Oral hypofunction and its association with frailty in community-dwelling older people.

AIM: This large epidemiological survey of older people examined oral hypofunction and the relationship between oral hypofunction and frailty. METHODS: Participants were community-dwelling adults aged 65-85 years in Japan. The oral function evaluation included seven items (oral hygiene, oral dryness, occlusal force, tongue-lip motor function, tongue pressure, masticatory function and swallowing function), and oral hypofunction was defined as having abnormalities in at least three of these items. The frailty status was classified into three categories (robust, pre-frail and frail) according to the total Kihon Checklist score. We analyzed 978 subjects with complete data. The relationship between oral function and frailty status was analyzed using multivariate multinomial logistic regression analyses. RESULTS: Approximately 60% of the older adults had oral hypofunction. The multivariate odds ratios (ORs) for a pre-frail or frail status were significantly higher for older people with reduced occlusal force, reduced tongue-lip motor function and deteriorated swallowing function than in those without deterioration of those items. Of the oral function items, swallowing function was most strongly associated with the frailty status, and the ORs (95% confidence interval [CI]) for deteriorated swallowing function in pre-frail and frail patients were 6.4 (3.9-10.8) and 10.2 (5.4-19.1), respectively. Those with oral hypofunction had significantly higher adjusted ORs for pre-frail (OR 1.4, 95% CI 1.1-2.0) and frail (OR 2.1, 95% CI 1.2-3.5) statuses. CONCLUSION: Many community-dwelling older people have reduced oral function or oral hypofunction, which is significantly associated with frailty in older people. Geriatr Gerontol Int 2020; 20: 917-926.