Plain English Summary
Background and study aims
Social jetlag is a chronic disruption of sleep timing that is characterized by different sleep timing
during workdays and free days. It has been associated with higher risk of obesity and diabetes.
In this intervention study we will investigate whether a combination of bright light therapy in
the morning, bright light reduction in the evening, and sleep timing instructions for 3 weeks
compared to regular sleep habits can reduce social jetlag and if this results in changes in glucose
levels, metabolism, sleep, mood, and quality of life in people with (pre)diabetes after 3 and 12 weeks follow-up.
Who can participate?
60 people with pre-diabetes and diabetes with >1 hour social jetlag from the Hoorn Study and
Diabetes Care System cohorts can participate.
What does the study involve?
The study involves measurements at the study center (height and weight, fat percentage, ECG
and SUDO scan, questionnaires, blood pressure, blood draw), collecting saliva samples at home
and performing at-home sleep measurements using a headband.
The intervention consists of wearing light dimming goggles at night, using a bright light lamp in
the morning and adhering to sleep instructions for 3 weeks. To assess adherence to the study
protocol, participants in the intervention group will be asked to wear an accelerometer and light sensor and fill in a sleep diary for one week during the intervention. After that, all measurements from
the baseline are repeated after 3 and 12 weeks.
What are the possible benefits and risks of participating?
Study participants need to invest time in the study and they need to adhere to the
minimally invasive intervention protocol daily. Furthermore, a total amount of 26ml of blood will
be drawn. Participants have no direct benefit from this study. By participating in the study, new
data on the health of the participant can be detected. If important health information is
discovered, a participants general practitioner will be informed. We expect that people who
follow the intervention protocol will be able to reduce their social jetlag and consistently improve their glycemic control.
Where is the study run from?
Amsterdam UMC at the study location in Hoorn (Netherlands)
When is the study starting and how long is it expected to run for?
July 2023 to October 2024
Who is funding the study?
Dutch Diabetes Foundation Diabetes Fonds Fellowship, Grant/Award Number: 2019.82.002
Who is the main contact?
Dr Femke Rutters, f.rutters@amsterdamumc.nl
Study website
Contact information
Type
Public, Scientific, Principal Investigator
Contact name
Dr Femke Rutters
ORCID ID
http://orcid.org/0000-0002-1008-678X
Contact details
Meibergdreef 9
Amsterdam
1105AZ
Netherlands
+31 20 44 45860
f.rutters@amsterdamumc.nl
Additional identifiers
EudraCT/CTIS number
Nil known
IRAS number
ClinicalTrials.gov number
Nil known
Protocol/serial number
Grant/Award Number: 2019.82.002
Study information
Scientific title
A randomized controlled trial to assess change in glucose metabolism by changing sleep timing in people with (pre)diabetes
Acronym
Study hypothesis
A combination of bright light therapy in the morning, bright light reduction in the evening and sleep advance instructions for 3 weeks reduces social jetlag and results in changes in glycemic and metabolic control, sleep, mood and quality of life in people with (pre)diabetes after 3 and 12 weeks follow-up.
Ethics approval(s)
Approved 14/03/2024, Amsterdam UMC Medical Research Ethics Committe (Van der Boechorststraat 7, Amsterdam, 1081BT, Netherlands; +31 (0)20-4445585; metc@amsterdamumc.nl), ref: 2023.0964
Study design
Single center randomized controlled trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Study setting(s)
University/medical school/dental school
Study type
Prevention
Patient information sheet
See outputs table
Condition
Prevention of diabetes for people with social jetlag
Intervention
The intervention consists of Bright light therapy (5000 lux) emitted by Vitamine-L (Lumie, UK) or dim light (10 lux) for 30 minutes each morning, following sleep advance instructions, and wearing bright light dimming goggles every evening for a period of 3 weeks. The control group adheres to their regular sleep habits and conditions.
Randomization will be performed by a statistician from the data management department, who is not involved in the study by using a randomization list. Blocked randomization will be used to ensure good balance of participant characteristics in each group. Randomization will be stratified on sex, two strata of age and two strata of social jetlag to prevent misbalance. Allocation will be determined by using a computerized random number generation process. Due to the nature of the intervention, blinding is not possible. However, since the primary outcomes are glycemic parameters, we do not expect large placebo effects on these outcomes.
Intervention type
Behavioural
Primary outcome measure
Glycemic control measured as HbA1c levels comparing the intervention and control group in an
intention to treat analysis at baseline after 12 weeks.
Secondary outcome measures
All outcomes will be measured over the duration of 3 weeks and 12 weeks:
1. Other glycemic measures: fasting blood glucose and insulin levels, medication use and frequency of hypoglycemic sensation;
2. Metabolic outcomes, including BMI, waist, blood pressure, fat percentage, (para)sympathetic nervous system activity from ECGs and electrochemical skin conductance tests,
3. Sleep measured as sleep times, sleep quality and sleep phases using a sleep measuring Headband (only after 3 weeks);
4. Mood including depression, fatigue and anxiety measured using questionnaires
5. Quality of life measured using the EQ5D questionnaire.
6. Additionally, to assess other factors that might play a role (possible mediators), we will assess the Dim Light Melatonin Onset (DLMO) in saliva samples (in a subgroup), feeling of satiety and satiation is assessed using a 10-cm VAS scale and physical activity using an accelerometer.
Overall study start date
09/07/2023
Overall study end date
01/10/2024
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Social jetlag (>1h) (calculated as difference between midpoint of sleep during week days and free weekend days)
2. (Pre) diabetes: HbA1c >39 mmol/mol (5.7%), fasting plasma glucose >5.6 mmol/l, or 2-hour OGTT >7.8mmol/l (according to the American Diabetes Association) including the use of any glucose-lowering medication
3. Informed consent to be contacted for future research
4. Willing to comply with the study procedures
Participant type(s)
Healthy volunteer
Age group
Adult
Lower age limit
18 Years
Upper age limit
79 Years
Sex
Both
Target number of participants
60
Participant exclusion criteria
1. Excessive alcohol use (>21 alcoholic consumptions per week);
2. Having crossed more than 1 time zone in the month prior to participation;
3. Working shifts more than once per month;
4. Unable to provide written informed consent;
5. Visually impaired;
Recruitment start date
01/04/2024
Recruitment end date
09/07/2024
Locations
Countries of recruitment
Netherlands
Study participating centre
Amsterdam UMC
Maelsonstraat 7
Hoorn
1624NP
Netherlands
Sponsor information
Organisation
Amsterdam UMC Location VUmc
Sponsor details
Meibergdreef 9
Amsterdam
1105AZ
Netherlands
+31 20 44 45860
f.rutters@amsterdamumc.nl
Sponsor type
Hospital/treatment centre
Website
ROR
Funders
Funder type
Charity
Funder name
Diabetes Fonds
Alternative name(s)
Dutch Diabetes Research Foundation
Funding Body Type
private sector organisation
Funding Body Subtype
Trusts, charities, foundations (both public and private)
Location
Netherlands
Results and Publications
Publication and dissemination plan
Planned publication in a high-impact peer-reviewed journal
Intention to publish date
01/06/2026
Individual participant data (IPD) sharing plan
The datasets generated during and/or analysed during the current study will be available upon request from the Hoorn Steering Committee (hoornstudy@amsterdamumc.nl).
IPD sharing plan summary
Available on request
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | version 2 | 02/02/2024 | 22/03/2024 | No | Yes |
| Protocol file | version 3 | 21/02/2024 | 22/03/2024 | No | No |