Risk Of Incident Functional Disability Research Articles

Accelerometer-measured sedentary behavior and risk of functional disability in older Japanese adults: a 9-year prospective cohort study

BackgroundThe associations of sedentary time and patterns with functional disability among older adults remain unclear, and few studies have accounted for the co-dependency of sedentary behavior and physical activities when modeling sedentary behavior with risk of functional disability. We aimed to examine the associations between sedentary time and patterns and risk of incident functional disability, and assess whether replacing sedentary time with light physical activity (LPA) or moderate-to-vigorous intensity physical activity (MVPA) is associated with reduced risk of functional disability in community-dwelling older adults.MethodsA total of 1,687 Japanese adults aged ≥ 65 years without functional disability at baseline were prospectively followed-up for 9 years (2011–2020). Functional disability was ascertained using the national database of Japan’s Long-term Care Insurance System. Sedentary time and patterns, LPA, and MVPA were measured using a tri-axial accelerometer secured to participants’ waists.ResultsDuring follow-up, 466 participants developed functional disability. Compared with the lowest quartile of total sedentary time, the multivariable-adjusted hazard ratios (95% confidence intervals) of functional disability for the second, third, and top quartiles were 1.21 (0.91‒1.62), 1.45 (1.10‒1.92), and 1.40 (1.05‒1.88) (p for trend = 0.01). After further adjusting for MVPA, total sedentary time was no longer significantly associated with the risk of functional disability (p for trend = 0.41). Replacing 10 min/day of sedentary time with the same amount of MVPA (but not LPA) was significantly associated with a 12% reduced risk of functional disability (hazard ratio [95% confidence interval]: 0.88 [0.84‒0.92]). No significant association was observed between sedentary bout length and functional disability.ConclusionHigher levels of total sedentary time were associated with an increased risk of incident functional disability. However, this association was not independent of MVPA. Replacing sedentary time with MVPA, but not LPA, was associated with reduced risk of functional disability in older adults.

Association between Social Isolation and the Risk of Incident Functional Disability in Elderly Survivors after the Great East Japan Earthquake.

Social isolation is frequently observed among survivors of disaster. However, there is limited evidence regarding the association between social isolation and adverse health outcomes among survivors of disaster. The purpose of this study was to investigate the association between social isolation and the risk of incident functional disability (IFD) among survivors of the 2011 Great East Japan Earthquake (GEJE). We conducted a prospective cohort study of 1,039 residents aged ≥ 65 years who lived in four areas affected by the GEJE. Information regarding social isolation and other lifestyle factors was collected between June and November 2011 via a self-reported questionnaire. Social isolation was assessed using the Lubben Social Network Scale-6 (LSNS-6). Data regarding the incidence of functional disability were retrieved from the Long-term Care Insurance database. The Cox model was used to calculate multivariate hazard ratios (HRs) and 95% confidence intervals (CIs) for IFD. During 7,030 person-years of follow-up, 300 cases of IFD were certified (42.7disability events per 1,000 person-years). Social isolation was associated with increased risk of IFD in disaster survivors (HR = 1.32, 95% CI = 0.98-1.76). In addition, this association tended to be more remarkable among men and those whose houses were completely/seriously damaged. The present results suggest us that it would be possible to identify those who are more likely to be affected by social isolation after disaster. This finding would be useful in screening and supporting high risk group right after the occurrence of disaster.

Association of Arterial Stiffness with Functional Disability and Mobility Limitation: The Rugao Longitudinal Ageing Study.

Arterial stiffness is a common issue that may represent an indicator of vascular ageing. We aimed to investigate the association of arterial stiffness with the risk of functional disability and mobility limitation in older adults. Prospective cohort study. A total of 1699 older adults from the Rugao Longitudinal Ageing Study were included and analysed. Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV). Functional disability and mobility limitation were evaluated by the activities of daily living and the Timed Up and Go test, respectively. The associations of baPWV and risk of functional disability and mobility limitation were analysed using logistic regression models. Restricted cubic spline regressions were applied to estimate the possible nonlinear relationships between them. During the 3.5-year follow-up, 97 (10.00%) and 285 (31.11%) individuals were defined as new-onset functional disability and mobility limitation, respectively. After adjusting for confounding factors, elevated baPWV was significantly associated with a higher risk of incident functional disability (odds ratio [OR] 1.18, 95% confidence interval [CI] 1.06-1.31) and mobility limitation (OR 1.08, 95% CI 1.01-1.16). Additionally, consistent results were obtained from the stratified analyses of the different subgroups. Multivariable restricted cubic spline regression analysis further demonstrated that a near-linear association occurred between baPWV and the risk of incident functional disability and mobility limitation (P-overall < 0.01, P-nonlinear >0.05). Arterial stiffness, as assessed by baPWV, was associated with the risk of functional disability and mobility limitation in this community-based cohort, and these associations were nearly linear.

The association between psychological distress and risk of incident functional disability in elderly survivors after the Great East Japan Earthquake: The mediating effect of lifestyle and bodily pain

Background: We previously reported that psychological distress was associated with an increased risk of functional disability. However, the mechanism of the association remains unclear. Our aim was to estimate the mediating effect of lifestyle and bodily pain on the association among elderly survivors after the Great East Japan Earthquake.Methods: The study population comprised 1037 residents aged ≥ 65 years. The baseline surveys (exposure and mediators) were conducted in 2011. We classified participants into three categories according to their Kessler 6 score (low: 0–9, moderate: 10–12, and high: 13–24) and defined functional disability as certification for long-term care insurance in Japan. The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident functional disability according to Kessler 6 categories and explored the mediating effects of lifestyle and bodily pain on the association.Results: During approximately 8 years of follow-up, we documented 271 incident cases of functional disability. Compared with those in the low distress group, the multivariate adjusted HR for incident functional disability was 1.95 (95% CI 1.21–3.13) for those in the high distress group. Time spent walking, going out, and bodily pain significantly mediated the association between psychological distress and incident functional disability by 10.2%, 10.5%, and 10.3% for the high distress group, respectively.Limitations: We did not consider unmeasured confounders and use of appropriate medication.Conclusions: The evaluation and treatment of bodily pain as well as promotion of active lifestyle would be important for preventing disability among disaster survivors.

Subgroup characteristics of the association between volunteering and the risk of functional disability among older Japanese people: The Tsurugaya project

Background and objectiveAlthough it has been well known that volunteering is associated with a significantly decreased risk of incident disability among older people, it remains unanswered which subgroups of older people the above association is most remarkable. We aimed to identify such subgroups by conducting subgroup analyses for age, sex, chronic medical condition, and socio-demographic factors. MethodsParticipants were 826 Japanese community-dwelling people aged ≥70 years who lived in Tsurugaya, Sendai. Volunteering status was assessed with a baseline survey conducted in 2003. Incident functional disability was defined as the first certification of Long-term Care Insurance until 2017. The Cox proportional hazard model was used to estimate the multivariate-adjusted hazard ratios (HR) with 95% confidence intervals (CI) for incident functional disability. Subgroup analyses were conducted according to sex, age, medical history, marital status, and educational level. ResultsThe association between current volunteering and the risk of incident functional disability was not significant (HR 0.77, 95% CI 0.56–1.06) compared to non-volunteers. In the subgroup analysis, the association between current volunteering and the risk of incident functional disability was significant among participants who were women (HR 0.52, 95% CI 0.30–0.91), those who were aged 75 years or over (HR 0.57, 95% CI 0.36–0.91), and those living without a spouse (HR 0.47, 95% CI 0.24–0.91). ConclusionThe association between volunteering and a decreased risk of incident functional disability was remarkable among vulnerable groups such as women, those aged 75 years or over, those living without a spouse.

Reduced occlusal force and the risk of incident functional disability in community-dwelling dentate older people -Examination based on stratification of the number of remaining teeth-

Reduced occlusal force and the risk of incident functional disability in community-dwelling dentate older people -Examination based on stratification of the number of remaining teeth-

Combined effects of body mass index and unhealthy behaviors on disability in older Japanese adults: the Okayama study

BackgroundBody mass index (BMI) is a significant predictor of functional disability in older adults. However, when evaluated, the association between BMI and incident functional disability, considering behaviors only as covariates or not, may not be appropriate. The primary purpose of the study was to investigate the combined effects of BMI and unhealthy behaviors on the risk of incident functional disability.MethodsThis was a retrospective cohort study that took place in Okayama City, Japan. Data on BMI and unhealthy behaviors were obtained using the health check-up questionnaire. The certification of Long-Term Care Insurance was used to measure functional disability. Cox proportional hazard models were used; adjusted hazard ratios (HRs) with 95% confidence interval (CI) were calculated for incidence of functional disability across categories of BMI and number of unhealthy behaviors.ResultsThe relationship between BMI and incident functional disability was U-shaped (HR = 1.18, 95% CI [1.11–1.25], among the underweight range; and 1.26 [1.19–1.34] among the obesity range), and its risk was significantly higher within the normal-to-overweight range of BMI values with co-occurring unhealthy behaviors (with normal weight range and one, 1.17 [1.01–1.21]; two, 1.29 [1.18–1.41]; and three or four unhealthy behaviors 1.38 [1.24–1.54]; as well as among overweight range and one, 1.16 [1.05–1.27]; two, 1.26 [1.15–1.38]; and three or four unhealthy behaviors, 1.47 [1.31–1.64]). In each BMI category, the risk of incident functional disability increased with increasing number of unhealthy behaviors (p < 0.05 for linear tread), with the highest risk (1.87 [1.58–2.20]) occurring in combination with at least three unhealthy behaviors with BMI ≥ 27.5, for both sexes (2.20 [1.64–2.92] in men and 1.66 [1.35–2.04] in women).ConclusionIt is necessary to consider the combined effects of BMI and behaviors on incident functional disability. Furthermore, interventions targeting multiple behaviors should be considered as such interventions may offer greater benefits than simple interventions.

Association between improved adherence to the Japanese diet and incident functional disability in older people: The Ohsaki Cohort 2006 Study.

Although it has been reported that the Japanese dietary pattern is associated with a lower risk of incident functional disability among older people, the potential benefits of improving adherence to the Japanese diet remain unclear. The aim of the present study was to evaluate the association between 12-year change in adherence to the Japanese diet and the subsequent risk of incident functional disability in older people in Japan. We analyzed 10-year follow-up data from a cohort study of 2923 Japanese older adults (age ≥65 years) in 2006. We collected dietary information using a validated 39-item food frequency questionnaire at two time points (1994 and 2006). Adherence to the Japanese diet (high intake of rice, miso soup, seaweeds, pickles, green and yellow vegetables, fish, green tea; low intake of beef and pork, and coffee) was assessed using the Japanese Diet Index (JDI), which ranges from 0 to 9. Participants were categorized into five groups according to changes in the JDI score at these two time points. Data on incident functional disability from December 2006 to November 2016 were retrieved from the public long-term care insurance database. The Cox proportional hazards model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident functional disability. During 22,466 person-years of follow-up, 1093 cases of incident functional disability were documented. Compared with participants in the group with the largest decrease in the JDI score (≤-2), the multivariate-adjusted HR (95% CI) of incident functional disability was 0.77 (0.61-0.98) for those in the largest increase group (≥+2). Improved adherence to the Japanese diet was associated with a significantly lower risk of incident functional disability in older people in Japan.

Association between social participation and incident risk of functional disability in elderly Japanese: The Ohsaki Cohort 2006

BackgroundAlthough several longitudinal studies have examined the relationship between social participation and incident functional disability, the related mechanisms have remained unclear. The aim of this study was to examine the mechanisms linking social participation to incident functional disability. MethodsWe analyzed follow-up data for 11,992 older adults (≥65 years) participating in a community-based, prospective cohort study covering a 9-year period. At the baseline, the subjects were asked about three types of participation in community activities (volunteering, hobbies, and neighborhood associations) and the frequency of their participation. Data on incident functional disability were retrieved from the public Long-term Care Insurance database. The Cox model was used to estimate the multivariate-adjusted hazard ratios of incident functional disability. We then conducted mediation analysis to assess the magnitude of the mediating effect. ResultsAmong 84,760 person-years of follow-up, there were 3,984 cases of incident functional disability. The hazard ratio was 0.79 (95% CI: 0.73-0.86) for participating in one type of activity, 0.82 (95% CI: 0.74-0.90) for two types of activity and 0.70 (95% CI: 0.64-0.77) for three types of activity in comparison with no participation in any activity. Among the estimated mediating effects, cognitive activity accounted for 9.3%, time spent walking for 8.3%, psychological state for 4.6%, and social support for 2.8% of the reduced risk of incident functional disability. ConclusionThe results of this population-based cohort study indicate that cognitive activity and time spent walking are important mechanisms linking social participation to incident functional disability.

Impact of oral self-care on incident functional disability in elderly Japanese: the Ohsaki Cohort 2006 study

ObjectivesTo assess whether oral self-care (tooth brushing, regular dental visits and use of dentures) affects incident functional disability in elderly individuals with tooth loss.DesignA 5.7-year prospective cohort study.SettingOhsaki City, Japan.Participants12...

Sense of life worth living (ikigai) and incident functional disability in elderly Japanese: The Tsurugaya Project

ObjectiveTo test the hypothesis that elderly persons who feel ikigai (a sense of life worth living) have a lower risk of incident functional disability than those who do not. Recent studies have suggested that ikigai impacts on mortality. However, its impact upon disability is unknown. The aim of the present study was to investigate the association between ikigai and incident functional disability among elderly persons. MethodsWe conducted a prospective cohort study of 830 Japanese elderly persons aged ≥70years as a comprehensive geriatric assessment in 2003. Information on ikigai was collected by self-reported questionnaire. Data on functional disability were retrieved from the public Long-term Care Insurance database in which participants were followed up for 12years. Hazard ratios (HRs) and 95% confidence intervals (CIs) for incidence of functional disability were calculated for three groups delineated according to the presence of ikigai (“no”, “uncertain” or “yes”) using the Cox proportional hazards regression model. ResultsThe 12-year incidence of functional disability was 53.3% (442 cases). As compared with the “no” group, the multiple-adjusted HR (95% CI) of incident functional disability was 0.61 (0.36–1.02) for the “uncertain” group and 0.50 (0.30–0.84) for the “yes” group. ConclusionA stronger degree of ikigai is significantly associated with a lower risk of incident functional disability.

Body mass index and the risk of incident functional disability in elderly Japanese: The OHSAKI Cohort 2006 Study.

The relationship between the body mass index (BMI) and the incidence of cause-specific disability remains unclear.We conducted a prospective cohort study of 12,376 Japanese individuals aged ≥65 years who were followed up for 5.7 years. Information on BMI and other lifestyle factors was collected via a questionnaire in 2006. Functional disability data were retrieved from the public Long-term Care Insurance database. BMI was divided into 6 groups (<21, 21-<23, 23-<25, 25-<27[reference], 27-<29 and ≥29). Hazard ratios and 95% confidence intervals for cause-specific disability were estimated using Cox proportional hazards regression models.A U-shaped relationship between BMI and functional disability was observed, with a nadir at 26. The nadir BMI values with the lowest disability risk were 28 for dementia, 25 for stroke, and 23 for joint disease. A low BMI (<23) was a risk factor for disability due to dementia, the HR values (95% CI) being 2.48 (1.70-3.63) for BMI <21 and 2.25 (1.54-3.27) for BMI 21 to <23; a high BMI (≥29) was a risk factor for disability due to joint disease, the HR value (95% CI) being 2.17 (1.40-3.35). There was no significant relationship between BMI and disability due to stroke.The BMI nadirs for cause-specific disability differed: a low BMI (<23) was a risk factor for disability due to dementia, and a high BMI (≥29) was a risk factor for disability due to joint disease. Because BMI values of 23 to <29 did not pose a significantly higher risk for each cause of disability, this range should be regarded as the optimal one for the elderly population.

Early Cognitively Based Functional Limitations Predict Loss of Independence in Instrumental Activities of Daily Living in Older Adults.

Older adults with early forms of neurodegenerative disease are at risk for functional disability, which is often defined by the loss of independence in instrumental activities of daily living (IADLs). The current study investigated the influence of mild changes in everyday functional abilities (referred to as functional limitations) on risk for development of incident functional disability. A total of 407 participants, who were considered cognitively normal or diagnosed with mild cognitive impairment (MCI) at baseline, were followed longitudinally over an average 4.1 years (range=0.8-9.2 years). Informant-based ratings from the Everyday Cognition (ECog; Farias et al., 2008) and the Instrumental Activities of Daily Living (Lawton & Brody, 1969) scales assessed the degree of functional limitations and incident IADL disability, respectively. Cox proportional hazards models revealed that more severe functional limitations (as measured by the Total ECog score) at baseline were associated with approximately a four-fold increased risk of developing IADL disability a few years later. Among the ECog domains, functional limitations in Everyday Planning, Everyday Memory, and Everyday Visuospatial domains were associated with the greatest risk of incident functional disability. These results remained robust even after controlling for participants' neuropsychological functioning on tests of executive functions and episodic memory. Current findings indicate that early functional limitations have prognostic value in identifying older adults at risk for developing functional disability. Findings highlight the importance of developing interventions to support everyday abilities related to memory, executive function, and visuospatial skills in an effort to delay loss of independence in IADLs.

Social participation and the prevention of functional disability in older Japanese: the JAGES cohort study.

BackgroundWe examined the relationship between incident functional disability and social participation from the perspective of number of types of organizations participated in and type of social participation in a prospective cohort study.MethodThe study was based on the Aichi Gerontological Evaluation Study (AGES) Cohort Study data. We followed 13,310 individuals aged 65 years or older for 4 years. Analysis was carried out on 12,951 subjects, excluding 359 people whose information on age or sex was missing. Social participation was categorized into 8 types.ResultsCompared to those that did not participate in any organizations, the hazard ratio (HR) was 0.83 (95% CI: 0.73–0.95) for participation in one, 0.72 (0.61–0.85) for participation in two, and 0.57 (0.46–0.70) for participation in three or more different types of organizations. In multivariable adjusted models, participation in the following types of organization was protective for incident disability: local community organizations (HR = 0.85, 95% CI: 0.76–0.96), hobby organizations (HR = 0.75, 95% CI: 0.64–0.87), and sports organizations (HR = 0.64, 95% CI: 0.54–0.81).ConclusionSocial participation may decrease the risk of incident functional disability in older people in Japan. This effect may be strengthened by participation in a variety of different types of organizations. Participating in a local community, hobby, or sports group or organization may be especially effective for decreasing the risk of disability.

Relationships between changes in time spent walking since middle age and incident functional disability

ObjectiveTo examine the relationship between changes in time spent walking since middle age and incident functional disability. MethodIn 2006, we conducted a prospective cohort study of 7177 disability-free Japanese individuals aged ≥65years who lived in Ohsaki City, Miyagi Prefecture, Japan. Participants were categorized into four groups according to changes in time spent walking based on two questionnaire surveys conducted in 1994 and in 2006. Incident functional disability was retrieved from the public Long-term Care Insurance database, and the subjects were followed up for 5years. The Cox proportional hazards model was used to investigate the association between changes in time spent walking and the risk of incident functional disability. ResultsCompared with subjects who remained sedentary, the multivariate-adjusted hazard ratios (95% confidence intervals) were 0.69 (0.49–0.98) among those who became active and 0.64 (0.50–0.82) among those who remained active. These results did not alter when analyses were stratified by gender, age and motor function status. ConclusionAn increase in time spent walking among sedentary adults is significantly associated with a lower risk of incident functional disability.

Dietary Patterns and Incident Functional Disability in Elderly Japanese: The Ohsaki Cohort 2006 Study

To date, little is known about the association between dietary pattern and disability in older adults. The present prospective cohort study investigated the association between dietary patterns and incident functional disability. Information on food consumption and other lifestyle factors was collected from Japanese older persons aged ≥65 years via a questionnaire. Three dietary patterns (Japanese pattern, animal food pattern, and high dairy pattern) were derived using principal component analysis of the consumption of 39 food and beverage items. Data on functional disability were retrieved from the public Long-term Care Insurance database, in which participants were followed up for 5 years. The Cox model was used to estimate the multivariate-adjusted hazard ratios of incident functional disability. Among 14,260 participants, the 5-year incidence of functional disability was 16.6%. The Japanese pattern score was associated with a lower risk of incident functional disability (hazard ratio of the highest quartile vs the lowest, 0.77; 95% confidence interval: 0.68-0.88; p trend <.001). An animal food pattern and a high dairy pattern tended to have a higher risk of incident functional disability, but not to a significant degree. In Japanese older persons, the Japanese dietary pattern is associated with a decreased risk of incident functional disability.

Green tea consumption and the risk of incident functional disability in elderly Japanese: the Ohsaki Cohort 2006 Study

Background: Previous studies have reported that green tea consumption is associated with a lower risk of diseases that cause functional disability, such as stroke, cognitive impairment, and osteoporosis. Although it is expected that green tea consumption would lower the risk of incident functional disability, this has never been investigated directly.Objective: The objective was to determine the association between green tea consumption and incident functional disability in elderly individuals.Design: We conducted a prospective cohort study in 13,988 Japanese individuals aged ≥65 y. Information on daily green tea consumption and other lifestyle factors was collected via questionnaire in 2006. Data on functional disability were retrieved from the public Long-term Care Insurance database, in which subjects were followed up for 3 y. We used Cox proportional hazards regression analysis to investigate the association between green tea consumption and functional disability.Results: The 3-y incidence of functional disability was 9.4% (1316 cases). The multiple-adjusted HR (95% CI) of incident functional disability was 0.90 (0.77, 1.06) among respondents who consumed 1–2 cups green tea/d, 0.75 (0.64, 0.88) for those who consumed 3–4 cups/d, and 0.67 (0.57, 0.79) for those who consumed ≥5 cups/d in comparison with those who consumed <1 cup/d (P-trend < 0.001).Conclusion: Green tea consumption is significantly associated with a lower risk of incident functional disability, even after adjustment for possible confounding factors.