Are demographic factors, masticatory performance and structural brain signatures associated with cognitive impairment in older people? A pilot study of cross-sectional neuroimaging data

Background: The occurrence of cognitive impairment (CI) is expected to increase within an ageing population. CI is associated with tooth loss, which influences masticatory performance. A decrease in masticatory performance may cause functional and morphological changes in the brain. However, whether CI is associated with masticatory performance, demographics, and structural brain signatures has not been studied yet. Objectives: To assess the associations between CI on the one hand, and masticatory performance, demographic factors, and structural brain signatures (i.e. cortical volume and thickness) on the other hand. Methods: In total, 18 older adults with CI (mean ± SD age = 72.2 ± 9.5 years) and 68 older adults without CI (65.7 ± 7.5 years) were included in this study. Masticatory performance was quantified using a colour-changeable chewing gum. A Magnetic Resonance Imaging (MRI) scan was used to map structural brain signatures. To study our aim, a multivariate binary logistic regression analysis with backward selection was performed. Results: The cortical volume of the right entorhinal cortex was negatively associated with CI (p <.01). However, demographic factors, masticatory performance, and the other structural brain signatures under investigation were not associated with CI. Conclusion: A decrease in the volume of the right entorhinal cortex is associated with CI in older people.