[Cut-off point of the risk assessment scale for the 9-year risk of functional disability].

Objectives　This study aimed to examine the cut-off point of the Risk Assessment Scale (RAS) for predicting the 9-year risk of functional disability among older Japanese adults.Methods　This prospective, 9-year follow-up study used data from the Sasaguri Genkimon Study in Fukuoka. Of the 2,629 older adults who did not have functional disabilities and participated in the baseline survey in 2011, 2,254 with complete data were included in the analysis. The RAS was assessed using a questionnaire that showed good predictive and external validity for the 3-year risk of functional disability. The outcome was the incidence of functional disability during follow-up, which was defined as a new certification for the need for support or care. The cut-off point of the RAS was estimated as the point indicating the maximum χ2 value of the log-rank test. The predictive validity of the RAS for functional disability was examined using C-statistics for the total score, and sensitivity and specificity for the cut-off point, respectively. Participants were then categorized into two groups according to the cut-off point (high-score and low-score groups). Hazard ratio (HR) and 95% confidence interval (95% CI) of the 9-year risk of functional disability for the high-score group compared with the low-score group were calculated using the Cox proportional hazard model. In the multivariate model, HR was adjusted for living alone, education, economic status, drinking, smoking, and multimorbidity.Results　New functional disability was certified in 647 participants (28.7%) during a median follow-up period of 8.75 years. The cut-off point for functional disability was 13/14. The C-statistic was 0.774, and the sensitivity and specificity were 0.726 and 0.712, respectively. Compared to the low-score group (0-13 points), the HR (95% CI) of the high-score group (≥ 14 points) for incident functional disability in 9 years was 5.50 (4.62-6.54) in the crude model, and 4.81 (4.00-5.78) in the multivariate model (P<.001).Conclusion　This study, with its long follow-up period of 9 years, demonstrated that the 13/14 cut-off point of the RAS is suitable for the long-term assessment of functional disability risk. Our results suggest the possibility of using the 13/14 cut-off point of the RAS as a promising tool to grasp the risk of functional disability over a longer time frame, highlighting the potential for early prevention and intervention.

The relationship between working status in old age and cause-specific disability in Japanese community-dwelling older adults with or without frailty: A 3.6-year prospective study.

AIM: To examine the effects of employment engagement, classified by frailty and working status, on the incidence of disability in urban community-dwelling older adults. METHODS: We used data from 6386 initially nondisabled residents aged 65-84 years from Ota City, Tokyo, Japan, in 2016. The observation duration was 3.6 years. Self-administered questionnaires applied the Cox proportional hazard model by assessing the existence of frailty through Check-List 15 (with a score ≥4 indicating the state of frailty), controlling for age, sex, living situation, education level, equivalent income, chronic conditions, body mass index, instrumental activities of daily living, self-rated health, drinking and smoking status, and social activities. We evaluated the predictive value of working status (full-time, part-time, temporary, or nonworker) at baseline for cause-specific disability (dementia-type vs. non-dementia-type) incidence, identified using the long-term care insurance system's nationally unified database. RESULTS: Of the 6386 participants, 806 (63/1134 full-time workers; 58/1001 part-time workers; 61/547 temporary workers; 624/3704 nonworkers) presented with disabilities during the 3.6-year-long duration. Adjustments for conventional covariates showed that nonfrail full-time and part-time workers, as well as frail full-time workers, had significantly lower risks of all-cause disability incidence. Furthermore, nonfrail and frail full-time workers had significantly lower risks of dementia-type and nondementia-type disabilities, respectively. CONCLUSIONS: The incidence of disability in older adults was influenced by working and frailty status. Engaging in full-time work thus prevents disabilities in older adults, regardless of their frailty status. Meanwhile, nonfrail older adults are able to avoid disabilities even when engaging in part-time work. Geriatr Gerontol Int 2023; 23: 855-863.

Modifiable healthy behaviours and incident disability in older adults: Analysis of combined data from two cohort studies in Japan.

Healthy behaviours reduce the risk of incident disability; however, their components require further consideration. Specifically, little evidence exists on healthy behaviours that comprise modifiable factors, including social aspects, and their effects on those who do not engage in them. This study aimed to examine the association between engaging in healthy behaviours with modifiable factors and incident disability among community-dwelling older adults; as well as identify factors associated with nonengagement in healthy behaviours. We analysed data obtained from 1357 older adults aged 65 years and more without disabilities at baseline. The outcome was incident disability, which was defined based on the long-term care insurance certification in Japan. This study included regular exercise (≥1 day/week), favourable eating habits (≥4 dietary variety score), and social participation (engaging in two or more social activities) as components of healthy behaviours. We used the Cox proportional hazards model to calculate hazard ratios (HR) for incident disabilities. The proportion of those who satisfied all healthy behaviours was 21 %. During the follow-up period (median: 6.3 years), 282 incident disabilities were confirmed. Compared to those who engaged in one healthy behaviour, those who satisfied all healthy behaviours showed a 31 % (95 % confidence interval: 0.48, 0.98) lower HR of incident disability after adjusting for covariates. Current smoking and depressive mood were associated with non-engagement in healthy behaviours. This study found that having physically and socially active lifestyles and favourable eating habits are effective in reducing the risk of incident disability. Meanwhile, several older adults lack the components of a healthy lifestyle. Approaches that focus on multiple healthy behaviours are necessary to enhance the benefits of healthy lifestyles.

Combined Impacts of Physical Activity, Dietary Variety, and Social Interaction on Incident Functional Disability in Older Japanese Adults.

BACKGROUND: This 3.6-year prospective study examined combined impacts of physical activity, dietary variety, and social interaction on incident disability and estimated population-attributable fraction for disability reduction in older adults. METHODS: Participants were 7,822 initially non-disabled residents (3,966 men and 3,856 women) aged 65-84 years of Ota City, Tokyo, Japan. Sufficiency of moderate-to-vigorous-intensity physical activity (MVPA) ≥150 min/week, dietary variety score (DVS) ≥3 (median), and social interaction (face-to-face and/or non-face-to-face) ≥1 time/week was assessed using self-administered questionnaires. Disability incidence was prospectively identified using the long-term care insurance system's nationally unified database. RESULTS: During a follow-up of 3.6 years, 1,046 (13.4%) individuals had disabilities. Independent multivariate-hazard ratios (HRs) and 95% confidence intervals (CIs) of MVPA, DVS, and social interaction sufficiency for incident disability were 0.68 (95% CI, 0.59-0.78), 0.87 (95% CI, 0.77-0.99), and 0.90 (95% CI, 0.79-1.03), respectively. Incident disability HRs gradually reduced with increased frequency of satisfying these behaviors (any one: HR 0.82; 95% CI, 0.65-1.03; any two: HR 0.65; 95% CI, 0.52-0.82; and all three behaviors: HR 0.54; 95% CI, 0.43-0.69), in an inverse dose-response manner (P < 0.001 for trend). Population-attributable fraction for disability reduction in satisfying any one, any two, and all three behaviors were 4.0% (95% CI, -0.2 to 7.9%), 9.6% (95% CI, 4.8-14.1%), and 16.0% (95% CI, 8.7-22.8%), respectively. CONCLUSION: Combining physical activity, dietary variety, and social interaction substantially enhances the impacts on preventing disability among older adults, with evidence of an inverse dose-response manner. Improving insufficient behavior elements through individual habits and preexisting social group activities may be effective in preventing disability in the community.

Modifiable intrinsic factors related to occupational falls in older workers.

AIM: Identification of modifiable intrinsic factors for occupational falls is required for initiating effective fall prevention strategies for older workers. This study aimed to identify modifiable intrinsic factors related to falls during occupational activities among older workers. METHODS: This retrospective study involved 1164 older workers (aged ≥60 years, workdays ≥4/month) sampled from 18 public employment agencies for seniors in Saitama, Japan. Participants were assessed regarding the following 10 modifiable intrinsic factors: multimorbidity, polypharmacy, fall-risk-increasing medication use, self-rated vision and hearing, functional strength, bilateral stepping, standing balance, executive function and visuospatial ability. The number of falls during occupational activities in the past year was also recorded. RESULTS: In total, 111 falls occurred in 73 of the 1164 participants during occupational activities in the past year. A negative binomial regression model showed that use of fall-risk-increasing medications (incidence rate ratio [IRR]: 2.23, 95% confidence interval [CI]: 1.08, 4.60, P = 0.031), reduced functional strength (IRR: 1.81, 95% CI: 1.02, 3.21, P = 0.042), poor standing balance (IRR: 1.83, 95% CI: 1.09, 3.09, P = 0.023) and poor visuospatial ability (IRR: 1.56, 95% CI: 1.03, 2.36, P = 0.034) were independently associated with occupational falls. CONCLUSIONS: Our findings suggest that the assessment of medication use, functional strength, standing balance and visuospatial ability in regular health checks in the workplace may be useful for screening older workers at risk of occupational falls. Geriatr Gerontol Int 2022; 22: 338-343.

Dose-response relationships of sarcopenia parameters with incident disability and mortality in older Japanese adults.

BACKGROUND: Sarcopenia-related parameters may have differential impacts on health-related outcomes in older adults. We examined dose-response relationships of body composition, muscle strength, and physical performance with incident disability and mortality. METHODS: This prospective study included 1765 Japanese residents (862 men; 903 women) aged ≥65 years who participated in health check-ups. Outcomes were incident disability and all-cause mortality. Fat mass index (FMI) and skeletal muscle mass index (SMI), determined using segmental multi-frequency bioelectrical impedance analysis, handgrip strength (HGS), and usual gait speed (UGS) were measured. We determined multivariate-adjusted hazard ratios (HRs) for disability and mortality relative to sex-specific reference values (FMI: medians; SMI: 7.0 kg/m2 for men and 5.7 kg/m2 for women; HGS: 28 kg for men and 18 kg for women; or UGS: 1.0 m/s for both sexes). Association shapes were examined using restricted cubic splines or fractional polynomial functions. RESULTS: The median follow-up was 5.3 years; 107 (12.7%) men and 123 (14.2%) women developed disability, and 101 (11.7%) men and 56 (6.2%) women died. FMI did not impact any outcome in men and disability in women, while an FMI ≤ 7.3 kg/m2 (median) was significantly associated with higher mortality risk in women, compared with median FMI. SMI did not impact disability in either sex and mortality in women, but showed a significant inverse dose-response relationship with mortality risk in men [HRs (95% confidence intervals) of minimum and maximum values compared with the reference value: 2.18 (1.07-4.46) and 0.43 (0.20-0.93), respectively], independent of HGS and UGS. HGS and UGS showed a significant inverse dose-response relationship with disability in both sexes [HGS: 1.71 (1.00-2.91) and 0.31 (0.09-0.99), respectively, in men, 2.42 (1.18-4.96) and 0.41 (0.20-0.85), respectively, in women; UGS: 2.14 (1.23-3.74) and 0.23 (0.08-0.67), respectively, in men, 3.26 (2.07-5.14) and 0.11 (0.05-0.26), respectively, in women] and mortality in women [HGS: 6.84 (2.84-16.47) and 0.06 (0.02-0.21), respectively; UGS: 2.67 (1.14-6.27) and 0.30 (0.11-0.85), respectively], independent of body composition, but did not impact mortality in men. CONCLUSIONS: Disability risk was more dependent on muscle strength and physical performance in both sexes. Mortality risk in men was more dependent on muscle mass, and mortality risk in women was influenced by lower fat mass along with muscle strength and physical performance. Although improving muscle strength and physical performance should be the first target for health promotion, it is also necessary to pay attention to body composition to extend life expectancy in older adults.

[Trajectories of Dietary Variety Score among community-dwelling older Japanese and their related factors].

AIM: To categorize the age-related trajectories of dietary variety score (DVS) in the community-dwelling elderly and to examine the associated factors. METHODS: The study population included 1,195 people who underwent a medical checkup for the elderly in Kusatsu-town, Gunma Prefecture in 2012 to 2017. A multinomial logistic regression analysis was performed to examine the factors associated with the age-related trajectories of DVS. The dependent variables were sex, age, family structure, years of education, BMI, subjective chewing ability, TMIG-IC, GDS-15, MMSE, smoking, alcohol consumption, and history of hypertension, dyslipidemia, diabetes mellitus, and stroke. RESULTS: The adjusted odds ratio (95% confidence intervals) of the low trajectory group in comparison to the medium trajectory group were 2.69 (1.02-7.08) for subjective chewing ability (no chewing), 1.11 (1.06-1.17) for GDS-15, 1.76 (1.14-2.73) for current smoking, and 1.70 (1.19-2.43) for past smoking. In contrast, the adjusted odds ratio of the high trajectory group in comparison to the medium trajectory group were 0.61 (0.37-1.00) for men, 1.04 (1.01-1.07) for age, 0.58 (0.38-0.89) for subjective masticatory ability (difficult to chew), 0.88 (0.82-0.96) for GDS-15, and 0.55 (0.37-0.83) for a history of hypertension. CONCLUSIONS: The age-related trajectory patterns of DVS in the community-dwelling elderly can be categorized into three types. In order to maintain a high quality of food intake, it was shown that, in addition to subjective masticatory ability and mental health factors, such as depression, we should pay attention to the control of hypertension, which is a risk factor for lifestyle diseases, and lifestyle habits such as smoking.

Sarcopenia: prevalence, associated factors, and the risk of mortality and disability in Japanese older adults.

BACKGROUND: There is limited evidence on sarcopenia in Asian populations. This study aimed to clarify the prevalence, associated factors, and the magnitude of association with mortality and incident disability for sarcopenia and combinations of its components among Japanese community-dwelling older adults. METHODS: We conducted a 5.8 year prospective study of 1851 Japanese residents aged 65 years or older (50.5% women; mean age 72.0 ± 5.9) who participated in health check-ups. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 algorithm. Appendicular lean mass index (ALMI) was measured using direct segmental multi-frequency bioelectrical impedance analysis. A Cox proportional hazards regression model was used to identify associations of sarcopenia and the combinations of its components with all-cause mortality and incident disability. RESULTS: The prevalence of sarcopenia was 11.5% (105/917) in men and 16.7% (156/934) in women. Significant sarcopenia-related factors other than ageing were hypoalbuminaemia, cognitive impairment, low activity, and recent hospitalization (all P-values <0.05) among men and cognitive impairment (P = 0.004) and depressed mood (P < 0.001) among women. Individuals with sarcopenia had higher risks of mortality [hazard ratios (95% confidence interval): 2.0 (1.2-3.5) in men and 2.3 (1.1-4.9) in women] and incident disability [1.6 (1.0-2.7) in men and 1.7 (1.1-2.7) in women]. Compared with the individuals without any sarcopenia components, those having low grip strength and/or slow gait speed without low ALMI tended to have an increased risk of disability [1.4 (1.0-2.0), P = 0.087], but not mortality [1.3 (0.8-2.2)]. We did not find increased risks of these outcomes in participants having low ALMI in the absence of low grip strength and slow gait speed [1.2 (0.8-1.9) for mortality and 0.9 (0.6-1.3) for incident disability]. CONCLUSIONS: Japanese older men and women meeting Asian criteria of sarcopenia had increased risks of all-cause mortality and disability. There were no significant increased risks of death or incident disability for both participants with muscle weakness and/or low performance without low muscle mass and those with low muscle mass with neither muscle weakness nor low performance. Further studies are needed to examine the interaction between muscle loss, muscle weakness, and low performance for adverse health-related outcomes.

[Awareness of the term "frailty" and its correlates among older adults living in a metropolitan area].

Objectives　This study aimed to examine the awareness of the term "frailty" and its correlates among older adults living in a Japanese metropolitan area.Methods　We used baseline and 2-year follow-up data from a community-wide intervention on preventing frailty in Ota City, Tokyo. In July 2016, we conducted a self-administered questionnaire survey via mail to investigate the lifestyle and health status of 15,500 non-disabled residents aged 65-84 years from all 18 districts. In July 2018, we investigated the awareness of the term "frailty" in the same sample using a different questionnaire, and 10,228 people (4,977 men and 5,251 women) were included in the analyses. In addition, 9,069 people (4,347 men and 4,722 women) who responded to both 2016 and 2018 surveys were analyzed for correlates of awareness of the term "frailty." We categorized the responses "I know the meaning" or "I have heard of it but do not know the meaning" as awareness of the term. Decision tree and multilevel Poisson regression analyses were performed to examine the association of the following with awareness of "frailty": age, marital status, living situation, education, equivalent income, body mass index, number of chronic diseases, alcohol consumption, smoking status, Dietary Variety Score (DVS), and presence or absence of lower back and knee pains, depressive mood, exercise habits, social activity, social isolation, and frailty.Results　Awareness of the term "frailty" was estimated as 20.1% in total (15.5% in men and 24.3% in women). The subgroup with the highest "frailty" awareness was women who exercised, were socially active, and had a DVS of 4 or more (awareness of 36.3%). Significant independent correlates of "frailty" awareness were age (as per year: multivariate-adjusted prevalence ratio=1.03, [95% confidence interval=1.02-1.04]), sex (women: 1.35 [1.21-1.51]), educational attainment (high school: 1.27 [1.11-1.45], higher than junior college/vocational schools: 1.47 [1.28-1.70]), equivalent income (more than 2.5 million yen/year: 1.12 [1.01-1.25]), exercise habits (presence: 1.26 [1.11-1.43]), DVS (6 points or more: 1.37 [1.21-1.55]), social activity (presence: 1.33 [1.20-1.49]), social isolation (presence: 0.75 [0.67-0.85]), and frailty (presence: 0.72 [0.62-0.84]).Conclusions　Although many policies refer to "frailty," the level of awareness of the term among older adults was low. Older adults, especially women, who had higher socioeconomic status, better exercise and dietary habits, and stronger social connections, were significantly more aware of the term. In contrast, individuals who were socially isolated and/or frail did not know the term. Thus, it is crucial to develop specific measures to promote frailty prevention among high-risk individuals.

Healthy lifestyle behaviors and transitions in frailty status among independent community-dwelling older adults: The Yabu cohort study.

Frailty is a dynamic condition that can worsen or improve. Although previous studies have identified demographic and intrinsic factors associated with transitions in frailty status, less evidence is available regarding associations with daily activities. This longitudinal study examined associations of behavioral factors with incident frailty, adverse events (e.g. residence in a nursing home, hospitalization, and death), and frailty improvement among older adults. The analysis included data from 3,769 independent older adults aged 65 years or more (mean age, 76.3 ± 7.2years; proportion of frail participants, 30.1%) from the Yabu cohort study (baseline, 2012; follow-up, 2017). The Kaigo-Yobo Checklist, a standardized questionnaire, was used to assess frailty status (non-frail or frail) and seven behavioral factors: farming, shopping, exercise, eating habit, intellectual activity, social participation, and smoking. At the 5-year follow-up survey, the proportions of participants transitioning from non-frail to frail, from non-frail to incident adverse events, from frail to non-frail, and from frail to incident adverse events were 16.8%, 13.9%, 15.2%, and 50.1%, respectively. In the analysis of non-frail participants, farming, exercise, intellectual activity, and social participation were associated with lower odds of becoming frail and experiencing adverse events. In the analysis for frail participants, farming, intellectual activity, and social participation were significantly associated with improvement in frailty status, and farming, shopping, and social participation were associated with lower odds of incident adverse events. These findings suggest that farming, healthy daily activities, and social participation help improve and prevent frailty/adverse events.

[Impact of lifestyle-related diseases and frailty on the incidence of loss of independence in Japanese community-dwelling older adults: A Longitudinal Study on Aging and Health in Kusatsu].

Objectives　This study aimed to determine risk factors for frailty and lifestyle-related diseases impacting the incidence of loss of independence among Japanese community-dwelling older adults, and to measure the magnitude of these associations.Methods　We conducted an 8.1-year prospective study involving 1,214 residents of the town of Kusatsu, aged 65 years and over, who were initially free of disability and underwent the comprehensive geriatric assessment between 2002 and 2011. Loss of independence was defined as the incidence of disability or having died before the occurrence of disability was certified by the Long-Term Care Insurance program in Japan. Risk factors for lifestyle-related diseases and health status comprised hypertension, diabetes mellitus, overweight, chronic kidney disease, current smoking, past history of stroke, heart disease and cancer, frailty, underweight, anemia, hypoalbuminemia, and cognitive decline. Frailty was defined as the presence of three or more of the following criteria: Weight loss, weakness, exhaustion, slowness, and low levels of physical activity. Prefrailty was defined as the presence of one or two of these same criteria. Cox proportional-hazard regression model was used to estimate hazard ratios (HR) and the population attributable fraction (PAF) of loss of independence.Results　During the follow-up, 475 cases, including 372 disabilities and 103 deaths, were identified as having experienced loss of independence. The multivariable HRs for the loss of independence were 1.3 to 2.2-fold higher for the presence of frailty, past history of stroke, cognitive decline, prefrailty, and smoking. The PAF of loss of independence was the greatest for prefrailty (19%), followed by frailty (12%). The PAF was relatively large for prefrailty (19%) and smoking (11%) in men, and frailty (18%), prefrailty (18%), and chronic kidney disease (11%) in women. Stratified by age category, participants aged 65-74 years having frailty and several lifestyle-related diseases showed significantly higher HRs for loss of independence and greater PAFs for prefrailty (18%), frailty (13%), and smoking (11%).Conclusions　Loss of independence among Japanese community-dwelling older adults who underwent screening examinations was largely attributed to frailty and prefrailty. Our findings suggest that the screening and the intervention for frailty and lifestyle-related diseases in the early stages of old age might be beneficial in prolonging healthy life expectancy of Japanese community-dwelling older adults.

Associations of Walking Speed, Grip Strength, and Standing Balance With Total and Cause-Specific Mortality in a General Population of Japanese Elders.

OBJECTIVES: Walking speed, grip strength, and standing balance are key components of physical performance in older people. The present study aimed to evaluate (1) associations of these physical performance measures with cause-specific mortality, (2) independent associations of individual physical performance measures with mortality, and (3) the added value of combined use of the 3 physical performance measures in predicting all-cause and cause-specific mortality. DESIGN: Prospective cohort study with a follow-up of 10.5 years. SETTING: Tokyo Metropolitan Institute of Gerontology Longitudinal Interdisciplinary Study on Aging (TMIG-LISA), Japan. PARTICIPANTS: A total of 1085 initially nondisabled older Japanese aged 65 to 89 years. MEASUREMENTS: Usual walking speed, grip strength, and standing balance were measured at baseline survey. RESULTS: During follow-up, 324 deaths occurred (122 of cardiovascular disease, 75 of cancer, 115 of other causes, and 12 of unknown causes). All 3 physical performance measures were significantly associated with all-cause, cardiovascular, and other-cause mortality, but not with cancer mortality, independent of potential confounders. When all 3 physical performance measures were simultaneously entered into the model, each was significantly independently associated with all-cause and cardiovascular mortality. The C statistics for all-cause and cardiovascular mortality were significantly increased by adding grip strength and standing balance to walking speed (P < .01), and the net reclassification improvement for them was estimated at 18.7% and 7.5%, respectively. CONCLUSION: Slow walking speed, weak grip strength, and poor standing balance predicted all-cause, cardiovascular, and other-cause mortality, but not cancer mortality, independent of covariates. Moreover, these 3 components of physical performance were independently associated with all-cause and cardiovascular mortality and their combined use increased prognostic power.