Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA.
Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA.
Lancet Neurol. 2014 Sep;13(9):904-12. doi: 10.1016/S1474-4422(14)70122-X. Epub 2014 Aug 7.
Sleep deprivation and fatigue are common subjective complaints among astronauts. Previous studies of sleep and hypnotic drug use in space have been limited to post-flight subjective survey data or in-flight objective data collection from a small number of crew members. We aimed to characterise representative sleep patterns of astronauts on both short-duration and long-duration spaceflight missions.
For this observational study, we recruited crew members assigned to Space Transportation System shuttle flights with in-flight experiments between July 12, 2001, and July 21, 2011, or assigned to International Space Station (ISS) expeditions between Sept 18, 2006, and March 16, 2011. We assessed sleep-wake timing objectively via wrist actigraphy, and subjective sleep characteristics and hypnotic drug use via daily logs, in-flight and during Earth-based data-collection intervals: for 2 weeks scheduled about 3 months before launch, 11 days before launch until launch day, and for 7 days upon return to Earth.
We collected data from 64 astronauts on 80 space shuttle missions (26 flights, 1063 in-flight days) and 21 astronauts on 13 ISS missions (3248 in-flight days), with ground-based data from all astronauts (4014 days). Crew members attempted and obtained significantly less sleep per night as estimated by actigraphy during space shuttle missions (7·35 h [SD 0·47] attempted, 5·96 h [0·56] obtained), in the 11 days before spaceflight (7·35 h [0·51], 6·04 h [0·72]), and about 3 months before spaceflight (7·40 h [0·59], 6·29 h [0·67]) compared with the first week post-mission (8·01 h [0·78], 6·74 h [0·91]; p<0·0001 for both measures). Crew members on ISS missions obtained significantly less sleep during spaceflight (6·09 h [0·67]), in the 11 days before spaceflight (5·86 h [0·94]), and during the 2-week interval scheduled about 3 months before spaceflight (6·41 h [SD 0·65]) compared with in the first week post-mission (6·95 h [1·04]; p<0·0001). 61 (78%) of 78 shuttle-mission crew members reported taking a dose of sleep-promoting drug on 500 (52%) of 963 nights; 12 (75%) of 16 ISS crew members reported using sleep-promoting drugs.
Sleep deficiency in astronauts was prevalent not only during space shuttle and ISS missions, but also throughout a 3 month preflight training interval. Despite chronic sleep curtailment, use of sleep-promoting drugs was pervasive during spaceflight. Because chronic sleep loss leads to performance decrements, our findings emphasise the need for development of effective countermeasures to promote sleep.
The National Aeronautics and Space Administration.
睡眠不足和疲劳是宇航员常见的主观抱怨。之前对太空睡眠和催眠药物使用的研究仅限于飞行后的主观调查数据或少数机组人员的飞行中的客观数据收集。我们旨在描述短期和长期太空飞行任务中宇航员的代表性睡眠模式。
在这项观察性研究中，我们招募了被分配到航天飞机飞行任务的机组人员，这些任务中有飞行期间的实验，时间为 2001 年 7 月 12 日至 2011 年 7 月 21 日，或被分配到国际空间站（ISS）任务，时间为 2006 年 9 月 18 日至 2011 年 3 月 16 日。我们通过腕动计客观评估睡眠-觉醒时间，并通过每日日志评估主观睡眠特征和催眠药物使用情况，包括飞行中和地球数据收集间隔期间：在发射前约 3 个月的 2 周内、发射前 11 天至发射日，以及返回地球后的 7 天内。
我们从 80 次航天飞机任务（26 次飞行，1063 个飞行日）中的 64 名宇航员和 13 次国际空间站任务（3248 个飞行日）中的 21 名宇航员那里收集了数据，所有宇航员都有地面数据（4014 天）。与任务后的第一周（8.01 小时 [0.78]，6.74 小时 [0.91]）相比，航天飞机任务期间（7.35 小时 [0.51]，6.04 小时 [0.72]）和飞行前约 3 个月（7.40 小时 [0.59]，6.29 小时 [0.67]），航天飞机任务期间（7.35 小时 [0.47]，5.96 小时 [0.56]），以及在飞行前 11 天（7.35 小时 [0.51]，6.04 小时 [0.72]），机组人员尝试并通过腕动计获得的夜间睡眠时间明显减少；与任务后的第一周相比，ISS 任务期间（6.09 小时 [0.67]），飞行前 11 天（5.86 小时 [0.94]）和飞行前约 3 个月的 2 周间隔（6.41 小时 [0.65]），机组人员在任务后的第一周获得的睡眠时间明显减少（6.95 小时 [1.04]）；78 名航天飞机任务机组人员中有 61 名（78%）在 963 个飞行日中的 500 个（52%）报告服用了一剂促进睡眠的药物；16 名国际空间站机组人员中有 12 名（75%）报告使用了促进睡眠的药物。
不仅在航天飞机和国际空间站任务期间，而且在飞行前 3 个月的训练间隔期间，宇航员的睡眠不足都很普遍。尽管慢性睡眠不足，但在飞行期间仍普遍使用促进睡眠的药物。由于慢性睡眠不足会导致表现下降，因此我们的研究结果强调了开发有效对策促进睡眠的必要性。
美国国家航空航天局。
