Bright Light Intervention to Reduce Students' Stress
- Conditions
- Psychological StressPhysiological StressSleep Disorders, Circadian Rhythm
- Interventions
- Other: Bright light interventionOther: Reddish placebo light
- Registration Number
- NCT04900675
- Lead Sponsor
- Universitaet Innsbruck
- Brief Summary
Increased stress levels are a significant problem for many students and represent a risk factor for impaired mental and physical health as well as academic performance. Stress levels are particularly high during the preparation phase for major exams.
There is good evidence that light therapy is an effective treatment option to improve mood in affective disorders.
The present study aims at investigating the psychophysiological effects of a 3-week morning bright light exposure in reducing stress and stress-related problems in students preparing for major exams.
- Detailed Description
Increased students' stress represents a significant risk factor for impaired mental and physical health as well as academic performance. The World Mental Health Survey (WHO) reports a 12-month prevalence of mental illness of 20.3% among students, with anxiety disorders (14.7%), affective disorders (9.9%), and substance abuse (6.7%) being particularly prominent. Moreover, six out of 10 students suffer from impaired sleep quality.
Offering an effective treatment for stress-related symptoms in students is a challenge. In situations of intense stress, conventional methods such as relaxation and mindfulness-based programs often fail because of poor prior practice. Only a few students apply cognitive behavioral interventions. Although medication might decrease stress symptoms within days, the side effects of drugs cannot be ignored. Therefore, there is a need for effective and efficient treatment of acute stress symptoms in students.
Bright light therapy is an effective treatment for several mental disorders, e.g. affective disorders and sleep disorders. There is some evidence, that exposure to bright light may even reduce stress in patients with burnout symptoms. Thus, exposure to bright light may be a promising new option to reduce academic stress and improve mood and sleep parameters.
In the present study, a large-area desk lamp, which emits diffuse light and is controllable in its luminance and correlated color temperature is used. Study participants are randomly assigned to one of three study arms: (i) exposure to polychromatic light of 5,000 lux and 5,300 Kelvin, (ii) exposure to polychromatic light of 50 lux and 2,200 Kelvin, or (iii) no light intervention. Data collection takes place in winter periods.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 125
- students from the faculty of medicine, pharmacy, and law
- major exam at least 5 weeks ahead
- possession of smartphone and data plan
- major depressive disorder (PHQ-9): Score > 4
- suicidal ideation (BDI, Item i): Rating > 1
- seasonal affective disorder (PIDS-A): Score > 11
- taking medication which increases photo-sensitivity
- taking medication to increase cognitive performance
- starting or changing pharmacotherapy for affective disorders and anxiety disorders within the last two weeks
- changing of all kinds of medication within the last two weeks
- headache (PHQ-D, Item f): Rating "severly impaired"
- increased light sensitivity: Item "Wearing sunglasses outside on sunny days" is answered with 'often' or 'very often'
- currently undergoing psychotherapeutic treatment
- the presence of an eye disease for which light therapy is contraindicated
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description bright white light intervention Bright light intervention exposure to 5,000 lux with polychromatic white light with 5,300 Kelvin at eye level; light exposure starts immediately after awakening; light exposure takes place on weekdays (Monday till Friday) over a period of 3 weeks dim reddish light intervention Reddish placebo light exposure to 50 lux with polychromatic reddish light with 2,200 Kelvin at eye level; light exposure starts immediately after awakening; light exposure takes place on weekdays (Monday till Friday) over a period of 3 weeks
- Primary Outcome Measures
Name Time Method subjective stress level - baseline/post Change from baseline PSQ-20 sum score at the end of week 3 Perceived Stress Questionnaire (PSQ-20); scale: PSQ-20 sum score; range: 20 - 80; higher scores mean a higher subjective stress level
subjective stress level - on weekdays Change of daily PSQ-20 sum score at each weekday during the light intervention period up to 3 weeks Perceived Stress Questionnaire (PSQ-20); scale: PSQ-20 sum score; range: 20 - 80; higher scores mean a higher subjective stress level
- Secondary Outcome Measures
Name Time Method anxiety Change from baseline STAI-trait sum score at the end of week 3 State-Trait Anxiety Inventory (STAI - form Y) - 20 trait items; scale: STAI-trait sum score; range: 20 - 80; higher scores mean a higher subjective anxiety level
sleep quality - sleep onset latency change of SOL at each night during the light intervention period up to 3 weeks Wrist actimetry to measure daily sleep onset latency (SOL); scale: duration to fall asleep; range: \>0 (minutes); higher SOL means longer period to fall asleep
circadian rest/activity rhythm - interdaily stability change of IV at each of the three light intervention weeks up to 3 weeks Circadian rest-activity cycle parameter interdaily stability (IS) derived from weekly wrist actimetry data; scale: real number; range: 0 -1; higher IS means a higher stability in daily rest-activity cycles
sleep quality - total sleep time Change of TST at each night during the light intervention period up to 3 weeks Wrist actimetry to measure daily total sleep time (TST); scale: sleep duration; range: \>0 (minutes); higher TST means longer sleep period
circadian rest/activity rhythm - intradaily variability change of IS at each of the three light intervention weeks up to 3 weeks Circadian rest-activity cycle parameter intradaily variability (IV) derived from averaged wrist actimetry data over a period of 1 week; scale: real number; range: 0 - 2; higher IV means a higher variability in 24-h rest-activity cycle
adverse effects - short-term day 5 astenopic complaints measured with 12 items; scale: sum score; range: 10 - 60; higher sum score means more astenopic complaints
mood Change from baseline CES-D sum score at the end of week 3 Center for Epidemiologic Studies Depression Scale (CES--D); scale: CES-D sum score; range: 0 - 60; higher scores mean a higher subjective depression level
sleep quality Change from baseline global PSQI score at the end of week 3 Pittsburgh Sleep Quality Index (PSQI); scale: global PSQI score; range: 0 - 21; higher scores mean a lower subjective sleep quality
sleep quality - wake after sleep onset change of WASO at each night during the light intervention period up to 3 weeks Wrist actimetry to measure daily wake after sleep onset (WASO); scale: duration of being awake during sleep period; range: greater than or equal to 0 (minutes); higher WASO means longer wake periods after sleep onset
sleep quality - sleep efficiency change of SE at each night during the light intervention period up to 3 weeks Wrist actimetry to measure daily sleep efficiency (SE); scale: percentage; range: 0 - 100; higher SE means a higher undisturbed sleep
physiological stress reaction Change from baseline hair cortisol level at the end of week 3 cortisol level measured from hair sample; scale: real number (pg/mg); range: \>0; higher hair cortisol level means higher physiological stress
adverse effects - long-term day 15 astenopic complaints scale measured with 12 items: sum score; range: 10 - 60; higher sum score means more astenopic complaints
Trial Locations
- Locations (1)
University of Innsbruck
🇦🇹Innsbruck, Tyrol, Austria