Background: It has not been clarified whether physical frailty symptoms predict social. frailty. The purpose of this study was to elucidate the effect of physical frailty on social frailty, and to determine which domains of physical frailty predict the development of social frailty. Methods: We employed a two-year prospective cohort study. A total of 342 socially robust community-dwelling older adults were recruited. We used a modified social frailty screening index consisting of four social domains including financial difficulties, living alone, social activity, and contact with neighbors. Physical frailty status was also assessed at baseline. At the two-year follow-up, we assessed the development of social frailty. Social status was assessed using four social subdomains for the primary analysis. Social status was assessed using the two social subdomains of social activity and contact with neighbors, which would be affected by the physical frailty component, for the secondary analysis. The risk ratios (RR) of physical frailty for the development of social frailty were estimated. Results: Although physical frailty symptoms were not a significant risk factor for future development of social frailty as assessed by four social subdomains (adjusted RR 1.39, 95% CI 0.95–2.15), it became significant when development of social frailty was assessed by the two social subdomains (adjusted RR 1.78, 95% CI 1.10–2.88). An analysis using the physical frailty subdomain showed that slow gait speed (adjusted RR 3.41, 95% CI 1.10–10.53) and weakness (adjusted RR 1.06, 95% CI 1.01–1.12) were independent risk factors for development of social frailty as assessed by two social subdomains. Conclusions: Physical frailty symptoms predict the development of social frailty. Among physical frailty subdomains, gait speed and muscle strength are critical independent risk factors for future decline in the social aspect. The prevention of physical frailty, especially by maintaining gait ability and muscle strength, may be effective for avoiding social frailty.

This cross-sectional study aimed to demonstrate the association between physical frailty subdomains and oral frailty. This study involved community-dwelling older adults (aged ≥65 years). Physical frailty was assessed with the Japanese version of the Cardiovascular Health Study criteria. Oral frailty was defined as limitations in at least three of six domains. Logistic regression analysis was used to analyze the association between physical frailty risk and oral frailty. In addition, we examined the association between physical frailty subdomains (gait speed, grip strength, exhaustion, low physical activity, and weight loss) and oral frailty. A total of 380 participants were recruited for this study. Overall, 18% and 14% of the participants were at risk of physical frailty and had oral frailty, respectively. Physical frailty risk (odds ratio (OR) = 2.40, 95% confidence interval (CI): 1.22–4.75, p = 0.012) was associated with oral frailty in multivariate analysis. In secondary analysis, among physical frailty subdomains, gait speed (OR = 0.85, 95% CI: 0.73–0.97, p = 0.019) was associated with oral frailty. The present findings suggest that physical frailty is closely related to oral frailty. Among physical frailty subdomains, decreased gait speed in particular is an important indicator related to the development of oral frailty.

It is often assumed that oral hypofunction is associated with social withdrawal in older adults because decreased motor function is related to decreased oral function. However, few studies have examined the relationship between social withdrawal in older adults and oral function. This longitudinal study aimed to clarify the relationship between changes in the level of social withdrawal and oral function in independent older adults. Participants were 427 older adults aged 65 years or older who took part in a self-administered questionnaire from 2016 to 2017 (baseline), and again two years later (follow-up). At baseline, 17 items related to oral function and confounding factors related to withdrawal, physical condition, physical function, and cognitive function were evaluated. A Cox proportional hazard model was used to examine the oral functions that negatively impact social withdrawal. The following factors were significantly associated with the worsening of social withdrawal: the number of remaining teeth, gingival condition, occlusal force, masticatory efficiency, and items related to swallowing and dry mouth. Older adults with cognitive issues who walk slowly and have a weak knee extension muscle were also significantly more likely to have oral frailty. Those who were found to have oral frailty at baseline were 1.8 times more likely to develop withdrawal compared to those with robust oral function. The results indicated that the worsening of withdrawal was associated with oral hypofunction at baseline. Since oral hypofunction was associated with the worsening of social withdrawal in older adults, it is important to maintain older adults’ oral function.

Objectives: Recently, isotemporal substitution has been developed to substitute activity time for an equivalent amount of another activity. This study employed this method to demonstrate the effects of replacing sedentary behavior (SB) time with an equivalent amount of light-intensity physical activity (LPA) and moderate-to-vigorous intensity physical activity (MVPA) on the risk for different severities of frailty. Methods: A total of 886 older adults (average age 73.6 years, female 70%) participated in this cross-sectional study. Frailty status was assessed according to the cardiovascular health study criteria. Main outcome measures: Wrist-worn accelerometers were used to measure SB, LPA, and MVPA. Isotemporal substitution models were applied to show the estimated effects of substituting 30 min of SB with an equal amount of time spent in LPA or MVPA on the risk for pre-frailty and frailty. Results: The physical activity level and SB were not associated with the incidence of pre-frailty. However, a 16% (OR: 0.84; 95% CI: 0.78–0.90) and 42% (OR: 0.58; 95% CI: 0.37–0.92) decrease in frailty risk was noted when SB was substituted with LPA and MVPA, respectively, in the crude model. In the adjusted model, the significant effect was sustained for LPA (OR: 0.86; 95% CI: 0.80–0.92) but not for MVPA (OR: 0.74; 95% CI: 0.47–1.17). Conclusions: This study indicates that replacing 30 min of SB with an equivalent amount of LPA decreases the risk for frailty in older adults. Moreover, increasing LPA seems more feasible than increasing MVPA in older adults, with substantial benefit.

To develop effective nutritional interventions for preventing frailty, the specific problems associated with the dietary habits of individuals based on sex differences must be identified. The purpose of this study was to evaluate the association between dietary habits and frailty in rural Japanese community-dwelling older adults. We recruited 800 participants, aged 65 and older, who underwent a comprehensive health examination between November 2015 and December 2017. Dietary habits were assessed by a brief self-administered dietary history questionnaire. Frailty was determined using either the Kihon Checklist (KCL) or the Japanese version of the Cardiovascular Health Study (J-CHS). The percentage of frail older adults was 8.4% according to KCL and 4.0% according to J-CHS. Various kinds of nutrient intakes, including three major nutrients, minerals, and vitamins in frail men, according to KCL, were the lowest. By contrast, there were no differences in nutrient intake between the robust, prefrail, and frail female groups according to KCL. We found significant associations of the intakes of soluble dietary fiber, potassium, folate, and vitamin C with a frail status in men (p = 0.035, 0.023. 0.012, and 0.007, respectively), and an association of the intake of vitamin C with a frail status in women (p = 0.027) according to J-CHS. Attention should be paid to the diagnostic criteria of frailty and to sex differences, when nutritional interventions for the prevention of frailty are planned.