Clustering of Domain-Specific Sedentary Behaviors and Their Association With Physical Function Among Community-Dwelling Older Adults

Impact of subjective well-being on physical frailty in middle-aged and elderly Japanese with high social isolation

Social isolation exacerbates physical frailty and is associated with subjective well-being. Even those with high levels of social isolation may have different health statuses depending on the type of isolation and their subjective well-being. However, the effect of subjective well-being on the relationship between social isolation and physical frailty remains unclear. This study examined whether the risk of physical frailty was the same for individuals with social isolation according to high and low subjective well-being. The study participants included 1,953 middle-aged Japanese adults aged 45 years and older. Physical frailty was assessed using a modified version of the Fried phenotype criteria. Probabilistic Latent Semantic Analysis was used to classify participants according to social isolation indicators. Subsequently, we focused on the groups with high social isolation and classified them according to whether their subjective well-being was high or low. Subjective well-being was evaluated using the Shiawase and Ikigai scales, which are concepts used in Japan. Finally, we used survival time analysis to examine the relationship between Shiawase or Ikigai and physical frailty in groups with high social isolation. The participants were classified into four groups based on their social isolation status. The physical frailty rate of the high social isolation class was 37.0%, which was significantly higher than that of the other classes. Survival time analysis revealed that among people with high social isolation, those with high Shiawase and Ikigai had a significantly lower risk of physical frailty than those with low Shiawase and Ikigai. All individuals with high social isolation are not at a high risk of physical frailty. The findings reveal that even those with high level of social isolation may have a lower risk of physical frailty if their subjective well-being is high. These results will contribute to promoting the prevention of frailty in middle-aged and older adults.

Validation of an Algorithm for Measurement of Sedentary Behaviour in Community-Dwelling Older Adults

Accurate measurement of sedentary behaviour in older adults is informative and relevant. Yet, activities such as sitting are not accurately distinguished from non-sedentary activities (e.g., upright activities), especially in real-world conditions. This study examines the accuracy of a novel algorithm to identify sitting, lying, and upright activities in community-dwelling older people in real-world conditions. Eighteen older adults wore a single triaxial accelerometer with an onboard triaxial gyroscope on their lower back and performed a range of scripted and non-scripted activities in their homes/retirement villages whilst being videoed. A novel algorithm was developed to identify sitting, lying, and upright activities. The algorithm's sensitivity, specificity, positive predictive value, and negative predictive value for identifying scripted sitting activities ranged from 76.9% to 94.8%. For scripted lying activities: 70.4% to 95.7%. For scripted upright activities: 75.9% to 93.1%. For non-scripted sitting activities: 92.3% to 99.5%. No non-scripted lying activities were captured. For non-scripted upright activities: 94.3% to 99.5%. The algorithm could, at worst, overestimate or underestimate sedentary behaviour bouts by ±40 s, which is within a 5% error for sedentary behaviour bouts. These results indicate good to excellent agreement for the novel algorithm, providing a valid measure of sedentary behaviour in community-dwelling older adults.

Biopsychosocial inequality, active lifestyle and chronic health conditions: a cross-sectional National Health Survey 2013 in Brazil

This study estimated the biopsychosocial factors related to active physical behavior in the Brazilian population with and without chronic non-transmissible disease (NCD). Cross-sectional study of the National Health Survey (NHS) in Brazil, with 60,202 individuals in 2013. Participants were randomly selected by complex sampling. The outcome was physically active behavior measured by performing a minimum of 150 min of physical exercise per week. The independent variables were social and psychological characteristics, lifestyle and health. Cox regression was applied to estimate the prevalence ratio (PR). There are 29,666 (48.3%; 95% CI 47.0–50.0) participants reported having NCD. Not being a smoker or alcoholic, living in an urban area (PR = 1.44; CI95% 1.23–1.68/PR = 1.38; CI95% 1.08–1.75), having informal social support (PR = 1.26; CI95% 1.10–1.44/PR = 1.19; CI95% 1.05–1.34), A social class (PR = 0.43; CI95% 0.25–0.73/PR = 0.46; CI95% 0.26–0.80), high schooling (PR = 0.34; CI95% 0.23–0.51/PR = 0.33; CI95% 0.24–0.46) as well as paid work (PR = 0.87; CI95% 0.78–0.96/PR = 0.89; CI95% 0.79–0.99) are more associated with active lifestyle in both groups. However, only in the group without NCD, the male sex (PR = 1.42; CI95% 1.28–1.57), no having some disability (PR = 1.31; CI95% 1.03–1.66) and having private health insurance (PR = 1.26; CI95% 1.13–1.41) were more associated with active behavior, while in the group with NCD, being elderly (PR = 1.22; CI95% 1.05–1.42), not be white (PR = 0.85; CI95% 0.77–0.95) and not having restful sleep (PR = 1.23; CI95% 1.08–1.40) are associated with active lifestyle. People with and without NCD in Brazil have very close active behavior, however, some biopsychosocial factors such as: sex, age, lifestyle, socioeconomic level are unevenly associated with the active lifestyle in the groups. Thus, therapeutic or preventive proposals as well as public policies for health promotion must observe these distinctions when elaborating their actions.

Identifying typologies of diurnal patterns in desk-based workers' sedentary time

The purpose of this study was to identify typologies of diurnal sedentary behavior patterns and sociodemographic characteristics of desk-based workers. The sedentary time of 229 desk-based workers was measured using accelerometer devices. The within individual diurnal variations in sedentary time was calculated for both workdays and non-workdays. Diurnal variations in sedentary time during each time period (morning, afternoon, and evening) was calculated as the percentage of sedentary time during each time period divided by the percentage of the total sedentary time. A hierarchical cluster analysis (Ward’s method) was used to identify the optimal number of clusters. To refine the initial clusters, a non-hierarchical cluster analysis (k-means method) was performed. Four clusters were identified: stable sedentary cluster (46.7%), off-morning break cluster (26.6%), off-afternoon break cluster (8.3%), and evening sedentary cluster (18.3%). The stable sedentary cluster had the lowest variations in sedentary time throughout the day and the highest amount of total sedentary time. Participants in the off-morning and off-afternoon break clusters had nearly the same sedentary patterns but took short-term breaks during non-workday mornings or afternoons. The evening sedentary cluster had a completely different pattern, with a longer sedentary time during the evening both on workdays and non-workdays. Sociodemographic attributes such as sex, household income, educational attainment, employment status, sleep duration, and residential area, differed significantly between groups. Initiatives to address desk-based workers’ sedentary behavior need to focus not only on the workplace but also on the appropriate timing for reducing excessive sedentary time in non-work contexts depending on the characteristics and diurnal patterns of target subgroups.