Japanese elderly persons walk faster than non-Asian elderly persons: a meta-regression analysis

Step length is associated with comprehensive frailty status in community-dwelling older people

AIM

To examine spatial-temporal gait parameters associated with comprehensive frailty status in community-dwelling, independent older people.

METHODS

This cross-sectional study included 225 older people (≥65 years) living independently in the community. The Kihon Checklist was used to assess comprehensive frailty status, and participants were classified as robust, pre-frailty, or frailty. A sheet-type plantar pressure sensor was used to evaluate the following gait parameters, which were extracted at the usual and fast pace: gait speed, cadence, stride time, step length-to-height ratio (step length/height), step width, stance duration, double-support time, and variability of each gait parameter. Ordinal logistic regression analysis adjusted for confounding factors was performed to determine the association between gait parameters and frailty status. In addition, the ability to discriminate frailty status was evaluated by receiver operating characteristic (ROC) curve analysis for gait parameters that were significantly associated with frailty status.

RESULTS

Frailty status was pre-frailty in 79 (35.1%) and frailty in 30 (13.3%) participants. Ordinal logistic regression analysis showed a significant association of step length/height (%) at both usual and fast pace with frailty status, even after adjustment for confounding factors (usual pace: odds ratio [OR] = 0.93 [95% confidence interval, CI: 0.86-0.99]; fast pace: OR = 0.93 [95% CI: 0.87-0.99]). ROC curve analysis identified step length/height at fast pace in women as the best discriminator between frailty and non-frailty (area under the curve 0.69, cut-off value 43.4%, sensitivity 50%, specificity 82%).

CONCLUSIONS

Step length appears to be a useful gait parameter for discriminating frailty status in community-dwelling, independent older people. Geriatr Gerontol Int 2024; 24: 18-24.

Association Between Timed Up-and-Go Test and Future Changes in the Frailty Status in a Longitudinal Study of Japanese Community-Dwelling Older Adults

Purpose

This study aimed to evaluate the relationship between timed up-and-go (TUG) test time and changes in frailty status in a longitudinal cohort study of rural Japanese older adults.

Patients and Methods

This prospective cohort study included 545 community-dwelling older adults. Initial and 2-year follow-up surveys were conducted. We compared the number of the Japanese version of the Cardiovascular Health Study components during the follow-up period and classified the participants into three groups: the favorable change, unchanged as prefrail, and unfavorable change groups. Associations between changes in frailty status and TUG time in the first survey were examined. The predictive ability of the TUG test was determined using the receiver operating characteristic (ROC) curve.

Results

The favorable change group comprised 315 individuals (57.8%), the unchanged as prefrail group 105 (19.2%), and the unfavorable change group 125 (22.9%). TUG time was associated with the favorable and unfavorable changes after adjustment for covariates (OR 0.79, 95% CI 0.68-0.92, P=0.001 and OR 1.27, 95% CI 1.09-1.49, P=0.002). The ROC curve of TUG time as a predictor of unfavorable changes showed an area under the curve of 0.59. A cut-off point of TUG was calculated as 6.3 s with 49.6% sensitivity and 66.0% specificity.

Conclusion

TUG time in the first survey was significantly associated with changes in frailty status 2 years later. However, its predictive value as a stand-alone test is limited and has the potential to predict future changes in the frailty status in older adults in combination with other tests.

Social isolation is associated with future decline of physical performance in community-dwelling older adults: a 1-year longitudinal study

BACKGROUND

Social isolation and decline of physical function, such as muscle strength and physical performance, are known to be associated with deterioration of functional capacity. However, the relationship between social isolation and physical function has not been sufficiently clarified by a longitudinal observational study.

AIMS

The aim of this study was to examine whether social isolation is associated with a future decline in physical function in older people.

METHODS

The participants were 166 community-dwelling older people (aged ≥ 65 years). Social isolation and physical function were assessed using the 6-item Lubben Social Network Scale and handgrip strength, knee extensor strength, usual walking time, and the Timed Up and Go (TUG) test in both the baseline and follow-up surveys. To define the presence or absence of physical function decline over time, we used the minimal detectable change. The associations between social isolation and physical function were analyzed using logistic regression analysis adjusted for confounding factors. Further, to examine the possibility of drop-out bias, inverse probability weighting (IPW) was performed.

RESULTS

The results of the logistic regression analysis adjusted for confounding factors showed social isolation at baseline was significantly associated with future TUG decline (OR 2.88, 95% CI 1.15-7.22). Social isolation was not associated with a decline in other physical functions. Similar results were found in an analysis using IPW.

CONCLUSIONS

Social isolation was an independent risk factor for future TUG decline in community-dwelling older people. Our results indicated that assessment of social isolation may be necessary to assess the risk of physical performance decline.

Association Between Physical Function and Neighborhood Environment in Healthy, Older Adults: An Exploratory Study Using Regression Tree Analysis

The aim of this study was to perform an exploratory investigation of the individual characteristics of older adults that affect the relationships between physical function and neighborhood environment. A total of 624 community-dwelling older adults living independently, aged ≥65 years, participated in this cross-sectional study. Physical function was assessed by muscle strength (grip strength and knee extension strength) and physical performance (5-m walking time and Timed Up and Go Test). The neighborhood environment was assessed using the International Physical Activity Questionnaire Environmental Module. The individual characteristics that affect the association between both were analyzed using multiple regression analysis and Classification and Regression tree (CaRT) analysis. In both older men and women, multiple regression analysis showed that neighborhood environment was significantly associated with physical function. On the other hand, on CaRT analyses, older men ≤80 years of age without low back pain and depressive symptoms and perceived good access to recreational facilities had the shortest 5-m walking time. However, CaRT analyses found no relationship between physical function and neighborhood environment in older women. The relationships between physical function and neighborhood environment may be altered by sex, age, and physical and mental health conditions.

Reference Values and Correlations for Multiple Physical Performance Measures: A Cross-Sectional Study among Independently Mobile Older Men in Japan

Purpose: Japan is one of few countries with a male life expectancy over 80 years. The gap between the healthy life span and the total life expectancy is large, highlighting the importance of maintaining physical performance. The present study aims to establish reference values for multiple physical performance measures among high-functioning oldest-old Japanese men and to investigate the correlations among these measurements to understand how these variables are related. Methods: This study was conducted with 120 Japanese males aged 80 years or older who were able to walk independently. Seven measures of physical performance were assessed: handgrip strength, quadriceps strength, static balance ability (one-legged stance), dynamic balance ability (Functional Reach Test; FRT), walking ability (5-m walking time test), combined movement ability (Timed Up & Go test), and bone quality. Cognitive function was also measured (Mini-Mental State Examination; MMSE). Results: Specific reference values are reported for each physical performance measurement explored in this study. Only six participants were classified as cognitively impaired, and 16 had mild cognitive impairment. There were significant correlations of varying levels among all of the measures of physical performance. Age was significantly correlated with all performance measures except FRT, and there was no correlation between age and MMSE. MMSE was weakly correlated with FRT and unrelated to the other performance measures. Conclusions: The reference ranges can be used by older men who have not yet reached 80 years and their health care providers as physical performance targets to facilitate the maintenance of independent mobility in later life.

Living well in older age: what can we learn from the Japanese experience?

Japan has the most aged population in the world. Not only do people live longer in Japan, they also age better. While the ageing population reflects a success story driven by lifestyle factors and health promotion initiatives, it also results in challenges for policymakers, families and older people. Other countries with ageing population profiles, such as the UK, can learn from the Japanese experience. In this article, the authors focus on the potential of health promotion strategies, social connections and technology to enhance well-being in older age.

Fall-related efficacy is a useful and independent index to detect fall risk in Japanese community-dwelling older people: a 1-year longitudinal study

BACKGROUND

Fall-related efficacy has been found to be associated with both falls and fall risk factors such as physical performance. The aim of the present study was to clarify whether fall-related efficacy is, independent of physical performance and other potential risk factors, associated with future falls in community-dwelling older people.

METHODS

The study participants were 237 Japanese older people aged 65 years and over who were living independently in their community. Fall-related efficacy and physical performance were assessed at baseline using the short version of the Falls Efficacy Scale-International (short FES-I) and 5-m walking time, the Timed Up and Go Test, the 5 Times Sit to Stand Test, and grip strength. Physical performance was then again assessed at 1-year follow-up. The number of falls was obtained every 6 months for 1 year after the baseline survey. Instrumental activities of daily living (IADL), depression, fall history, current medications, medical history, and pain were also investigated as potential confounding factors that have possible associations with falls. The associations between the short FES-I, physical performance, and number of falls were analyzed using Poisson regression analysis adjusted for physical performance and potential confounding factors.

RESULTS

The mean age of the participants (75.9% women) was 71.1 ± 4.6 years, and 92.8% could perform IADL independently. The total numbers of falls and fallers during the 1-year follow-up period were 70 and 42, respectively. On Poisson regression analysis adjusted for walking time and potential confounding factors, independent of physical performance, the short FES-I was found to be significantly associated with number of falls (relative risk = 1.09, p < 0.05). On the other hand, physical performance was not significantly associated with the number of falls.

CONCLUSIONS

The findings of the present study suggest that the short FES-I, independent of physical performance and other potential risk factors, is a useful index to detect fall risk in community-dwelling older people, and that fall-related efficacy is an important factor in terms of fall prevention.

Gait Performance Trajectories and Incident Disabling Dementia Among Community-Dwelling Older Japanese

OBJECTIVES

Initial gait speed is a good predictor of dementia in later life. This prospective study used repeated measures analysis to identify potential gait performance trajectory patterns and to determine whether gait performance trajectory patterns were associated with incident disabling dementia among community-dwelling older Japanese.

DESIGN

A prospective, observational, population-based follow-up study.

SETTING

Japan, 2002 to 2014.

PARTICIPANTS

A total of 1686 adults without dementia (mean [SD] age, 71.2 [5.6] years; women, 56.3%) aged 65 to 90 years participated in annual geriatric health assessments during the period from June 2002 through July 2014. The average number of follow-up assessments was 3.9, and the total number of observations was 6509.

MEASUREMENTS

Gait performance was assessed by measuring gait speed and step length at usual and maximum paces. A review of municipal databases in the Japanese public long-term care insurance system revealed that 196 (11.6%) participants developed disabling dementia through December 2014.

RESULTS

We identified 3 distinct trajectory patterns (high, middle, and low) in gait speed and step length at usual and maximum paces in adults aged 65 to 90 years; these trajectory patterns showed parallel declines among men and women. After adjusting for important confounders, participants in the low trajectory groups for gait speed and step length at usual pace were 3.46 (95% confidence interval 1.88-6.40) and 2.12 (1.29-3.49) times as likely to develop incident disabling dementia, respectively, as those in the high trajectory group. The respective values for low trajectories of gait speed and step length at maximum pace were 2.05 (1.02-4.14) and 2.80 (1.48-5.28), respectively.

CONCLUSIONS

Regardless of baseline level, the 3 major trajectory patterns for gait speed and step length tended to show similar age-related changes in men and women in later life. Individuals with low trajectories for gait speed and step length had a higher dementia risk, which highlights the importance of interventions for improvements in gait performance, even among older adults with low gait performance.