ImpaCt Of Shiftwork on METabolic Flexibility and Skeletal Muscle Clocks (COMET)

AdventHealth Translational Research Institute

Status

Enrolling

Conditions

Metabolic Health

Treatments

Other: Morningness-Eveningness Questionnaire

Other: Whole Room Calorimeter

Other: Mixed-Meal Tolerance Test (MMTT)

Other: Serial Blood Sampling

Procedure: Muscle Biopsy

Other: Core Body Temperature

Study type

Observational

Funder types

Other

Identifiers

NCT05820490

1993997

Details and patient eligibility

About

The purpose of this study is to determine the impact of real-world shiftwork on metabolic flexibility.

Enrollment

45 estimated patients

Sex

All

Ages

21 to 45 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

Age 21-45 yrs
Employed as a healthcare worker in either dayshift (N=15) or nightshift work (N=30).
Nightshift is defined as 12 months of consecutive nightshift work, who had 10 or more nightshifts per month (6 h between 10 PM and 8 AM, with no shift duration > 12 h).
Dayshift is defined as 12 months of consecutive dayshift work, who had 10 or more dayshifts per month (6h between 8 AM and 10 PM, with no shift duration > 12 h).
Weight Stable (+/- 3 kg over past 6 months)
BMI between 18.5-29.9 kg/m2
Understands the procedures and agrees to participate by giving written informed consent
Willing and able to comply with scheduled visits, laboratory tests, and other study procedures including
Only low to moderate caffeine users (<500 mg/day, or up to approximately 5 cups [1 cup=8 ounces] of coffee/day.

Exclusion criteria

Acute or chronic medical conditions or medication that would contraindicate participation in the research testing or could potentially affect metabolic function including, but not limited to:
History or presence of cardiovascular disease (unstable angina, myocardial infarction or coronary revascularization within 6 months, presence of cardiac pacemaker, implanted cardiac defibrillator)
Type 1 or Type 2 diabetes mellitus
Obesity (BMI ≥ 30 kg/m2)
Bleeding and clotting disorders
Uncontrolled hypertension (BP >160 mmHg systolic or >100 mmHg diastolic)
Acute or chronic infections (such as TB, HIV, or Hepatitis)
Renal insufficiency or nephritis (eGFR<60), nephritis, or chronic kidney disease
Chronic obstructive pulmonary disease
Thyroid dysfunction (suppressed TSH, elevated TSH <10 µIU/ml if symptomatic or elevated TSH >10 µIU/ml if asymptomatic)
Liver disease (liver function tests > 2 x normal; including nonalcoholic steatohepatitis [NASH] and non-alcoholic fatty liver disease [NAFLD])
Diagnosed or being treated for sleep disorders
History of Cushing's disease or syndrome
Pregnant or nursing females or females less than 6 months postpartum from the scheduled date of collection
Anemia (hemoglobin <12 g/dl in men, <11 g/dl in women) during screening
Participation in studies involving investigational drug(s) within 30 days prior to Screening
Gastrointestinal disorders (including inflammatory bowel disease or malabsorption, swallowing disorders, suspected or known strictures, fistulas or physiological/mechanical GI obstruction, history of gastrointestinal surgery, Crohn's disease or diverticulitis)
Past or present history of psychiatric disease, including major depressive illness or bipolar disorder, as well as claustrophobia since part of the protocol will involve being confined to a small room for whole-body indirect calorimetry
Unwilling or unable to eat foods provided in study procedures
Nickel allergy
Lidocaine allergy
Any malignancy not considered cured, except basal cell carcinoma and squamous cell carcinoma of the skin (a participant is considered cured if there has been no evidence of cancer recurrence in the previous 5 years)
Use of antibiotics within 3 months of screening
Illicit drug use (negative tests at screening)
Regular smoking or regular nicotine use of any kind including chewing tobacco, snuff and vaping
History of regular alcohol consumption exceeding 7 drinks/week for female participants or 14 drinks/week for male participants (1 drink = 5 ounces [150 mL] of wine or 12 ounces [360 mL] of beer or 1.5 ounces [45 mL] of hard liquor) within 6 months before screening.
Excessive caffeine use (>500 mg/day, or exceeding 5 cups [1 cup= 8 ounces] of coffee/day)
Blood donation (excluding plasma donations) of approximately 1 pint (500 mL) or more within 56 days prior to Screening (participants may not donate blood any time during the study, through the final study day)
Presence of any condition that, in the opinion of the Investigator, compromises participant safety or data integrity or the participant's ability to complete study days.
More than 1-day a week of intentional exercise

Excluded medications include, but are not limited to:

Any prescription medication or other drug that may influence metabolism (e.g. diet/weight-loss medication, psychiatric medications, corticosteroids, or other medications at the discretion of the PI and/or study team)
Medications that strongly impact bleeding, clotting, bruising, or platelets (e.g. blood thinner prescription medications)
Recent change to medication and/or dosing in the past 3 months
Chronic use of aspirin or other non-steroidal anti-inflammatory drugs, including COX-2 inhibitors