Cognitive impairment and depressive symptoms lead to biases in self-evaluated masticatory performance among community-dwelling older Japanese adults: the Tsurugaya Project

Objective: This cross-sectional study aims to examine if cognitive impairment, depressive symptoms, and their combination are associated with biases between self-evaluated and measured masticatory performance in community-dwelling older Japanese adults. Methods: The sample constituted of 804 community-dwelling elderly Japanese individuals aged 70 years. Cognitive impairment and depressive symptoms were assessed using the Mini-Mental State Examination and Geriatric Depression Scale, respectively. Self-evaluated masticatory performance (SMP) was assessed for 10 food items. Measured masticatory performance (MMP) was assessed as the maximum occlusal force, which is a surrogate indicator. Multivariate logistic regression was applied to examine the associations of cognitive impairment, depressive symptoms, and their combination with the deviation between SMP and MMP, SMP overestimation, and SMP underestimation, with adjustment for age, sex, body mass index, smoking, alcohol consumption, duration of education, medical history, physical function, regular dental visits, and number of teeth. Results: Cognitive impairment was significantly associated with SMP overestimation (odds ratio [OR]: 2.37, 95% confidence interval [CI]: 1.25-4.50); in parallel, SMP underestimation was significantly associated with depressive symptoms (OR: 1.86, 95% CI: 1.14-3.04) and the presence of both cognitive impairment and depressive symptoms (OR: 2.77, 95% CI: 1.01-7.61). Conclusions: This cross-sectional study clarifies the gap between self-evaluated and measured masticatory performance in geriatric participants who have cognitive impairment or depressive symptoms. These biases must be taken into consideration when appraising self-evaluated masticatory performance or oral health status in geriatric patients with cognitive impairment or depressive symptoms. Clinical Significance: This study explores the biases in geriatric patients with cognitive impairment or symptoms of depression. It clarifies that participants with cognitive impairment tend to overestimate their self-evaluated masticatory performance. Conversely, the participants with depression symptoms tend to underestimate their self-evaluated masticatory performance.