Potential utility of physical function measures to improve the risk prediction of functional disability in community-dwelling older Japanese adults: a prospective study.

BACKGROUND: While gait speed, one-leg standing balance, and handgrip strength have been shown to be independent predictors for functional disability, it is unclear whether such simple measures of physical function contribute to improved risk prediction of functional disability in older adults. METHODS: A total of 1,591 adults aged ≥ 65 years and without functional disability at baseline were followed up for up to 7.9 years. Functional disability was identified using the database of Japan's Long-term Care Insurance System. Maximum gait speed, one-leg standing time, and handgrip strength were measured at baseline. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association of physical function and functional disability incidence. The incremental predictive value of each physical function measure for risk prediction was quantified using the difference in overall C-statistic, category-free net reclassification improvement (NRI), and integrated discrimination improvement (IDI) index. RESULTS: During follow-up (median: 7.8 years), functional disability was identified in 384 participants. All of the physical function measures were inversely associated with the risk of functional disability, independent of potential confounding factors. The multivariable adjusted HRs (95 % CIs) for functional disability per one standard deviation increment of maximum gait speed, one-leg-standing time, and hand grip strength were 0.73 (0.65-0.83), 0.68 (0.59-0.79), and 0.72 (0.59-0.86), respectively. Incorporation of each of maximum gait speed, one-leg-stand time, and hand grip strength into a basic model with other risk factors significantly improved C-statistic from 0.770 (95 % CIs, 0.751-0.794) to 0.778 (0.759-0.803), 0.782 (0.760-0.805), and 0.775 (0.756-0.800), respectively (all p < 0.05). A model including all three measures had the highest C-statistic of 0.787 (0.765-0.810). The improvements in risk prediction were also confirmed by category-free NRI and IDI index. CONCLUSIONS: Adding any of the three measures to a basic model with other known risk factors significantly improved the prediction of functional disability and addition of all three measures provided further improvement of the prediction in older Japanese adults. These data provide robust evidence to support the practical utility of incorporating these simple physical function measures into functional disability risk prediction tools.

Different patterns in age-related morphometric alteration of myelinated fibers and capillaries of the tibial nerve: a longitudinal study in normal rats.

Age-related regression of myelinated fibers in peripheral nerves of the lower limbs is strongly influenced by capillaries and results in balance dysfunction and falls. However, the temporal relationships between alteration patterns of myelinated fibers and capillaries have not yet been clarified. This study aimed to investigate age-related morphological and histological changes of both myelinated fibers and capillaries in peripheral nerves to clarify whether myelinated fibers or capillaries change earlier. Seven male Wistar rats each were randomly selected at 20 weeks (young group), 70 weeks (middle group), and 97 weeks (old group) for histological evaluations. The left and right tibial nerves were removed morphologically and histologically to examine myelinated fibers and capillaries. Axon diameter and myelin thickness were almost unaltered in the middle group compared with the young group but were significantly reduced in the old group when compared with the other two groups. However, the capillary diameter and number of microvascular branch points were substantially reduced in the middle group. The current study demonstrates that myelinated fibers of peripheral nerves show signs of regression in elderly rats, whereas capillaries start to reduce in middle-aged animals. In normal aging of the tibial nerve, capillaries may regress before myelinated fibers.

Study design and baseline characteristics of a population-based prospective cohort study of dementia in Japan: the Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD).

BACKGROUND: The burden of dementia is growing rapidly and has become a medical and social problem in Japan. Prospective cohort studies have been considered an effective methodology to clarify the risk factors and the etiology of dementia. We aimed to perform a large-scale dementia cohort study to elucidate environmental and genetic risk factors for dementia, as well as their interaction. METHODS: The Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD) is a multisite, population-based prospective cohort study of dementia, which was designed to enroll approximately 10,000 community-dwelling residents aged 65 years or older from 8 sites in Japan and to follow them up prospectively for at least 5 years. Baseline exposure data, including lifestyles, medical information, diets, physical activities, blood pressure, cognitive function, blood test, brain magnetic resonance imaging (MRI), and DNA samples, were collected with a pre-specified protocol and standardized measurement methods. The primary outcome was the development of dementia and its subtypes. The diagnosis of dementia was adjudicated by an endpoint adjudication committee using standard criteria and clinical information according to the Diagnostic and Statistical Manual of Mental Disorders, 3rd Revised Edition. For brain MRI, three-dimensional acquisition of T1-weighted images was performed. Individual participant data were pooled for data analyses. RESULTS: The baseline survey was conducted from 2016 to 2018. The follow-up surveys are ongoing. A total of 11,410 individuals aged 65 years or older participated in the study. The mean age was 74.4 years, and 41.9% were male. The prevalence of dementia at baseline was 8.5% in overall participants. However, it was 16.4% among three sites where additional home visit and/or nursing home visit surveys were performed. Approximately two-thirds of dementia cases at baseline were Alzheimer's disease. CONCLUSIONS: The prospective cohort data from the JPSC-AD will provide valuable insights regarding the risk factors and etiology of dementia as well as for the development of predictive models and diagnostic markers for the future onset of dementia. The findings of this study will improve our understanding of dementia and provide helpful information to establish effective preventive strategies for dementia in Japan.

Associations of Objectively Measured Patterns of Sedentary Behavior and Physical Activity with Frailty Status Screened by The Frail Scale in Japanese Community-Dwelling Older Adults.

The objective of this study was to investigate the association between objectively measured patterns of sedentary behavior (SB) and physical activity (PA) and frailty status in Japanese community-dwelling older adults. Data was from 65-75 years older adults from the baseline of Itoshima Frail Study were used. Frailty was assessed using a Japanese version of the FRAIL scale. SB and PA were measured using an accelerometer. Multinomial logistic regression and receiver operating characteristic curve analyses were used to investigate the associations of SB and PA patterns with frailty status. Of the total 819 older adults, half were female (51.8%). The prevalence of robust, pre-frailty and frailty was 60.2%, 27.8%, and 12.0%, respectively. SB variables including total sedentary time, sedentary time in bouts of ≥ 10 min and ≥ 30 min, and mean sedentary bout duration were not associated with frailty status. Except LPA and moderate-to-vigorous physical activity (MVPA) in bouts of < 10 min, PA variables including total MVPA time, MVPA in bouts of ≥ 10 min (bouted MVPA), and steps were significantly associated with lower prevalence of frailty. Area under the curves (AUCs) of total MVPA time, bouted MVPA, and steps were 0.64 (P < 0.001), 0.67 (P < 0.001), and 0.66 (P < 0.001), respectively. The optimal cut-off value of total MVPA time, bouted MVPA, and steps to discriminate between frailty and non-frailty were 43.25 min/day, 9.13 min/day, and 3841 steps/day, respectively. Higher levels of total MVPA time, bouted MVPA, and daily steps were negatively associated with frailty. Lower amounts of bouted MVPA (70 min/week) or steps (4000 steps/day) may be achievable initial targets in older adults for frailty management.

Determinants of cognitive performance and decline in 20 diverse ethno-regional groups: A COSMIC collaboration cohort study.

BACKGROUND: With no effective treatments for cognitive decline or dementia, improving the evidence base for modifiable risk factors is a research priority. This study investigated associations between risk factors and late-life cognitive decline on a global scale, including comparisons between ethno-regional groups. METHODS AND FINDINGS: We harmonized longitudinal data from 20 population-based cohorts from 15 countries over 5 continents, including 48,522 individuals (58.4% women) aged 54-105 (mean = 72.7) years and without dementia at baseline. Studies had 2-15 years of follow-up. The risk factors investigated were age, sex, education, alcohol consumption, anxiety, apolipoprotein E ε4 allele (APOE*4) status, atrial fibrillation, blood pressure and pulse pressure, body mass index, cardiovascular disease, depression, diabetes, self-rated health, high cholesterol, hypertension, peripheral vascular disease, physical activity, smoking, and history of stroke. Associations with risk factors were determined for a global cognitive composite outcome (memory, language, processing speed, and executive functioning tests) and Mini-Mental State Examination score. Individual participant data meta-analyses of multivariable linear mixed model results pooled across cohorts revealed that for at least 1 cognitive outcome, age (B = -0.1, SE = 0.01), APOE*4 carriage (B = -0.31, SE = 0.11), depression (B = -0.11, SE = 0.06), diabetes (B = -0.23, SE = 0.10), current smoking (B = -0.20, SE = 0.08), and history of stroke (B = -0.22, SE = 0.09) were independently associated with poorer cognitive performance (p < 0.05 for all), and higher levels of education (B = 0.12, SE = 0.02) and vigorous physical activity (B = 0.17, SE = 0.06) were associated with better performance (p < 0.01 for both). Age (B = -0.07, SE = 0.01), APOE*4 carriage (B = -0.41, SE = 0.18), and diabetes (B = -0.18, SE = 0.10) were independently associated with faster cognitive decline (p < 0.05 for all). Different effects between Asian people and white people included stronger associations for Asian people between ever smoking and poorer cognition (group by risk factor interaction: B = -0.24, SE = 0.12), and between diabetes and cognitive decline (B = -0.66, SE = 0.27; p < 0.05 for both). Limitations of our study include a loss or distortion of risk factor data with harmonization, and not investigating factors at midlife. CONCLUSIONS: These results suggest that education, smoking, physical activity, diabetes, and stroke are all modifiable factors associated with cognitive decline. If these factors are determined to be causal, controlling them could minimize worldwide levels of cognitive decline. However, any global prevention strategy may need to consider ethno-regional differences.

Patterns and Levels of Sedentary Behavior and Physical Activity in a General Japanese Population: The Hisayama Study.

BACKGROUND: The purpose of this cross-sectional study was to describe the patterns and levels of sedentary time and physical activity (PA) in a general Japanese population. METHODS: A total of 1,740 community-dwelling Japanese adults aged ≥40 years participated in this study. Sedentary time and PA were assessed for 7 consecutive days using a tri-axial accelerometer. Daily patterns and levels of sedentary time and PA were calculated by sex, age group (40-64, 65-74, and ≥75 years), and body mass index (BMI; <25 and ≥25 kg/m2). RESULTS: Participants spent half of their waking time being sedentary, 32.7% of which was accumulated in prolonged bouts ≥30 minutes, versus only 54.4 minutes/day (7% of waking time) as moderate-to-vigorous PA (MVPA) (11.8 minutes/day in bouts ≥10 minutes). In addition to total sedentary time, men had longer prolonged sedentary bouts and fewer breaks per sedentary hour than women. Similar trends were observed in participants aged ≥75 years and those with a higher BMI (≥25 kg/m2) compared to those with a younger age and lower BMI. Moreover, participants aged ≥75 years and those with a higher BMI accumulated fewer MVPA minutes in bouts ≥10 minutes. Only 34.8% of the population met the recommended level of ≥150 minutes/week MVPA in bouts ≥10 minutes. CONCLUSION: Japanese adults accumulated a large proportion of total sedentary time in prolonged bouts but few minutes in sustained bouts of MVPA, and few of them met the current PA guideline.

Age-related cognitive decline and associations with sex, education and apolipoprotein E genotype across ethnocultural groups and geographic regions: a collaborative cohort study.

BACKGROUND: The prevalence of dementia varies around the world, potentially contributed to by international differences in rates of age-related cognitive decline. Our primary goal was to investigate how rates of age-related decline in cognitive test performance varied among international cohort studies of cognitive aging. We also determined the extent to which sex, educational attainment, and apolipoprotein E ε4 allele (APOE*4) carrier status were associated with decline. METHODS AND FINDINGS: We harmonized longitudinal data for 14 cohorts from 12 countries (Australia, Brazil, France, Greece, Hong Kong, Italy, Japan, Singapore, Spain, South Korea, United Kingdom, United States), for a total of 42,170 individuals aged 54-105 y (42% male), including 3.3% with dementia at baseline. The studies began between 1989 and 2011, with all but three ongoing, and each had 2-16 assessment waves (median = 3) and a follow-up duration of 2-15 y. We analyzed standardized Mini-Mental State Examination (MMSE) and memory, processing speed, language, and executive functioning test scores using linear mixed models, adjusted for sex and education, and meta-analytic techniques. Performance on all cognitive measures declined with age, with the most rapid rate of change pooled across cohorts a moderate -0.26 standard deviations per decade (SD/decade) (95% confidence interval [CI] [-0.35, -0.16], p < 0.001) for processing speed. Rates of decline accelerated slightly with age, with executive functioning showing the largest additional rate of decline with every further decade of age (-0.07 SD/decade, 95% CI [-0.10, -0.03], p = 0.002). There was a considerable degree of heterogeneity in the associations across cohorts, including a slightly faster decline (p = 0.021) on the MMSE for Asians (-0.20 SD/decade, 95% CI [-0.28, -0.12], p < 0.001) than for whites (-0.09 SD/decade, 95% CI [-0.16, -0.02], p = 0.009). Males declined on the MMSE at a slightly slower rate than females (difference = 0.023 SD/decade, 95% CI [0.011, 0.035], p < 0.001), and every additional year of education was associated with a rate of decline slightly slower for the MMSE (0.004 SD/decade less, 95% CI [0.002, 0.006], p = 0.001), but slightly faster for language (-0.007 SD/decade more, 95% CI [-0.011, -0.003], p = 0.001). APOE*4 carriers declined slightly more rapidly than non-carriers on most cognitive measures, with processing speed showing the greatest difference (-0.08 SD/decade, 95% CI [-0.15, -0.01], p = 0.019). The same overall pattern of results was found when analyses were repeated with baseline dementia cases excluded. We used only one test to represent cognitive domains, and though a prototypical one, we nevertheless urge caution in generalizing the results to domains rather than viewing them as test-specific associations. This study lacked cohorts from Africa, India, and mainland China. CONCLUSIONS: Cognitive performance declined with age, and more rapidly with increasing age, across samples from diverse ethnocultural groups and geographical regions. Associations varied across cohorts, suggesting that different rates of cognitive decline might contribute to the global variation in dementia prevalence. However, the many similarities and consistent associations with education and APOE genotype indicate a need to explore how international differences in associations with other risk factors such as genetics, cardiovascular health, and lifestyle are involved. Future studies should attempt to use multiple tests for each cognitive domain and feature populations from ethnocultural groups and geographical regions for which we lacked data.

The long-term association between physical activity and risk of dementia in the community: the Hisayama Study.

We investigated the long-term influence of physical activity on the risk of dementia in an elderly Japanese population. A total of 803 community-dwelling elderly Japanese individuals without dementia aged ≥65 years were followed prospectively for 17 years. Physically active status was defined as engaging in exercise at least one or more times per week during leisure time, and participants were divided into an active group and an inactive group by the presence or absence of such physical activity. The risk estimates of physical activity on the development of all-cause dementia and its subtypes were computed using a Cox proportional hazards model. During the follow-up, 291 participants developed all-cause dementia. Of these, 165 had Alzheimer's disease (AD), 93 had vascular dementia (VaD), and 47 had other dementia. Compared with the inactive group, the active group showed significantly lower crude incidence of AD (21.8 vs. 14.2 per 1000 person-years, p = 0.01), but no significant differences were observed for all-cause dementia (35.6 vs. 30.5, p = 0.17), VaD (11.3 vs. 9.8, p = 049), and other dementia (4.6 vs. 7.1, p = 0.15). After adjusting for potential confounders, the relationship between physical activity and risk of AD remained significant (adjusted hazard ratio 0.59, 95% confidence interval 0.41-0.84, p = 0.003). Our findings suggest that physical activity reduces the long-term risk of dementia, especially AD, in the general Japanese population.

Sedentary bout durations and metabolic syndrome among working adults: a prospective cohort study.

BACKGROUND: This study aimed to examine the associations between time spent in prolonged and non-prolonged sedentary bouts and the development of metabolic syndrome. METHODS: We used data from a prospective study of Japanese workers. Baseline examination was conducted between 2010 and 2011. A total of 430 office workers (58 women) aged 40-64 years without metabolic syndrome were followed up by annual health checkups until 2014. Metabolic syndrome was defined as having ≥ 3 out of 5 diagnostic criteria from the Joint Interim Statement 2009 definition. Sedentary time was assessed using a tri-axial accelerometer. Time spent in total, prolonged (accumulated ≥ 30 min) and non-prolonged sedentary bouts (accumulated < 30 min) was calculated. Cox proportional hazards models were used to estimate the risk of developing metabolic syndrome. RESULTS: During a median follow-up of 3 years, 83 participants developed metabolic syndrome. After adjustment for age, sex, education, smoking, and family income, positive associations were observed between time spent in prolonged sedentary bouts and the development of metabolic syndrome. After additional adjustment for moderate-to-vigorous physical activity, those in the three highest quartiles of time spent in prolonged sedentary bouts showed higher risk of metabolic syndrome compared to the lowest quartile group, with adjusted hazard ratios (95 % confidence intervals) of 2.72 (1.30 - 5.73), 2.42 (1.11 - 5.50), and 2.85 (1.31 - 6.18), respectively. No associations were seen for time spent in total and non-prolonged sedentary bouts. CONCLUSIONS: Sedentary behavior accumulated in a prolonged manner was associated with an increased risk of metabolic syndrome. In devising public health recommendations for the prevention of metabolic disease, the avoidance of prolonged uninterrupted periods of sedentary behavior should be considered.

Association between participation in social activity and physical fitness in community-dwelling older Japanese adults.

Purpose This study aimed to examine the relationship between participation in social activity and both, composite and individual measures of physical fitness in community-dwelling older adults.Methods This study was conducted using baseline data from the Sasaguri Genkimon Study (SGS), a longitudinal cohort study conducted in 2011. Participants were 1,365 community-dwelling men and women aged 65 years or above, who did not require certified nursing care and who resided in Sasaguri, a town located east of the Fukuoka metropolitan area. Participation in social activity was assessed by asking participants whether they engaged in any of eight social activities. Physical fitness tests assessed participants' handgrip strength and knee extension strength as measures of muscle strength, and their one-leg standing time, 5-m maximum gait speed, and 5-repetition sit-to-stand rate as measures of their physical performance. Multiple linear regression and logistic regression analyses were conducted to assess the relationship between participation in social activity and each measure of physical fitness, adjusting for sex; age; body mass index; socioeconomic status; solitary living; exercise, habitual drinking and smoking; accelerometer-measured, moderate-to-vigorous physical activity; cognitive function; instrumental activities of daily living; distress; social network; and comorbidities.Results A total of 83.6% of the participants were engaged in at least one social activity. After adjusting for potential confounders, engagement in social activity was positively associated with a higher composite physical fitness score, faster gait speed and 5-repetition sit-to-stand rate, and longer one-leg standing time (P=0.008, P=0.030, P=0.034, and P=0.009, respectively).Conclusion Participation in social activity was significantly associated with physical fitness, specifically those related to locomotive function. These associations were independent of various confounders including socioeconomic status, and comorbidities.

Screening for frailty phenotype with objectively-measured physical activity in a west Japanese suburban community: evidence from the Sasaguri Genkimon Study.

BACKGROUND: The low physical activity domain of the frailty phenotype has been assessed with various self-reported questionnaires, which are prone to possible recall bias and a lack of diagnostic accuracy. The primary purpose of this study was to define the low physical activity domain of the frailty phenotype using accelerometer-based measurement and to evaluate the internal construct validity among older community-dwellers. Secondly, we examined potential correlates of frailty in this population. METHODS: We conducted a cross-sectional study of 1,527 community-dwelling older men and women aged 65 and over. Data were drawn from the baseline survey of the Sasaguri Genkimon Study, a cohort study carried out in a west Japanese suburban community. Frailty phenotypes were defined by the following five components: unintentional weight loss, low grip strength, exhaustion, slow gait speed, and low physical activity. Of these criteria, physical activity was objectively measured with a tri-axial accelerometer. To confirm our measure's internal validity, we performed a latent class analysis (LCA) to assess whether the five components could aggregate statistically into a syndrome. We examined the correlates of frailty using multiple stepwise logistic regression models. RESULTS: The estimated prevalence of frailty was 9.3% (95% confidence intervals, CI, 8.4-11.2); 43.9% were pre-frail (95% CI, 41.5-46.4). The percentage of low physical activity was 19.5%. Objectively-assessed physical activity and other components aggregated statistically into a syndrome. Overall, increased age, poorer self-perceived health, depressive and anxiety symptoms, not consuming alcohol, no engagement in social activities, and cognitive impairment were associated with increased odds of frailty status, independent of co-morbidities. CONCLUSIONS: This study confirmed the internal construct validity of the frailty phenotype that defined the low energy expenditure domain with the objective measurement of physical activity. Accelerometry may potentially standardize the measurement of low physical activity and improve the diagnostic accuracy of the frailty phenotype criteria in primary care setting. The potential role of factors associated with frailty merits further studies to explore their clinical application.

Effects of Nitric Oxide Synthase Inhibition on Fiber-Type Composition, Mitochondrial Biogenesis, and SIRT1 Expression in Rat Skeletal Muscle.

It was hypothesized that nitric oxide synthases (NOS) regulated SIRT1 expression and lead to a corresponding changes of contractile and metabolic properties in skeletal muscle. The purpose of the present study was to investigate the influence of long-term inhibition of nitric oxide synthases (NOS) on the fiber-type composition, metabolic regulators such as and silent information regulator of transcription 1 (SIRT1) and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), and components of mitochondrial biogenesis in the soleus and plantaris muscles of rats. Rats were assigned to two groups: control and NOS inhibitor (N (ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME), ingested for 8 weeks in drinking water)-treated groups. The percentage of Type I fibers in the L-NAME group was significantly lower than that in the control group, and the percentage of Type IIA fibers was concomitantly higher in soleus muscle. In plantaris muscle, muscle fiber composition was not altered by L-NAME treatment. L-NAME treatment decreased the cytochrome C protein expression and activity of mitochondrial oxidative enzymes in the plantaris muscle but not in soleus muscle. NOS inhibition reduced the SIRT1 protein expression level in both the soleus and plantaris muscles, whereas it did not affect the PGC-1α protein expression. L-NAME treatment also reduced the glucose transporter 4 protein expression in both muscles. These results suggest that NOS plays a role in maintaining SIRT1 protein expression, muscle fiber composition and components of mitochondrial biogenesis in skeletal muscle. Key pointsNOS inhibition by L-NAME treatment decreased the SIRT1 protein expression in skeletal muscle.NOS inhibition induced the Type I to Type IIA fiber type transformation in soleus muscle.NOS inhibition reduced the components of mitochondrial biogenesis and glucose metabolism in skeletal muscle.

Tri-Axial Accelerometer-Determined Daily Physical Activity and Sedentary Behavior of Suburban Community-Dwelling Older Japanese Adults.

Knowledge regarding accelerometer-derived physical activity (PA) and sedentary behavior (SED) levels is scarce for Japanese older adults. The aims of this study were therefore to 1) describe levels of PA and SED in Japanese community-dwelling older adults, using tri-axial accelerometer; 2) examine the variation of PA and SED with respect to sex, age, and body mass index (BMI). Participants of this study were from the baseline survey of the Sasaguri Genkimon Study, who were 65 years or older and not certified as those requiring long-term care. PA was assessed objectively for seven consecutive days using tri-axial accelerometer. A total of 1,739 participants (median age: 72 years, men: 38.0%) with valid PA data were included. Overall, participants in the present study spent 54.5% of their waking time being sedentary and 45.5% being active, of which 5.4% was moderate-to-vigorous physical activity (MVPA). Women accumulated more minutes of light physical activity (LPA) and MVPA compared with men. In contrast, men spent more time being sedentary. Mean steps per day did not differ between sexes. Furthermore, participants with higher BMI (BMI ≥25) had lower PA levels, and longer SED compared with those with lower BMI (BMI <). PA levels were lower and SED was longer with age. The present study is the first to demonstrate that the levels of PA and SED differed by sex, age, and BMI in Japanese community-dwelling older adults. In particular, women were more active compared with men, providing unique insight into the current level of PA in older adults. Data presented in the study will enable further investigation of additional determinants of PA and SED in order to develop effective population-based intervention strategies to promote PA and reduce prolonged SED in the Japanese population and possibly other rapidly aging societies. Key pointsAccelerometer, that is capable to assess PA more precisely in large scale epidemiological studies, provides opportunity for improving understanding of daily PA in older adults.This study first demonstrated that the levels of PA and SED differed by sex, age, and BMI in Japanese community-dwelling older people.Women were more active compared with men, in terms of more minutes of MVPA.

Identifying associations between sedentary time and cardio-metabolic risk factors in working adults using objective and subjective measures: a cross-sectional analysis.

BACKGROUND: Sedentary behavior has been reported to be associated with metabolic and vascular health independent of moderate-to-vigorous physical activity (MVPA). In order to select appropriate options to measure sedentary behavior in practice and research settings, it is worthwhile to characterize the extent to which objective and subjective measures of sedentary behavior quantify adverse health risks in the same population. This cross-sectional analysis compared accelerometer-derived and self-reported sedentary time to identify their association with cardio-metabolic risk factors. METHODS: Cross-sectional analysis was conducted using data from 661 Japanese workers (145 women) aged 20-64 years. Participants wore a tri-axial accelerometer device for 10 consecutive days and completed the Japan Atherosclerosis Longitudinal Study Physical Activity Questionnaire. Data on body mass index, waist circumference, resting blood pressure, triglycerides, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, total:HDL cholesterol ratio, blood glucose, and glycosylated hemoglobin (HbA1c) were obtained from annual health examinations. RESULTS: Both accelerometer-derived and self-reported sedentary time were deleteriously associated with triglycerides, HDL-cholesterol, total:HDL ratio, and HbA1c after adjustment for potential confounders including MVPA. There were no significant differences in regression coefficients between the two measures. Thus, the magnitude of the associations of both measures with cardio-metabolic risk factors was similar, despite poor agreement between them. Occupational sedentary time was correlated with both measures of total sedentary time, and more consistently associated with cardio-metabolic risk factors than sedentary leisure time. CONCLUSIONS: Both accelerometer and self-report measurements are similarly associated with cardio-metabolic risk factors in a Japanese working adult population. Subjective and objective measures of sedentary behaviors appear to capture different aspects of behaviors. Further efforts to establish data processing methods integrating objective and subjective measures are needed to more effectively assess sedentary time's relationship to health outcomes.

[Prevention programs of risk factors for falls].

Approximately 17% of Japanese older people fall for a year. The femoral neck fractures with falls caused by various functional problems make them depress remarkably activities of daily living and quality of life. In risk factors for falls in old people, muscle weakness, balance and gait disorders particularly increases to falls. The major results from recent systematic reviews have indicated that interventions of exercise, multifactorial, environmental modification and gradual withdrawal of psychotropic medication in community-dwelling elderly people were effective for preventing falls. Regarding the older people in hospitals and sanatoriums, it appeared that comprehensive multifactorial interventions and vitamin D supplementation could be effective in falls rather than exercises intervention only. However, the short period of the exercise intervention may affect ineffectiveness in preventing falls.

Physical Fitness Measures as Potential Markers of Low Cognitive Function in Japanese Community-Dwelling Older Adults without Apparent Cognitive Problems.

Detecting signs of cognitive impairment as early as possible is one of the most urgent challenges in preventive care of dementia. It has still been unclear whether physical fitness measures can serve as markers of low cognitive function, a sign of cognitive impairment, in older people free from dementia. The aim of the present study was to examine an association between each of five physical fitness measures and global cognition in Japanese community-dwelling older adults without apparent cognitive problems. The baseline research of the Sasaguri Genkimon Study was conducted from May to August 2011 in Sasaguri town, Fukuoka, Japan. Of the 2,629 baseline subjects who were aged 65 years or older and not certified as individuals requiring nursing care by the town, 1,552 participants without apparent cognitive problems (Mini-Mental State Examination score ≥24) were involved in the present study (59.0% of the baseline subjects, median age: 72 years, men: 40.1%). Global cognitive function was measured by the Japanese version of the Montreal Cognitive Assessment. Handgrip strength, leg strength, sit-to-stand rate, gait speed, and one-leg stand time were examined as physical fitness measures. In multiple linear regression analyses, each of the five physical fitness measures was positively associated with the Montreal Cognitive Assessment score after adjusting for age and sex (p < 0.001). These associations were preserved after additional adjustment for years of formal education, body mass index, and other confounding factors (p < 0.001). The present study first demonstrated the associations between multiple aspects of physical fitness and global cognitive function in Japanese community-dwelling older people without apparent cognitive problems. These results suggest that each of the physical fitness measures has a potential as a single marker of low cognitive function in older populations free from dementia and thereby can be useful in community-based preventive care of dementia. Key pointsThere is a great need for identifying lifestyle-related markers which help detect subtle cognitive impairment in the preclinical or earlier phase of dementia.In the present study, each of the five physical fitness measures employed was linearly and positively associated with the Montreal Cognitive Assessment score in the present older adults without apparent cognitive problems, after adjusting for age, sex, education, body mass index, and other confounding factors.The results suggest the potential of each physical fitness measure as a single lifestyle-related marker of low cognitive function in the population, which can be useful in community-based preventive care of dementia.

Normative data for the montreal cognitive assessment in a Japanese community-dwelling older population.

BACKGROUND: Although the Montreal Cognitive Assessment (MoCA) is acknowledged as a promising neuropsychological tool, its normative data for older populations have not been established yet. The purpose of this study was to provide normative data for the MoCA in Japanese community-dwelling older people. METHODS: In a Japanese town, 1,977 participants aged 65 years or older (mean age 73.6 years; male 41.3%) completed MoCA tests. After descriptive and regression analyses, normative data were developed for MoCA scores in the population. RESULTS: The mean MoCA score observed (21.8 points) was lower than that for normal controls (27.4 points) in the original validation study of the MoCA. Additionally, 82.6% of MoCA scores fell below the standard cutoff of 26 points for detecting mild cognitive impairment (MCI). The regression analysis showed that higher age and fewer years of formal education were associated with lower MoCA scores (p < 0.001). Normative data for MoCA scores were presented with respect to age and education. CONCLUSION: This study provided normative data for the MoCA in a Japanese community-dwelling older population. This research also suggests that conventional use of the MoCA as a screening tool for MCI might be problematic in cultures different from that in which the cutoff was developed.

Different circulating brain-derived neurotrophic factor responses to acute exercise between physically active and sedentary subjects.

UNLABELLED: Although circulating brain-derived neurotrophic factor (BDNF) level is affected by both acute and chronic physical activity, the interaction of acute and chronic physical activity was still unclear. In this study, we compared the serum and plasma BDNF responses to maximal and submaximal acute exercises between physically active and sedentary subjects. Eight active and 8 sedentary female subjects participated in the present study. Both groups performed 3 exercise tests with different intensities, i.e. 100% (maximal), 60% (moderate) and 40% (low) of their peak oxygen uptake. In each exercise test, blood samples were taken at the baseline and immediately, 30 and 60 min after the test. The serum BDNF concentration was found to significantly increase immediately after maximal and moderate exercise tests in both groups. In maximal exercise test, the pattern of change in the serum BDNF concentration was different between the groups. While the serum BDNF level for the sedentary group returned to the baseline level during the recovery phase, the BDNF levels for the active group decreased below the baseline level after the maximal exercise test. No group differences were observed in the pattern of plasma BDNF change for all exercise tests. These findings suggest that regular exercise facilitates the utilization of circulating BDNF during and/or after acute exercise with maximal intensity. KEY POINTS: In maximal exercise test, the pattern of change in the serum BDNF concentration was different between the groups.While the serum BDNF level for the sedentary group returned to the baseline level during the recovery phase, the BDNF levels for the active group decreased below the baseline level after the maximal exercise test.No group differences were observed in the pattern of serum BDNF change for moderate or low exercise tests.No group differences were observed in the pattern of plasma BDNF change for all exercise tests.

Short Video Viewing, and Not Sedentary Time, Is Associated with Overweightness/Obesity among Chinese Women.

Previous studies have found that the relationship between sedentary time (ST) and overweightness/obesity is unclear. The association between sedentary behavior and overweightness/obesity may depend on the type of sedentary behavior engaged in. Nowadays, in older Chinese adults, especially females, short video viewing (SVV) is the most popular leisure sedentary behavior. However, the association between SVV and overweightness/obesity remains to be determined. This study aimed to examine the associations between ST and SVV and overweightness/obesity in Chinese community-dwelling older women. A cross-sectional analysis of baseline data from the Physical Activity and Health in Older Women Study was carried out in this study. A total of 1105 older Chinese women aged 60-70 years were included. SVV was estimated using a self-reported questionnaire, and ST was objectively measured using a tri-axial accelerometer. Overweightness/obesity indicators, including body fat ratio (BFR), fat mass (FM), visceral fat mass (VFM), subcutaneous fat mass (SFM), trunk fat mass (TFM), and limb fat mass (LFM), were assessed using multi-frequency bioimpedance analysis. The covariates included socio-demographic data and a range of health-related factors. Multiple linear regression analyses were used to assess the association between ST and SVV and overweightness/obesity. ST was significantly positively associated with all indicators of overweightness/obesity; however, the associations disappeared after adjusting for moderate-to-vigorous-intensity physical activity (MVPA). A higher SVV time was associated with a higher body mass index (BMI) (ß = 0.19, 95% confidence interval (CI): 0.05 to 0.32), BFR (ß = 0.31, 95% CI: 0.07 to 0.56), FM (ß = 0.33, 95% CI: 0.04 to 0.61), VFM (ß = 0.09, 95% CI: 0.01 to 0.16), SFM (ß = 0.24, 95% CI: 0.03 to 0.45), TFM (ß = 0.21, 95% CI: 0.04 to 0.39), and LFM (ß = 0.11, 95% CI: 0.00 to 0.23) in the fully adjusted models. Compared with non-food short videos, short food videos had a greater effect on overweightness/obesity. SVV was an independent risk factor for overweightness/obesity. A reduction in SVV (especially the food category) rather than ST might be an effective way to prevent overweightness/obesity when incorporated in future public health policy formulations.

Nonlinear associations between sleep patterns and sarcopenia risks in older adults.

STUDY OBJECTIVES: Despite considering it as a common geriatric condition, sarcopenia is linked to various behavioral factors that may be changeable. As sleep is one of the important routines in physiological homeostasis, further investigating the underlying relationships of sleep behavior with sarcopenia is urgently needed. We examined the association between sleep parameters (ie, sleep duration, bedtime, wake time, or midsleep time) and sarcopenia risks in older adults, in the total sample and age group subsamples. METHODS: A total of 1,068 older adults in Taiwan were included. Data on bedtime, wake time, and sleep duration were collected through telephone interview. Midsleep time was calculated by the midpoint of bedtime and wake time. Sarcopenia was screened by the SARC-F questionnaire composed of 5 questions (the strength, assistance in walking, rising from a chair, climbing stairs, and falls) as well as higher scores was related to greater risks. Generalized additive models were conducted to examine the nonlinear relationships between sleep parameters and sarcopenia risks. RESULTS: The covariate-adjusted analysis showed that a reverse J-shaped relationship for sleep duration and sarcopenia risk (P < .001) and a significant association for wake time and the SARC-F score (P = .009) in total sample, with considering age-related interaction. No associations were found in the other sleep parameters (bedtime and midsleep time) and sarcopenia in older adults. Similar associations were observed between wake time and the SARC-F score across age groups, while diverse associations of sleep duration with the SARC-F score were found in different age groups. CONCLUSIONS: The sleep pattern is significantly associated with sarcopenia risks in aging adults. Improving inappropriate sleep behaviors in older adults is suggested to prevent a decline in muscle function and promote healthy aging. CITATION: Huang W-C, Lin C-Y, Togo F, et al. Nonlinear associations between sleep patterns and sarcopenia risks in older adults. J Clin Sleep Med. 2022;18(3):731-738.