Clinical trial NCT03829982: The Effects of Light on Glucose Metabolism
Official title: The Effects of Light on Glucose Metabolism
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Diabetes Mellitus, Type 2
Glucose Intolerance
Prediabetic State
Keywords: Circadian Rhythm
Lead sponsor: Maastricht University
Sponsor class: OTHER
Collaborators: name: Maastricht University Medical Center
First posted: 2019-02-04
Enrollment: 14
Sex: ALL
Minimum age (years): 40
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Crossover Assignment
Primary purpose: BASIC_SCIENCE

Brief summary: This study evaluates the effect of bright light on postprandial blood glucose metabolism in obese subjects with impaired fasting glucose and/or impaired glucose tolerance.

Detailed description: Light has a major influence on the biological clock and several studies suggest that bright light during the day and dim light in the evening are beneficial for the circadian timing system. Nowadays, large parts of the population spend 90% of their time indoors and are thereby exposed to artificial lighting instead of daylight. The artificial light levels are relatively low during the day and continue relatively late in the evening. The lack of a clear natural light-dark cycle could results in delayed timing of the biological clock relative to the behaviour. Optimizing the lighting conditions under controlled laboratory settings might lead to better alignment of the biological clock, which in turn could improve metabolic parameters such as glucose control.

Eligibility criteria: Inclusion Criteria:

* Caucasian
* BMI 25-35 kg/m2
* Stable weight (+/- 3 kg in the last 3 months)
* One of the four criteria for prediabetes:

  * Impaired fasting glucose (6.1 mM to 6.9 mM)
  * Blood glucose values 7.8 - 11.1 mM 2h after glucose drink consumption during the oral glucose tolerance test (OGTT) in screening
  * Insulin Resistance: glucose clearance rate ≤ 360 ml/kg/min, as determined using the oral glucose insulin sensitivity (OGIS120) index
  * HbA1c of 5.7 - 6.4%.

Exclusion Criteria:

* Fasting plasma glucose ≥7.0 mM
* Blood donation one month prior to study and three months after finishing study.
* Participants with extreme chronotypes (going to bed extremely late/early).

Primary outcomes:
measure: Postprandial glucose (mg/dL)
timeFrame: Study Day 1-3
Secondary outcomes:
measure: Glucose levels (mmol/L) in the postprandial state
timeFrame: Study Day 2-3
measure: Free fatty acid levels (µmol/L) in the postprandial state
timeFrame: Study Day 2-3
measure: Triglycerides levels (mmol/L) in the postprandial state
timeFrame: Study Day 2-3
measure: Insulin levels (µU/mL) in the postprandial state
timeFrame: Study Day 2-3
measure: Continuous interstitial glucose (mg/dL)
timeFrame: Study Day 1-3
measure: Energy expenditure
timeFrame: Study Day 1-3
measure: Core body temperature (CBT) and skin temperature
timeFrame: Study Day 1-3
Other outcomes:
Locations:
city: Maastricht
country: Netherlands
facility: Maastricht University
state: Limburg
Study officials:
affiliation: Maastricht University
name: Wouter van Marken Lichtenbelt, Prof. Dr.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Harmsen JF, Wefers J, Doligkeit D, Schlangen L, Dautzenberg B, Rense P, van Moorsel D, Hoeks J, Moonen-Kornips E, Gordijn MCM, van Marken Lichtenbelt WD, Schrauwen P. The influence of bright and dim light on substrate metabolism, energy expenditure and thermoregulation in insulin-resistant individuals depends on time of day. Diabetologia. 2022 Apr;65(4):721-732. doi: 10.1007/s00125-021-05643-9. Epub 2022 Feb 2.