Clinical Trial: Effects of Hydrocortisone, Melatonin, and Placebo on Jet Lag
Study Status: Completed
Recruit Status: Completed
Study Type: Interventional
Official Title: The Effects of Hydrocortisone, Melatonin, and Placebo on Symptoms of Jet Lag
Brief Summary:
This study will examine the effects of cortisol (hydrocortisone), melatonin, a combination of cortisol and melatonin, and placebo (an inactive substance) on jet lag symptoms. Jet lag is a term used to describe symptoms people commonly experience after rapid travel across several time zones. The cause of jet lag is not known, but various hormones, including cortisol and melatonin, have a day-to-night pattern of secretion and play a role in maintaining the body's internal rhythms. This study will test whether taking cortisol, melatonin, or both can help re-establish the body's day-night cycle and result in less jet lag.
People between 18 and 65 years of age who are planning a non-stop eastward flight with the following characteristics may be eligible for this study:
- Crossing six to eight time zones (6 to 8 hours difference between Eastern Standard Time and the destination)
- Destination between 30 and 50 latitudes (approximately Cairo to London)
- Evening flight (5 PM to midnight) with morning arrival
- Remaining abroad at least 4-10 days
Candidates must have a body mass index (BMI) between 20 and 30 kg/M (not too thin and not overweight) and must not be taking medicines that affect sleep or cortisol or melatonin levels. Prospective participants are screened with a medical history, blood tests, and check of blood pressure, height, and weight.
Pre-flight Procedures
Participants keep a sleep journal 3 days before the flight. For 1 day within 3 days of the flight they fill out jet lag and sleepiness questionnaires and collect morning and bedtime
Detailed Summary:
Jet lag resulting from rapid flight across several time zones is a common complaint of travelers. The symptoms of jet lag are primarily described as daytime sleepiness, fatigue, and impaired mental efficiency and can also include weakness and irritability. It is considered to be due to the desynchronization between the internal circadian rhythm and the new local day-night cycle at the traveler's destination. A means of rapidly resynchronizing the circadian rhythm to the local time would benefit people who suffer severely from this syndrome.
What actually underlies jet lag is a question that has not been fully answered. Various endogenous hormones, including cortisol and melatonin, have a natural circadian rhythmicity and play a role in maintaining the body's internal clock. Cortisol is produced by the hypothalamic- pituitary-adrenal axis in a circadian manner and in response to stress. Normal cortisol has a diurnal rhythm with a maximum level in the morning and a nadir during the night. While a time shift does not change the total daily amount of cortisol that is secreted, the temporal organization of the cortisol secretions is disrupted and the circadian rhythm does not re-entrain for several days. Thus, the first few mornings in a new time zone can be considered relatively cortisol-deficient because the traveler does not experience the peak of cortisol at the time of awakening. Taking exogenous glucocorticoids at the proper time may help re-entrain the circadian rhythm faster and result in less jet lag.
Melatonin is a hormone that is secreted nocturnally by the pineal gland. Exposure to bright light diminishes its release while darkness triggers it. A recent meta-analysis has shown that taking melatonin can alleviate symptoms of jet lag.
The aim of the present study is an
Sponsor: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Current Primary Outcome: Fatigue score
Original Primary Outcome:
Current Secondary Outcome:
Original Secondary Outcome:
Information By: National Institutes of Health Clinical Center (CC)
Dates:
Date Received: November 23, 2004
Date Started: November 22, 2004
Date Completion:
Last Updated: April 20, 2017
Last Verified: July 29, 2016
