DIZZINESS IN OLDER PEOPLE

头晕和平衡失调的主诉在老年人中很常见，但往往很难确定原因。相关的跌倒和对跌倒的恐惧影响了他们的生活质量，限制了他们的日常活动。我们假设头晕和不平衡不是正常衰老的结果，而是涉及内耳和大脑的特定病理生理变化的结果。我们的目标是更好地了解老年人头晕和平衡失调的原因。我们建议继续对主诉头晕和平衡失调的患者和年龄匹配的对照组进行一项纵向研究，每年进行一次检查，包括定量的视觉前庭测试和姿势图。第一个具体目标是记录与正常衰老相关的前庭功能和平衡的变化；b)确定老年人头晕和平衡失调的常见原因的自然病史；以及c)记录头晕和不明原因失衡患者的临床过程。第二个目标是将正常受试者和进行尸检的患者的功能与形态联系起来，目的是通过内耳和大脑内可识别的变化来解释平衡的变化。临床诊断的准确性有多高？不明原因眩晕和失衡患者的内耳或大脑是否表现出与年龄匹配的对照组不同的变化？这项研究的独特之处在于a)纵向设计和b)尸检时的组织病理学结果与生前获得的定量测试信息的结果之间的相关性。之前很少有关于老年人头晕和失衡的纵向研究，也没有一项研究包括对听觉和前庭功能的连续测量，以及对平衡的定量测量、半定量的神经学检查和大脑的连续磁共振成像(MRI)。以往对患有平衡障碍的老年人的组织病理学研究主要集中在颞骨或大脑，但不是两者都有，缺乏详细的临床数据，很少包含有关一生中前庭功能的定量信息。通过继续对仔细研究的老年患者和对照进行这项纵向研究，我们的多学科研究团队处于实现我们目标的良好地位。

Complaints of dizziness and disequilibrium are common in older people yet it is often difficult to determine the cause. Associated falls and fear of falling affect the quality of their lives and limit their daily activities. We hypothesize that dizziness and disequilibrium are not a result of normal aging but rather the result of specific pathophysiologic changes involving the inner ear and brain. Our goal is to better understand the causes of dizziness and disequilibrium in older people. We propose to continue a longitudinal study of patients complaining of dizziness and disequilibrium and age-matched controls with yearly examinations including quantitative visual-vestibular testing and posturography. The goal of the first specific aim is to a) document changes in vestibular function and balance associated with normal aging; b) define the natural history of the common causes of dizziness and disequilibrium in older people; and c) document the clinical course in patients with dizziness and disequilibrium of unknown cause. The second aim is to correlate function with morphology in normal subjects and patients who come to postmortem examination with the goal of explaining changes in balance in terms of identifiable changes within the inner ear and brain. How accurate were the clinical diagnoses? Do patients with dizziness and disequilibrium of unknown cause show changes in the inner ear or brain different from those of age-matched controls? The unique features of this research are a) the longitudinal design and b) the correlation of histopathologic findings at the time of postmortem examination with the results of quantitative test information obtained during life. There have been few prior longitudinal studies of dizziness and imbalance in older people and none that includes serial measurements of auditory and vestibular function, and quantitative measurements of balance, semiquantitative neuro-logical examinations and serial magnetic resonance images (MRI's) of the brain. Prior histopathological studies in older people with balance dysfunction have focused on the temporal bone or brain but not both, have lacked detailed clinical data, and rarely have contained quantitative information regarding vestibular function during life. By continuing this longitudinal study of carefully studied older patients and controls, our multidisciplinary research team is in a good position to achieve our goals.