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Trial registered on ANZCTR


Registration number
ACTRN12615001107516
Ethics application status
Approved
Date submitted
15/07/2015
Date registered
21/10/2015
Date last updated
1/12/2016
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effects of night eating during simulated shift work on metabolism, cognitive performance and mood in healthy adult males
Scientific title
In healthy adult males, what is the impact of eating at night (compared to not eating at night) on metabolism, cognitive performance and mood during simulated night shift?
Secondary ID [1] 287092 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cognitive performance 295616 0
Metabolic health 295617 0
Condition category
Condition code
Diet and Nutrition 295893 295893 0 0
Other diet and nutrition disorders
Mental Health 295894 295894 0 0
Studies of normal psychology, cognitive function and behaviour
Metabolic and Endocrine 295895 295895 0 0
Normal metabolism and endocrine development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
A simulated shift work protocol, with one 8h night time baseline sleep, followed by 4 consecutive days of simulated shift work (sleep from 10:00-16:00 each day), and an 8h night time recovery sleep on day 6. During simulated night shift (22:00-0:00) participants completed a number of performance based assessment tasks including simulated driving and a neural behavioural test battery.

Meals: morning 07:00 (toast, cereal etc), late afternoon 19:00 (sandwiches etc) and night 01:30 (mixed dishes, salad, veg etc). The diet is a standardised diet typical of the Australian diet. The energy content of the meals was based on individual daily dietary energy requirements (kJ) calculated using the Harris Benedict equation with a light/sedentary activity level (laboratory condition). All food provided was weighed and recorded pre and post consumption. Participants were allowed access to water ad libitum.

During the protocol participants were supervised by at least two research assistants at all times. A combination of actigraphy watches and polysomnography were used to monitor sleep. Physical activity was kept to a minimum in the laboratory.
Intervention code [1] 292337 0
Behaviour
Intervention code [2] 292779 0
Lifestyle
Comparator / control treatment
A simulated shift work protocol , with one 8h night time baseline sleep, followed by 4 consecutive days of simulated shift work (sleep from 10:00-16:00 each day), and an 8h night time recovery sleep on day 6. During simulated night shift (22:00-06:00) participants completed a number of performance based assessment tasks including simulated driving and a neural behavioural test battery.

Meals: morning 07:00 (toast, cereal etc), mid-morning 09:30 and mid-afternoon 14:00 (fruit, muffins, crackers etc) and night 19:00 (mixed dishes, salad, veg etc). The diet was a standardised diet typical of the Australian diet. The energy content of the meals was based on individual daily dietary energy requirements (kJ) calculated using the Harris Benedict equation with a light/sedentary activity level (laboratory condition). All food provided was weighed and recorded pre and post consumption. Participants were allowed access to water ad libitum.

During the protocol participants were supervised by at two research assistants at all times. A combination of actigraphy watches and polysomnography were used to monitor sleep. Physical activity was kept to a minimum in the laboratory.
Control group
Active

Outcomes
Primary outcome [1] 295566 0
Serum samples for glucose analysis will be collected to assess markers of metabolic risk at regular intervals pre and post breakfast.
Timepoint [1] 295566 0
-15, 0 minutes pre- and 15, 30, 60, 90 and 120 minutes post-breakfast on days 1 (baseline), 4 and 5 (recovery).
Primary outcome [2] 296327 0
- Serum samples for insulin analysis will be collected to assess markers of metabolic risk at regular intervals pre and post breakfast.
Timepoint [2] 296327 0
-15, 0 minutes pre- and 15, 30, 60, 90 and 120 minutes post-breakfast on days 1 (baseline), 4 and 5 (recovery).
Primary outcome [3] 296328 0
Serum samples for free fatty acid analysis will be collected to assess markers of metabolic risk at regular intervals pre and post breakfast.
Timepoint [3] 296328 0
-15, 0 minutes pre- and 15, 30, 60, 90 and 120 minutes post-breakfast on days 1 (baseline), 4 and 5 (recovery).
Secondary outcome [1] 315862 0
Cognitive functioning, assessed by a battery of cognitive tests including: psychomotor vigilance task (vigilant attention task), and Digit-symbol substitution task
Timepoint [1] 315862 0
Every 3-hours during wake periods on Day 2- Day 5. An additional time point will be added on Day 1 (baseline) and Day 6 (post recovery sleep).
Secondary outcome [2] 315863 0
Markers of sleep quality will be assessed using polysomnography. Some markers of sleep quality are total sleep time, sleep efficiency and slow wave sleep.
Timepoint [2] 315863 0
Day 1 (baseline), Day 4 and Day 6 (recovery)
Secondary outcome [3] 317725 0
Mood, assessed by a battery of cognitive tests including: Likert type scales and PANAS
Timepoint [3] 317725 0
Every 3-hours during wake periods on Day 2- Day 5. An additional time point will be added on Day 1 (baseline) and Day 6 (post recovery sleep).

Eligibility
Key inclusion criteria
Males, aged 18-45 years, BMI normal to overweight (20-29kg/m2), non-smoker, low alcohol (less than or equal to 2 standard drinks/ day) and caffeine consumption (less than or equal to 2 cups/ day), normal sleep/wake pattern (habitual sleep duration between 7-8 hours a night), stable weight over the preceding 3 months, competent written and spoken English.
Minimum age
18 Years
Maximum age
45 Years
Gender
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
Subjects who report one or more of the following: habitual napping (more than 1 per week), score of less than 31 or more than 69 in the morningness- eveningness questionnaire, significant depression or physical illness, established using clinical history and Beck Depression Inventory (score equal to or more than 14), food difficulties (example: gluten intolerance or restrained eaters) measured by clinical history, use of medications, including injected, topical or inhaled glucocorticoids, previous shift work history, sleep disorders, history of medical conditions; cardiovascular disease, neurological disorder, kidney disease, liver disease, clinically significant values (as determined by the reviewing study physician) for any hematology or chemistry parameter. Reviewing study licensed physician may opt to repeat any clinically significant tests and include volunteers whose repeat test values are not clinically significant, currently taking corticosteroid or anti-inflammatory medications.

Study design
Purpose of the study
Prevention
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Mixed effects regression will be used to investigate differences in glucose response to breakfast and cognitive performance over the simulated shift work protocol. Models will specify dependent variables of glucose metabolism following breakfast and response speed and accuracy for cognitive measures. Models will specify within subjects factors of day (baseline/ simulated night work/recovery) and a random intercept of subject ID in order to appropriately take into account within and between subjects. This a pilot study designed to investigate the sample size required to achieve statistical significance.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 291656 0
University
Name [1] 291656 0
University of South Australia
Address [1] 291656 0
Centre for Sleep Research
University of South Australia
Playford Building, Frome Road
City East Campus
Adelaide SA 5000
Australia
Country [1] 291656 0
Australia
Primary sponsor type
Individual
Name
Dr Siobhan Banks
Address
Centre for Sleep Research
University of South Australia
Playford Building, Frome Road
City East Campus
Adelaide SA 5000
Australia
Country
Australia
Secondary sponsor category [1] 290322 0
Individual
Name [1] 290322 0
Ass. Prof Alison Coates
Address [1] 290322 0
Division of Health Science
University of South Australia
City East Campus
GPO Box 2471
Adelaide SA 5001
Australia
Country [1] 290322 0
Australia
Secondary sponsor category [2] 290323 0
Individual
Name [2] 290323 0
Ass. Prof Jill Dorrian
Address [2] 290323 0
Centre for Sleep Research
University of South Australia
Playford Building, Frome Road
City East Campus
Adelaide SA 5000
Australia
Country [2] 290323 0
Australia
Secondary sponsor category [3] 290324 0
Individual
Name [3] 290324 0
Ms. Crystal Grant
Address [3] 290324 0
Centre for Sleep Research
University of South Australia
Playford Building, Frome Road
City East Campus
Adelaide SA 5000
Australia
Country [3] 290324 0
Australia
Secondary sponsor category [4] 290325 0
Individual
Name [4] 290325 0
Ms. Maja Pajcin
Address [4] 290325 0
School of Pharmacy and Medical Sciences
Playford Building, Frome Road
University of South Australia
City East Campus
Adelaide SA 5000
Country [4] 290325 0
Australia
Secondary sponsor category [5] 290326 0
Individual
Name [5] 290326 0
Dr. Chris Della Vedova
Address [5] 290326 0
School of Pharmacy and Medical Sciences
Playford Building, Frome Road
University of South Australia
City East Campus
Adelaide SA 5000
Country [5] 290326 0
Australia
Secondary sponsor category [6] 290327 0
Individual
Name [6] 290327 0
Ms. Charlotte Gupta
Address [6] 290327 0
Centre for Sleep Research
University of South Australia
Playford Building, Frome Road
City East Campus
Adelaide SA 5000
Australia
Country [6] 290327 0
Australia
Secondary sponsor category [7] 290328 0
Individual
Name [7] 290328 0
A/Prof Leonie Heilbronn
Address [7] 290328 0
SAHMRI
North Terrace
PO Box 11060
Adelaide, SA, 5001
Country [7] 290328 0
Australia
Secondary sponsor category [8] 290329 0
Individual
Name [8] 290329 0
Prof Gary Wittert
Address [8] 290329 0
University of Adelaide
Royal Adelaide Hospital, 6th Floor, Eleanor Harrald Building
North Terrace
Adelaide, SA, 5001
Country [8] 290329 0
Australia
Secondary sponsor category [9] 290330 0
Individual
Name [9] 290330 0
Prof Dave Kennaway
Address [9] 290330 0
University of Adelaide
Adelaide SA 5005
Country [9] 290330 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293180 0
University of South Australia
Ethics committee address [1] 293180 0
City East Campus
Frome Road
Adelaide, 5000, SA
Ethics committee country [1] 293180 0
Australia
Date submitted for ethics approval [1] 293180 0
Approval date [1] 293180 0
17/10/2014
Ethics approval number [1] 293180 0
0000033621

Summary
Brief summary
The prevalence of type 2 diabetes and obesity are rising at alarming rates. Across Australia, these chronic diseases account for billions in health care costs and lost productivity. Rates of type 2 diabetes and obesity are high among shift workers, even after controlling for lifestyle and socioeconomic status. Shift workers experience poor timing of their body clocks to the daily light/dark cycle, and they show abnormal metabolic responses, including insulin resistance and glucose intolerance. Simulated shift work studies in rodents provide a link between timing of meals and metabolic processes: withholding feeding during 'night-shift' prevents the adverse metabolic effects of simulated shift work. Whether this strategy is effective in humans remains to be demonstrated. Our preliminary data from humans in several laboratory studies indicate that meal timing does play an important role in metabolic disturbance. Indeed eating at night, when the body is primed for sleep, seems to underlie an increase in metabolic disturbance that could predispose them to chronic disease. To test this, we will measure metabolic markers in healthy men studied under simulated shift work conditions, where we will keep daily energy intake constant but vary meal times. We propose that by simply altering the timing of meals we will be able to mitigate the negative metabolic consequences of shift work. These results could be readily translated to existing dietary guidelines, industry recommendations and workplace policy reducing the significant and increasing burden of metabolic disease in shift workers and the wider community.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 58798 0
Dr Siobhan Banks
Address 58798 0
Centre for Sleep Research
Playford Building, Frome Road
University of South Australia
City East Campus
Adelaide SA 5000
Country 58798 0
Australia
Phone 58798 0
+61 08 83021712
Fax 58798 0
+ 618 8302 6623
Email 58798 0
siobhan.banks@unisa.edu.au
Contact person for public queries
Name 58799 0
Dr Siobhan Banks
Address 58799 0
Centre for Sleep Research
Playford Building, Frome Road
University of South Australia
City East Campus
Adelaide SA 5000
Country 58799 0
Australia
Phone 58799 0
+61 08 83021712
Fax 58799 0
+ 618 8302 6623
Email 58799 0
siobhan.banks@unisa.edu.au
Contact person for scientific queries
Name 58800 0
Dr Siobhan Banks
Address 58800 0
Centre for Sleep Research
Playford Building, Frome Road
University of South Australia
City East Campus
Adelaide SA 5000
Country 58800 0
Australia
Phone 58800 0
+61 08 83021712
Fax 58800 0
+ 618 8302 6623
Email 58800 0
siobhan.banks@unisa.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary