Oral Frailty and Social Frailty Among Older Japanese

To examine the association between oral frailty (OF) and social frailty (SF) among independent community-dwelling older adults in Japan.

A cross-sectional study was conducted using data from the 2022 wave of the Japan Gerontological Evaluation Study (JAGES) including 19,319 functionally independent older adults aged ≥ 65 years. Oral frailty was used as an exposure variable in four ways: (1) a categorical variable (robust = 0, pre-frail = 1, frail ≥ 2), (2) count score (sum of 5 OF components), (3) individual OF components and (4) a combined variable for the four oral functions. SF was measured using the 5-item index (SF-5; robust = 0, pre-frail = 1, frail ≥ 2). Missing data were handled via multiple imputation. Ordered logistic regression models were used after adjusting for sociodemographic and health-related covariates.

Participants were 48.4% males and aged 65-104 years. SF prevalence was 28.3% (n = 5466). In the adjusted models, oral frail individuals had higher odds of being socially frail (OR 1.35; 95% CI 1.26-1.45) than the robust group and the highest oral frailty score (score 5) showed the highest odds (OR 2.53; 95% CI 1.50-4.27) for SF. In addition, among OF components, dry mouth had the strongest association (OR 1.29; 95% CI 1.20-1.38), and those with four diminished oral functions were more likely to be socially frail (OR 2.42; 95% CI 1.53-3.82). Overall, a clear gradient-like pattern was observed with more oral frailty linked to higher odds of social frailty.

OF and its components were associated with SF among older adults in Japan. These findings might suggest the need for integrated screening and preventive strategies to mitigate social vulnerability linked to oral functional decline.