ADVANCED SLEEP PHASE IN THE ELDERLY-- CIRCADIAN ETIOLOGY

调查数据显示，超过15%的原本健康的老年人 报告曾扰乱睡眠。最常见的投诉是 睡眠时间不当，即清晨醒得很早 在晚上伴随着深深的困倦。这一阶段 一些生理和认知的昼夜节律研究进展 变量。动物研究表明，这些与年龄相关的进展 昼夜节律系统的夹带阶段伴随着缩短 昼夜节律起搏器的内在周期。我们发现， 的属性也有相应的年龄相关变化 人类的昼夜节律系统，可导致 昼夜节律起搏器的输出和通常可用的时间 睡着和醒着。 在此基础上，提出了四个可检验的假设：(1) 内源性昼夜节律起搏器的内在周期较短 在年龄较大的受试者中比在年轻人中；(2) 内源性体温昼夜节律呈正相关 它的内在周期，以及清晨的主要抱怨 觉醒与一段比平均时间短的 内源性昼夜节律起搏器；(3)睡眠延迟、睡眠效率 REM睡眠的时间随内源性昼夜节律的变化而不同 更年轻的受试者。 建议进行一项实验，使用新的方法来允许准确和 可靠地评估内源性昼夜节律的内在周期 起搏器、起搏器与牵引性昼夜节律时相的关系 这两个参数都随着年龄的增长而增加。在这个实验中， 年龄相关变化对内源性昼夜节律起搏器和心脏功能的影响 它对睡眠结构和昼夜相依睡眠的影响 将对干扰进行评估。 这项工作对老年学医学具有重要意义。沉睡 老年人的疾病是导致老年人生活质量下降的一个重要原因 生活在其他健康的人身上。它们经常会导致 过量服用安眠药，有不幸的生理方面 效果。对神经生理机制有更深入的了解 老年人潜在的睡眠障碍以及对非睡眠障碍的理解 侵入性方法为缓解这些疾病提供了实质性的希望 改善老年人的健康。

Survey data reveal that more than 15% of otherwise healthy older people report having disturbed sleep. The most frequent complaint is an inappropriate timing of sleep, i.e., a very early morning awakening accompanied by profound sleepiness during the evening hours. This phase advance in the circadian rhythms of a number of physiologic and cognitive variables. Animals studies indicate that these age-related advances in the entrained phase of the circadian system are accompanied with a shortening of the intrinsic period of the circadian pacemaker. We have found that there are corresponding age-related changes in the properties of the circadian system in humans that can results in misalignment between the output of the circadian pacemaker and the usual the times available for sleeping and waking. On the basis of our results, four testable hypotheses are proposed: (1) that the intrinsic period of the endogenous circadian pacemaker is shorter in older subjects than in young adults; (2) that the entrained phase of the endogenous circadian rhythm of body temperature is positively correlated with its intrinsic period, and that the primary complaint of early morning awakening is associated with a shorter-than-average period of the endogenous circadian pacemaker; (3) that sleep latency, sleep efficiency, and the timing of REM sleep vary with endogenous circadian phase than is that of younger subjects. An experiment is proposed using new methodologies to allow the accurate and reliable assessment the intrinsic period of the endogenous circadian pacemaker, its relation to entrained circadian phase, and the changes in both of these parameters with advancing age. In this experiment, the influence of age-related changes in the endogenous circadian pacemaker and its impact on sleep structure and circadian phase-dependent sleep disruption will be assessed. This work has significant implications for gerontologic medicine. Sleep disorders in older people are an important cause of a diminished quality of life in otherwise healthy people. They frequently lead to an overconsumption of sleep medications with unfortunate physiological side effects. Greater understanding of the neurophysiologic mechanism underlying sleep disorders in older people as well as understanding of non- invasive methods for their alleviation offer substantive promise for improved health of older people.