Effects of Caffeine on Sleep-wake Regulation in Teenagers
- Conditions
- AdolescenceCaffeine
- Interventions
- Other: PlaceboOther: Caffeine
- Registration Number
- NCT04321785
- Lead Sponsor
- Carolin Reichert
- Brief Summary
The aim is to quantify the effects of one dose of caffeine (compared to placebo) on sleep and wakefulness in adolescents.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 18
- Self-reported habitual caffeine consumption: min. 80 mg per month until max 300 mg per week as estimated from mean caffeine content per serving of caffeine containing beverages and food
- Body-Mass-Index: 16.2-25.4
- Informed Consent as documented by signature of participant
- Informed Consent as documented by signature of legal representative
- Previous enrollment into the current study
- Investigators' family members, employees or other dependent persons
- Left-handedness
- No normal current health as based on questionnaires, screenings of urine, and examination by the physician in charge
- Drug use: Volunteers must be drug-free for the entire duration of the study, with no history of drug or alcohol dependency.
- Participation in other clinical trials <3 months prior to study begin
- Shift work <3 months prior to study begin
- Transmeridian travel (>2 time zones) <1 month prior to study begin
- Extreme Chronotype (Munich Chronotype Questionnaire [17], MCTQ <2 or >7)
- Short or long sleep duration: subjective sleep duration during schooldays not between 6-10 h (based on MCTQ)
- Inability to follow procedures
- Insufficient knowledge of project language (German)
- Circumstances endangering MRI safety
- Non-compliance with sleep/wake times during ambulatory part (deviation of more than ±1.5 hour from scheduled times)
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Placebo Placebo - Caffeine Caffeine -
- Primary Outcome Measures
Name Time Method Change of brain blood-oxygen-level-dependent activity after caffeine intake (vs. placebo) Start of measurements around 45 minutes once after placebo, once after caffeine Using magnetic resonance imaging (MRI), we measure blood-oxygen-level-dependent activity in the brain during a working memory task. How higher blood-oxygen-level-dependent activity can be interpreted depends on behavioral performance.
Change of sleep after caffeine intake (vs. placebo) Nighttime sleep recordings start around 4 hours after caffeine/placebo intake Structure and intensity of sleep is measured by polysomnography. We focus on changes in deep sleep.
- Secondary Outcome Measures
Name Time Method Change in hormonal profile after caffeine intake (vs. placebo) Per condition (caffeine and placebo) 8 saliva samples (taken around 250 minutes, 230 minutes, 165 minutes, 115 minutes, 65 minutes and 15 minutes before bedtime, and 490 minutes and 520 minutes after bedtime) Hormonal levels are measured in saliva samples. We focus on time of melatonin onset (higher values indicate later time).
Change in viglance performance after caffeine intake (vs. placebo) Performance is measured 3 times in each condition (around 85 minutes, 200 minutes and 730 minutes after treatment) Vigilance performance is measured by reaction time patterns in a psychomotor vigilance task
Change in subjective sleepiness after caffeine intake (vs. placebo) Per condition (caffeine and placebo) 8 times (around 250 minutes, 230 minutes, 165 minutes, 115 minutes, 65 minutes and 15 minutes before bedtime, and 490 minutes and 520 minutes after bedtime) Sleepiness is measured by a questionnaire (Karolinska Sleepiness Scale, KSS). Higher scores on KSS (range between 1 and 9) represent higher sleepiness.
Change in pattern separation performance after caffeine intake (vs. placebo) Performance is measured 3 times in each condition (around 20 minutes before treatment and 220 minutes and 770 minutes) Cognitive performance is measured by the lure discrimination index and the recognition performance for repeat items.
Change in working memory performance after caffeine intake (vs. placebo) Performance is measured 3 times in each condition (around 45 minutes, 180 minutes and 780 minutes after treatment) Working performance is measured by accuracy in an n-back task (%of correct responses in 2-back versus 0-back)
Change in subjective sleep quality after caffeine intake (vs. placebo) Per condition around 480 minutes after bedtime Subjective sleep quality is measured by the Leeds Sleep Evaluation Questionnaire (LSEQ). Four different scales are evaluated: a) Getting to Sleep (range: 1-100, where lower values represent more difficulties to fall asleep), b) Quality of Sleep (range: 1-100, where lower values represent lower quality), c) Awake Following Sleep (range: 1-100, where lower values represent problems to wake up), and d) Behavior Following Wakening (range: 1-100, where lower values represent more sleepiness after awakening).
Change in cerebral blood flow once after placebo, once after caffeine (start of measurements around 60 minutes after treatment once after placebo, once after caffeine) Using magnetic resonance imaging (MRI), we measure levels of cerebral blood flow in the brain during rest.
Change in declarative memory performance after caffeine intake (vs. placebo) Performance is measured 3 times in each condition (around before 40 minutes before treatment and 210 and 760 minutes after treatment) Performance is quantified by assessing the course of the number of words recalled from a list of words (learned before treatment)
Change in mental effort during cognitive performance (working memory) after caffeine intake (vs. placebo) Mental effort is measured 3 times in each condition (around 70 minutes, 200 minutes and 800 minutes after treatment) Mental effort is measured by visual analogue scales targeting satisfaction, concentration, exhaustion and motivation. Scores range from 0-100. Higehr scores indicate higher levels on these scales.
Change in well-being after caffeine intake (vs. placebo) Per condition (caffeine and placebo) 8 times (around 250 minutes, 230 minutes, 165 minutes, 115 minutes, 65 minutes and 15 minutes before bedtime, and 490 minutes and 520 minutes after bedtime) Well-being is quantified as mean of three visual analogue scales targeting tension, mood and physical comfort. Scores range from 0-100. Higher scores indicate better well-being.
Trial Locations
- Locations (1)
Centre for Chronobiology
🇨🇭Basel, Switzerland