Night work, circadian rhythm disorders and glucose regulation, the GLU24/7 study
| ISRCTN | ISRCTN10297427 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN10297427 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | 24/00103 |
| Sponsor | National Institute of Occupational Health |
| Funders | National Institute of Occupational Health, Norway (STAMI), Borregaard Research Fund |
- 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
| Primary study design | Observational |
|---|---|
| Study design | Two-year longitudinal observational study |
| Secondary study design | Longitudinal study |
| Study type | 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(s) |
1. The following primary outcome variables are assessed during a 6-week baseline period: |
| Key secondary outcome measure(s) |
The following secondary outcome cardiovascular disease (CVD) risk factors are assessed during a 6-week baseline period and at a 2-year follow-up: |
| Completion date | 01/06/2029 |
Eligibility
| Participant type(s) | Employee |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 70 Years |
| Sex | All |
| Target sample size at registration | 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
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request |
| 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. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
11/12/2024: Study's existence confirmed by the Regional Committees for Medical and Healthcare Research Ethics, REK south-east B.
