Developing an effective method of determining circadian phase in humans for clinical applications

Completed

• Conditions: individuele variatie in 24-uurs ritmiek; biological rhythm; circadian clock

• Registration Number: NL-OMON42265
• Lead Sponsor: Rijksuniversiteit Groningen

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Last Update Posted: 23 April 2024

Recruitment & Eligibility

• Status: Completed
• Sex: Not specified
• Target Recruitment: 72

Inclusion Criteria

healthy men and women, aged 20-30 or 50-60
early/late/normal chronotype

Exclusion Criteria

Bad sleepers (PSQI >10)
Depressive tendencies (BDI >8) (HADS >8)
Anxiety problems (HADS >8)
Chronotype of relatively late (20-30 year olds MSF 5.63-6.29-60 year olds MSF 4.5-5.08) or relatively early (20-30 year olds MSF 4.29-5.044, 50-60 year olds MSF 3.27-4.0)
Chronic (psychiatric or somatic) disease
Smokers
Recreational drug use (e.g. cannabis, ectasy, GHB etc.)
Past head injury or epileptic fits
Medically diagnosed sleep disorders
Eye complaints or eye surgery in the past (not including contact lenses or glasses)
Use of chronic (photosensitizing) medication in 3 months prior to the start of the study
Regular use of sleep medication or stimulating drugs
Colour blindness
More than 3 glasses of alcohol per day
More than 8 caffeinated drinks per day
Shiftwork in 3 months prior to the start of the study
Travelled across more than 1 timezone in the month prior to the start of the study
People with a BMI lower than 18 and higher than 27, or weighing below 36kg.
Actual or suspected gastrointestinal obstructive disease
Having a disorder or impairment of the gag reflex
Previous gastrointestinal surgery
Felinization of the oesophagus
Hypo-motility disorders of the gastrointestinal tract
Cardio pacemaker or any other implanted electro-medical device
People who work with or plan to come in contact with Magnetic devices during the study (hospital or scientific grade only)

Study & Design

• Study Type: Observational non invasive
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>The primary study parameters are the model parameter-estimates of the daily<br /><br>profile of skin temperature, light exposure, core body temperature, activity,<br /><br>heart rate, sleep parameters (EEG and self-reported) and salivary melatonin<br /><br>profile for each participant. The outcome measures will be the different model<br /><br>parameter estimates required for late/early chronotypes, both sexes and the two<br /><br>age groups to best estimate the phase determined by the salivary melatonin<br /><br>sampling.</p><br>

Secondary Outcome Measures

Name	Time	Method
<p>Differences between working days an free days will also be analysed, but this<br /><br>is not determinant for the size of the study population.</p><br>