Department of Neurology, Miller School of Medicine, University of Miami, 1120 NW 14th Street, Suite 1350, Miami, FL 33136, USA.
Sleep Breath. 2013 May;17(2):723-6. doi: 10.1007/s11325-012-0748-5. Epub 2012 Jul 7.
The aim of our study is to determine the association between the pulsatility index (PI), a surrogate of cerebral small vessel disease and sleep-disordered breathing (SDB).
We conducted a transcranial Doppler ultrasound (TCD) study of 19 consecutive patients free of stroke and cardiovascular disease, referred for the evaluation of SDB. TCD was performed by a certified technologist. Subsequent polysomnography was performed according to the practice parameters of the American Academy of Sleep Medicine. We evaluated the association between the apnea-hypopnea index (AHI), the oxygen nadir, the blood flow velocities, and the Gosling PI, for the middle cerebral artery. We performed Spearman's rank correlation and nonparametric regression to evaluate the relationship between AHI, oxygen levels, and the PI.
Median age was 48 years (range 37-83), with 52 % male sex (n = 10), and median BMI of 29.9 (range 25-40.4). The median AHI was 16.4 (0.2-69). The median PI was 0.97 (0.72-1.89) cm/s. The PI correlated with the AHI (rho = 0.44; p = 0.004) and with age (rho = 0.57; p = 0.001). Nonparametric regression adjusting for age showed a positive association between the AHI and the PI (standardized estimate = 0.88; p = 0.002). There was no relation between the oxygen nadir and the PI.
We observed increased PI in patients with SDB during wakefulness. The PI could potentially be an estimate of cerebral small vessel disease in patients with SDB and hence allow evaluating cerebral hemodynamics during wakefulness with a clinically relevant device.
我们的研究旨在确定搏动指数（PI），一种脑小血管疾病的替代指标，与睡眠呼吸障碍（SDB）之间的关联。
我们对 19 例无中风和心血管疾病的连续患者进行了经颅多普勒超声（TCD）研究，这些患者因 SDB 评估而就诊。TCD 由认证技术员进行。随后根据美国睡眠医学学会的实践参数进行多导睡眠图检查。我们评估了呼吸暂停-低通气指数（AHI）、氧饱和度最低点、血流速度与大脑中动脉的 Gosling PI 之间的关联。我们进行 Spearman 等级相关和非参数回归分析，以评估 AHI、氧水平和 PI 之间的关系。
中位年龄为 48 岁（范围 37-83），52%为男性（n=10），中位 BMI 为 29.9（范围 25-40.4）。中位 AHI 为 16.4（0.2-69）。中位 PI 为 0.97（0.72-1.89）cm/s。PI 与 AHI 相关（rho=0.44；p=0.004），与年龄相关（rho=0.57；p=0.001）。调整年龄的非参数回归显示，AHI 与 PI 呈正相关（标准化估计值=0.88；p=0.002）。PI 与氧饱和度最低点之间无相关性。
我们观察到在清醒状态下 SDB 患者的 PI 增加。PI 可能是 SDB 患者脑小血管疾病的估计值，因此可以使用临床相关设备评估清醒时的脑血流动力学。
