Effects of Bright Morning Light Exposure on Students' Stress, Mood, Anxiety, Sleep and, Circadian Rest-activity Cycle
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 125
- 试验地点
- 2
- 主要终点
- subjective stress level - baseline/post
研究概览
简要总结
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.
详细描述
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Double (Participant, Outcomes Assessor)
盲法说明
After randomisation to the two light intervention study arms, it is only explained to the test persons that the influence of regular exposure to light in the morning is being investigated.
The control light condition comprises dim, reddish light. The reddish color tone in this light intervention should mask allocation to the study arm. A no-light intervention group (study arm 3) will be established as an additional control condition.
Data analysis will be carried out by a member of the project team who is blinded to study arm allocation.
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •students from the faculty of medicine, pharmacy, and law
- •major exam at least 5 weeks ahead
- •major depressive disorder (PHQ-9): Score > 4
- •possession of smartphone and data plan
排除标准
- •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
结局指标
主要结局
subjective stress level - baseline/post
时间窗: 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
时间窗: 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
次要结局
- anxiety(Change from baseline STAI-trait sum score at the end of week 3)
- sleep quality - sleep onset latency(change of SOL at each night during the light intervention period up to 3 weeks)
- circadian rest/activity rhythm - interdaily stability(change of IV at each of the three light intervention weeks up to 3 weeks)
- sleep quality - total sleep time(Change of TST at each night during the light intervention period up to 3 weeks)
- circadian rest/activity rhythm - intradaily variability(change of IS at each of the three light intervention weeks up to 3 weeks)
- adverse effects - short-term(day 5)
- mood(Change from baseline CES-D sum score at the end of week 3)
- sleep quality(Change from baseline global PSQI score at the end of week 3)
- sleep quality - wake after sleep onset(change of WASO at each night during the light intervention period up to 3 weeks)
- sleep quality - sleep efficiency(change of SE at each night during the light intervention period up to 3 weeks)
- physiological stress reaction(Change from baseline hair cortisol level at the end of week 3)
- adverse effects - long-term(day 15)
研究者
Markus Canazei
Principal Investigator
Universitaet Innsbruck