.
5. Cancer that has been in remission less than 5 years
6. Pregnant/nursing, experiencing menopause or post-menopausal
7. Shift-work: current or history of within last year
8. Weight change: >10% of body weight over prior six months
9. Current enrollment in weight loss or physical activity program like the Diabetes Prevention Program
10. Currently smoking
11. Alcohol intake>14 drinks per week or >3 drinks per day