Artificial intelligence detection of cognitive impairment in older adults during walking.

INTRODUCTION: To detect early cognitive impairment in community-dwelling older adults, this study explored the viability of artificial intelligence (AI)-assisted linear acceleration and angular velocity analysis during walking. METHODS: This cross-sectional study included 879 participants without dementia (female, 60.6%; mean age, 73.5 years) from the 2011 Comprehensive Gerontology Survey. Sensors attached to the pelvis and left ankle recorded the triaxial linear acceleration and angular velocity while the participants walked at a comfortable speed. Cognitive impairment was determined using Mini-Mental State Examination scores. Deep learning models were used to discern the linear acceleration and angular velocity data of 12,302 walking strides. RESULTS: The models' average sensitivity, specificity, and area under the curve were 0.961, 0.643, and 0.833, respectively, across 30 testing datasets. DISCUSSION: AI-enabled gait analysis can be used to detect signs of cognitive impairment. Integrating this AI model into smartphones may help detect dementia early, facilitating better prevention. Highlights: Artificial intelligence (AI)-enabled gait analysis can be used to detect the early signs of cognitive decline.This AI model was constructed using data from a community-dwelling cohort.AI-assisted linear acceleration and angular velocity analysis during gait was used.The model may help in early detection of dementia.

Developing a brief older adults' physical activity questionnaire.

AIM: This study aimed to develop and evaluate the Brief Older Adults' Physical Activity Questionnaire (BOPAQ), which was designed to quickly assess moderate-to-vigorous physical activity (MVPA) in community-dwelling older adults. METHODS: We used a cross-sectional study design involving 165 older participants. The BOPAQ calculated weekly MVPA duration based on two questions regarding the number of days per week engaged in MVPA and the daily duration of activity. Validity was assessed by correlating the MVPA durations derived from the BOPAQ with those obtained from the ActiGraph and International Physical Activity Questionnaire short form. Reliability was evaluated using the intraclass correlation coefficient, and measurement errors were analyzed using Bland-Altman plots. RESULTS: The BOPAQ reasonably correlated with accelerometer-based MVPA (rho = 0.297) and showed good test-retest reliability (intraclass correlation coefficient of 0.78, 95% CI 0.64-0.87). In contrast, the correlation between the International Physical Activity Questionnaire short form and accelerometer-based MVPA was poor (rho = 0.139). The cut-off value for the BOPAQ was set to identify participants engaging in <150 min of objectively measured physical activity per week, corresponding to the 150-min threshold. However, the area under the curve in the receiver operating characteristic analyses was not significantly high (0.601, 95% CI 0.514-0.688). The Bland-Altman plots showed an underestimation bias of 51.72 min/week (95% CI 1.61-101.84) and showed heteroscedasticity. CONCLUSION: Despite some measurement errors, the BOPAQ is an available tool for assessing MVPA in community-dwelling older adults. Geriatr Gerontol Int 2024; ••: ••-••.

Japan's cancer survivorship guidelines for exercise and physical activity.

OBJECTIVE: This research aimed to establish the inaugural evidence-based cancer survivorship guidelines for Japan, with a particular focus on exercise and physical activity, in order to enhance health outcomes for cancer survivors. METHODS: A panel of experts, including oncologists, physicians, exercise scientists, epidemiologists and patient advocates, utilized a modified Delphi process and systematic reviews to establish consensus on exercise recommendations for cancer survivors. The panel focused on setting the objectives of the Clinical Practice Guidelines and addressing crucial clinical issues in Japan. Recommendations were formulated based on the strength and certainty of evidence, the benefit-harm balance and patient values and preferences. RESULTS: The panel formulated exercise recommendations for cancer survivors of two age groups: 18-64 years and ≥65 years. The recommendations for both age groups are consistent, emphasizing the importance of regular exercise and physical activity tailored to individual capabilities and health conditions. The guidelines underline the benefits of exercise in improving the overall health and quality of life of cancer survivors. This consensus on exercise recommendations marks a significant step in the development of comprehensive cancer survivorship guidelines in Japan, with potential implications for improving clinical outcomes and advancing research in cancer survivorship. CONCLUSIONS: These guidelines will serve as a critical resource for cancer survivors, highlighting exercise as a key component of survivorship care, and for clinicians, in recommending appropriate physical activities to improve survivor health and well-being.

Association between phase angle and inflammatory blood biomarkers in community-dwelling older adults: Itabashi Longitudinal Study on Aging.

BACKGROUND & AIM: Bioelectrical impedance analysis-derived phase angle (PhA) reflects the disruption of the cell membrane and intra- and extracellular fluid imbalances caused by chronic inflammation. This study examined the association between PhA and inflammatory markers in community-dwelling older adults. METHODS: A sex-stratified logistic regression analysis was conducted, with elevated C-reactive protein (CRP; ≥3.0 mg/L) and interleukin-6 (IL-6; >4.0 pg/mL) levels as the outcomes and whole-body and local PhAs as the exposures. The same analysis was conducted with further stratification for age, overweight status, history of inflammation-related non-communicable diseases, and dietary inflammatory index. The ability to identify inflammation in whole-body and local PhAs was assessed using a receiver operating characteristic (ROC) curve. RESULTS: This study included 1664 participants (age: 76 [73-80] years; 855 women). In men, significant odds ratios (ORs) at the 95 % confidence interval (95 % CI) were observed for abnormal CRP and IL-6 levels for both whole-body and leg PhAs in the third quartile compared with the lowest quartile (OR [95 % CI] for abnormal CRP levels: 0.36 [0.18, 0.68] for whole-body PhA, 0.51 [0.27, 0.95] for leg PhA; OR [95 % CI] for abnormal IL-6 levels: 0.36 [0.15, 0.81] for whole-body PhA, 0.33 [0.12, 0.78] for leg PhA). The areas under the ROC curves (95 % CI) for identifying abnormal IL-6 were mild in men (0.62 [0.54, 0.70] for whole-body PhA and 0.62 [0.55, 0.70] for leg PhA). In men without a history of inflammation-related non-communicable diseases, it was 0.72 (0.59, 0.85) for whole-body PhA and 0.68 (0.54, 0.81) for leg PhA. In women, the PhA was not significantly associated with inflammatory markers. CONCLUSION: PhA is associated with inflammation in community-dwelling older men, but may need to be combined with other information to identify inflammation.

Association between the Intake/Type of Cheese and Cognitive Function in Community-Dwelling Older Women in Japan: A Cross-Sectional Cohort Study.

While many studies have described the association between cognitive decline and eating habits, little attention has been paid to its association with cheese intake. In this epidemiological study of 1035 community-dwelling women aged ≥ 65, we investigated the association between intake/type of cheese and cognitive function. The anthropometry, functional ability, and the frequency of food intake, including cheese, were assessed. The mini-mental state examination (MMSE) was used to assess cognitive function, and a score of 20-26 was operationally defined as mild cognitive decline. We found that the MMSE score was significantly different between the presence of cheese intake and not (cheese intake: 28.4 ± 1.9; non-cheese intake: 27.6 ± 2.4) and between those who consumed Camembert cheese and those who did not (Camembert cheese: 28.7 ± 1.4; others: 28.3 ± 2.0). After adjusting for confounders, multiple logistic regression identified four independent variables significantly associated with mild cognitive decline: Camembert cheese intake (odds ratio = 0.448, 95% confidence interval = 0.214-0.936), age, usual walking speed, and repetitive saliva swallowing test scores. Our results, while based on cross-sectional data from Japanese community-dwelling older women, identified the significant inverse association between Camembert cheese intake and mild cognitive decline.

Muscle Performance as a Predictor of Bone Health: Among Community-Dwelling Postmenopausal Japanese Women from Setagaya-Aoba Study.

Osteoporosis is a significant health concern for postmenopausal women, necessitating efficient screening methods for bone health. This study explores the potential of muscle function, assessed through the 30-s chair stand test (CS-30), as an indicator for low bone stiffness in this demographic, aiming to establish a practical threshold for large-scale fitness surveillance without the need for specialized tools. We analyzed data from 1055 community-dwelling postmenopausal Japanese women, aged 41-89 years, collected between 2016 and 2019. Participants underwent CS-30 to evaluate muscle function alongside quantitative ultrasound (QUS) measurements to assess bone stiffness. The cohort was divided into two groups for the development and validation of a cutoff point for low bone stiffness, defined as a QUS speed of sound less than 1487.3 m/s. The CS-30 cutoff was determined using receiver operating characteristic (ROC) curve analysis and validated through logistic regression, accounting for age, body mass index, and smoking status. Among 577 postmenopausal women, 16.0% exhibited low bone stiffness. In the development group (n = 382), ROC analysis identified a CS-30 cutoff of 25 repetitions for detecting low bone stiffness, with an area under the curve of 0.744 (P < 0.001). In the validation group (n = 195), participants performing ≥ 25 repetitions had a higher risk of low bone stiffness compared to those performing ≤ 24 repetitions. The CS-30 test is an effective preliminary screening tool for identifying postmenopausal women at risk of low bone stiffness, with a threshold of 25 repetitions. This method could facilitate early detection of individuals at higher osteoporosis risk, promoting timely intervention.

Association of the combination of social isolation and living alone with cognitive impairment in community-dwelling older adults: The IRIDE Cohort Study.

BACKGROUND: Living alone has been associated with cognitive impairment; however, findings have been inconsistent. Social isolation among older adults who live alone may contribute to cognitive impairment. This study was carried out to examine the association of social isolation and living alone with cognitive impairment in community-dwelling older adults. METHODS: In this cross-sectional study, data from the Integrated Research Initiative for Living Well with Dementia Cohort Study, which comprises pooled data from five community-based geriatric cohorts, was used. Social isolation was defined as infrequent interactions with others. Participants were categorized into four groups based on their social isolation and living alone statuses. Cognitive function was assessed using the Mini-Mental State Examination, with a score <24 indicating cognitive impairment. The association between social isolation combined with living alone and cognitive impairment was analyzed using logistic regression. RESULTS: Of the 4362 participants included in the analysis (mean age 75.6 years, 44.3 % male), 11 % had cognitive impairment. Regardless of living alone, social isolation was associated with cognitive impairment (no social isolation x not living alone: reference, social isolation x not living alone; odds ratio (OR): 1.74, 95 % confidence interval (CI): 1.29-2.33, social isolation x living alone; OR: 2.10, 95 % CI: 1.46-3.01). CONCLUSIONS: Social isolation is associated with cognitive impairment; however, living alone is not intrinsically associated with cognitive impairment in older adults. Healthcare providers must focus on social interactions to prevent cognitive impairment in older adults rather than simply focusing on living arrangements.

Knee Extensor Muscle Strength Associated with the Onset of Depression in Older Japanese Women: The Otassha Study.

We examined whether knee extensor muscle strength can predict the onset of depressive symptoms in older Japanese women living in Tokyo. A baseline comprehensive geriatric examination was conducted to evaluate isometric knee extensor muscle strength and depressive symptoms (using Geriatric Depression Scale [GDS]) in 2017-2019. A free of neurological disease participants received a series of follow-up examinations following an initial evaluation. A GDS score of ≥5 during follow-up marked the onset of depressive symptoms. A logistic regression model was established after adjustment of baseline GDS score for variables including age, body mass index, smoking, alcohol consumption, comorbidities, working status, hobbies, volunteering, years of education, and dietary variety. Of the 1845 recruited individuals, 1409 were eligible to be targeted for follow-up. Among them, 768 women provided two-year follow-up data and contributed the final analysis. After covariate adjustments, the odds ratios (95% confidence interval) for depressive symptoms were 0.68 (0.39, 1.20) and 0.48 (0.26, 0.91) for the middle and highest tertiles of muscle strength, respectively, using the lowest tertile as reference. A dose-response association between muscle strength and depression (p = 0.022) was identified. This study suggests an inverse dose-response relationship between knee extensor muscle strength and the onset of depressive symptoms in older Japanese women.

Association between Physical Activity and Quality of Life in Colorectal Cancer Patients with Postoperative Defecatory Dysfunction: A Preliminary Survey.

In this study, we aimed to explore the association between physical activity (PA) and quality of life (QoL) in colorectal cancer (CRC) patients with postoperative defecatory dysfunction. A survey using the European Organization for Research and Treatment of Cancer QLQ-30 and QLQ-29 was conducted among 62 adult outpatients with CRC at two cancer hospitals in Japan. PA and sedentary behavior were evaluated using the Global Physical Activity Questionnaire. Multiple regression analysis was performed, incorporating the QoL as the outcome, with the total PA and its three domains (occupational, transportation, and recreational) and sedentary time as exposures, while controlling for age, sex, and tumor location. The analyses revealed that patients engaged in PA ≥ 150 min/week (67.4 points; 95% confidence interval [CI]: 21.1, 113.8) and recreational PA ≥ 30 min/week (56.0 points; 95% CI: 2.3, 109.7) had significantly higher function scores. Conversely, sedentary time >8 h/day or occupational PA duration ≥30 min/week was associated with poor symptom and function scores. These findings highlight the importance of promoting recreational PA and reducing sedentary behavior to maintain and improve the QoL in CRC patients with defecatory dysfunction.

Serum albumin redox state as an indicator of dietary protein intake among community-dwelling older adults.

BACKGROUND AND AIMS: Serum markers capable of detecting mild levels of undernutrition, such as insufficient dietary protein intake (IDPI), have not been established among community-dwelling older adults. Although the serum albumin redox state, expressed as the ratio of reduced albumin (Alb) to total Alb (the reduced albumin ratio), has the potential to overcome this challenge, empirical epidemiological data are lacking. This study aimed to investigate the association between a serum reduced Alb ratio and dietary protein intake among community-dwelling older adults. METHODS: This study analyzed cross-sectional data from 1,005 community dwelling population (572 males and 433 females) aged 70-84 years who participated in the Itabashi Longitudinal Study on Aging. Exclusion criteria included participants with incomplete data, individuals with a history of kidney disease and high C-reactive protein (CRP) levels. The dietary protein intake was estimated using validated food frequency questionnaires. The IDPI was defined as not meeting the level recommended by the Dietary Reference Intakes for Japanese (Men ≥60 g/day, Women ≥50 g/day). RESULTS: IDPI was observed in 14.1% of the study population. Logistic regression analyses adjusted for sex, age, body weight and malnutrition showed that a serum reduced Alb ratio was significantly associated with IDPI (odds ratio = 0.962, 95% confidence interval = 0.926-0.999), whereas serum albumin concentration was not (odds ratio = 0.549, 95% confidence interval = 0.285-1.061). CONCLUSIONS: A serum reduced Alb ratio would be a useful indicator of protein insufficiency among community-dwelling older adults.

Exercise, Dietary Habits, and Defecatory Dysfunction in Patients Living with Colorectal Cancer: A Preliminary Quantitative Study.

This study investigated the association of exercise and dietary habits with defecatory dysfunction in patients living with colorectal cancer. We recruited 61 adult patients who had undergone surgery within the past 20 years and attended outpatient clinics at designated cancer hospitals in Japan. Defecatory dysfunction was defined as any symptom caused by issues with colon and anal function, including fecal incontinence, evacuation difficulties, frequent stools, diarrhea, and constipation. Exercise and dietary habits were assessed via a quantitative questionnaire survey. Postoperative defecatory dysfunction occurred in all the patients. Multivariate analysis revealed no association between exercise habits and defecatory dysfunction; however, dietary fiber intake ≥4 times a week was associated with frequent stools (adjusted odds ratio, 5.11; 95% confidence interval, 1.10, 23.70). These findings suggest a need to alleviate defecatory dysfunction by improving one's dietary habits. Interventions aimed at alleviating defecatory dysfunction by improving the dietary habits in patients living with colorectal cancer are needed.

Aging trajectories of subscales in higher-level functional capacity among community-dwelling older Japanese adults: the Otassha study.

BACKGROUND: Maintaining higher-level functional capacity is important for independent living in older age. The aging trajectory of the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) has three patterns; however, the subscale patterns are unclear. AIMS: This study aimed to clarify the aging trajectory patterns of the TMIG-IC subscales among community-dwelling older Japanese. METHODS: Participants were 3,169 community-dwelling older Japanese who participated in the 2012-2022 mail survey of the Otassha study. The aging trajectory patterns of the TMIG-IC total and subscale scores for those aged 65-90 years were identified using group-based trajectory modeling. Further, the combination frequency of the subscale trajectory patterns was determined. RESULTS: Three patterns were identified: early-onset decreasing, late-onset decreasing, and high-stable. DISCUSSION: The instrumental activities of daily living (IADL) trajectory was maintained until approximately 80 years of age; however, chronic disease prevailed the most in the early-onset decreasing pattern. The early-onset decreasing pattern of intellectual activity (IA) was present in 25% of participants, showing impaired IA from 65 years of age. The late-onset decreasing pattern of social roles (SR) was present in 30% of participants, showing a sharp decline compared to other subscales. For many people, the patterns of decrease in SR and IA overlapped. CONCLUSIONS: To maintain higher-level functional capacity, interventions that include disease management and prevention of decline in IADL and increase the awareness of the social support provided throughout old age and interventions for people with an early decline in IA should be implemented.

Physical frailty predicts cognitive decline among community-dwelling older Japanese women: A prospective cohort study from the Otassha study.

BACKGROUND: Physical frailty and cognitive decline are common issues in geriatrics within an aging society, yet the association between them remains controversial. This study aims to evaluate the association between physical frailty and cognitive decline among community-dwelling older Japanese women. METHODS: A prospective cohort study was conducted in an urban area of Tokyo, Japan, involving community-dwelling older adults 65 years or older. Physical frailty was evaluated using the Japanese version of the Cardiovascular Health Study criteria, consisting of five components: shrinking, weakness, exhaustion, slowness, and low activity. Participants were classified as robust, pre-frail, or frail based on the presence of one or more criteria. Cognitive decline was defined as at least a three-point decrease in the Mini-Mental State Examination score from baseline. The association between physical frailty and cognitive decline was examined using binomial logistic regression, adjusting for potential confounders. The analysis yielded multivariable odds ratios (ORs) and 95 % confidence intervals (CIs), with robust participants using as the reference group. RESULTS: A total of 2,122 individuals participated in the baseline survey, with 805 included in the analysis (mean age: 72.9 ± 5.1 years). At baseline, 363 participants were classified as pre-frail, while 32 were classified as frail. During the two-year follow-up period, 68 participants experienced cognitive decline. The multivariable OR (95 % CI) for frailty, using robust as the reference, was 3.50 (1.13, 10.80). Furthermore, a linear relationship was observed between physical frailty and cognitive decline. CONCLUSION: Among older Japanese women, there exists a dose-response relationship between physical frailty status and cognitive decline.

Corrigendum: Sex-specific factors associated with acceptance of smartwatches among urban older adults: the Itabashi longitudinal study on aging.

[This corrects the article DOI: 10.3389/fpubh.2024.1261275.].

Proposal and validation of an equation to identify sarcopenia using bioelectrical impedance analysis-derived parameters.

OBJECTIVE: This study aimed to develop a simpler approach for diagnosing sarcopenia by using only bioelectrical impedance vector analysis parameters. METHODS: The study design was a cross-sectional study. The research was conducted based on the Itabashi Longitudinal Study on Aging, a community-based cohort study, with data collected from the 2022 and 2023 surveys in Itabashi Ward, Tokyo, Japan. The development cohort consisted of 1146 participants from the 2022 survey, and the validation cohort included 656 participants from the 2023 survey. Both cohorts were comprised of community-dwelling older adults with similar inclusion criteria. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 criteria. The logistic model utilized height divided by impedance at 50 kHz and phase angle to establish a new regression equation to identify sarcopenia. Regression equations were generated for the development cohort and validated for the validation cohort. Discriminatory ability was assessed using the area under the receiver operating characteristic curve (AUC) for men and women. RESULTS: The prevalence of sarcopenia was 20.7% and 14.8% in the development and validation cohort, respectively. The AUC (95% confidence interval) of the logistic model in discriminating sarcopenia was 0.92 (0.88, 0.95) for men and 0.82 (0.78, 0.86) for women in the development cohort and 0.85 (0.78, 0.91) for men and 0.90 (0.86, 0.95) for women in the validation cohort. CONCLUSION: The study demonstrated that a simple formula using bioelectrical parameters at 50 kHz proved useful in identifying sarcopenia in the older adult population.

Feasibility, Acceptability, and Potential Efficacy of a Mobile Health Application for Community-Dwelling Older Adults with Frailty and Pre-Frailty: A Pilot Study.

Smartphone applications aimed at enhancing physical, cognitive, and social activities through mobile health (mHealth) technology are of increasing interest. Their feasibility and acceptability, alongside impacts on frailty phenotype scores and step counts among older adults with frailty, remain to be fully validated. This study presents a 13-week preliminary intervention trial assessing an mHealth app's feasibility in a cohort of 34 eligible older adults, including 5 frail and 29 pre-frail participants. The intervention entailed a 6-week course on app usage, followed by 7 weeks of observation, with four participants withdrawing early. Feasibility was determined by login and active use rates, with a target login rate of 60% or higher. Post-intervention, 100% session attendance and a median login rate of 88.4% were observed. Acceptability was high, with 73% affirming the app's health benefits. Notably, frailty scores and step counts improved post-intervention, underscoring the app's potential for supporting older adults with frailty.

Social isolation, regardless of living alone, is associated with mortality: the Otassha study.

Introduction: Social isolation has been recognized as a contributing factor to negative health outcomes. Although living alone is associated with health-related outcomes, existing findings are inconsistent. It is not the act of living alone that may predict poor health, but rather social isolation that can lead to increased mortality risk. This study investigated the combined associations of social isolation and living alone with mortality among community-dwelling older adults. Methods: We included older adults from Itabashi ward, Tokyo, who participated in comprehensive health checkups. Participants were categorized into four groups based on their social isolation status and living alone. The primary outcome was all-cause mortality, analyzed using Cox proportional hazards models. Results: Of the 1,106 participants (mean age 73, 42% male), 4.5% experienced both social isolation and living alone. This combination was associated with a worse prognosis regarding all-cause mortality (hazard ratio (HR): 2.08 [95% confidence interval (CI), 1.08-4. 00]). Those who were socially isolated but not living alone also showed a trend towards higher mortality risk (HR: 1.41 [95% CI, 0.90-2.20]). Contrastingly, those who were not socially isolated and lived alone did not show an increased mortality risk (HR: 0.81 [95% CI, 0.44-1.49]). Discussion and conclusion: Living alone is not inherently associated with a poor prognosis in older adults; however, social isolation was associated with a higher mortality risk. Healthcare providers should focus on enhancing social interactions and support for older adults because of their effects on health rather than solely addressing living arrangements to prevent adverse health events.

Sex-specific factors associated with acceptance of smartwatches among urban older adults: the Itabashi longitudinal study on aging.

Smartwatches (SW) are wearable devices that support daily life and monitor an individual's health and activity status. This information is utilized to promote behavior modification, which could help prevent chronic diseases and manage the health of older adults. Despite being interested in SWs, older adults tend to decrease their SW usage as they age. Therefore, understanding the acceptance of SWs among older individuals can facilitate individual health management through digital health technology. This study investigated the factors associated with the acceptance of SWs among older adults in Japan and the variations in the factors by sex. This study utilized data from the 2022 Itabashi Longitudinal Study on Aging, an ongoing cohort study conducted by the Tokyo Metropolitan Institute for Geriatrics and Gerontology. We included 899 eligible individuals aged ≥65 years. Participants were classified into three groups: possessing SW (possessor group), not possessing SW but interested in possession in the future (interest group), and not interested in possession in the future (non-interest group) using a self-administered questionnaire. The level of SW acceptance was operationally defined as follows: low (non-interest group), medium (interest group), and high (possessor group). Further, we evaluated the association of acceptance and purchase intentions of SWs with sociodemographic variables, technology literacy, and health variables. Among the participants, 4.2% possessed SWs, with no significant sex difference (men, 4.2%; women, 4.3%). Among men, age < 75 years, obesity, diabetes, and dyslipidemia were significantly associated with SW acceptance level. Contrastingly, among women, age < 75 years, living alone, higher household income, and a high score for new device use in the technology literacy category were significantly associated with SW acceptance level. Health-related factors were associated with SW acceptance in men, while technology literacy and sociodemographic factors were associated with SW acceptance in women. Our findings may inform the development of sex-specific interventions and policies for increasing SW utilization among older adults in Japan.

Prevalence of oral frailty and its association with dietary variety, social engagement, and physical frailty: Results from the Oral Frailty 5-Item Checklist.

AIM: This cross-sectional study had two aims: to assess the prevalence of oral frailty (OF), according to the Oral Frailty 5-Item Checklist (OF-5), among community-dwelling older adults; and to examine the associations among oral frailty, dietary variety, social engagement, and physical frailty. METHODS: We pooled data from two population-based studies (the Otassha Study and the Itabashi Longitudinal Study on Aging). With the OF-5, OF is characterized by the presence of two or more of the following: (i) fewer teeth, (ii) difficulty in chewing, (iii) difficulty in swallowing, (iv) dry mouth, and (v) low articulatory oral motor skills. We calculated the OF prevalence for each sex. We assessed dietary variety, social engagement, and physical frailty. Generalized structural equation modeling was employed to investigate the associations among oral frailty, low dietary variety (dietary variety score ≤3), social isolation (Lubben Social Network Scale score <12), and physical frailty (Japanese version of the Cardiovascular Health Study score ≥3). RESULTS: A total of 1206 individuals (626 women and 580 men) with a mean age of 74.7 years were included. The prevalence of OF was 36.7%, and it increased with age; however, there was no significant sex difference. OF was significantly indirectly associated with physical frailty via low dietary variety (odds ratio, 1.43; 95% confidence interval, 1.04-1.97) and social isolation (odds ratio, 1.42; 95% confidence interval, 1.04-1.94). CONCLUSIONS: Two of five community-dwelling older adults exhibited OF. Low dietary variety and social isolation are potential underlying mechanisms through which OF is indirectly associated with physical frailty. Geriatr Gerontol Int 2024; 24: 371-377.