Breathing Instability and Upper Airway Obstruction During Sleep: Effect of Aging

描述(由申请人提供)： 项目摘要睡眠呼吸暂停低通气综合征(SAS)是一种常见的疾病，老年人的患病率高于中年人。这项建议旨在研究睡眠期间呼吸不稳定易感性和上呼吸道塌陷易感性的年龄差异。将调查以下具体目标。具体目标1是确定特定年龄对睡眠期间周期性呼吸易感性的影响。为此，我们将在压力支持模式下使用无创正压通气(NIPPV)来诱导周期性呼吸(作为呼吸不稳定的指标)。具体目标2是确定睡眠期间年龄对上呼吸道力学的特定影响。我们将检验这一假设，即老年人的咽后腭部顺应性和被动临界闭合压力比年轻人更高。因此，我们将在基线条件下和低张(被动)条件下测量临界闭合压力，以确定在有或没有主动神经肌肉控制的情况下崩溃程度的差异。使用鼻咽镜，我们还将测量睡眠期间的咽部顺应性。具体目标3是确定NREM睡眠期间呼吸机输出减少和上呼吸道通畅对年龄的特定影响。我们假设，与年轻人相比，呼气性咽部狭窄在老年人中更为明显。我们将调查在鼻腔机械过度换气后诱发性低碳酸血症的条件下，老年人的咽部横截面积是否较小。拟议的研究解决了一个重要的临床问题，并将进一步加深我们对睡眠呼吸暂停的发病机制的理解。 公共卫生相关性： 项目叙事睡眠障碍呼吸(SDB)在中老年退伍军人中很常见。许多人患有可能会放大睡眠期间呼吸不稳定的共病情况。这一建议将进一步加深我们对导致老年人睡眠呼吸暂停的机制的理解。我们预计，我们的发现将为睡眠呼吸暂停综合征的预防和管理提供新的方法基础。

DESCRIPTION (provided by applicant): Project Abstract Sleep apnea-hypopnea syndrome (SAS) is common and has a higher prevalence in the elderly relative to middle-aged individuals. This proposal is concerned with investigating the age-specific differences in susceptibility to breathing instability and upper airway susceptibility to collapse during sleep. The following specific aims will be investigated. Specific Aim 1 is to determine the age-specific effect on periodic breathing susceptibility during sleep. To this end, we will use non-invasive positive pressure ventilation (NIPPV) in the pressure-support mode to induce periodic breathing (as an index of breathing instability). Specific Aim 2 is to determine the age-specific effect on upper airway mechanics during sleep. We will test the hypothesis that pharyngeal retro- palatal compliance and the passive critical closing pressure are higher in older adults as compared to young adults. Therefore, we will measure the critical closing pressure, under baseline conditions and under hypotonic (passive) conditions to establish differences in collapsibility with, and without, active neuromuscular control. Using naso- pharyngoscopy, we will also measure pharyngeal compliance during sleep. Specific Aim 3 is to determine the age-specific effects of reduced ventilatory motor output and upper airway patency during NREM sleep. We hypothesize that expiratory pharyngeal narrowing is more pronounced in older adults as compared to young adults. We will investigate whether the pharyngeal cross-sectional area under conditions of induced hypocapnic hypopnea, in the aftermath of nasal mechanical hyperventilation, is smaller in older adults. The proposed studies address a significant clinical problem and will further our understanding of the pathogenesis of sleep apnea PUBLIC HEALTH RELEVANCE: Project Narrative Sleep-disordered breathing (SDB) is common among middle-aged and older veterans. Many have co-morbid conditions that may amplify breathing instability during sleep. This proposal will further our understanding of the mechanisms that contribute to the development of sleep apnea in older adults. We anticipate that our finding will provide the basis for new approaches to the prevention and management of sleep apnea syndrome.