Department of Dentistry, School of Dentistry, National Yang-Ming University, Taiwan, ROC.
Institute of Oral Biology, School of Dentistry, National Yang-Ming University, Taiwan, ROC; Division of Family Dentistry, Department of Stomatology, Taipei Veterans General Hospital, Taiwan, ROC.
Exp Gerontol. 2019 Jan;115:1-8. doi: 10.1016/j.exger.2018.11.007. Epub 2018 Nov 8.
Swallowing is a complex movement consisting of the sequential and orderly activation of the swallowing muscles. Neuroimaging evidence has revealed a complex cortical and subcortical representation of voluntary swallowing. The repetitive saliva swallowing test (RSST) is a convenient and simple method for assessing swallowing performance in older people. It remains unclear whether individual differences in swallowing performance are associated with variations in structural brain signatures. We aimed to investigate the association between swallowing efficiency (SWE, measured by the RSST) and gray matter volume (GMV) in healthy older adults. Forty healthy older adults (52-82 years old, 28 female) underwent T1-weighted magnetic resonance imaging (MRI) and clinical assessments of SWE, stimulated/unstimulated salivary flow rate, masticatory cycle, and walking speed. GMV was quantified using a voxel-based morphometry (VBM) approach based on the MRI data. SWE was significantly negatively correlated with age. The association between SWE and hand grip strength, but not the other clinical metrics, was statistically significant. The GMV of the left posterior cerebellum (from cerebellum crus to lobule VIII) was significantly positively correlated with SWE, as evidenced by the results of whole-brain and cerebellum-specific VBM analyses. SWE was significantly positively correlated with the cerebellar volume in the region-of-interest analyses based on automated segmentation. In healthy older adults, swallowing efficiency was positively correlated with cerebellar GMV. The findings suggested that in older people, structural variations of the brain may play a key role in individual differences in swallowing performance.
吞咽是一个复杂的运动，由吞咽肌肉的顺序和有序激活组成。神经影像学证据揭示了自愿吞咽的复杂皮质和皮质下表现。重复唾液吞咽测试（RSST）是评估老年人吞咽功能的一种方便、简单的方法。目前尚不清楚吞咽功能的个体差异是否与结构脑特征的变化有关。我们旨在研究健康老年人中吞咽效率（通过 RSST 测量）与灰质体积（GMV）之间的关系。40 名健康老年人（52-82 岁，28 名女性）接受了 T1 加权磁共振成像（MRI）和吞咽效率、刺激/非刺激唾液流率、咀嚼周期和步行速度的临床评估。使用基于 MRI 数据的基于体素形态计量学（VBM）方法来量化 GMV。吞咽效率与年龄呈显著负相关。吞咽效率与握力之间的关联，而不是与其他临床指标之间的关联具有统计学意义。左小脑后部（从小脑脚到小脑小叶 VIII）的 GMV 与吞咽效率呈显著正相关，这是通过全脑和小脑特异性 VBM 分析的结果证明的。基于自动分割的感兴趣区分析显示，吞咽效率与小脑体积呈显著正相关。在健康老年人中，吞咽效率与小脑 GMV 呈正相关。这些发现表明，在老年人中，大脑的结构变化可能在吞咽功能的个体差异中起着关键作用。
