Jensen-Dahm Christina, Waldemar Gunhild, Staehelin Jensen Troels, Malmqvist Lasse, Moeller Michelle Mai, Andersen Birgitte Bo, Høgh Peter, Ballegaard Martin
Danish Dementia Research Centre, Department of Neurology, Rigshospitalet, University of Copenhagen, Denmark.
Danish Pain Research Center, Department of Neurology, Aarhus University Hospital, Denmark.
J Alzheimers Dis. 2015;47(3):681-9. doi: 10.3233/JAD-150169.
Autonomic function has received little attention in Alzheimer's disease (AD). AD pathology has an impact on brain regions which are important for central autonomic control, but it is unclear if AD is associated with disturbance of autonomic function.
To investigate autonomic function using standardized techniques in patients with AD and healthy age-matched controls.
Thirty-three patients with mild to moderate AD and 30 age- and gender-matched healthy controls, without symptoms of autonomic dysfunction, underwent standardized autonomic testing with deep breathing, Valsalva maneuver, head-up tilt, and isometric handgrip test. Brachial pressure curve and electrocardiogram were recorded for off-line analysis of blood pressure and beat-to-beat heart rate (HR).
AD patients had impaired blood pressure responses to Vasalva maneuver (p < 0.0001) and HR response to isometric contraction (p = 0.0001). A modified composite autonomic scoring scale showed greater degree of autonomic impairment in patients compared to controls (patient: 2.1 ± 1.6; controls: 0.9 ± 1.1, p = 0.001). HR response to deep breathing and Valsalva ratio were similar in the two groups.
We identified autonomic impairment ranging from mild to severe in patients with mild to moderate AD, who did not report autonomic symptoms. Autonomic impairment was mainly related to impairment of sympathetic function and evident by impaired blood pressure response to the Vasalva maneuver. The clinical implications of this finding are that AD may be associated with autonomic disturbances, but patients with AD may rarely report symptoms of autonomic dysfunction. Future research should systematically evaluate symptoms of autonomic function and characterize risk factors associated with autonomic dysfunction.
自主神经功能在阿尔茨海默病（AD）中很少受到关注。AD病理会影响对中枢自主神经控制很重要的脑区，但目前尚不清楚AD是否与自主神经功能紊乱有关。
采用标准化技术研究AD患者和年龄匹配的健康对照者的自主神经功能。
33例轻度至中度AD患者和30例年龄及性别匹配、无自主神经功能障碍症状的健康对照者，接受了包括深呼吸、瓦尔萨尔瓦动作、头高位倾斜和等长握力试验在内的标准化自主神经测试。记录肱动脉压力曲线和心电图，用于离线分析血压和逐搏心率（HR）。
AD患者对瓦尔萨尔瓦动作的血压反应受损（p<0.0001），对等长收缩的HR反应受损（p=0.0001）。改良的综合自主神经评分量表显示，与对照组相比，患者的自主神经损伤程度更高（患者：2.1±1.6；对照组：0.9±1.1，p=0.001）。两组对深呼吸的HR反应和瓦尔萨尔瓦比率相似。
我们在未报告自主神经症状的轻度至中度AD患者中发现了从轻度到重度的自主神经损伤。自主神经损伤主要与交感神经功能损伤有关，表现为对瓦尔萨尔瓦动作的血压反应受损。这一发现的临床意义在于，AD可能与自主神经紊乱有关，但AD患者可能很少报告自主神经功能障碍症状。未来的研究应系统地评估自主神经功能症状，并确定与自主神经功能障碍相关的危险因素。
