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Trial registered on ANZCTR


Registration number
ACTRN12617000346370
Ethics application status
Approved
Date submitted
17/02/2017
Date registered
6/03/2017
Date last updated
12/02/2021
Date data sharing statement initially provided
12/02/2021
Date results information initially provided
12/02/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Developmental differences in circadian rhythm establishment in preterm and term infants
Scientific title
Developmental differences in circadian rhythm establishment in preterm and term infants
Secondary ID [1] 291189 0
Nil
Universal Trial Number (UTN)
Trial acronym
CIRCADIEM Baseline
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Circadian rhythm development in preterm and term infants 302080 0
Condition category
Condition code
Reproductive Health and Childbirth 301710 301710 0 0
Complications of newborn
Metabolic and Endocrine 301766 301766 0 0
Normal metabolism and endocrine development and function

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
This study compromises the collection of salival and buccal swabs. An initial set of baseline swabs will be collected with the first 72 hours postpartum, and are taken every 4 hours for the selected 24-hour period (i.e day 2 of life at 04h00/08h00/12h00/16h00/20h00/00h00). Thereafter, buccal and saliva swabs will be taken in the same manner (i.e. every 4 hours for 24 hours) on day 14 and day 28 postnatal age. We will also take the same set of saliva and buccal swabs (every 4 hours for 24 hours) at week 36 postmenstrual age, and 1, 2 and 3 months corrected postnatal age.
Infant weight, length and head circumference will be measured on the above sampling days and an actimeter will be fitted to the infant to measure physical activity for the duration of each sampling day (i.e. 24 hours).
Intervention code [1] 297190 0
Not applicable
Comparator / control treatment
All measurements will be taken in preterm and term infants. The study samples will be take in 4 different gestational age group: Extremely preterm infants (<28 weeks postmenstrual age), Very preterm infants (28- <32 weeks postmenstrual age), Moderately preterm infants (32-<36 weeks postmenstrual age), and Term Infants (39-41 weeks postmenstrual age). Term infants (39-41 weeks postmenstrual age) represent the control/comparator population and will define the "normal" circadian rhythm development pattern against which the preterm infant developmental patterns will be assessed. There is no intervention in this observational study.
Control group
Active

Outcomes
Primary outcome [1] 301110 0
Time to establishment of circadian rhythm in cortisol and melatonin secretion.
Saliva samples are taken every 4 hours for a 24 hour period. From these 6 consecutive samples we are able to determine how the rhythm of cortisol and melatonin fluctuates across the 24 hour day and hence determine whether a typical circadian rhythm is depicted in these patterns. Cortisol and melatonin concentrations are determined from the samples by enzyme immunoassay (EIA).
The circadian rhythm of the hormones are determined by means of a cosinor analysis.
Timepoint [1] 301110 0
The time to establish a circadian rhythm will be established as the time taken until cosinor analysis shows a significant rhythm is present, for cortisol and melatonin. (Saliva sampling days, defined as 6 samples across a 24 hour period are initially determined within the first 72 hours of life. Identical sample days are then repeated at day 14, and 28 days. In preterm infants we will take another set of samples at 36 weeks postmenstrual age. All infants will have samples obtained at 1, 2 and 3 months corrected postnatal age.
Secondary outcome [1] 331755 0
This is a composite secondary outcome at 36 w postmenstrual age for preterm infants of time to development of circadian rhythm of heart rate/pulse/respiration rate during hospitalisation. These physiological measurements are all determined and assessed from downloads of NICU monitors at the cot bedside. Analysis of amplitude, mesor and phase of circadian rhythms of heart rate/pulse/respiration rate in preterm and term infants are performed using a cosinor analysis. If a circadian rhythm has developed at any given timepoint, the cosinor analysis shows a significant outcome.
Timepoint [1] 331755 0
The time to establish a circadian rhythm in cardiorespiratory circadian rhythms will be established as the time taken until cosinor analysis of measurements obtained at any nominated measurement point shows a significant rhythm is present in cardiorespiratory circadian rhythms. (Monitor downloads will be obtained at the end of each of the determined sampling days, i.e withing the first 72 hours of life, then at day 14, day 28 and at 36 weeks postmenstrual age (for preterm infants born less than 36 weeks only) .
Secondary outcome [2] 331897 0
Time to development of circadian rhythm in physical activity

Outcome is assessed using an actimeter worn on the left lower limb. Actimeters will be fitted for the duration of the sampling days (24 hours). Cross-sectional analysis of amplitude, mesor and phase of circadian rhythms physical activity in preterm and term infants are performed using a cosinor analysis.
Timepoint [2] 331897 0
The time to establish a circadian rhythm in physical activity will be established as the time taken until cosinor analysis of measurements obtained at any nominated measurement point shows a significant rhythm is present in physical activity. Actimeters will be fitted for the first sampling day that occurs withing the first 72 hours of life, then for 24 hourson days 14, day 28 and at 36 weeks post-menstrual ages (for preterm infants born less than 36 weeks only) and finally at 1, 2 and 3 months corrected postnatal age ( common sample time points with term infants).
Secondary outcome [3] 331899 0
Parental attitudes to circadian intervention will also be assess by means of a customised parent survey designed for this study.
Parental survey data will be collated and put into a simple coding system which will be used to rank the data. Answers that already contain a numerical scale, will likely be ranked on a similar scale. Answers to open ended questions and review responses will be categorised into a sufficiently small set of broad categories which will then be ranked accordingly. These data can be analysed with the use of a Chi-squared test.
Timepoint [3] 331899 0
These surveys will be administered to the parents at the end of the study once the final samples have been taken from their infants. Surveys will be sent out via email and submitted into a secure database called REDCap.
Secondary outcome [4] 331900 0
Time to establish a regular and rhythmic expression of core circadian clock genes.

Buccal samples allow us to determine clock gene expression of the clock genes Bmal1, Per 2 and Reverb-alpha. The expression of these specific clock genes at particular times of day determines circadian variation that occurs in many other other tissues, physiological processes and hormonal fluctuations. It is therefore important that we obtain this information in conjunction with the hormonal data to determine whether the expression of these clock genes matches up with the rhythms depicted in the hormones described in Primary outcome 1. Clock gene expression is determined by examination of mRNA levels of each clock gene by means of PCR.

Timepoint [4] 331900 0
The time to establish a circadian rhythm will be established as the time taken until cosinor analysis shows a significant rhythm is present in the core clock gene expression. Buccal samples occur at the same time as saliva samples, defined as 6 samples across a 24 hour period are initially determined within the first 72 hours of life. Identical sample days are then repeated on day 14, and day 28 . In preterm infants we will take another set of samples at 36 weeks postmenstrual age. All infants have samples obtained at 1, 2 and 3 months corrected postnatal age (common sample timepoints with term infants).

Eligibility
Key inclusion criteria
1. <28 weeks postmenstrual age
2. 28-<32 weeks postmenstrual age
3. 32-<36 weeks postmenstrual age
4. 39-41 weeks postmenstrual age
Minimum age
No limit
Maximum age
3 Days
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Any abnormality of the central nervous system
Any congenital abnormality requiring surgery in the first 4 months
Any jaundice with SBR>400 mmol/L or requiring exchange transfusion
Any hypoxic ischaemic encephalopathy (any grade)
Intraventricular haemorrhage > Gr 2
10 minute apgar score of less than 5.
Term infants with illness necessitating overnight admission to NICU
Infants with mothers that took CNS active medication whilst pregnant
Infants with mothers that partook in any substance abuse whilst pregnant
Infants with mothers that have hypothyroidism or hyperthyroidism or any other condition that affects the HPA axis.

Study design
Purpose
Natural history
Duration
Longitudinal
Selection
Defined population
Timing
Prospective
Statistical methods / analysis
A group size of 10 participants per gestational age group will facilitate detection of a minimum mean difference of 4 weeks in the time taken to establish a circadian rhythm in cortisol and melatonin secretion based on an expected standard deviation of residuals of 2.06 (McMillen et al, Pediatr Res 1991; 29: 381-384) with a power 0.824 and alpha = 0.01.

Circadian rhythms in each of the physiological measures of interest (e.g., activity, temperature, heart rate, respiration rate, salivary hormones, clock gene expression) will be analysed using cosinor analysis (computing macro on Microsoft Office Excel 2013) to establish the outcome variables of amplitude, mesor, phase and period for each gestational age group at each timepoint. Data will be analysed subsequently in SPSS v23 (IBM Business Analytics Software, NSW, Australia).

Cross sectional analyses will apply a general linear model with adjustment for covariates (ANCOVA) at the common maturational time points of 36 w and 44w postmenstrual age. Cross sectional analyses will use the gestational age group as the between subjects factor and potential covariates such as sex, duration of mechanical ventilation, postnatal sepsis episodes, and postnatal steroid treatment to ascertain differences between gestational age groups at each maturational time point, to define absolute differences between groups, and independent predictors.

To analyse differences in the time to the onset of a circadian rhythms, the rate of development of circadian rhythm will be analysed at the individual patient level for each outcome variable and compared between groups using ANCOVA using potential explanatory factors as described above.

Determinants of time to onset will be analysed using multiple linear regression analysis. Where multicollinearity exists between potential explanatory variables, factor reduction will be achieved using principal components 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)
WA
Recruitment hospital [1] 7494 0
King Edward Memorial Hospital - Subiaco
Recruitment hospital [2] 7495 0
Fiona Stanley Hospital - Murdoch
Recruitment postcode(s) [1] 15319 0
6008 - Subiaco
Recruitment postcode(s) [2] 15320 0
6150 - Murdoch

Funding & Sponsors
Funding source category [1] 295631 0
Other
Name [1] 295631 0
NHMRC Preterm Infant Centre of Research Excellence
Country [1] 295631 0
Australia
Funding source category [2] 295635 0
Government body
Name [2] 295635 0
Telethon Perth Children's Hospital Medical Research Fund
Country [2] 295635 0
Australia
Primary sponsor type
University
Name
University of Western Australia
Address
School of Human Sciences
35 Stirling Hwy,
Crawley WA 6009
Western Australia
Country
Australia
Secondary sponsor category [1] 294472 0
Hospital
Name [1] 294472 0
King Edward Memorial Hospital
Address [1] 294472 0
374 Bagot Road
Subiaco
WA, 6009
Country [1] 294472 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296949 0
Women and Newborn Health Services HREC
Ethics committee address [1] 296949 0
King Edward Memorial Hospital,
374 Bagot Road,
O Block
Subiaco, WA 6008
Ethics committee country [1] 296949 0
Australia
Date submitted for ethics approval [1] 296949 0
22/08/2016
Approval date [1] 296949 0
01/11/2016
Ethics approval number [1] 296949 0
2016106EW
Ethics committee name [2] 296952 0
University of Western Australia
Ethics committee address [2] 296952 0
35 Stirling Hwy,
Crawley WA 6009
Ethics committee country [2] 296952 0
Australia
Date submitted for ethics approval [2] 296952 0
24/01/2017
Approval date [2] 296952 0
31/01/2017
Ethics approval number [2] 296952 0
RA/4/1/8927

Summary
Brief summary
A circadian rhythm is any endogenous biological process exhibiting an entrainable daily oscillation. Circadian rhythms are essential for normal physiological and behavioural functioning and alignment with the 24 h light/dark cycle. Circadian rhythms are coordinated by a set of rhythmically expressed clock genes. A ‘master clock’ in the hypothalamic suprachiasmatic nucleus (SCN) synchronises peripheral cellular clocks and hormonal rhythmicity (e.g., plasma melatonin and cortisol concentrations). Light is the dominant environmental cue setting the rhythm of the SCN master clock.
The developing fetus is not exposed to light. The development of the fetal circadian system is driven by maternal variation in circadian hormones transmitted to the fetus via the placenta. The fetus cannot synthesise its own hormones until near term. Premature delivery deprives the fetus of these materno-placental circadian cues. Hospitalisation of preterm infants in the neonatal intensive care unit (NICU) further disrupts circadian input and rhythm development due to constant lighting and noise, and invasive procedures/therapies.
This prospective study is observational and investigates the circadian rhythm development across infants of different gestational ages; gestation specific patterns will be identified from physiological, hormonal and molecular outcome variables. This study will inform a second prospective study; a randomised-controlled trial of two interventions to normalise circadian rhythm development in preterm infants: modification of environmental light/dark information; and environmental modification with additional time-specific supplementation of endogenous circadian hormones (melatonin and cortisol). The clinical trial will identify if a circadian intervention improves short-term clinical outcomes.
Trial website
None
Trial related presentations / publications
None
Public notes

Contacts
Principal investigator
Name 72518 0
A/Prof Jane Pillow
Address 72518 0
University of Western Australia
School of Human Sciences, M309
35 Stirling Hwy,
Crawley WA 6009
Country 72518 0
Australia
Phone 72518 0
+61 8 6488 3318
Fax 72518 0
Email 72518 0
Contact person for public queries
Name 72519 0
Dr Peter Mark
Address 72519 0
University of Western Australia
School of Human Sciences, M309
35 Stirling Hwy,
Crawley WA 6009
Country 72519 0
Australia
Phone 72519 0
+61 8 6488 2609
Fax 72519 0
Email 72519 0
Contact person for scientific queries
Name 72520 0
Miss Natasha Sorensen
Address 72520 0
King Edward Memorial Hospital
Neonatal Clinical Care Unit
374 Bagot Road
Subiaco, Perth
Western Australia
Australia 6008
Country 72520 0
Australia
Phone 72520 0
+61447583980
Fax 72520 0
Email 72520 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Data dictionaries – yes (REDCap download)
Individual participant data – IPD underlying published materials only stored in data repository will be made available on reasonable request
When will data be available (start and end dates)?
30/09/2020-30/09/2021
Available to whom?
Fellow researchers, hospital staff, and community members on special request
Available for what types of analyses?
Researchers will be able to use the data for systematic meta-analyses.
How or where can data be obtained?
Upon request through Professor Jane Pillow at the University of Western Australia. Please email [email protected]


What supporting documents are/will be available?

Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.