Neighborhood environment and muscle mass and function among rural older adults: a 3-year longitudinal study

Neighbourhood walkability and greenspace and their associations with health-related fitness in urban dwelling Canadian adults

OBJECTIVE

Muscular strength and body composition are important components of health-related fitness (HRF). Grip strength and body fat percent, in particular, are associated with chronic disease and affected by health behaviours. Evidence suggests relationships between the neighbourhood built environment (BE) and HRF exist, however, few studies have focused on grip strength and body fat percent. Therefore, our study aimed to estimate the sex-specific associations between the neighbourhood BE, grip strength, and body fat percent among urban-dwelling Canadian adults.

METHODS

We analyzed cross-sectional survey and HRF data collected in 2011-2015 from 4052 males and 7841 females (Alberta's Tomorrow Project, Canada). Grip strength and body fat percent were measured via handgrip dynamometry and bioelectrical impedance analysis, respectively. Walkability (Canadian Active Living Index) and greenness (Normalized Difference Vegetation Index) estimates were linked to participant data. Sex-stratified covariate-adjusted linear regression models estimated the associations between the BE and HRF variables.

RESULTS

Walkability was negatively associated with grip strength and body fat percent in males (β -0.21, 95%CI: -0.31 to -0.11 and β -0.08, 95%CI: -0.15 to -0.02, respectively) and females (β -0.06, 95%CI: -0.10 to -0.01 and β -0.08, 95%CI: -0.14 to -0.02, respectively). Greenness was positively associated with grip strength in males (β 6.99, 95%CI: 3.62 to 10.36) and females (β 2.72, 95%CI: 1.22 to 4.22) but not with body fat percent. Controlling for physical activity and sitting did not attenuate these associations.

CONCLUSION

Characteristics of the neighbourhood BE appear to be associated with muscular strength and body composition, independent of physical activity and sedentary behaviour.

Urban-rural differences in the prevalence and associated factors of sarcopenia: A systematic review and meta-analysis

BACKGROUND

Loss of muscle mass, muscle strength, and/or physical performance due to aging is known as sarcopenia. Regardless of how serious this illness is, no single diagnostic criteria have been established. Much research conducted recently has demonstrated differences between built environment characteristics (i.e., urban and rural) and the occurrence of sarcopenia; however, variations in sarcopenia prevalence in urban-rural areas around the world have been reported by fewer studies. This work sought to determine how sarcopenia prevalence varied between urban and rural areas and to explore the associated influencing factors.

METHODS

Using the pertinent MESH phrases and free words, PubMed, Web of Science, Embase, and China national knowledge infrastructure databases were scanned for core sarcopenia literature up to February 26, 2023. Observational studies involving urban-rural patients with sarcopenia published in Chinese and English, and assessing muscle mass via computed tomography, bioelectrical impedance, or dual-energy X-ray absorption techniques were considered as inclusion criteria. The meta-analysis involved analysis of the urban-rural prevalence in subgroups by diagnostic criteria, tools for assessing muscle mass and study type, as well as the factors related to urban-rural differences in the occurrence of sarcopenia. STATA version 11.0 was used to perform the statistical analysis.

RESULTS

Sixty-six articles involving 433,091 participants were included for analysis: of which 27 were analyzed for both prevalence and related factors whereas 39 were for only prevalence. The meta-analysis revealed the prevalence of sarcopenia to be 0.18 (95 % CI 0.14-0.22), with significant heterogeneity (P < 0.001; I2 = 99.9 %). Moreover, the prevalence of sarcopenia in urban group [0.16 (I2 = 99.9 %, 95 % CI 0.1-0.22)] was lower than in rural group [0.2 (I2 = 99.6 %, 95 % CI 0.16-0.25)] and urban-rural group [0.21 (I2 = 97.5 %, 95 % CI 0.16-0.25)]. Besides, the factors significantly associated with sarcopenia in urban-rural areas were age, gender, BMI, malnutrition, physical activity, and polypharmacy. There was significant heterogeneity between these factors and the association of sarcopenia.

CONCLUSIONS

Sarcopenia is associated with aspects of the built environment, and studies have revealed that sarcopenia is more common in rural than in urban populations with influencing factors including age, gender, BMI, poor nutrition, insufficient physical activity, and polypharmacy. The lack of uniform diagnostic criteria makes a robust and comprehensive assessment difficult. Therefore, the formation of certain universal and standardized diagnostic criteria will help future research on sarcopenia.

Review: myogenic and muscle toxicity targets of environmental methylmercury exposure

A number of environmental toxicants are noted for their activity that leads to declined motor function. However, the role of muscle as a proximal toxicity target organ for environmental agents has received considerably less attention than the toxicity targets in the nervous system. Nonetheless, the effects of conventional neurotoxicants on processes of myogenesis and muscle maintenance are beginning to resolve a concerted role of muscle as a susceptible toxicity target. A large body of evidence from epidemiological, animal, and in vitro studies has established that methylmercury (MeHg) is a potent developmental toxicant, with the nervous system being a preferred target. Despite its well-recognized status as a neurotoxicant, there is accumulating evidence that MeHg also targets muscle and neuromuscular development as well as contributes to the etiology of motor defects with prenatal MeHg exposure. Here, we summarize evidence for targets of MeHg in the morphogenesis and maintenance of skeletal muscle that reveal effects on MeHg distribution, myogenesis, myotube formation, myotendinous junction formation, neuromuscular junction formation, and satellite cell-mediated muscle repair. We briefly recapitulate the molecular and cellular mechanisms of skeletal muscle development and highlight the pragmatic role of alternative model organisms, Drosophila and zebrafish, in delineating the molecular underpinnings of muscle development and MeHg-mediated myotoxicity. Finally, we discuss how toxicity targets in muscle development may inform the developmental origins of health and disease theory to explain the etiology of environmentally induced adult motor deficits and accelerated decline in muscle fitness with aging.

Mediation analysis of the associations between neighbourhood walkability and greenness, accelerometer-measured physical activity, and health-related fitness in urban dwelling Canadians

OBJECTIVE

To estimate sex-specific associations (total, direct, and indirect effects) between objectively measured neighbourhood walkability and greenness and objectively measured physical activity and health-related fitness including cardiorespiratory and muscular fitness in Canadian adults.

METHODS

Neighbourhood walkability (Canadian Active Living Environment) and greenness (Normalized Difference Vegetation Index; NDVI) data were linked to cardiorespiratory (i.e., submaximal step test estimated V̇O2 max) and muscular fitness (i.e., handgrip strength) and accelerometer measured physical activity; Canadian Health Measures Survey). Covariate-adjusted sex-stratified path analyses was conducted to assess if physical activity (light: LPA; moderate: MPA, and; vigorous: VPA) mediated the associations between neighbourhood walkability, NDVI and health-related fitness. Model sample sizes ranged from 987 to 2796 for males and 989 to 2835 for females.

RESULTS

Among males, we found indirect effects between neighbourhood walkability and cardiorespiratory fitness via LPA (negative) and VPA (positive). We also found a total effect (negative) between neighbourhood walkability and grip strength and indirect effects between neighbourhood walkability and handgrip strength via LPA (negative) and MPA (negative). Among females, we found a total effect (positive) and direct effect (positive) between neighbourhood walkability and cardiorespiratory fitness, and an indirect effect for neighbourhood walkability and cardiorespiratory fitness via LPA. We found no significant effects related to neighbourhood greenness.

CONCLUSIONS

Residing in a neighbourhood with higher walkability may positively affect cardiorespiratory fitness but negatively affect muscular strength. The negative associations between neighbourhood walkability and LPA may offset potential positive associations between neighbourhood walkability and MPA and VPA and their subsequent influence on health-related fitness.

Machine Learning for Sarcopenia Prediction in the Elderly Using Socioeconomic, Infrastructure, and Quality-of-Life Data

Since the WHO's 2021 aging redefinition emphasizes "healthy aging" by focusing on the elderly's ability to perform daily activities, sarcopenia, which is defined as the loss of skeletal muscle mass, is now becoming a critical health concern, especially in South Korea with a rapidly aging population. Therefore, we develop a prediction model for sarcopenia by using machine learning (ML) techniques based on the Korea National Health and Nutrition Examination Survey (KNHANES) data 2008-2011, in which we focus on the role of socioeconomic status (SES), social infrastructure, and quality of life (QoL) in the prevalence of sarcopenia. We successfully identify sarcopenia with approximately 80% accuracy by using random forest (RF) and LightGBM (LGB), CatBoost (CAT), and a deep neural network (DNN). For prediction reliability, we achieve area under curve (AUC) values of 0.831, 0.868, and 0.773 for both genders, males, and females, respectively. Especially when using only male data, all the models consistently exhibit better performance overall. Furthermore, using the SHapley Additive exPlanations (SHAP) analysis, we find several common key features, which mainly contribute to model building. These include SES features, such as monthly household income, housing type, marriage status, and social infrastructure accessibility. Furthermore, the causal relationships of household income, per capita neighborhood sports facility area, and life satisfaction are analyzed to establish an effective prediction model for sarcopenia management in an aging population.

The neighbourhood built environment and health-related fitness: a narrative systematic review

Background

There is increasing evidence demonstrating the importance of the neighbourhood built environment in supporting physical activity. Physical activity provides numerous health benefits including improvements in health-related fitness (i.e., muscular, cardiorespiratory, motor, and morphological fitness). Emerging evidence also suggests that the neighbourhood built environment is associated with health-related fitness. Our aim was to summarize evidence on the associations between the neighbourhood built environment and components of health-related fitness in adults.

Methods

We undertook a systematic review following PRISMA guidelines. Our data sources included electronic searches in MEDLINE, Embase, CINAHL, Web of Science, SPORTDiscus, Environment Complete, ProQuest Dissertations and Theses, and Transport Research International Documentation from inception to March 2021. Our eligibility criteria consisted of observational and experimental studies estimating associations between the neighbourhood built environment and health-related fitness among healthy adults (age ≥ 18 years). Eligible studies included objective or self-reported measures of the neighbourhood built environment and included either objective or self-reported measures of health-related fitness. Data extraction included study design, sample characteristics, measured neighbourhood built environment characteristics, and measured components of health-related fitness. We used individual Joanna Briggs Institute study checklists based on identified study designs. Our primary outcome measure was components of health-related fitness (muscular; cardiorespiratory; motor, and morphological fitness).

Results

Twenty-seven studies (sample sizes = 28 to 419,562; 2002 to 2020) met the eligibility criteria. Neighbourhood destinations were the most consistent built environment correlate across all components of health-related fitness. The greatest number of significant associations was found between the neighbourhood built environment and morphological fitness while the lowest number of associations was found for motor fitness. The neighbourhood built environment was consistently associated with health-related fitness in studies that adjusted for physical activity.

Conclusion

The neighbourhood built environment is associated with health-related fitness in adults and these associations may be independent of physical activity. Longitudinal studies that adjust for physical activity (including resistance training) and sedentary behaviour, and residential self-selection are needed to obtain rigorous causal evidence for the link between the neighbourhood built environment and health-related fitness.

Trial registration

Protocol registration: PROSPERO number CRD42020179807.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01359-0.

The Effects of Neighborhood Physical and Social Environment on Physical Function among Japanese Community-Dwelling Older Adults: A One-Year Longitudinal Study

Previous studies have shown a relationship between physical and social aspects of the neighborhood environment (e.g., built environment, safety) and physical function in older adults. However, these associations are unclear in older Asian adults because longitudinal studies are lacking. This study examined the effects of neighborhood physical and social environment on longitudinal changes in physical function among Japanese older adults. We analyzed 299 Japanese community-dwelling adults aged ≥65 years. Neighborhood environment was assessed using the International Physical Activity Questionnaire Environment Module. Physical function was assessed using handgrip strength, knee extension muscle strength, 5-m walking time, and a timed up-and-go test (TUG) in baseline and follow-up surveys. Changes in physical function over one year were calculated and classified into decline or maintenance groups based on minimal detectable changes. Multiple logistic regression analysis showed that even after adjusting for confounding factors, good access to recreational facilities affected the maintenance of 5-m walking time (odds ratio [OR] = 2.31, 95% confidence interval [CI]: 1.02–5.21) and good crime safety affected the maintenance of TUG (OR = 1.87, 95%CI: 1.06–3.33). Therefore, it is important to assess both physical and social environmental neighborhood resources in predicting decline in physical function among Japanese older adults.

Car Driving Status and Living Arrangement Associated with Sarcopenia among Rural Japanese Older Adults: A Cross-Sectional Study

Ensuring mobility after driving cessation is an important public health issue to prevent functional limitations, but this issue is still not fully understood in rural settings. The aim of this study was to test the hypothesis that being a non-driver and living alone is associated with a greater risk of sarcopenia among the community-dwelling elderly in rural Japanese areas. This study was conducted in 2018 and data from 738 participants were used. Sarcopenia was assessed by measuring walking speed, handgrip strength, and skeletal muscle mass. Car driving status and living arrangement were collected using self-reported questionnaires and face-to-face interviews. Four groups were set to determine combined conditions of car driving status and living arrangement. Logistic regression analysis was performed to estimate the odds ratio (OR) and a 95% confidence interval of sarcopenia after adjustment for confounding factors. Compared with the reference group (driver and living with others), the OR of sarcopenia was significantly higher in the non-driver and living alone group (OR = 2.21; 95% confidence interval, 1.02–4.80). Our findings suggest that the consideration of both driving status and living arrangement are important in the formulation of public health strategies to prevent sarcopenia in rural Japanese areas.

Association between a hilly neighborhood environment and falls among rural older adults: a cross-sectional study

Objective: Falls in older adults are a major public health issue, and it is unclear whether the neighborhood environment is associated with falls among this group. This cross-sectional study investigated whether hilly neighborhood environmental factors were associated with fall status (falls or fear of falling) in rural Japanese older adults.

Materials and Methods: Data obtained from 965 participants aged 65 years and older living in Unnan City, Shimane Prefecture, Japan, in 2017 were analyzed. Fall status was assessed based on the 1-year fall incidence (yes/no) for the past year and fear of falling (yes/no) using a self-report questionnaire. For hilly neighborhood environmental factors, the mean elevation and land slope were assessed using a geographic information system. The logistic regression model examined the odds ratios (OR) and 95% confidence intervals (CIs) of fall status in quartiles for elevation and land slope, respectively, and was adjusted for confounders.

Results: Falls and fear of falling were observed in 16.8% and 43.2% of participants, respectively. Falls were associated with elevation (OR 1.99, 95% CI 1.17–3.37 for Q2 vs. Q1; OR 2.02, 95% CI 1.19–3.44 for Q3 vs. Q1) and land slope (OR 1.74, 95% CI 1.04–2.93 for Q3 vs. Q1; OR 1.74, 95% CI 1.04–2.93 for Q4 vs. Q1). Fear of falling was associated with elevation (OR 1.78, 95% CI 1.19–2.65 for Q3 vs. Q1) and land slope (OR 1.51, 95% CI 1.01–2.25 for Q4 vs. Q1).

Conclusion: Our study found that elevation and land slope as hilly neighborhood environment factors were positively associated with falls or fear of falling among older adults living in rural Japan. Prospective observational studies that investigate the effects of region-specific environmental factors on falls among older adults should be conducted.

Perceived Neighborhood Environment Associated with Sarcopenia in Urban-Dwelling Older Adults: The Korean Frailty and Aging Cohort Study (KFACS)

Sarcopenia is associated with adverse health outcomes among older individuals. However, little is known about its association with neighborhood environmental factors. We explored the relationship between sarcopenia and perceived neighborhood environmental factors among community-dwelling older adults aged 70-84 years. We analyzed 1778 participants (mean age of 75.9 ± 3.8 years; 54.0% women) who lived in urban areas and underwent dual-energy X-ray absorptiometry from the Korean Frailty and Aging Cohort Study. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 definition. Perceived neighborhood environmental factors were assessed using the Environmental Module of the International Physical Activity Questionnaire (IPAQ-E). In the multivariate analysis, compared to the fifth quintile of the IPAQ-E score, the odds ratios (ORs) and 95% confidence intervals (CIs) for sarcopenia in the first, second, third, and fourth quintiles were 2.13 (1.40-3.24), 1.72 (1.12-2.64), 1.75 (1.15-2.66), and 1.62 (1.06-2.47), respectively. These neighborhood environmental characteristics were linked with an increased likelihood of sarcopenia: no public transportation access (OR = 2.04; 95% CI = 1.19-3.48), poor recreational facilities access (OR = 1.39; 95% CI = 1.01-1.90), absence of destination (OR = 1.53; 95% CI = 1.06-2.20), many hill hazards (OR = 1.36; 95% CI = 1.03-1.78), and lack of traffic safety (OR = 1.35; 95% CI = 1.02-1.78). Thus, better neighborhood environmental strategies may help prevent sarcopenia among urban-dwelling older adults.