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Trial registered on ANZCTR


Registration number
ACTRN12621001625864
Ethics application status
Approved
Date submitted
24/10/2021
Date registered
29/11/2021
Date last updated
28/01/2024
Date data sharing statement initially provided
29/11/2021
Date results information initially provided
28/01/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
The Dose and Timing Relationship Between Caffeine and Subsequent Sleep Quantity and Quality
Scientific title
The Dose and Timing Relationship Between Caffeine and Subsequent Sleep Quantity and Quality in Healthy Adults
Secondary ID [1] 305633 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Sleep
324082 0
Condition category
Condition code
Public Health 321582 321582 0 0
Other public health
Neurological 321781 321781 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Intervention is the administration of caffeine to be taken orally in capsule form. The study is a crossover design where each participant will be randomly exposed to all seven conditions organised using a Latin Square design. Each condition will be separated by a 2 day washout period. Conditions include;
Placebo
100mg administered 12 hours prior to bedtime
100mg administered 8 hours prior to bedtime
100mg administered 4 hours prior to bedtime
400mg administered 12 hours prior to bedtime
400mg administered 8 hours prior to bedtime
400mg administered 4 hours prior to bedtime
Participants will consume three capsules on each experimental day at 12, 8 and 4 hours prior to bedtime. The caffeine capsule will be administered at the timepoint and dose relevant to the condition with the remaining two capsules containing the placebo. All three capsules will contain the placebo for the placebo condition.
Saliva samples will be collected using cotton chew swabs to monitor caffeine concentrations and compliance. These will occur on experimental days at 11, 7 and 3 hours prior to bedtime, 5 minutes prior to bedtime and 5 minutes after waking.
Intervention code [1] 322037 0
Lifestyle
Intervention code [2] 322181 0
Treatment: Other
Comparator / control treatment
Glucose will be administered as the placebo control in identical appearing capsule form
Control group
Placebo

Outcomes
Primary outcome [1] 329539 0
Total sleep time (min)
Timepoint [1] 329539 0
Recorded for duration of overnight sleep bout commencing 4 hours after last capsule consumption. This will be 12, 8 or 4 hours after caffeine consumption depending on the given condition. Measures will be recorded using partial polysomnography.
Primary outcome [2] 329540 0
Sleep efficiency (%)
Timepoint [2] 329540 0
Recorded for duration of overnight sleep bout commencing 4 hours after last capsule consumption. This will be 12, 8 or 4 hours after caffeine consumption depending on the given condition. Measures will be recorded using partial polysomnography.
Primary outcome [3] 329541 0
Sleep onset latency (min)
Timepoint [3] 329541 0
Recorded for duration of overnight sleep bout commencing 4 hours after last capsule consumption. This will be 12, 8 or 4 hours after caffeine consumption depending on the given condition. Measures will be recorded using partial polysomnography.
Secondary outcome [1] 402251 0
Salivary caffeine concentration (µg/mL)
Timepoint [1] 402251 0
Saliva collections will be completed 1 hour after each capsule administration. Capsule administration will occur at 12, 8 and 4 hours prior to bedtime therefore saliva collections will occur at 11, 7 and 3 hours prior to bedtime. Additionally, samples will be taken 5 minutes prior to bedtime and 5 minutes after waking.
Secondary outcome [2] 402252 0
Subjective level of alertness (1-10 Likert scale)
Timepoint [2] 402252 0
Assessed immediately prior to bedtime - this will be 4 hours after the last capsule is consumed. Depending on the condition, it will be 12, 8 or 4 hours post caffeine consumption.
Secondary outcome [3] 402916 0
Wake after sleep onset (min)
(Primary Outcome)
Timepoint [3] 402916 0
Recorded for duration of overnight sleep bout commencing 4 hours after last capsule consumption. This will be 12, 8 or 4 hours after caffeine consumption depending on the given condition. Measures will be recorded using partial polysomnography.
Secondary outcome [4] 402917 0
Relative percentage of time in each sleep stage (1,2,3 or REM)
(Primary Outcome)
Timepoint [4] 402917 0
Recorded for duration of overnight sleep bout commencing 4 hours after last capsule consumption. This will be 12, 8 or 4 hours after caffeine consumption depending on the given condition. Measures will be recorded using partial polysomnography.
Secondary outcome [5] 402918 0
Subjective sleep quality
(Primary Outcome)
Timepoint [5] 402918 0
Assessed using a questionnaire with a modified 1-5 Likert scale completed immediately upon waking in the morning

Eligibility
Key inclusion criteria
Apparently healthy male aged between 18 and 40 years of age
No reported medical or sleep condition
Daily habitual caffeine consumption <300mg
Minimum age
18 Years
Maximum age
40 Years
Sex
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
BMI <18kg/m2 or >26kg/m2
Consumed cigarettes, drugs or medications known to affect sleep in the 3 months prior to study admission
Undertaken shift work or transmeridian travel in the 3 months prior to study admission

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled 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
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s

Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

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)
QLD

Funding & Sponsors
Funding source category [1] 309993 0
University
Name [1] 309993 0
Australian Catholic University
Country [1] 309993 0
Australia
Primary sponsor type
University
Name
Australian Catholic University
Address
1100 Nudgee Road, Banyo QLD 4014
Country
Australia
Secondary sponsor category [1] 311042 0
None
Name [1] 311042 0
Address [1] 311042 0
Country [1] 311042 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 309702 0
Australian Catholic University Human Research Ethics Committee
Ethics committee address [1] 309702 0
Australian Catholic University
North Sydney Campus
PO Box 968
NORTH SYDNEY, NSW 2059
Ethics committee country [1] 309702 0
Australia
Date submitted for ethics approval [1] 309702 0
25/10/2021
Approval date [1] 309702 0
01/02/2022
Ethics approval number [1] 309702 0

Summary
Brief summary
This research project is investigating if the amount of caffeine and the time that it is consumed during the day changes the quantity and quality of night-time sleep. The project will involve a low (100mg) and high (400mg) dose of caffeine administered in the morning, afternoon and evening to find out if the effect on sleep changes. Given caffeine is a stimulant, it is expected that sleep will be influenced when more caffeine is consumed closer to bedtime. By investigating different dose and timing combinations, we are aiming to determine if there is a cut-off time for consuming caffeine to avoid poor sleep. This is important as poor sleep is associated with an increased risk of illness, accidents and injuries.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 115094 0
Prof Shona Halson
Address 115094 0
Australian Catholic University
1100 Nudgee Road, Banyo QLD 4014
Country 115094 0
Australia
Phone 115094 0
+61 422 224 491
Fax 115094 0
Email 115094 0
Contact person for public queries
Name 115095 0
Miss Carissa Gardiner
Address 115095 0
Australian Catholic University
1100 Nudgee Road, Banyo QLD 4014
Country 115095 0
Australia
Phone 115095 0
+61 439 833 967
Fax 115095 0
Email 115095 0
Contact person for scientific queries
Name 115096 0
Miss Carissa Gardiner
Address 115096 0
Australian Catholic University
1100 Nudgee Road, Banyo QLD 4014
Country 115096 0
Australia
Phone 115096 0
+61 439 833 967
Fax 115096 0
Email 115096 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
13744Ethical approval  [email protected]



Results publications and other study-related documents

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