Multidimensional oral health and frailty in older adults: A sex-stratified cross-sectional study

Background: Frailty in older adults is a critical public health concern associated with increased morbidity, disability, and healthcare utilization. Although systemic health and socioeconomic factors are well-established determinants of frailty, the multidimensional nature of oral health has received relatively limited attention in previous research. The aim of this study was to examine the associations between general characteristics, health-related factors, oral health factors, and frailty among community-dwelling older adults, and to identify sex differences in frailty. Methods: This cross-sectional study used data from the 2022 Korean Longitudinal Study of Aging (KLoSA) and included 3,729 individuals aged 65 years and older. Frailty was categorized as robust, pre-frail, or frail using the Frailty Instrument developed for older Korean adults. General characteristics, health-related factors, and oral health-related factors (structural, behavioral, and subjective) were assessed through structured questionnaires. Hierarchical logistic regression analysis was performed in three steps to identify factors associated with frailty. Results: Of the participants, 16.0% were frail and 84.0% were non-frail (31.5% pre-frail and 52.5% robust). Sex-stratified analyses also showed that structural oral health factors were most strongly associated with frailty in both sexes. Edentulous status without denture use was associated with the highest odds of frailty in both women (OR = 3.76, 95% CI = 3.72–3.80) and men (OR = 2.95, 95% CI = 2.91–2.98). In contrast, sex differences were observed for some subjective oral health factors: tooth sensitivity was associated with higher odds of frailty in women (OR = 1.82, 95% CI = 1.80–1.84) but lower odds in men (OR = 0.85, 95% CI = 0.84–0.86). Conclusions: Oral health conditions, including untreated tooth loss, difficulty in chewing or swallowing, and oral pain, were significantly associated with frailty. These findings suggest that oral health may be an important factor to consider in relation to frailty among community-dwelling older adults.