Swallowing performance in older adults: Associated cognitive, neuroanatomical and demographic factors

Background: Swallowing problems are frequently seen in older adults, especially in individuals with cognitive impairment (CI). The brain plays a crucial role in both cognition and swallowing. Using magnetic resonance imaging (MRI) data, researchers identified regions associated with swallowing. However, it is not yet fully elucidated which factors influence the swallowing performance in older adults. Objectives: The current study investigated which factors, such as cognitive function, neuroanatomical factors (e.g., the cortical thickness and volume of specific brain regions) and demographical factors are associated with swallowing performance in older adults. Secondly, it was investigated whether there is a difference in neuroanatomical factors between individuals with and without CI. Research Design and Methods: In total, 15 CI individuals (73.1 +/- 9.1 years; 46.7% male) and 48 non-CI controls (69.0 +/- 5.1 years; 29.2% male) were included. The repetitive saliva swallowing test (RSST) was performed, and an MRI scan was acquired from the participants. Results: Multivariate linear regression analysis showed that the cortical thickness of the right supramarginal gyrus and female gender were positively associated, and a higher age was negatively associated with the RSST in older adults (p < .05). CI was not significantly associated with swallowing performance. Furthermore, it was found that the cortical volume differs more frequently between CI and non-CI than the cortical thickness. Conclusion: A thinner cortex of the right supramarginal gyrus and being an older female are associated with poorer swallowing performance. Secondly, cortical volume was more often found to differ between CI and non-CI individuals than cortical thickness.