Melatonin in doctors and nurses working nightshifts

ISRCTN ISRCTN15529655
DOI https://doi.org/10.1186/ISRCTN15529655
EudraCT/CTIS number 2015-004106-42
Secondary identifying numbers 3-047-15
Submission date
19/02/2016
Registration date
22/02/2016
Last edited
12/08/2022
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Other
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English Summary

Background and study aims
Melatonin is a hormone produced by the brain that controls sleeping patterns. Levels peak at around 4am, and when night shift workers attempt to sleep in the daytime when melatonin levels are low, a ‘mismatch’ between melatonin levels and timing of sleep occurs. It takes several days to adapt. A ‘transcriptome’ is a collection of RNA molecules produced by a particular cell or tissue. The transcriptome can vary with the external environment, and changes in the transcriptome can tell us a lot about gene activity. Recent studies have shown that when there is a mismatch between melatonin production and sleep patterns, there are changes in the transcriptome. Night shift working has been associated with adverse health effects, which might be related to transcriptome changes. Poorer performance and alertness has been reported in night shift workers and this continues until the timing of melatonin production has changed to match sleeping patterns. Administration of melatonin has been used previously in ‘jet lag’, which is a similar situation to that of night shift workers. However, it is unknown whether taking a dose of melatonin affects transcriptome changes or if it helps sleeping patterns and work performance to recover quicker. Melatonin has an excellent safety profile and may be used as a new treatment to improve sleep patterns, improve performance and possibly correct the adverse health effects of night shift working. The aim of this study is to determine the effects of giving doses of melatonin in medical staff working night shifts, and to assess whether melatonin given before sleep time is able to improve sleep, improve alertness and affect transcriptome changes.

Who can participate?
Doctor and nurses working two series of night shifts at least 4 weeks apart

What does the study involve?
Each participant is studied twice - during one series of night shifts they take melatonin and during the other series of night shifts they take a placebo (dummy drug). The order in which they take melatonin or placebo is decided randomly. They complete questionnaires about their normal sleeping habits, their sleeping patterns during the night shift and how sleepy they feel. Participants' alertness is assessed using a computer reaction test and blood samples are taken to measure transcriptome changes. Participants also wear a wristband monitor during sleep periods to obtain data on their sleeping patterns and restlessness.

What are the possible benefits and risks of participating?
The study will tell us whether melatonin might help people undertaking night shifts adapt more quickly to a new sleeping pattern and whether taking melatonin affects the transcriptome changes which have been previously described, which may improve adverse health outcomes.

Where is the study run from?
University of Aberdeen/NHS Grampian (UK)

When is the study starting and how long is it expected to run for?
April 2016 to March 2018

Who is funding the study?
Chief Scientist Office

Who is the main contact?
Prof Helen Galley

Contact information

Prof Helen Galley
Scientific

Institute of Medical Sciences
Foresterhill
Aberdeen
AB25 2ZB
United Kingdom

ORCiD logoORCID ID 0000-0002-9517-0074

Study information

Study designRandomised double-blind placebo-controlled crossover pilot study
Primary study designInterventional
Secondary study designRandomised cross over trial
Study setting(s)Hospital
Study typeQuality of life
Participant information sheet Not available in web format, please use the contact details below to request a patient information sheet
Scientific titleMelatonin In Doctors and nurses working NIGHTshifts (MIDNIGHT): a randomised double-blind placebo-controlled crossover pilot study
Study acronymMIDNIGHT
Study hypothesisThe aim of this pilot study is to determine the effects of exogenous melatonin administration compared with placebo in medical staff working night shifts on the intensive care unit.
Ethics approval(s)North of Scotland research ethics committee 2, 17/02/2016
ConditionDoctors and nurses working nightshifts
InterventionSubjects will take 6mg Circadin (slow release melatonin) or a matching placebo on three consecutive days during night shift working on two separate series of night shifts at least 4 weeks apart.
Intervention typeDrug
Pharmaceutical study type(s)
PhasePhase II
Drug / device / biological / vaccine name(s)Circadin (melatonin)
Primary outcome measureThe primary endpoint is successful completion of the trial, defined as recruitment, randomisation and protocol completion of 25 individuals i.e., both arms of the crossover design.
Secondary outcome measures1. Determination of drop out, non completion and retention rate (end of trial)
2. Differential gene expression (blood samples on Day 1 before shift, and end of shifts series on Day 4)
3. Differential gene expression between placebo and active arms (blood samples Day 4 after each shift series)
4. Serum interleukin-6 and tumour necrosis factor alpha levels (blood samples on Day 1, and end of shifts series on Day 4)
5. Serum IL-6 and TNFalpha levels after placebo and active arms (blood samples Day 4 after each shift series)
6. Serum melatonin and 6-hydroxymelatonin sulphate levels at each time point (blood samples on Day 1 before shift, and end of each shift for shift series)
7. Verran and Snyder-Halpern sleep scale, Epworth sleepiness scale, data from wristband activity monitor (VSH before each shift, ESS before, during and after each shift. Activity monitoring during each sleep period)
8. Psychomotor vigilance task, double digit addition test (PVT and DDAT before and after each shift)
9. Usual sleep habits and owl-lark questionnaires (before randomisation)
10. Questionnaire about trial (trial end)
11. Focus group about trial (trial end - requires additional consent)
Overall study start date01/04/2016
Overall study end date30/03/2018

Eligibility

Participant type(s)Health professional
Age groupAdult
SexBoth
Target number of participants32
Total final enrolment25
Participant inclusion criteria1. Either sex
2. Non-smokers
3. Not taking regular medicine
4. No health complaints
5. Doctor or nurse working two series of night shifts at least 4 weeks apart
Participant exclusion criteria1. Pregnant or trying to get pregnant
2. Breastfeeding
3. Use of sedatives, hypnotics, herbal remedies, sleeping pills
4. Taking medication except oral contraceptives
Recruitment start date01/04/2016
Recruitment end date30/08/2017

Locations

Countries of recruitment

  • Scotland
  • United Kingdom

Study participating centre

University of Aberdeen/NHS Grampian
Research Governance Office
Foresterhill House Annexe
Foresterhill
Aberdeen
AB25 2ZB
United Kingdom

Sponsor information

University of Aberdeen/NHS Grampian (UK)
University/education

Research Governance Office
Foresterhill House Annexe
Foresterhill
Aberdeen
AB25 2ZB
Scotland
United Kingdom

ROR logo "ROR" https://ror.org/016476m91

Funders

Funder type

Government

Chief Scientist Office
Government organisation / Local government
Alternative name(s)
CSO
Location
United Kingdom

Results and Publications

Intention to publish date30/03/2019
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot expected to be made available
Publication and dissemination planNot provided at time of registration.
IPD sharing planNot provided at time of registration

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Basic results 12/03/2019 No No
Results article results 27/08/2020 17/11/2020 Yes No
Protocol file version 4.0 16/06/2016 12/08/2022 No No

Additional files

ISRCTN15529655_BasicResults_12Mar2019.pdf
31771 MIDNIGHT protocol V4.0 16June2016.pdf

Editorial Notes

12/08/2022: Uploaded protocol (not peer-reviewed) as an additional file.
17/11/2020: Publication reference and total final enrolment number added.
12/03/2019: The basic results of this trial have been uploaded as an additional file.
18/07/2018: The recruitment end date was changed from 30/03/2018 to 30/08/2017
23/10/2017: Internal review.