Effect of Heat Exposure on Cognition in Persons with Higher Cord Lesions

热暴露对高位脊髓损伤患者认知的影响

• 批准号: 9067159
• 负责人: John P Handrakis
• 金额: --
• 依托单位: JAMES J PETERS VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2018-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9067159
• 关键词: Activities of Daily Living; Address; Adverse effects; Age; Arrhythmia; Attention; Awareness; Behavior; Blood; Blood Pressure; Body Composition; Body Temperature; Cardiac; Centers for Disease Control and Prevention (U.S.); Cervical; Cessation of life; Chronic; Cognition; Cognitive; Comparative Study; Confusion; Data; Depressed mood; Distal; Encephalopathies; Environment; Esthesia; Exposure to; Feeling; Gender; Goals; Headache; Heart Arrest; Heating; Hour; Hyperthermia; Impairment; Individual; Infection; Interruption; Intervention; Judgment; Kidney Failure; Knowledge; Lesion; Limb structure; Liver Failure; Maintenance; Measurement; Measures; Medical; Mental Depression; Methodology; Motor; Nausea; Normal Range; Pain; Paraplegia; Pathway interactions; Peripheral; Persons; Pharmaceutical Preparations; Physiologic Thermoregulation; Physiological; Pilot Projects; Positioning Attribute; Quadriplegia; Quality of life; Recruitment Activity; Reporting; Research; Risk; Sensory; Shivering; Short-Term Memory; Signs and Symptoms; Skin; Skin Temperature; Societies; Spinal cord injury; Sterile coverings; Stupor; Sunlight; Sweat; Sweating; Temperature; Thermogenesis; Thoracic Injuries; Time; Unconscious State; Vasodilation; Ventricular Fibrillation; Veterans; Viscosity; Work; base; carbohydrate metabolism; cognitive function; cognitive performance; diet and exercise; disorder prevention; executive function; improved; insight; instrumentation; insulin sensitivity; lean body mass; memory process; mental function; metabolic rate; natural hypothermia; processing speed; prospective; rectal; response; safety study; sound; spasticity; therapy development; thermal stress; vasoconstriction; warm temperature

After spinal cord injury (SCI), particularly cervical and high thoracic injuries, the motor, sensory, and sympathetic pathways necessary for effective thermoregulation are interrupted, resulting in an impaired ability to maintain core body temperature (Tcore) when exposed to challenges in environmental temperature. Control of distal extremity vasoconstriction (heat conservation) and shivering thermogenesis (heat production) are impaired, and the ability to maintain a constant Tcore is compromised. In addition, changes in body composition (loss of lean body mass) and medications commonly prescribed in persons with SCI may lower metabolic rate and further depress Tcore. Persons with tetraplegia often report “feeling cold,” frequently present with subnormal Tcore (35.5-36.5°C), and are particularly vulnerable to hypothermia (Tcore<35°C), even at temperatures that are comfortable for able-bodied (AB) individuals. The deleterious effects of hypothermia are well appreciated in AB persons with documented progressive decline in various aspects of cognitive performance associated with the magnitude of the depression in Tcore. However, the potential beneficial effects of increasing subnormal Tcore to euthermic levels on cognitive function of those with tetraplegia are not known. In our current submission, we are proposing a prospective two-group comparative study to compare the physiological and cognitive responses to warm exposure in persons with SCI who have subnormal Tcore and in AB persons who are euthermic. Twenty subjects with SCI (C3-T4, AIS A & B; Tcore <37°C) and 20 age/gender-matched AB control subjects will be recruited for study. Subjects will be placed in a thermoneutral (27°C) environment for instrumentation. Measurements of Tcore (rectal thermocouple), skin temperature (skin thermocouple), sweat rate (QSweat methodology), and thermal sensitivity (9-point thermal sensation scale) will be made during 15 minutes of baseline (27°C) and during up to 120 minutes of warm (35°C) temperature exposure while in the seated position. Cognitive performance will be assessed twice, at baseline and after Tcore rises 0.5°C or at the end of the warm challenge. The primary dependent variables will be Tcore and cognitive performance. The secondary dependent variables will be measures of autonomic adaption to a warm environment and include distal skin temperature, sweat rate, and thermal sensitivity. Specific Aims: During exposure to a warm environment (35°C) for up to 120 min in the seated position: Primary Specific Aim: To determine if 2 hours of warm exposure will cause a 0.5°C increase in Tcore and favorably effect cognitive performance (attention, working memory, processing speed, and executive function). Primary Hypotheses: Based on our pilot data: (1) Eighty percent of persons with tetraplegia will demonstrate an increase of 0.5°C in Tcore while none of the AB controls will demonstrate such an increase in Tcore; (2) Eighty percent of persons with tetraplegia will have an increase of at least one T-score in Stroop Interference scores (a validated measure of executive function) while none of the AB controls will demonstrate a change in cognitive performance. Secondary Specific Aims: To determine changes in: (1) The average of distal skin temperatures; (2) Sweat rate; and (3) Subjective rating of thermal sensitivity. Secondary Hypotheses: Persons with tetraplegia will have less of a percent change in average distal skin temperatures and sweat rate, and will report blunted ratings of thermal sensitivity compared to that of AB controls. Our proposed study will confirm our preliminary observations in persons with SCI who have subnormal Tcore to demonstrate in a more definitive manner that cognitive function will be improved by raising Tcore to normal. By rapidly and dramatically reversing the impairment in cognitive function by raising Tcore about 0.5°C to euthermic values, we would anticipate greater functional capacity and independence, enhanced reintegration into society, and improved quality of life, albeit these endpoints are beyond the scope of the current proposal.

脊髓损伤（SCI），尤其是宫颈和高胸腔损伤后，运动，感觉和 有效温度调节所需的交感神经途径被中断，导致能力受损 在面临环境温度挑战时，保持核心体温（TCORE）。控制 远端血管收缩（节能）和发抖的热发生（热产生）是 受损，维持恒定TCORE的能力受到损害。另外，身体变化 成分（瘦体重的损失）和通常在SCI的人处方的药物可能会降低 代谢率和进一步降低TCORE。四边形的人经常报告“感觉冷”，经常 存在下正常Tcore（35.5-36.5°C），并且特别容易受到低温（Tcore <35°C）的影响 即使在适合健全的（AB）个体的温度下。有害影响 体温过低的AB患者受到了很好的赞赏。 与TCORE抑郁症的幅度相关的认知表现。但是，潜力 提高tcore下tcore升级到安特素水平对患有认知功能的有益影响 四脑尚不清楚。在目前的提交中，我们提出了一个前瞻性的两组比较 研究以比较患有SCI的人的身体和认知反应 tcore和ab的腹部正常。二十个具有SCI的受试者（C3-T4，AIS A＆B; TCORE <37°C）和20岁/性别匹配的AB对照受试者将被招募进行研究。受试者将被放置在 用于仪器的热中性（27°C）环境。 TCORE（直肠热电偶）的测量 温度（皮肤热电偶），出汗率（QWEAT方法）和热敏性（9点热量 感觉量表将在基线15分钟（27°C）和最多120分钟内进行。 （35°C）在座位位置时温度暴露。认知表现将两次评估 基线和TCORE上升为0.5°C或在温暖挑战结束时。主要因变量将 表现出色和认知表现。次级因变量将是自主神经的度量 适应温暖的环境，包括远端皮肤温度，出汗率和热敏感性。 具体目的：在接触温暖的环境（35°C）期间，在座位上最多120分钟： 主要特定目的：确定2小时的温暖暴露是否会导致Tcore增加0.5°C 有利地影响认知表现（注意，工作记忆，处理速度和执行功能）。 主要假设：基于我们的试点数据：（1）八十％的四脑患者将证明 TCORE的增加0.5°C，而AB对照组都没有表现出Tcore的增加。 （2） 四十％患有四边形的人将在Stroop干扰中至少增加一个T分数 分数（对执行功能的验证测量），而AB控件都没有证明变化 认知表现。 次要特定目的：确定：（1）远端皮肤温度的平均值； （2）汗水 速度; （3）热灵敏度的主观评级。次要假设：四边形的人将 平均远端皮肤温度和出汗率的变化百分比较小，并且会报告钝 与AB对照相比，热灵敏度的评级。 我们拟议的研究将确认我们在具有亚正常Tcore的SCI患者中的初步观察结果 以更确定的方式证明，通过将TCORE提高到正常，可以提高认知功能。 通过将TCORE提高约0.5°C，快速并急剧逆转认知功能的损害 安乐死价值，我们预计功能能力和独立性更大，增强了重新融合 尽管这些终点超出了当前提议的范围，但进入社会和改善的生活质量。