Effect of Melatonin on Sleep Patterns of Resident Trainees During Night Float Shift

Anesthesiology residency requires extended and overnight shifts, which may negatively impact the quantity and quality of sleep.

Previous studies have investigated the effect of night float shift work on anesthesiology resident sleep and performance and demonstrated that total sleep quantity and time spent in deep and rapid eye movement (REM) sleep were significantly reduced during night float and did not return to baseline after 3 nights of recovery.

Melatonin is a hormone produced by the pineal gland, which regulates the circadian rhythm that governs sleep. Exogenous melatonin may be used as a sleep aid and is available over the counter in the United States. Melatonin is effective in realigning the circadian rhythm disorder caused by night shift work and increasing sleep duration; however, melatonin's effect on improving sleep in resident trainees has not been investigated. The investigators propose a prospective double-blinded randomized control trial to investigate the effect of melatonin on sleep quantity and quality in resident physicians assigned to a night float system.

Study Overview

• Status: Recruiting
• Conditions: Sleep Disorders, Circadian Rhythm
• Intervention / Treatment: Other: Placebo; Dietary supplement: Melatonin

Detailed Description

Residents in Post-Graduate Years 1-7 enrolled in residency programs with a night float system (anesthesiology, general surgery, obstetrics and gynecology, general medicine, and pediatrics) will be invited to participate in the study. A clinical study coordinator will assist in obtaining informed consent. After informed consent is obtained, participants will be randomized to receive either 3 mg melatonin or a matching placebo control. Medications will be prepared and randomization performed by the University of Virginia Pharmacy. Both participants and study coordinators will be blinded to the treatment group. Participants will be provided with a 12-day supply of medication at the start of the night float week. They will be instructed to take one capsule at least 20 minutes prior to going to bed at night or during the day after completing their night float shift. Subjects will be given a portable electroencephalography (EEG) monitor (ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH))12 and will be shown how to apply the machine, monitor its functionality, and troubleshoot minor issues. They will be asked to wear the device for 2-3 nights of baseline sleep, 5-6 days of sleep during night float, and 3-4 nights of recovery following night float, for a total of 12 consecutive days. Baseline sleep data will serve as a control for each subject. EEG data collected will include: Light Sleep, Deep Sleep, REM, Arousals, Total Sleep Time, Sleep Efficiency, Latency to Persistent Sleep, Wake After Sleep Onset, Total Deep Sleep, Total REM Sleep, and Time Out of Bed. Data from two different night float periods separated by at least 2 weeks will be collected (one-week melatonin and one-week placebo in random order). Residents will also be asked to complete a daily questionnaire assessing daytime sleepiness (Epworth Sleepiness Scale) and the use of caffeine or other stimulants.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Keita Ikeda, PH.D.; Phone Number: 9195931174; Email: ki2d@uvahealth.org
• Study Contact Backup: Name: Emily Chuang, MA; Phone Number: 7575348912; Email: QGZ2TK@uvahealth.org

Study Locations

• United States
  • Virginia
    • Charlottesville, Virginia, United States, 22908-0710
      • Recruiting
      • University of Virginia
      • Contact: Keita Ikeda, PhD; Phone Number: 9195931174; Email: ki2d@uvahealth.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Post-Graduate Year 1-5
• Current enrollment in anesthesiology, general surgery, obstetrics and gynecology, general medicine, or pediatrics residency at the Unversity of Virginia

Exclusion Criteria:

• Current use of sleep aids
• Diagnosed sleep disorder
• History of a pacemaker or other medical device.
• pregnant or breast-feeding females
• Bleeding disorders
• Depression
• High blood pressure
• Seizure disorders
• History of transplant on immunosuppression therapy.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Melatonin group; These subjects will receive melatonin	Dietary supplement: Melatonin; Melatonin
Placebo Comparator: Placebo group; These subjects will receive placebo	Other: Placebo; Placebo control

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Sleep Time (TST)	Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Light Sleep	Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks
Deep Sleep	Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks
Rapid Eye Movement Sleep	Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks
Latency to Persistent Sleep (LPS)	Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks
Wake after Sleep Onset (WASO)	Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks
Sleep Efficiency (SE)	monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)	2 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Epworth Sleepiness Scale	Score 0-24 (Interpretation: 0-7: Unlikely to be abnormally sleepy. 8-9: Average amount of daytime sleepiness. 10-15: May be excessively sleepy depending on the situation. Consider seeking medical attention. 16-24: Excessively sleepy, consider seeking medical attention.)	2 weeks

Collaborators and Investigators

• Sponsor: University of Virginia
• Investigators: Principal Investigator: Lauren Dunn, MD PHD, University of Virginia

Study record dates

Study Major Dates

• Study Start (Actual): May 30, 2022
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 30, 2028

Study Registration Dates

• First Submitted: January 6, 2023
• First Submitted That Met QC Criteria: January 18, 2023
• First Posted (Actual): January 27, 2023

Study Record Updates

• Last Update Posted (Actual): May 4, 2026
• Last Update Submitted That Met QC Criteria: April 27, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Mental Disorders; Sleep Wake Disorders; Dyssomnias; Chronobiology Disorders; Occupational Diseases; Sleep Disorders, Circadian Rhythm; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Indoles; Tryptamines; Melatonin
• Other Study ID Numbers: HSR210118

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No