Campbell S S, Murphy P J
Department of Psychiatry, Cornell University Medical College, White Plains, New York, USA.
J Am Geriatr Soc. 1998 Apr;46(4):458-62. doi: 10.1111/j.1532-5415.1998.tb02466.x.
Although changes in the circadian timing system are thought to be a major factor in the decline of sleep quality that often accompanies aging, few reports have actually examined this relationship in detail. Because some treatments for age-related insomnia are based on putative circadian changes, it is important to expand the limited database that specifically addresses this issue. This study examined age-related changes in sleep, and relationships between those sleep changes and alterations in the circadian timing system, in a group of middle-aged and older subjects.
Sixty healthy men and women between the ages of 40 and 84 were studied. A subset of older subjects (< 65 years) had reported sleep disturbance for at least 1 year before participation. Polysomnography was obtained, and body core temperature was recorded continuously for 24 hours. All recordings took place in the Laboratory of Human Chronobiology, Department of Psychiatry, Cornell University Medical College.
There were no differences in sleep quality between middle-aged and non-sleep-disturbed older subjects. However, timing of the minimum body temperature was earlier in the older non-sleep-disturbed subjects than in the middle-aged group. In contrast, sleep-disturbed older people had shorter total sleep times, reduced sleep efficiency, more waking time after sleep onset, and a reduced proportion of REM sleep compared with non-sleep-disturbed older subjects. Yet, there were no differences between the two older groups in the rhythm of body temperature. For the entire group, age was correlated negatively with total sleep time, sleep efficiency, percentage of stage 2 sleep, and the timing of the temperature minimum.
The results support the widely held notion that sleep and circadian rhythm changes occur with aging. However, the hypothesis that age-related changes in sleep may be associated with aging of the circadian system was supported only to a limited degree, suggesting that age-related sleep disturbance is likely to have multiple causes. Thus, treatment strategies that incorporate a combination of interventions may be the most effective.
尽管昼夜节律系统的变化被认为是睡眠质量下降的一个主要因素，而睡眠质量下降常伴随衰老出现，但实际上很少有报告详细研究这种关系。由于一些治疗与年龄相关失眠的方法是基于假定的昼夜节律变化，因此扩大专门针对这一问题的有限数据库很重要。本研究在一组中年和老年受试者中，研究了与年龄相关的睡眠变化，以及这些睡眠变化与昼夜节律系统改变之间的关系。
对60名年龄在40至84岁之间的健康男性和女性进行了研究。一部分老年受试者（<65岁）在参与研究前至少有1年的睡眠障碍报告。进行了多导睡眠图检查，并连续24小时记录身体核心温度。所有记录均在康奈尔大学医学院精神病学系人类时间生物学实验室进行。
中年和无睡眠障碍的老年受试者在睡眠质量上没有差异。然而，无睡眠障碍的老年受试者体温最低点的时间比中年组更早。相比之下，与无睡眠障碍的老年受试者相比，有睡眠障碍的老年人总睡眠时间更短、睡眠效率降低、入睡后清醒时间更多，且快速眼动睡眠比例降低。然而，两组老年受试者在体温节律上没有差异。对于整个组，年龄与总睡眠时间、睡眠效率、2期睡眠百分比以及温度最低点的时间呈负相关。
结果支持了普遍持有的观点，即睡眠和昼夜节律变化会随着衰老而发生。然而，与年龄相关的睡眠变化可能与昼夜节律系统衰老相关的假设仅在有限程度上得到支持，这表明与年龄相关的睡眠障碍可能有多种原因。因此，结合多种干预措施的治疗策略可能是最有效的。
