SLEEP & MENTAL FUNCTION IN THE AGED--ANABOLIC INFLUENCE

老年人抱怨记忆力丧失、睡眠障碍、虚弱和失落 瘦体重；与年龄相关的认知能力、睡眠下降 数量和质量、瘦体重(LBM)和合成代谢激素等 因为生长激素(GH)有很好的文献记载。初步证据来自 我们的数据库表明，这些变化可能是相互关联的。我们 观察到合成代谢状态(以血浆胰岛素样生长为指标 因子，或IGF)，与较好的 睡眠质量(增加慢波睡眠，减少觉醒，以及 减少睡眠的碎片化)和认知，特别是记忆 以及健康老年人的注意力。这些初步结果让我们得出了 假设衡量外周合成代谢状态(例如，性别 激素、LBM，特别是GH和IGF)可能是中枢神经系统的指标 老年人的系统(CNS)状态。虽然GH和IGF是众所周知的 它们与中枢神经系统功能的关系在很大程度上 已被忽略。在老年人中没有这样的研究，他们更有可能 睡眠和认知受损，生长激素和胰岛素样生长因子水平较低 比年轻人水平更高。拟议的研究将扩大我们现有的数据 基础阐明合成激素状态和睡眠之间的关系 来自我们的控制的子集的质量和认知功能 已有的健康老年人对照样本(n=280)。 我们的假设将在大约140名对照受试者中进行测试。至 评估合成代谢状态，将通过缓慢抽血泵采血 在24小时内。将对汇集的血浆进行24小时积分检测 生长激素、胰岛素样生长因子、皮质醇、游离睾酮(男性)和甲状腺水平 激素(T3、T4)。生长激素和睾酮的结合蛋白也将是 量过了。24小时尿雌酮和雌二醇会 以女性为衡量标准。瘦体重将通过生物阻抗来确定。 睡眠变量将包括睡眠阶段和清醒、睡眠 分段(阶段改变)和合并(休眠时间)，如 以及总的脑电增量活动(计算机得出)。两性关系 合成代谢状态和睡眠之间的关系将使用多个 回归技术。认知测试将包括Rivermead行为测试 记忆、痴呆症评定量表、配对伙伴学习任务、 工作记忆任务(词组)、选择性注意任务(简明测验 注意力)，以及语言流畅性测试。合成代谢之间的关系 地位和认知也将使用多元回归来确定 技巧。这些研究将确定合成代谢激素的水平， 与高睡眠质量和良好的认知功能有关 老年人。它们还将促进适当的GH和 旨在改善认知/睡眠的胰岛素样生长因子干预研究 高年级学生。我们更大的长期目标是阐明生长激素的作用 以及IGF和相关激素在衰老的神经生物学中的作用。

Older adults complain of memory loss, sleep disorders, frailty, and loss of lean body mass; age-related decreases in cognitive ability, sleep quantity and quality, lean body mass (LBM), and anabolic hormones such as growth hormone (GH) are well-documented. Preliminary evidence from our database suggests that these changes may be interrelated. We observed that anabolic status (as indexed by plasma insulin-like growth factor, or IGF), correlates significantly and positively with better sleep quality (increased slow wave sleep, decreased wakefulness, and decreased fragmentation of sleep) and with cognition, particularly memory and attention in healthy seniors. These preliminary results lead us to hypothesize that measures of peripheral anabolic status (e.g., sex hormones, LBM, and particularly GH and IGF) may index central nervous system (CNS) status in older adults. While GH and IGF are well-known to index somatic status, their relationship to CNS function has been largely ignored. There are no such studies in the elderly, who are more likely to suffer from impaired sleep and cognition and have lower GH and IGF levels than the young. The proposed study will expand our existing data base to clarify the relationships among anabolic hormone status, sleep quality and cognitive function in subsets of controls drawn from our already-existing samples of healthy older control adults (n=280). Our hypotheses will be tested in approximately 140 control subjects. To evaluate anabolic status, blood will be sampled via slow withdrawal pump across 24-hours. Pooled plasma will be assayed for integrated 24-hour levels of GH, IGF, cortisol, free testosterone (in men), and thyroid hormones (T3,T4). Binding proteins for GH and testosterone will also be measured. Twenty-four hour urinary estrone and estradiol will be measured in women. Lean body mass will be determined via bio-impedance. Sleep variables will include stages of sleep and wakefulness, sleep fragmentation (stage changes) and consolidated (sleep period time), as well as total EEG delta activity (computer derived). Relationships between anabolic status and sleep will be identified using multiple regression techniques. Cognitive tests will include Rivermead Behavioral Memory, Dementia Rating Scale, a paired associates learning task, a working memory task (Verbal Sets), a selective attention task (Brief Test of Attention), and a verbal fluency test. Relationships between anabolic status and cognition will also be identified using multiple regression techniques. These studies will identify levels of anabolic hormones that are associated with high sleep quality and good cognitive function in senior adults. They will also foster the design of appropriate GH and IGF intervention studies targeted at improving cognition/sleep in seniors. Our larger long-term objective is to elucidate the role of GH and IGF and related hormones in the neurobiology of aging.