The Effects of Orthostatic Hypotension on Cognition in Parkinson's Disease

描述（由申请方提供）：申报的目的是研究直立性低血压（OH）对帕金森病（PD）患者认知的影响。PD中OH的患病率估计为20%至60%，这表明需要对其影响进行全面了解。最可能的病因是影响心率变异性和心输出量的心交感神经病。多巴胺能药物也可能在PD中加重OH中发挥作用。到目前为止，没有研究调查的急性影响OH对认知的PD。本研究将使用自主神经功能的客观指标，包括心电图、动脉压和经颅多普勒血流仪，以评估60度头高位倾斜对交感神经激活和重力代偿反应的影响。这些生理测量结果将根据仰卧位和倾斜位的几种神经心理学测试措施进行分析。参与者组将包括OH PD患者、无OH PD患者和人口统计学匹配的血压正常对照参与者。先前的研究表明，OH会导致直立位置的脑灌注不足，引起头晕、头晕和疲劳的症状。假设患有OH的PD参与者在倾斜时将在认知功能的几个领域中显示出受试者内的改善，并且患有OH的PD参与者在仰卧时将表现出比没有OH的PD参与者和正常对照参与者更差的总体表现。测试措施将包括对工作记忆、注意力、执行功能的评估，以及对情绪和日常生活活动的评估。PD中已报告了各种认知缺陷，一小部分研究表明，OH的PD患者在几个领域表现较差。通过了解OH对PD认知的影响，强调控制对姿势变化的代偿反应将使PD患者的生活质量提高，并具有更多的独立性。此外，保持足够的脑血流量可以在疾病期间获得更好的认知能力。

DESCRIPTION (provided by applicant): The goal of the proposed application is to investigate the effects of Orthostatic Hypotension (OH) on cognition in Parkinson's Disease (PD). Prevalence estimations of OH in PD range from 20 to 60%, indicating a need for a full understanding as to its effects. The most likely etiology is a cardiac sympathetic neuropathy affecting heart-rate variability and cardiac output. Dopaminergic medications may also play a role in exacerbating OH in PD. To date, no study has investigated the acute effects of OH on cognition in PD. This study will use objective measures of autonomic function, including electrocardiogram, arterial pressures, and transcranial Doppler flowmetry to assess the effects of a sixty-degree head-up tilt on sympathetic activation and gravitational compensatory responses. These physiological measurements will be analyzed against several neuropsychological test measures administered in both the supine and tilted positions. The participant groups will include PD patients with OH, PD patients without OH, and demographically matched normotensive control participants. Previous research suggests that OH will lead to cerebral hypoperfusion in the upright position, inducing symptoms of lightheadedness, dizziness, and fatigue. It is hypothesized that PD participants with OH will show within- subject detriments in several domains of cognitive function while tilted, and that PD participants with OH will demonstrate poorer overall performance than both PD participants without OH and normal control participants while supine. Test measures will include assessments of working memory, attention, executive function, as well as assessments of mood and activities of daily living. A variety of cognitive deficits have been reported in PD, and a small body of research suggests that PD patients with OH demonstrate poorer performance across several domains. By understanding the effects of OH on cognition in PD, emphasis on controlling compensatory responses to postural change will allow for an increased quality of life with more independence. Furthermore, maintaining adequate cerebral blood flow may allow for better cognitive abilities for the duration of the disorder.