Multidomain Assessment of the Association Between Oral and Cognitive Function in Community-Dwelling Older Adults: A...

Oral function is considered a potentially modifiable factor associated with cognitive decline; however, few studies have evaluated multiple domains of oral function to determine which measures are independently associated with mild cognitive impairment (MCI) in community-dwelling older adults.

This cross-sectional study included community-dwelling older adults aged ≥ 60 years in a rural city in Niigata Prefecture, Japan. Cognitive function was evaluated using the Japanese version of the Montreal Cognitive Assessment (MoCA-J), with scores < 25 indicating MCI. Six oral function measures, based on diagnostic criteria for oral hypofunction, were assessed: tongue coating index (TCI), oral moisture, masticatory function (a* value), swallowing function (Oral Frailty 5-item Checklist, OF-5), oral diadochokinesis (ODK) /ta/, and maximum tongue pressure. Correlation and logistic regression analyses were performed, and statistical significance was defined as p < 0.05.

Among 303 participants, 179 had MCI. In the fully adjusted model, ODK /ta/ (OR = 0.621, p = 0.012), maximum tongue pressure (OR = 0.959, p = 0.014), and masticatory function (OR = 0.945, p = 0.044) were independently and inversely associated with MCI. Oral moisture, TCI, and OF-5 were not significantly associated. ODK /ta/ showed the strongest correlation with MoCA-J scores (r = 0.302, p < 0.001).

ODK /ta/, maximum tongue pressure, and masticatory function were independently associated with MCI in community-dwelling older adults. Among these, ODK /ta/ showed the strongest correlation with MoCA-J scores (r = 0.302). These findings suggest that multidomain assessment of oral function may serve as a useful indicator for identifying older adults at risk of cognitive decline, warranting further longitudinal investigation.