Chen Hsiu-Ling, Huang Chih-Cheng, Lin Hsin-Ching, Lu Cheng-Hsien, Chen Pei-Chin, Chou Kun-Hsien, Su Mao-Chang, Friedman Michael, Lin Ching-Po, Lin Wei-Che
Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan.
J Clin Sleep Med. 2020 Feb 15;16(2):293-302. doi: 10.5664/jcsm.8186. Epub 2020 Jan 13.
Autonomic impairment and white matter (WM) alterations have been noted as effects of obstructive sleep apnea (OSA). This study sought to evaluate the change of WM integrity in patients with OSA using diffusion tensor imaging (DTI) and to determine its relationship with autonomic impairment.
A total of 30 patients with moderate and severe OSA and 19 healthy volunteers were recruited. A cardiovascular autonomic survey was performed and the baroreflex sensitivity (BRS) for each participant was derived from changes in heart rate and blood pressure during the early part of phase II of the Valsalva maneuver. DTI-related indices were derived from DTI. The fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) maps were compared using voxel-based statistics to determine differences between the patients with OSA and the healthy controls. The correlations among DTI indices, clinical severity, and autonomic parameters were investigated.
The BRS values were significantly worse in the OSA group than in the control patients. An exploratory group-wise comparison between the two groups revealed that the patients with OSA exhibited low FA, increased MD, AD, and RD in several brain locations. The declined DTI indices in autonomic-related areas were significantly correlated with increased clinical disease severity and baroreflex impairment.
OSA alters WM integrity in the cingulum and temporal lobe, and this impairment might play some role in autonomic dysfunction. The possible interaction between autonomic dysfunction and central nervous system microstructural alterations may represent variant hypoxic patterns, sympathetic activation, and their consequent processes in OSA.
自主神经功能障碍和白质（WM）改变已被认为是阻塞性睡眠呼吸暂停（OSA）的影响因素。本研究旨在使用扩散张量成像（DTI）评估OSA患者WM完整性的变化，并确定其与自主神经功能障碍的关系。
共招募了30例中重度OSA患者和19名健康志愿者。进行了心血管自主神经功能检查，并根据瓦尔萨尔瓦动作第二阶段早期心率和血压的变化得出每位参与者的压力反射敏感性（BRS）。DTI相关指标来自DTI。使用基于体素的统计方法比较分数各向异性（FA）、平均扩散率（MD）、轴向扩散率（AD）和径向扩散率（RD）图，以确定OSA患者与健康对照之间的差异。研究了DTI指标、临床严重程度和自主神经参数之间的相关性。
OSA组的BRS值明显低于对照组患者。两组之间的探索性组间比较显示，OSA患者在几个脑区表现出低FA、增加的MD、AD和RD。自主神经相关区域DTI指标的下降与临床疾病严重程度增加和压力反射受损显著相关。
OSA会改变扣带和颞叶的WM完整性，这种损害可能在自主神经功能障碍中起一定作用。自主神经功能障碍与中枢神经系统微观结构改变之间的可能相互作用可能代表了OSA中不同的缺氧模式、交感神经激活及其后续过程。
