Night work, circadian rhythm disorders and glucose regulation, the GLU24/7 study
| ISRCTN | ISRCTN10297427 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN10297427 |
| Secondary identifying numbers | 24/00103 |
- Submission date
- 11/12/2024
- Registration date
- 21/03/2025
- Last edited
- 21/03/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Ongoing
- Condition category
- Circulatory System
Plain English summary of protocol
Background and study aims
The literature suggests an association between night shift work and disturbances of the circadian rhythm causing hormonal changes and metabolic disturbances and increased risk for cardiovascular disease (CVD). No studies have yet explored whether sleep and circadian disturbances associated with consecutive night shifts have an acute impact on the ability to maintain stable blood glucose levels. Furthermore, the long-term, prospective influence of such disturbances on risk factors for developing diabetes and CVD remains unexamined, highlighting a critical gap in our understanding of the metabolic and cardiovascular implications of shift work. This study will use a comprehensive set of methods prospectively to identify the effects of shift work with night shifts on metabolic and cardiovascular health throughout 6-weeks (phase I) and perform baseline CVD-risk factor registration (phase II). The latter will be performed again after two years (phase III). The study will provide new knowledge on the association between exposure to shift work including work at night and possible metabolic disturbances and CVD risk.
Who can participate?
Workers at an industrial Pharma plant in Norway
What does the study involve?
Participants will be expected to wear an Oura Gen 3 health tracker ring, and a Continuous Glucose Monitoring (CGM) sensor, keep a food diary, and provide multiple blood samples. There will also be a clinical examination of blood pressure, resting heart rate (RHR), arterial stiffness using carotid to femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), and cardiorespiratory fitness utilizing a cycle ergometer measuring maximal oxygen uptake (V̇O2max)
What are the possible benefits and risks of participating?
Participants will get a thorough medical examination two years apart to check their health development.
There are no significant risks of participating.
Where is the study run from?
STAMI (National Institute of Occupational Health), Norway
When is the study starting and how long is it expected to run for?
September 2024 to June 2029
Who is funding the study?
1. STAMI
2. Borregaard Research Fund
Who is the main contact?
Dr Fred Haugen, fred.haugen@stami.no
Contact information
Public, Scientific, Principal Investigator
STAMI, Gydas vei 8
Oslo
0363
Norway
 ORCID ID |
0000-0001-7201-7344 |
|---|---|
| Phone | +4723195100 |
| fred.haugen@stami.no |
Study information
| Study design | Two-year longitudinal observational study |
|---|---|
| Primary study design | Observational |
| Secondary study design | Longitudinal study |
| Study setting(s) | Workplace |
| Study type | Prevention |
| Participant information sheet | Not available in web format, please use the contact details to request a participant information sheet |
| Scientific title | Glucometabolic health and cardiovascular risk factors in night shift workers - a protocol for a 2-year longitudinal study in an industrial setting |
| Study acronym | GLU24/7 |
| Study objectives | Night shift work is associated with acute blood glucose variability with implications for long-term cardio-metabolic health |
| Ethics approval(s) |
Approved 04/09/2024, REK sor-ost B (Postboks 1130, Blindern, Oslo, 0318, Norway; +4722855240; rek-sorost@medisin.uio.no), ref: 745702 |
| Health condition(s) or problem(s) studied | Development of cardio-metabolic symptoms in night shift workers |
| Intervention | During a 6-week baseline period, sleep and physical activity will be monitored using actimetry (Gen 3 health tracker ring, OURA). Continuous glucose monitoring (Freestyle Libre Pro iQ-system, Abbott) and food diary will be performed for two weeks among all participants. Circadian rhythm markers (monocyte mRNA expression) will be analyzed at two timepoints. At the end of the 6 weeks, CVD-risk factors registration includes cardiometabolic blood parameters, markers of inflammation, and lipid profile. In this part of the study, blood pressure will also be measured, resting heart rate (RHR), arterial stiffness using carotid to femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), and cardiorespiratory fitness utilizing a cycle ergometer measuring maximal oxygen uptake (V̇O2max). At a 2-year follow-up, the baseline CVD-risk factor registration will be repeated. |
| Intervention type | Other |
| Primary outcome measure | 1. The following primary outcome variables are assessed during a 6-week baseline period: 1.1. Sleep and physical activity are measured using actimetry with the Gen 3 health tracker ring (OURA) 1.2. Glucose variability is measured using continuous glucose monitoring (CGM) with the Freestyle Libre Pro iQ-system (Abbott) and recorded in a food diary for two weeks. 2. 2. Circadian rhythm is measured by analyzing monocyte mRNA expression using Gene Expression Profiling (Nanostring) at two timepoints in the shift schedule; in the morning after consecutive night shifts or before a day shift in the baseline period. |
| Secondary outcome measures | The following secondary outcome cardiovascular disease (CVD) risk factors are assessed during a 6-week baseline period and at a 2-year follow-up: 1. Cardiometabolic blood parameters measured using Luminex or ELISA 2. Markers of inflammation measured using Luminex or ELISA 3. Lipid profile measured using enzymatic assays on a Cobas 8000 4. Blood pressure and resting heart rate (RHR) measured after a 5-minute seated rest from the subject’s left arm utilizing a BpTRU device 5. Arterial stiffness measured carotid to femoral pulse wave velocity (cfPWV) using SphygmoCor XCEL instrument 6. Carotid intima-media thickness (cIMT) measured using ultrasound scanning of both common carotid arteries proximal to the carotid bifurcation 7. Cardiorespiratory fitness measured using a cycle ergometer to measure maximal oxygen uptake (V̇O2max) |
| Overall study start date | 04/09/2024 |
| Completion date | 01/06/2029 |
Eligibility
| Participant type(s) | Employee |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 70 Years |
| Sex | Both |
| Target number of participants | 60 |
| Key inclusion criteria | Rotating night shift work or day shift work only |
| Key exclusion criteria | Issues with blood pressure |
| Date of first enrolment | 03/10/2024 |
| Date of final enrolment | 28/02/2025 |
Locations
Countries of recruitment
- Norway
Study participating centre
Oslo
0363
Norway
Sponsor information
Research organisation
STAMI, Gydas vei 8
Oslo
0363
Norway
| Phone | +4723195100 |
|---|---|
| postmottak@stami.no | |
| Website | https://www.stami.no |
"ROR" |
https://ror.org/04g3t6s80 |
Funders
Funder type
Research organisation
No information available
No information available
Results and Publications
| Intention to publish date | 31/12/2027 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Available on request |
| Publication and dissemination plan | Several articles are planned in peer reviewed journals |
| IPD sharing plan | The datasets generated during and/or analysed during the current study are/will be available upon request from Dr Fred Haugen, fred.haugen@stami.no. The health information will be given to participants if they want it. Data will be made available for participants upon request. |
Editorial Notes
11/12/2024: Study's existence confirmed by the Regional Committees for Medical and Healthcare Research Ethics, REK south-east B.
