Association Between Oral Function Limitation and Frailty-Related Functional Impairment in Older Koreans: An Analysis of KNHANES 2024

Background/Objectives: Oral function limitation (OFL) may be associated with functional decline in older adults, but evidence from nationally representative data remains limited. This study examined the association between OFL and frailty-related functional impairment among older Korean adults using data from the 2024 Korea National Health and Nutrition Examination Survey (KNHANES). Methods: This cross-sectional study included 1247 adults aged 65 years or older with complete data on chewing discomfort, speech discomfort, remaining natural teeth, Life Functioning-10 (LF-10), falls, and bedridden status. OFL was defined as the sum of chewing discomfort, speech discomfort, and having fewer than 20 remaining natural teeth, with scores ranging from 0 to 3. Outcomes were LF-10 score, falls during the past year, and bedridden status during the past month. Complex-sample linear and logistic regression analyses were performed with sequential adjustment for sociodemographic factors, health behaviors, chronic diseases, and oral health-related factors. Results: The weighted mean LF-10 score decreased stepwise as the OFL score increased, from 90.99 in the OFL = 0 group to 77.64 in the OFL = 3 group. In the fully adjusted model, higher OFL scores were significantly associated with lower LF-10 scores. Severe OFL was associated with a higher likelihood of bedridden status; participants with OFL = 3 had approximately five times the odds of being bedridden compared with those with OFL = 0. No consistent association was observed between OFL and falls. Conclusions: Higher OFL scores were associated with lower life functioning and a higher likelihood of bedridden status among older Korean adults. Simple OFL indicators may serve as oral health markers associated with current frailty-related functional impairment in community settings.