Chronic Moderate Sleep Restriction in Older Long and Older Average Sleepers

描述(由申请人提供)：流行病学研究一直表明，自我报告的睡眠时间为7小时和8小时与死亡率和发病率的增加有关。与睡眠不足相关的风险与大量的实验文献一致，这些文献表明严重睡眠限制的有害影响。然而，对慢性适度睡眠限制的研究很少，从公共健康的角度来看，这种限制要普遍得多，因此也更重要。尽管流行病学数据表明，限制睡眠可能会促进长睡者的健康/长寿，但与长时间睡眠相关的风险几乎没有得到实验检验。老年人可能比年轻人更容易受到进一步睡眠障碍的负面影响，可能特别是通过炎症机制。如果像许多人假设的那样，长时间睡眠反映了潜在的发病率，那么长睡眠者的负面影响可能至少与普通睡眠者一样明显。另一方面，老年人可能会容忍(或受益于)适度的睡眠限制。老年人往往倾向于在床上花费过多的时间，特别是长睡者，额外的TIB可能会导致与年龄相关的睡眠碎片和发病率，这可以通过适度限制TIB来改善。在HL71560中，老年长睡眠者(8.5小时/晚)没有经历8周90分钟TIB限制的不良影响。HL71560扩展的目的是：(1)检查老年长睡眠者和老年平均睡眠者遵守60min TIB限制的能力；以及(2)比较12周60min TIB限制对老年长睡眠者和普通睡眠者健康相关措施的影响。这项研究还应该提供关于这些群体的睡眠习惯/信念的基因分型和定性信息。100名报告每晚睡眠8-9小时的老年人(60-80岁)和100名报告每晚睡眠6-7.25小时的同龄成年人将在4个试验点接受为期5年的检查。在两周的基线之后，参与者将被随机分配到两个12周的治疗组中的一个。(1)睡眠限制组(n=60名长睡眠者和n=60名平均睡眠者)将被分配到固定的睡眠-觉醒时间表，在该时间表中，卧床时间精确地比每个参与者的基线TIB减少60分钟。(2)对照组(40名长睡眠者和40名平均睡眠者)将不受睡眠限制，但也将遵循固定的睡眠时间表。睡眠将通过运动记录仪和每日日记进行持续评估。调查问卷将通过研究网站进行回答。衡量标准将包括体重、葡萄糖耐量、嗜睡、抑郁、生活质量、精神运动警觉、车祸发生率、疾病发生率和多种炎症标志物。在干预的第二周和第六周进行体检，一名研究监察员将进一步监测潜在的不良影响。将进行为期12个月的跟踪评估。拟议的临床试验将提供有史以来最全面的对慢性适度TIB限制的风险和好处的第一阶段评估。 与公共卫生相关：短睡眠者(6小时/晚)和长睡眠者(8小时/晚)的死亡率都较高，但对长期、中度睡眠不足对长睡眠者或普通睡眠者的影响的实验调查很少。一些科学家认为，老年人可能特别容易受到睡眠不足的负面影响，而另一些科学家则认为，许多老年人在床上花费的时间太多，适度减少床上时间有助于提高他们的睡眠质量，甚至可能促进健康和长寿，特别是对长睡者来说。我们将在全美4个地点进行一项为期5年的大型(200人)随机对照研究，以检验与老年平均睡眠者相比，卧床时间减少1小时12周对多种与健康相关的结果是负面还是正面影响，包括炎症、嗜睡、体重、情绪、血糖调节、生活质量、疾病发生率和车祸发生率。

DESCRIPTION (provided by applicant): Epidemiologic studies have consistently shown that self-reported sleep durations of <7 hr and >8 hr are associated with increased mortality and morbidity. The risks associated with short sleep are consistent with a vast experimental literature indicating detrimental effects of profound sleep restriction. However, there has been little study of chronic moderate sleep restriction, which is far more common, and thus more important from a public health standpoint. The risks associated with long sleep have scarcely been experimentally examined, though epidemiologic data suggest sleep restriction might promote health/longevity in long sleepers. Older adults might be more vulnerable than young adults to negative effects of further sleep impairment, perhaps particularly via inflammatory mechanisms. Negative effects might be at least as evident in long sleepers as in average sleepers if long sleep reflects underlying morbidity, as many have posited. On the other hand, older adults might tolerate (or benefit) from moderate sleep restriction. Older adults often tend to spend excessive time in bed (TIB), particularly long sleepers, and extra TIB could contribute to age-related sleep fragmentation and morbidity, which could be ameliorated with modest TIB restriction. In HL71560, older long sleepers (> 8.5 hr/night) experienced no adverse effects of 8 wk of 90-min TIB restriction. The aims of this expansion of HL71560 are: (1) to examine the ability of older long sleepers and older average sleepers to adhere to 60 min TIB restriction; and (2) to contrast effects of 12 weeks of 60 min TIB restriction on health-related measures in older long vs. average sleepers. The study should also provide genotyping and qualitative information about habits/beliefs about sleep in these groups. One hundred older adults (ages 60-80 yr) who report sleeping 8-9 hr per night and 100 adults of the same age range who report sleeping 6-7.25 hr per night will be examined at 4 experimental sites over 5 years. Following a 2-week baseline, participants will be randomly assigned to one of two 12-week treatment groups. (1) A sleep restriction group (n=60 long sleepers and n=60 average sleepers) will be assigned to a fixed sleep- wake schedule, in which time in bed is reduced precisely 60 min below each participant's baseline TIB. (2) A control group (n=40 long sleepers and n=40 average sleepers) will have no sleep restriction, but will also follow a fixed sleep schedule. Sleep will be assessed continuously with actigraphy and a daily diary. Questionnaires will be answered via a study web site. Measures will include body weight, glucose tolerance, sleepiness, depression, quality of life, psychomotor vigilance, incidence of automobile accidents, incidence of illness, and multiple markers of inflammation. Physical exams during weeks 2 and 6 of the intervention and a study ombudsman will further monitor potential adverse effects. Follow-up assessments will be conducted for 12 months. The proposed clinical trial will provide the most comprehensive Phase 1 assessment of risks and benefits of chronic moderate TIB restriction ever conducted. PUBLIC HEALTH RELEVANCE: Higher rates of mortality have been found both in short sleepers (< 6 hr/night) and long sleepers (> 8 hr/night), but there has been little experimental investigation of the effects of chronic, moderate sleep loss in long or average sleepers. Some scientists argue that older adults might be particularly vulnerable to negative effects of sleep loss, whereas other scientists argue that many older adults spend too much time in bed, and that moderate reduction of time-in-bed could help increase the quality of their sleep, and could even promote health and longevity, particularly in long sleepers. At 4 sites across the US, we will conduct a large (200 people), randomized, controlled, 5-year study to examine whether a 1-hour reduction of time spent in bed for 12 weeks has negative or positive effects on multiple health-related outcomes, including inflammation, sleepiness, body weight, mood, glucose regulation, quality of life, incidence of illness, and incidence of automobile accidents in older long sleepers as compared to older average sleepers.