Moon Jangsup, Choi Kang Hyun, Park Jung Hyun, Song Tae Jin, Choi Yun Seo, Kim Ju Hee, Kim Hyeon Jin, Lee Hyang Woon
Department of Neurology, Ewha Womans University School of Medicine and Ewha Medical Research Institute, Seoul, Korea.
Department of Medical Science, Ewha Womans University School of Medicine and Ewha Medical Research Institute, Seoul, Korea.
J Clin Neurol. 2018 Jul;14(3):310-319. doi: 10.3988/jcn.2018.14.3.310. Epub 2018 Apr 27.
Obstructive sleep apnea (OSA) is associated with cerebral white-matter changes (WMC), but the underlying mechanisms are not completely understood. Our aim was to identify the cardiovascular autonomic characteristics during sleep that are associated with cerebral WMC in OSA patients.
We recruited subjects from our sleep-center database who underwent both polysomnography and brain MRI within a 1-year period. Sixty patients who had OSA with WMC (OSA+WMC), 44 patients who had OSA without WMC (OSA-WMC), and 31 control subjects who had neither OSA nor WMC were analyzed. Linear and nonlinear indices of heart-rate variability (HRV) were analyzed in each group according to different sleep stages and also over the entire sleeping period.
Among the nonlinear HRV indices, the Poincaré ratio (SD12) during the entire sleep period was significantly increased in the OSA+WMC group, even after age adjustment. Meanwhile, detrended fluctuation analysis 1 during non-rapid-eye-movement sleep tended to be lowest in the OSA+WMC group. These indices were altered regardless of the presence of hypertension or diabetes. In the subgroup analysis of middle-aged OSA patients, approximate entropy during rapid-eye-movement sleep was significantly lower in OSA+WMC patients than in OSA-WMC patients. Overall, the nonlinear HRV indices suggest that sympathetic activity was higher in the OSA+WMC group than in the OSA-WMC and control groups.
Our findings suggest that dysregulation of HRV, especially overactivation of sympathetic tone, could be a pathophysiologic mechanism underlying the development of WMC in OSA patients.
阻塞性睡眠呼吸暂停（OSA）与脑白质改变（WMC）相关，但其潜在机制尚未完全明确。我们的目的是确定OSA患者睡眠期间与脑WMC相关的心血管自主神经特征。
我们从睡眠中心数据库招募了在1年内接受多导睡眠图和脑部MRI检查的受试者。分析了60例患有WMC的OSA患者（OSA+WMC）、44例未患有WMC的OSA患者（OSA-WMC）和31例既无OSA也无WMC的对照受试者。根据不同睡眠阶段以及整个睡眠期，对每组的心率变异性（HRV）线性和非线性指标进行分析。
在非线性HRV指标中，即使经过年龄调整，OSA+WMC组在整个睡眠期的庞加莱比率（SD12）仍显著升高。同时，非快速眼动睡眠期间的去趋势波动分析1在OSA+WMC组中往往最低。无论是否存在高血压或糖尿病，这些指标都会改变。在中年OSA患者的亚组分析中，OSA+WMC患者快速眼动睡眠期间的近似熵显著低于OSA-WMC患者。总体而言，非线性HRV指标表明OSA+WMC组的交感神经活动高于OSA-WMC组和对照组。
我们的研究结果表明，HRV失调，尤其是交感神经张力过度激活，可能是OSA患者WMC发生的病理生理机制。
