背景:步态障碍在患有血管疾病的老年人中很常见。然而,颈动脉粥样硬化如何影响步态仍然知之甚少。目的是研究颈动脉内膜中层厚度与特定步态表现之间的关联,并探索大脑结构在介导这些关联中的潜在作用。
方法:对台州影像学研究的数据进行横断面分析,包括707名同时接受步态和颈动脉超声检查的患者。步态评估包括定时上行测试,Tinetti测试,和使用可穿戴设备的定量步态评估。用因子分析将定量参数归纳为独立的步态域。磁共振图像是在3.0特斯拉扫描仪上获得的,以及与运动功能相关的15个大脑区域的体积(初级运动,感觉运动),视觉空间注意力(后顶叶下小叶,后顶叶小叶),执行控制功能(背外侧前额叶皮层,前扣带),记忆(海马,内嗅皮层),运动意象(precuneus,海马旁,后扣带皮质),和平衡(基底神经节:苍白球,壳核,尾状,丘脑)是使用FreeSurfer和Desikan-Killiany图集计算的。以颈动脉内膜-中膜厚度为预测因子,运动相关脑区为中介因子进行中介分析。
结果:颈动脉内膜-中膜厚度被发现与定时上升和运动性能(β=0.129,p=0.010)以及与步速相关的步态性能(β=-0.213,p<0.001)和对称性(β=0.096,p=0.045)。此外,步态表现与负责运动的与运动相关的大脑区域相关,视觉空间注意力,执行控制,记忆,和平衡(所有FDR<0.05)。值得注意的是,重要区域根据测量的步态结果而有所不同。主电机(41.9%),感觉运动(29.3%),视觉空间注意力(后顶叶下小叶,后顶叶上小叶)(13.8%),内嗅皮层(36.4%),和运动意象(precuneus,海马旁,后扣带皮质)(27.3%)介导了颈动脉内膜中膜厚度增加与Timed-Up-and-Go表现较差之间的关联。对于pace域,主电机(37.5%),感觉运动(25.8%),视觉空间注意力(12.3%),内嗅皮层(20.7%),运动图像(24.9%),和平衡(基底神经节:苍白球,壳核,尾状,丘脑)(11.6%)充当介质。
结论:颈动脉内中膜厚度与步态表现有关,与移动性相关的脑容量调节了这些关联。此外,在不同的步态域中,调节运动的脑区的分布是不同的。我们的研究为探索老年人步态障碍的潜在机制增加了价值。
BACKGROUND: Gait disturbance is common in older adults with vascular diseases. However, how carotid atherosclerosis affects gait remains poorly understood. The objectives were to investigate the associations between carotid intima-media thickness and specific gait performances and explore the potential role of brain structure in mediating these associations.
METHODS: A cross-sectional analysis of data from the Taizhou Imaging Study was conducted, including 707 individuals who underwent both gait and carotid ultrasound examinations. Gait assessments include the Timed-Up-and-Go test, the Tinetti test, and quantitative gait assessment using a wearable device. Quantitative parameters were summarized into independent gait domains with factor analysis. Magnetic resonance images were obtained on a 3.0-Tesla scanner, and the volumes of fifteen brain regions related to motor function (primary motor, sensorimotor), visuospatial attention (inferior posterior parietal lobules, superior posterior parietal lobules), executive control function (dorsolateral prefrontal cortex, anterior cingulate), memory (hippocampus, entorhinal cortex), motor imagery (precuneus, parahippocampus, posterior cingulated cortex), and balance (basal ganglia: pallidum, putamen, caudate, thalamus) were computed using FreeSurfer and the Desikan-Killiany atlas. Mediation analysis was conducted with carotid intima-media thickness as the predictor and mobility-related brain regions as mediators.
RESULTS: Carotid intima-media thickness was found to be associated with the Timed-Up-and-Go performance (β = 0.129, p = 0.010) as well as gait performances related to pace (β=-0.213, p < 0.001) and symmetry (β = 0.096, p = 0.045). Besides, gait performances were correlated with mobility-related brain regions responsible for motor, visuospatial attention, executive control, memory, and balance (all FDR < 0.05). Notably, significant regions differed depending on the gait outcomes measured. The primary motor (41.9%), sensorimotor (29.3%), visuospatial attention (inferior posterior parietal lobules, superior posterior parietal lobules) (13.8%), entorhinal cortex (36.4%), and motor imagery (precuneus, parahippocampus, posterior cingulated cortex) (27.3%) mediated the association between increased carotid intima-media thickness and poorer Timed-Up-and-Go performance. For the pace domain, the primary motor (37.5%), sensorimotor (25.8%), visuospatial attention (12.3%), entorhinal cortex (20.7%), motor imagery (24.9%), and balance (basal ganglia: pallidum, putamen, caudate, thalamus) (11.6%) acted as mediators.
CONCLUSIONS: Carotid intima-media thickness is associated with gait performances, and mobility-related brain volume mediates these associations. Moreover, the distribution of brain regions regulating mobility varies in the different gait domains. Our study adds value in exploring the underlying mechanisms of gait disturbance in the aging population.