Impact of Circulating and Tissue-specific Lipids on Vascular Function and Insulin Sensitivity in Chronic Night Shift Workers

NCT06550115 | Recruiting DMC

• 2 other identifiers: 3717R01HL168081
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

People who experience repeated bouts of circadian misalignment, such as shift workers, are at higher risk of cardiovascular disease (CVD) and Type 2 diabetes (T2D) compared to daytime workers. However, the mechanism(s) by which shift work and associated circadian misalignment increase CVD and T2D risk are unknown. This project will examine whether elevated plasma lipids are a mechanism by which circadian misalignment impairs vascular function, insulin sensitivity, glucose homeostasis and muscle lipid accumulation, which could be targeted to prevent and treat cardiometabolic disease in people who chronically experience circadian misalignment, which includes more than 20% of the US workforce.

Conditions

Circadian Rhythm Sleep Disorder of Shift Work Type; Metabolic Disease; Insulin Sensitivity; Blood Pressure

Keywords

Shift work; Sleep; Blood sugar; Metabolism; Lipids; Blood pressure

Outcome Measures

Primary Outcomes (2)

• Blood pressure via 24-hour assessments

  Four weeks of TRE during shift work will reduce 24-hour blood pressure versus Control.

  Collected during inpatient laboratory visit after 4 weeks of Control and TRE

• Insulin sensitivity via clamp

  Four weeks of TRE during shift work will improve insulin sensitivity versus Control.

  Collected during inpatient laboratory visit after 4 weeks of Control and TRE

Secondary Outcomes (2)

• Cerebrovascular reactivity via transcranial doppler

  Collected during inpatient laboratory visit after 4 weeks of Control and TRE

• Muscle lipid accumulation via lipidomics

  Collected during inpatient laboratory visit after 4 weeks of Control and TRE

Other Outcomes (1)

• 24-hour blood sampling for lipids, glucose, insulin, and vascular markers

  Collected during inpatient laboratory visit after 4 weeks of Control and TRE

Study Arms (2)

Control eating during overnight work shift

EXPERIMENTAL

For 4 weeks, participants will eat during the biological night as is typically done in night shift workers.

Behavioral: Control eating

Time-restricted eating during overnight work shift

EXPERIMENTAL

For 4 weeks, participants will refrain from eating during the biological night while maintaining the same sleep opportunity and daily energy intake and macronutrient distribution without changing 24h energy intake.

Behavioral: Time-restricted eating

Interventions

Time-restricted eating BEHAVIORAL

Night shift workers will participate in 4 weeks of fasting during the biological nighttime while remaining awake during overnight work shifts.

Also known as: Time-restricted feeding, TRF, TRE

Time-restricted eating during overnight work shift

Control eating BEHAVIORAL

Night shift workers will participate in 4 weeks of Control eating across the daytime and nighttime hours while remaining awake during overnight work shifts.

Control eating during overnight work shift

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• years old
• worked the night shift for the last 1 year or more,
• habitually sleep 5-9 hours per 24h period (night shift workers typically experience chronic insufficient sleep),
• body mass index (BMI) of 20.0 - 35.0 kg/m2 and weight stable (plus or minus 5% of current body weight in the last 6 months); sedentary to mild physical activity level (less than 2 days of planned exercise per week);

You may not qualify if:

• existing diagnosed sleep or eating disorder (e.g. obstructive sleep apnea \[OSA\], periodic limb movements of sleep \[PLMS\], narcolepsy, travel more than 1 time zone in 3 weeks before the study; anorexia nervosa, more than one food allergy to maintain flexibility in diet planning);
• following any TRE (time-restricted eating) or intermittent fasting plan in the last year;
• following any special diet plan, like paleo, keto, gluten-free or vegan, that can affect the primary lipid outcome measures in the last 6 months; any clinically significant surgical condition within the last year;
• diagnosed diabetes or cardiovascular disease

Sponsors & Collaborators

• Colorado State University: lead
• University of Colorado, Denver: collaborator
• National Heart, Lung, and Blood Institute (NHLBI): collaborator

Study Sites (1)

Colorado State University

Fort Collins, Colorado, 80523, United States

RECRUITING

Related Links

• Josiane Broussard's Bibliography

MeSH Terms

Conditions

Metabolic Diseases; Insulin Resistance

Condition Hierarchy (Ancestors)

Nutritional and Metabolic Diseases; Hyperinsulinism; Glucose Metabolism Disorders

Study Officials

• Josiane L Broussard, PhD

  Colorado State University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Josiane L Broussard, PhD

CONTACT

9704913103; josiane.broussard@colostate.edu

Ellen Lyon, MS

CONTACT

9704913103; ellen.lyon@colostate.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: July 22, 2024
• First Posted: August 12, 2024
• Study Start: March 1, 2024
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): June 1, 2029
• Last Updated: December 17, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)