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.

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.

Associations between information and communication technology use and frailty in community-dwelling old-old adults: results from the ILSA-J.

OBJECTIVES: Frailty is a significant cause of adverse health events including long-term care and hospitalization. Although information and communication technology (ICT) has become an integral part of modern life, it remains unclear whether ICT use is associated with frailty. DESIGN: A cross-sectional study (Integrated Longitudinal Studies on Aging in Japan, ILSA-J). SETTING AND PARTICIPANTS: Aged 75 and older data from the ILSA-J in 2017 (n = 2893). METHODS: ICT use was measured using the technology usage sub-items of the Japan Science and Technology Agency Index of Competence. Specifically, the use of mobile phones, ATMs, DVD players, and sending e-mails were rated as "yes" (able to do) or "no" (unable to do), with the first quintile (≤1 point) defined as ICT non-users. Frailty was assessed using the Japanese version of the Cardiovascular Health Study criteria based on the phenotype model (e.g., weight loss, slowness, weakness, exhaustion, and low activity). Further, multivariate logistic regression analysis analyzed its association with ICT use. Subgroup analyses were stratified according to gender, years of education, and living arrangements. RESULTS: Higher ICT use was not associated with frailty after adjusting for covariates (odds ratio [OR]: 0.53; 95%CI 0.39-0.73). Similar associations were found in the sub-groups of women (OR 0.45, 95%CI 0.30-0.66), <13 years of education (OR 0.48, 95%CI 0.34-0.67), living alone (OR 0.46, 95%CI 0.27-0.79), and living together (OR 0.57, 95%CI 0.38-0.85). No association existed between using ICT and frailty in the sub-groups of men and ≥13 years of education. CONCLUSIONS AND IMPLICATIONS: Higher ICT use is associated with the absence of frailty in individuals 75 years and older. Such benefits may be particularly pronounced in women, those with lower levels of education, and older adults living alone or with others.

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.

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.

Effects of Radio-Taiso on Health-Related Quality of Life in Older Adults with Frailty: A Randomized Controlled Trial.

BACKGROUND: Radio-Taiso could be a sustainable public health strategy for maintaining quality of life (QoL) in older adults with frailty. This study aimed to investigate whether Radio-Taiso provided greater benefits for health-related quality of life (HR-QoL) and to identify the mechanisms underlying the effectiveness in this population. METHODS: A 12-week randomized controlled trial enrolled 226 older Japanese adults with pre-frailty or frailty, assessed using the modified frailty phenotype. Participants were randomly allocated to the intervention (Radio-Taiso + nutrition program) or control (nutrition program) groups. The Radio-Taiso program comprised five 60-min group sessions and daily practice at the participants' homes. The primary outcome was the change in the mental domain of HR-QoL, assessed using the SF-36®. The secondary outcomes included six physical fitness items and exercise self-efficacy. RESULTS: Overall, 104 and 105 participants in the intervention and control groups, respectively, were analyzed based on the intention-to-treat principle. The median (interquartile range) daily practice rate of Radio-Taiso was 94.1% (73.2-98.8%). Although general linear models adjusted for baseline values and allocation stratification factors showed that the intervention group obtained greater benefits (adjusted mean differences [95% confidence intervals]) in the up-and-go (0.3 [0.1, 0.6] s), 2-min step-in-place (-3.2 [-6.2, -0.2] steps) tests, and exercise self-efficacy scale (-1.4 [-2.6, -0.1] points) than the control group, there were no group differences in changes in the mental domain score of HR-QoL. CONCLUSIONS: Radio-Taiso provided greater benefits for agility/dynamic balance, aerobic endurance, and exercise self-efficacy in older adults with frailty; however, these changes do not improve HR-QoL.

Higher-level competence: Results from the Integrated Longitudinal Studies on Aging in Japan (ILSA-J) on the shape of associations with impaired physical and cognitive functions.

AIM: This study aimed to examine the relationships between levels of competence and impaired physical and cognitive functions in older adults. METHODS: We used a data set of the Integrated Longitudinal Studies on Aging in Japan for 2017 including 5475 community-dwelling older adults. Levels of competence were assessed using the Japan Science and Technology Agency Index of Competence (JST-IC). Grip strength (low grip strength: <28 kg for men and <18 kg for women) and gait speed (slow gait speed: <1.0 m/s for both sexes) were evaluated as physical function measurements, and the Mini-Mental State Examination (cognitive decline: <24 on the Mini-Mental State Examination) was used to assess cognitive function. RESULTS: The JST-IC had areas under the curve estimated from receiver operating characteristic analysis ranging from 0.65 to 0.73 for detecting low function as assessed by these tests. Restricted cubic spline curves showed that the shape of the association between the JST-IC and impaired function depended on sex and the test used. The comparison between perfect and imperfect JST-IC scores showed significant differences in the prevalence of low grip strength in both sexes, slow gait speed in women, and cognitive decline in men. CONCLUSIONS: It may be insufficient to identify those with impaired physical or cognitive function using the JST-IC. The shape of the association with the JST-IC varies across their measurements. Our findings can help interpret JST-IC scores in the context of low physical and cognitive functions. Geriatr Gerontol Int 2024; 24: 352-358.

Identification of a novel biomarker for sarcopenia diagnosis using serum metabolomic analysis: a pilot study.

PURPOSE: This pilot study compared serum metabolites in participants with and without sarcopenia. METHODS: Metabolomic techniques were applied to identify serum metabolites and novel biomarkers specific to patients with sarcopenia. In accordance with AWGS2019 criteria, sarcopenia was defined as low muscle mass plus either low muscle strength/low physical function, and severe sarcopenia was defined as low muscle mass, low muscle strength, and low physical function all together. RESULTS: The sarcopenia group had higher hypoxanthine, galactose, and mannose levels but lower triethanolamine and homogentisic acid levels than the non-sarcopenia group. The severe sarcopenia group had lower levels of alpha-tocopherol than the mild and moderate sarcopenia groups. CONCLUSION: This study is the first to identify hypoxanthine as a potential biomarker for sarcopenia in humans and provides new insights into the pathophysiology of sarcopenia. Furthermore, the identified metabolites may be useful for the early detection of sarcopenia.

Associations of polypharmacy with frailty severity and each frailty phenotype in community-dwelling older adults: Itabashi Longitudinal Study on Aging.

AIM: Although polypharmacy and frailty are concerns in older adults, there is limited understanding of their association, particularly regarding frailty severity and its phenotypes within this population. This study aimed to examine the association between polypharmacy and frailty severity or frailty phenotypes in community-dwelling older Japanese adults. METHODS: This cross-sectional study included 1021 older adults from the Itabashi Longitudinal Study on Aging. Men accounted for 45.4%, and the mean age (standard deviation) was 77.9 (5.1) years. Participants were classified into frail (n = 67), pre-frail (n = 543), and robust (n = 411) groups using the revised Japanese Cardiovascular Health Study criteria. Polypharmacy was defined as using five or more self-reported prescription drugs. Ordinal and binomial logistic regression analyses examined the association between polypharmacy and frailty severity or frailty phenotypes (weight loss, weakness, exhaustion, slowness, and low activity). These models were adjusted for age, sex, body mass index, number of comorbidities, living status, employment status, years of education, as well as drinking and smoking habits. RESULTS: The prevalence of frailty in participants with and without polypharmacy was 10.1% and 5.0%, respectively. Participants with polypharmacy were more likely to have frailty (adjusted odds ratio [95% confidence interval], 1.89 [1.40-2.57]), weight loss (1.81 [1.00-3.27]), weakness (1.50 [1.08-2.09]), and slowness (2.25 [1.29-3.94]) compared with the no-polypharmacy group. CONCLUSIONS: Polypharmacy was associated with frailty severity and three frailty phenotypes. Longitudinal studies are required to investigate whether polypharmacy can predict the development and progression of frailty. Geriatr Gerontol Int 2024; 24: 196-201.

Questionnaire for Medical Checkup of Old-Old is non-inferior to the Kihon Checklist in screening frailty among independent older adults aged 75 years and older: The Itabashi Longitudinal Study on Aging.

AIM: The Questionnaire for Medical Checkup of Old-Old (QMCOO) is a 15-item dichotomous questionnaire developed for the early detection and intervention of frailty in a nationwide health checkup program targeting the old-old (i.e. aged ≥75 years). The Kihon Checklist (KCL) is a 25-item questionnaire widely used for screening and self-monitoring frailty status in administrative settings. With fewer items than the KCL, the QMCOO might expedite the frailty screening process. This study tested whether the QMCOO shows noninferiority in detecting frailty compared with the KCL. METHODS: Overall, 645 participants aged ≥75 years in the Itabashi Longitudinal Study on Aging were assessed for their frailty status according to the revised Japanese version of the Cardiovascular Health Study criteria. They also completed the QMCOO and the KCL simultaneously. We compared the discriminative performance of the two questionnaires using non-inferiority testing with an operationally defined non-inferiority margin of 10% of the area under the receiver operating characteristic curve computed from the KCL. RESULTS: The prevalence of frailty was 8.8%. The area under the receiver operating characteristic curve for the QMCOO in determining frailty was 0.76 (95% CI 0.70, 0.82), and the corresponding area under the receiver operating characteristic curve for the KCL was 0.77 (95% CI 0.69, 0.84). The QMCOO was not inferior to the KCL for frailty discrimination (P for non-inferiority = 0.006). CONCLUSIONS: The accuracy of the QMCOO for determining frailty was not inferior to that of the KCL. The QMCOO might be more acceptable and useful, as it can be applied in a shorter time with fewer questions than the KCL. Geriatr Gerontol Int 2024; 24: 176-181.

Relationship between phase angle and lower-extremity function in older adults: Itabashi Longitudinal Study on Aging.

OBJECTIVE: Evaluating muscle quality instead of its mass has gained attention in diagnosing sarcopenia. The aim of this study was to examine whether phase angle (PhA) as a bioelectrical impedance analysis (BIA)-derived muscle quality indicator is associated with overall lower extremity function better than appendicular skeletal muscle mass index (ASMI) in community-dwelling older adults. METHODS: This cross-sectional study used data from the Itabashi Longitudinal Study on Aging, a community-based cohort study. A sex-stratified multivariate logistic regression analysis was conducted using PhA and ASMI as exposures, and low physical function defined as short physical performance battery score <10 as the outcome, adjusted for age, being overweight, knee pain, and non-communicable diseases. Discrimination of low physical function was compared using the receiver operating characteristic curve. RESULTS: This study included 1464 participants (age 76 [73-80] y; 757 women), with 58 men (8%) and 66 women (9%) exhibiting low physical function. The multivariate odds ratio (OR; 95% confidence interval [CI]) for low physical function among the highest quartile, compared with the lowest quartile were significant in PhA in multiple sites (e.g., OR, 0.09; 95% CI, 0.03-0.32] for men and 0.12; 95% CI, 0.04-0.33 for women in the left leg) but not in ASMI (OR, 0.51; 95% CI, 0.19-1.34 for men and 0.56; 95% CI, 0.21-1.47 for women). Legs and whole-body PhA outperformed the ASMI in discriminating low physical function (P < 0.001). CONCLUSION: PhA reflected physical function better than ASMI; using PhA instead of ASMI in BIA-based morphometric evaluation may add information on low physical function and enhance the diagnostic value of sarcopenia.

Association between dynapenia and cognitive decline in community-dwelling older Japanese adults: The IRIDE Cohort Study.

AIM: Muscle mass and strength correlate with cognitive function; however, it remains unclear whether dynapenia (i.e., muscle weakness with preserved muscle mass) is relevant. This study aimed to explore whether dynapenia is associated with global cognitive function in community-dwelling older Japanese adults. METHODS: This cross-sectional study used data from the Integrated Research Initiative for Living Well with Dementia Cohort Study, which pooled data from five community-based geriatric cohorts. Dynapenia was defined as muscle weakness without muscle mass loss according to the Asian Working Group for Sarcopenia criteria. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). An ordered logistic regression analysis was conducted with dynapenia as the exposure and with cognitive decline stages, defined as an MMSE score of 27-30 for normal cognition, 24-26 for possible cognitive decline, and <24 for cognitive decline, as the outcome, stratified by sex and adjusted for age, muscle mass, education, alcohol consumption, smoking habits, living alone, and non-communicable diseases. RESULTS: We analyzed data for 3338 participants (2162 female) with preserved muscle mass. Of these, 449 (13.5%) had dynapenia, and 79 (2.4%) exhibited cognitive decline. Multivariate odds ratios (95% confidence interval) for cognitive decline among those with dynapenia, compared with those without dynapenia, were 1.51 (1.02-2.24) for males and 2.08 (1.51-2.86) for females. CONCLUSIONS: Muscle weakness is associated with cognitive decline, even in individuals with preserved muscle mass. Further studies are needed to better understand the association between muscle weakness and cognitive decline over time in order to develop dementia prevention strategies for those with dynapenia. Geriatr Gerontol Int 2024; 24: 123-129.

Predictive Capability of 5 Sarcopenia Diagnostic Criteria for Fall Incidents in Older Japanese Women: The Otassha Study.

OBJECTIVES: The association between sarcopenia diagnosis according to various diagnostic criteria and falls is unclear. We examined the association between sarcopenia defined by 5 different international criteria, and fall and injurious fall numbers among older community-dwelling Japanese women. DESIGN: Prospective observational study. SETTING AND PARTICIPANTS: Two population-based cohort studies in Itabashi, Japan, were integrated, including 552 community-dwelling Japanese women >75 years of age. METHODS: Muscle mass, muscle strength, and physical performance were assessed by bioimpedance analysis, handgrip strength, and gait speed, respectively. We recorded the fall and injurious fall numbers for 1 year using a diary. The association between sarcopenia diagnosis defined by the Asian Working Group for Sarcopenia (AWGS) 2019, European Working Group on Sarcopenia in Older People 2, Foundation for the National Institutes of Health (FNIH), International Working Group on Sarcopenia, and Society on Sarcopenia, Cachexia, and Wasting Disorders, and fall numbers was assessed by Poisson regression analysis to estimate the incidence rate ratio (IRR) and 95% CI for the presence or absence of sarcopenia. RESULTS: Of 470 participants (mean age 77.1 ± 8.1 years), 144 reported a combined 352 falls. Overall, 80 individuals experienced a single fall, 64 experienced multiple falls, and 91 experienced injurious falls. Sarcopenia defined by the AWGS 2019 (IRR 1.39, 95% CI 1.10-1.76) and FNIH (IRR 2.55, 95% CI 1.99-3.26) was significantly associated with the number of falls. In addition, sarcopenia defined by the FNIH (IRR 2.72, 95% CI 1.84-4.03) was significantly associated also with the number of injurious falls. No significant association was observed between sarcopenia diagnosis based on the other definitions and fall outcomes. CONCLUSIONS AND IMPLICATIONS: The AWGS 2019 and FNIH sarcopenia definitions were associated with the fall and injurious fall numbers in older Japanese women, indicating they can help in predicting falls in this population.

Inverse Association between Cheese Consumption and Lower Cognitive Function in Japanese Community-Dwelling Older Adults Based on a Cross-Sectional Study.

Diet modification may contribute to the prevention of age-related cognitive decline. The association between dairy product consumption and cognitive function in older people remains unknown. We investigated whether cheese intake is associated with lower cognitive function (LCF) in community-dwelling older adults. This cross-sectional study included 1503 adults aged over 65 years. The analyzed data were obtained through face-to-face interviews and functional ability measurement. Cognitive function was assessed using the mini-mental state examination (MMSE), and a score ≤23 was defined as LCF. The prevalence of LCF was 4.6%, and this group had smaller calf circumference, slower usual walking speed, and a more frequent history of anemia than subjects with MMSE scores >23. After adjusting for confounding factors, logistic regression analysis revealed cheese intake (odds ratio (OR) = 0.404, 95% confidence interval (CI) = 0.198-0.824), age (OR = 1.170, 95% CI = 1.089-1.256), usual walking speed (OR = 0.171, 95% CI = 0.062-0.472) and calf circumference (OR = 0.823, 95% CI = 0.747-0.908) to be significant factors associated with LCF. Although the present study was an analysis of cross-sectional data of Japanese community-dwelling older adults, the results suggest that cheese intake is inversely associated with LCF.

Vitamin K insufficiency predicts incidence of frailty in community-dwelling older adults: The Otassha Study.

INTRODUCTION: Vitamin K is a fat-soluble vitamin discovered as an essential factor for blood coagulation. It is suggested that vitamin K can benefit several aging-related diseases, including osteoporosis, osteoarthritis, and dementia. We previously reported the cross-sectional association of vitamin K insufficiency with frailty in community-dwelling older adults. MATERIALS AND METHODS: In October 2020, a health examination of community-dwelling older adults (The Otassha Study) was performed, including frailty evaluation and blood tests. We used a ucOC and OC ratio (ucOC/OC) to indicate vitamin K insufficiency. One year later, we conducted a follow-up evaluation of frailty on 518 people who were not frail at baseline. The serum ucOC/OC at the baseline examination was divided into quartiles (Q1, Q2, Q3, and Q4). Odds ratio (OR) and 95% confidence interval (CI) were calculated using multivariate binary logistic regression for each quartile of ucOC/OC to determine the risk of incident frailty in the follow-up study, with the lowest quartile (Q1) as the reference. RESULTS: Among the 518 older adults who were not frail at baseline, 66 people (12.7%) became frail in the follow-up study. In the multivariate binary logistic regression analysis, setting the lowest quartile of ucOC/OC (Q1) as a reference, the OR of the incident frailty in the highest quartile (Q4) was 2.53 (95% CI 1.07, 4.92) which was significantly different from Q1. CONCLUSION: The findings of this longitudinal study suggest that vitamin K insufficiency has nutritional importance in predicting the future incidence of frailty in the Japanese older adult population.

Effects of Daily Consumption of Soy Products on Basic/Instrumental Activities of Daily Living in Community-Dwelling Japanese Women Aged 75 Years and Older: A 4-Year Cohort Study.

Introduction: Since soy isoflavones compensate for age-related estrogen reduction, adequate intake of soy products may prevent the decline in activities of daily living (ADL) due to estrogen reduction in women. However, it is unclear whether regular soy product intake prevents ADL decline. This study examined the effects of soy product consumption on basic/instrumental ADL (BADL/IADL) in Japanese women 75 years or older for 4 years. Materials and Methods: The subject population consisted of 1289 women aged 75 years or older living in Tokyo who underwent private health examinations in 2008. For 1114 (or 1042) participants without baseline BADL (or IADL) disability, we examined the association between baseline soy product consumption frequency and the BADL (or IADL) disabilities 4 years later using logistic regression analyses. The models were adjusted for baseline age, or further for dietary variety for food groups other than soy products, exercise and sport participation, smoking, pre-existing disease number, and body mass index. Results: Regardless of adjustment for potential confounding factors, less frequent soy product consumption was associated with higher BADL or IADL disability incidence. In the fully adjusted models, the trend toward a higher incidence of disabilities with less frequent soy product consumption was statistically significant for both BADL (p = 0.001) and IADL (p = 0.007). Conclusions: Those who consumed soy products more frequently at baseline were less likely to develop BADL and IADL disabilities after 4 years than those who did not. The results show that daily soy product consumption may prevent functional ADL decline in older Japanese women.

Age- and sex-specific associations between sarcopenia severity and poor cognitive function among community-dwelling older adults in Japan: The IRIDE Cohort Study.

Introduction: This study examined whether the association between sarcopenia severity and cognitive function differed according to sex and age in community-dwelling older adults in Japan. Methods: This is a cross-sectional study of older adults (age ≥ 65 years) consisting of five regional cohorts integrated as the Integrated Research Initiative for Living Well with Dementia (IRIDE) Cohort Study. Sarcopenia severity was determined based on the Asian Working Group for Sarcopenia 2019, which assessed grip strength, walking speed, and skeletal muscle mass index. Poor cognitive function was defined as a Mini-Mental State Examination score of ≤ 23. Odds ratios (ORs) and 95% confidence intervals (CIs) for poor cognitive function were calculated by sex and age group (65-74 and ≥75 years) using binomial logistic regression models, which were adjusted for age, educational attainment, history of non-communicable diseases, smoking and drinking habits, living alone, frequency of going outdoors, exercise habits, and depressive symptom. Results: Of the 8,180 participants, 6,426 (1,157 men aged 65-74 and 1,063 men aged 75 or older; 2,281 women aged 65-74 and 1,925 women aged 75 or older) were analyzed. The prevalence ratio of sarcopenia and severe sarcopenia were 309 (13.9%) and 92 (4.1%) among men and 559 (13.3%) and 166 (3.7%) among women, respectively. A total of 127 (5.8%) men and 161 (3.9%) women had a poor cognitive function. Setting non-sarcopenia as a reference, the adjusted ORs (95% CI) of poor cognitive function were 2.20 (1.54, 3.15) for sarcopenia and 3.56 (2.20, 5.71) for severe sarcopenia. A similar trend was observed in analyses stratified by sex and age, with linear associations (P for trend <0.05) in both categories. Furthermore, there was a significant interaction (P < 0.05) between sex and sarcopenia severity, indicating a stronger linear association of sarcopenia severity with poor cognitive function in women compared with men. Discussion and conclusion: Sarcopenia severity was linearly associated with poor cognitive function in adults aged ≥ 65 years, with a stronger association in women compared with men.