Predictors of Water Turnover in Older Adults: A Doubly Labeled Water- and Triaxial Accelerometer-Based Study.

BACKGROUND: Water is one of the most essential nutrients for life. The water turnover (WT), total body water (TBW), and total energy expenditure (TEE) can be measured using the doubly labeled water (DLW) method. WT and TBW are lower in older adults than in young adults, and the former are susceptible to dehydration, necessitating to identify predictors of the WT in older adults. OBJECTIVES: The current study aimed to examine the association between WT and physical activity, physical function, and body composition in Japanese adults aged ≥65 y and identify predictors for WT in this population. METHODS: This study enrolled 133 older adults (women, n = 61; men, n = 72) aged 65-88 y. WT, TBW, TEE, fat-free mass (FFM), and percent body fat (%Fat) were determined using the DLW method. The fitness age score (FAS) was obtained from 5 physical fitness tests. Physical activity and the step count were assessed using a previously validated triaxial accelerometer. Multiple regression analyses were performed with WT as the dependent variable. RESULTS: WT was positively associated with weight, physical activity level (PAL), moderate-vigorous physical activity, and TEE, and negatively associated with sedentary behavior. We examined potential predictors for WT using age, sex, height, weight, FFM, %Fat, TEE, PAL, and FAS in older Japanese adults. CONCLUSIONS: Our results confirmed that age, sex, weight, FFM, TEE, and PAL are the potential predictors of WT in older Japanese adults aged ≥65 y.

Isotope Dilution Space Ratio Declines Above the Age of 60 Years, Potentially Impacting Estimates of Total Energy Expenditure by the Doubly Labeled Water Method1-3, *, ˆ.

Doubly labeled water is gold standard for measuring total energy expenditure (TEE). Measurements using the method are sensitive to the isotope dilution space ratio (DSR). Accuracy and precision of the method might be improved if we could identify factors influencing DSR. We evaluated the potential associations of age, sex, ethnicity, anthropometry, body composition, turnover rates of the isotopes, and geographical elevation with DSR. We used univariate regression analysis to explore the relationships between the continuous variables and analysis of variance to test the relationships between the categorical variables with DSR. Subsequently, we used General Linear Modeling (GLM) and One-way ANOVA to evaluate the simultaneous associations of age, sex, ethnicity, fat-free mass (FFM) and fat mass (FM) on DSR. From 5,678 measurements complied from studies around the world with diverse ethnicity and living at various elevations, the average DSR was 1.0364 ± 0.0141 (mean ± SD). No meaningful physiological effect of any of the continuous and categorical variable on DSR was detected. GLM analysis revealed no effect of FFM and FM (P > 0.33) on DSR, but DSR decreased with age (P < 0.001) among those 60 years of age and older regardless of sex. Among the White who were younger than 60 years of age, DSR was not related to FFM and FM (P = 0.73) but was affected by both age and sex (P < 0.001). Previous estimates of age-related decline in TEE may have overestimated TEE at age 90. Validation studies on older participants are required to confirm this finding.

Determinant of factors associated with water requirement measured using the doubly labelled water method among older Japanese adults.

OBJECTIVE: Water is an essential nutrient for all organisms and is important for maintaining life and health. We aimed to develop a biomarker-calibrated equation for predicting water turnover (WT) and pre-formed water (PW) using the doubly labelled water (DLW) method. DESIGN: Cross-sectional study. SETTING: General older population from the Kyoto-Kameoka Study, Japan. PARTICIPANTS: The 141 participants aged ≥ 65 years were divided into a model developing (n 71) and a validation cohort group (n 70) using a random number generation. WT and PW was measured using the DLW method in May-June of 2012. In developing the cohort, equations for predicting WT and PW were developed by multivariate stepwise regression using all data from the questionnaires in the Kyoto-Kameoka study (including factors such as dietary intake and personal characteristics). WT and PW measured using the DLW method were compared with the estimates from the regression equations developed using the Wilcoxon signed-rank test and correlation analysis in validation cohort. RESULTS: The median WT and PW for 141 participants were 2·81 and 2·28 l/d, respectively. In the multivariate model, WT (R2 = 0·652) and PW (R2 = 0·623) were moderately predicted using variables, such as height, weight and fluid intake from beverages based on questionnaire data. WT (r = 0·527) and PW (r = 0·477) predicted that using this model was positively correlated with the values measured by the DLW method. CONCLUSIONS: Our results showed factors associated with water requirement and indicated a methodological approach of calibrating the self-reported dietary intake data using biomarkers of water consumption.

Association between doubly labelled water-calibrated energy intake and objectively measured physical activity with mortality risk in older adults.

BACKGROUND: Physical activity or biomarker-calibrated energy intake (EI) alone is associated with mortality in older adults; the interaction relationship between the combined use of both factors and mortality has not been examined. We evaluated the relationship between mortality and calibrated EI and step counts in older adults. METHODS: This prospective study included 4,159 adults aged ≥65 years who participated in the Kyoto-Kameoka study in Japan and wore a triaxial accelerometer between 1 April and 15 November 2013. The calibrated EI was calculated based on a previously developed equation using EI biomarkers. The step count was obtained from the accelerometer ≥ 4 days. Participants were classified into the following four groups: low EI (LEI)/low step counts (LSC) group (EI: <2,400 kcal/day in men and <1,900 kcal/day in women; steps: <5,000 /day), n = 1,352; high EI (HEI)/LSC group (EI: ≥2,400 kcal/day in men and ≥1,900 kcal/day in women; steps: <5,000 /day), n = 1,586; LEI/high step counts (HSC) group (EI: <2,400 kcal/day in men and < 1,900 kcal/day in women; steps: ≥5,000 /day), n = 471; and HEI/HSC group (EI: ≥2,400 kcal/day in men and ≥1,900 kcal/day in women; steps: ≥5,000 /day), n = 750. Mortality-related data were collected until 30 November 2016. We performed a multivariable Cox proportional hazard analysis. RESULTS: The median follow-up period was 3.38 years (14,046 person-years), and 111 mortalities were recorded. After adjusting for confounders, the HEI/HSC group had the lowest all-cause mortality rate compared to other groups (LEI/LSC: reference; HEI/LSC: hazard ratio [HR]: 0.71, 95% confidence interval [CI]: 0.41-1.23; LEI/HSC: HR: 0.59, 95% CI: 0.29-1.19; and HEI/HSC: HR: 0.10, 95% CI: 0.01-0.76). No significant interaction was observed between the calibrated EI and steps with mortality. The spline model showed that 35-42 kcal/100 steps/day of EI/100 steps was associated with the lowest mortality risk. CONCLUSIONS: HR mortality risk was lowest at 35-42 kcal/100 steps/day, suggesting that very high (≥56 kcal) or low (<28 kcal) EI/100 steps are not inversely associated with mortality. Adherence to optimal EI and adequate physical activity may provide sufficient energy balance to explain the inverse association with mortality among older Japanese adults.

Greater male variability in daily energy expenditure develops through puberty.

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks. We tested this hypothesis on a large dataset by comparing the amount of male variation and female variation in total EE, activity EE and basal EE, at different life stages, along with several morphological traits: height, fat free mass and fat mass. Total EE, and to some degree also activity EE, exhibit considerable greater male variation (GMV) in young adults, and then a decreasing GMV in progressively older individuals. Arguably, basal EE, and also morphometrics, do not exhibit this pattern. These findings suggest that single male sexual characteristics may not exhibit peak GMV in young adulthood, however total and perhaps also activity EE, associated with many morphological and physiological traits combined, do exhibit GMV most prominently during the reproductive life stages.

Combined Use of Sleep Quality and Duration Is More Closely Associated With Mortality Risk Among Older Adults: A Population-based Kyoto-Kameoka Prospective Cohort Study.

BACKGROUND: Whether sleep quality and duration assessed from multiple domains, either individually or in combination, are strongly associated with mortality risk in older adults remains unelucidated. We aimed to clarify these relationships. METHODS: We enrolled 7,668 older (age ≥65 years) Japanese adults in the Kyoto-Kameoka prospective cohort study who provided valid responses to the Pittsburgh Sleep Quality Index (PSQI) in a mail-in survey. Sleep quality and duration were classified into six groups using the previously validated PSQI: short sleep duration (SSD: <360 min/day)/sleep disturbance (SD: ≥5.5 PSQI points), n = 701; SSD/non-sleep disturbance (NSD: <5.5 PSQI points), n = 100; optimal sleep duration (OSD: 360-480 min/day)/NSD, n = 1,863; OSD/SD, n = 2,113; long sleep duration (LSD: >480 min/day)/NSD, n = 1,972; LSD/SD, n = 919. Mortality data were collected from February 15, 2012, to November 30, 2016. We evaluated the relationship between all-cause mortality risk and sleep quality and duration (and their combinations) using a multivariable Cox proportional hazards model that included baseline covariates. RESULTS: The median follow-up period was 4.75 years (34,826 person-years), with a total of 616 deaths. After adjusting for confounders, compared with other groups, SSD/SD and LSD/SD had the highest hazard ratio (HR) of mortality (SSD/SD: HR 1.56; 95% confidence interval [CI], 1.10-2.19; SSD/NSD: HR 1.27; 95% CI, 0.47-3.48; OSD/NSD: reference; OSD/SD: HR 1.20; 95% CI, 0.91-1.59; LSD/NSD: HR 1.35; 95% CI, 1.03-1.77; LSD/SD: HR 1.83; 95% CI, 1.37-2.45). However, mortality risk was not associated with the interaction between sleep quality and duration. CONCLUSION: Older adults with sleep disturbances involving SSD and LSD have a strong positive association with mortality risk, suggesting an additive effect between sleep quality and duration.

Variability in energy expenditure is much greater in males than females.

In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male variation if many of them do not. Sex differences in energy expenditure variation have been little explored. We analyzed a large database on energy expenditure in adult humans (1494 males and 3108 females) to investigate whether humans have evolved sex differences in the degree of interindividual variation in energy expenditure. We found that, even when statistically comparing males and females of the same age, height, and body composition, there is much more variation in total, activity, and basal energy expenditure among males. However, with aging, variation in total energy expenditure decreases, and because this happens more rapidly in males, the magnitude of greater male variation, though still large, is attenuated in older age groups. Considerably greater male variation in both total and activity energy expenditure could be explained by greater male variation in levels of daily activity. The considerably greater male variation in basal energy expenditure is remarkable and may be explained, at least in part, by greater male variation in the size of energy-demanding organs. If energy expenditure is a trait that is of indirect interest to females when choosing a sexual partner, this would suggest that energy expenditure is under sexual selection. However, we present a novel energetics model demonstrating that it is also possible that females have been under stabilizing selection pressure for an intermediate basal energy expenditure to maximize energy available for reproduction.

Influence of ultrasound focus depth on the association between echo intensity and intramuscular adipose tissue.

INTRODUCTION/AIMS: Attenuation of the ultrasound (US) wave is a serious limitation of echo intensity (EI) on B-mode US. The aim of this study was to determine whether the focus depth of US images influences the depth-dependent attenuation of EI and the relationship between EI and intramuscular adipose tissues (IntraMAT). METHODS: The rectus femoris (RF) and vastus intermedius (VI) of the right thigh were studied in 135 adults (92 older, 43 younger). The EI on US images was measured at three focus depth conditions: top of the image, center of the RF, and center of the VI. The depth of the region of interest (ROI) was measured. IntraMAT was calculated using water and fat images based on the two-point Dixon technique with a 3.0-T magnetic resonance imaging scanner. RESULTS: The correlation between EI and IntraMAT was stronger in the focus RF and VI conditions than in the focus top condition and stronger for RF than for VI. The depth of the ROI influenced the IntraMAT-adjusted residual EI more in the focus top condition than in the focus RF and VI conditions, and influenced VI more strongly than it did RF. DISCUSSION: By mitigating EI attenuation, EI with a focus depth adjusted to the ROI reflected IntraMAT more accurately than that without adjustment. However, it may not completely prevent the potential influence of depth-dependent attenuation of EI, especially for deeper muscles such as the VI.

Adherence to the food-based Japanese dietary guidelines and prevalence of poor oral health-related quality of life among older Japanese adults in the Kyoto-Kameoka study.

Although better diet quality is inversely related to the risk of geriatric disorders, the association of adherence to dietary guidelines with oral health-related quality of life (OHRQoL) is unclear. We aimed to investigate this association in older Japanese adults. This cross-sectional study included 7984 Japanese participants aged ≥ 65 years from the population-based Kyoto-Kameoka study. Dietary intake was estimated using a validated self-administered FFQ. The scores for adherence to the Japanese Food Guide Spinning Top (range: 0 (worst) to 80 (best)) were calculated. These scores were stratified into quartiles (Qs). Poor OHRQoL was defined as a score ≤ 50 using a 12-item Geriatric Oral Health Assessment Index. The OR and 95 % CI were calculated using multivariable logistic regression and the spline model. Higher adherence score was associated with a lower prevalence of poor OHRQoL (Q1-Q4:36·0 %, 32·1 %, 27·9 % and 25·1 %, respectively). An inverse association was found between the score for adherence to the food-based Japanese dietary guidelines and the OR of poor OHRQoL among all the participants (Q1: reference; Q2: OR, 0·87 (95 % CI: 0·75, 1·00); Q3: OR, 0·77 (95 % CI: 0·66, 0·90); Q4: OR, 0·72 (95 % CI: 0·62, 0·85); Pfor trend < 0·001). These relationships were similar to the results in the spline model. Higher adherence to the food-based Japanese dietary guidelines is inversely associated with the prevalence of poor OHRQoL in older adults. Our results may provide useful insights to improve and maintain oral health.

Diet quality and physical or comprehensive frailty among older adults.

PURPOSE: While the association between diet quality and mortality has been previously demonstrated, the association between frailty and diet quality has not been evaluated well. This study aimed to investigate the association between diet quality and prevalence of both physical and comprehensive frailty, using two validated tools, in a community-based cohort of older adults. METHODS: We conducted cross-sectional analyses using baseline data of 7022 participants aged ≥ 65 years in the Kyoto-Kameoka study. Diet quality was assessed by calculating the adherence scores to the Japanese Food Guide Spinning Top using a validated questionnaire; the participants were stratified into quartile groups based on these scores. Physical and comprehensive frailty was assessed using the Fried phenotype model-based Frailty Screening Index and the Kihon Checklist, respectively. Multivariable logistic regression and the restricted cubic spline model were used to calculate odds ratios (ORs) and their 95% confidence intervals (CIs) for associations between adherence scores and frailty prevalence. RESULTS: Higher adherence scores signified a higher intake of vitamin C, vegetables, dairy products, and fruits. Physical and comprehensive frailty prevalence was 14.2 and 35.8%, respectively. In a multivariable adjusted model, compared with the bottom adherence score quartile, the top quartile was associated with lower ORs of physical (OR 0.64; 95% CI 0.52-0.80) and comprehensive frailty (OR 0.60; 95% CI 0.51-0.71). These relationships were similar to results in the spline model. CONCLUSIONS: This study shows an inverse dose-response relationship between diet quality and prevalence of both physical and comprehensive frailty in older adults.

Association of the interaction between physical activity and sitting time with mortality in older Japanese adults.

PURPOSE: To examine how physical activity (PA) and sitting time (ST) are associated with mortality in older Japanese adults. METHODOLOGY: We used the data of 10 233 older Japanese adults aged ≥65 years who provided valid responses to the International Physical Activity Questionnaire-Short Form (IPAQ-SF) by a mail survey. Both PA and ST were assessed using the IPAQ-SF. The results were classified into high or low categories using ≥3.0 metabolic equivalent PA (150 min/week) and ST (300 min/day) into the following four groups: High PA (HPA)/Low ST (LST), HPA/High ST (HST), Low PA (LPA)/LST, and LPA/HST. Mortality data were collected from July 30, 2011, to November 30, 2016. We assessed the interaction of PA and ST status with the risk of all-cause mortality using the multivariable Cox proportional-hazards model. RESULTS: A total of 1014 people were recorded to have died during a median follow-up period of 5.3 years (51 553 person-years). After adjustment for confounders, the risk of mortality was higher in the LPA/HST group than in all other groups (HPA/LST: reference; HPA/HST group: hazard ratio [HR] 0.86 (95% confidence interval [CI]: 0.66 to 1.12); LPA/LST group: HR 1.09 (95% CI: 0.88 to 1.35); LPA/HST group: HR 1.36 (95% CI: 1.10 to 1.67); and multiplicative interaction: HR 1.44 (95% CI: 1.07 to 1.94)). CONCLUSIONS: The risk of mortality associated with LPA/HST depends on the level of PA, duration of ST, and their interaction with each other. Our results may be useful in ameliorating the adverse effects leading to mortality in individuals with lower PA, by reducing ST.

Validation of the Kihon Checklist and the frailty screening index for frailty defined by the phenotype model in older Japanese adults.

BACKGROUND: The term "frailty" might appear simple, but the methods used to assess it differ among studies. Consequently, there is inconsistency in the classification of frailty and predictive capacity depending on the frailty assessment method utilised. We aimed to examine the diagnostic accuracy of several screening tools for frailty defined by the phenotype model in older Japanese adults. METHODS: This cross-sectional study included 1,306 older Japanese adults aged ≥ 65 years who underwent physical check-up by cluster random sampling as part of the Kyoto-Kameoka Study in Japan. We evaluated the diagnostic accuracy of several screening instruments for frailty using the revised Japanese version of the Cardiovascular Health Study criteria as the reference standard. These criteria are based on the Fried phenotype model and include five elements: unintentional weight loss, weakness (grip strength), exhaustion, slowness (normal gait speed), and low physical activity. The Kihon Checklist (KCL), frailty screening index (FSI), and self-reported health were evaluated using mailed surveys. We calculated the non-parametric area under the receiver operating characteristic curve (AUC ROC) for several screening tools against the reference standard. RESULTS: The participants' mean (standard deviation) age was 72.8 (5.5) years. The prevalence of frailty based on the Fried phenotype model was 12.2% in women and 10.3% in men. The AUC ROC was 0.861 (95% confidence interval: 0.832-0.889) for KCL, 0.860 (0.831-0.889) for FSI, and 0.668 (0.629-0.707) for self-reported health. The cut-off for identifying frail individuals was ≥ 7 points in the KCL and ≥ 2 points in the FSI. CONCLUSIONS: Our results indicated that the two instruments (KCL and FSI) had sufficient diagnostic accuracy for frailty based on the phenotype model for older Japanese adults. This may be useful for the early detection of frailty in high-risk older adults.

Age- and sex-related differences of muscle cross-sectional area in iliocapsularis: a cross-sectional study.

BACKGROUND: This study aimed to determine in how many individuals the iliocapsularis muscle (IC) could be identified on magnetic resonance imaging (MRI) and whether age and sex are associated with the cross-sectional area (CSA) of the IC. METHODS: Thirty-seven healthy younger adults and 40 healthy older adults were assigned to four groups: 1) 20 younger men; 2) 17 younger women; 3) 20 older men; and 4) 20 older women. The CSAs of the IC, IP, the rectus femoris (RF) and the quadriceps (QUAD) were quantified on an axial MRI. RESULTS: The number of individuals with the identified IC was n = 17 (85.0%) of 20 younger men, n = 15 (88.2%) of 17 younger women, n = 18 (90.0%) of 20 older men, and 19 (95.0%) of 20 older women. Our results showed the main effect of sex, but not age, in the CSA of the IC. The men-groups had larger CSA of the IC than the women-groups; however, no difference in CSA of the IC was found between the younger and older groups. Meanwhile, the main effects of age and sex were found for the IP, RF, and QUAD; thus, younger or men groups have larger CSAs of the three muscles than the older or women groups. The IC muscle can be discriminated in 85% - 95% of healthy individuals. CONCLUSION: Although sex and age are associated with the CSA of lower-limb muscles other than the IC, only sex is associated with the CSA of the IC.

Doubly labelled water-calibration approach attenuates the underestimation of energy intake calculated from self-reported dietary assessment data in Japanese older adults.

OBJECTIVE: Self-reported energy intake (EI) estimation may incur systematic errors that could be attenuated through biomarker calibration. We aimed to confirm whether calibrated EI was comparable to total energy expenditure (TEE) measured using the doubly labelled water (DLW) technique. DESIGN: Cross-sectional study. SETTING: General older population from the Kyoto-Kameoka Study, Japan. PARTICIPANTS: This study included sub- and main cohorts of 72 and 8058 participants aged≥ 65 years, respectively. EI was evaluated using a validated FFQ, and calibrated EI was obtained using a previously developed equation based on the DLW method. TEE was considered representative of true EI and also measured using the DLW method. We used a Wilcoxon signed-rank test and correlation analysis to compare the uncalibrated and calibrated EI with TEE. RESULTS: In the sub-cohort, the median TEE, uncalibrated EI and calibrated EI were 8559 kJ, 7088 kJ and 9269 kJ, respectively. The uncalibrated EI was significantly lower than the TEE (median difference = -1847 kJ; interquartile range (IQR): -2785 to -1096), although the calibrated EI was not (median difference = 463 kJ; IQR: -330 to 1541). The uncalibrated (r = 0·275) and calibrated EI (r = 0·517) significantly correlated with TEE. The reproducibility was higher for calibrated EI (interclass correlation coefficient (ICC) = 0·982) than for uncalibrated EI (ICC = 0·637). Similar findings were observed when stratifying the sample by sex. For medians, uncalibrated EI was lower (about 17 %) than calibrated EI in the main cohort. CONCLUSIONS: Biomarker calibration may improve the accuracy of self-reported dietary intake estimation.

Seasonal Changes in Anthropometric, Physiological, Nutritional, and Performance Factors in Collegiate Rowers.

Iguchi J, Kuzuhara, K, Katai, K, Hojo, T, Fujisawa, Y, Kimura, M, Yanagida, Y, and Yamada, Y. Seasonal changes in anthropometric, physiological, nutritional, and performance factors in collegiate rowers. J Strength Cond Res 34(11): 3225-3231, 2020-Well-controlled seasonal distribution of training intensity seems to be an important variable for endurance athletes' success as competitors and for avoidance of overtraining. The aim of this study was to examine the interrelationships of training distribution, body composition, energy intake/expenditure, and rowing ergometer performance throughout the 2012-2013 season. In this study of 15 collegiate male rowers, most of whom started rowing during their time at the university, we divided the 2012-2013 season (total 37 weeks) into 3 phases (off-season, December to mid-March, 16 weeks; pre-season, late March-April, 5 weeks; and in-season, May-August, 16 weeks) and analyzed the transition of 2,000-m rowing ergometer time, training intensity/volume, body composition (body mass and body fat), and energy intake/expenditure in each phase. There were significant main effects of the training time by the intensities; 2,000-m rowing ergometer time; energy expenditure; and protein, fat, and carbohydrate intake across the seasons (p < 0.05). Two findings were particularly important. First, on-water high-intensity training, especially for inexperienced rowers, may contribute to improvement of 2,000-m rowing ergometer performance. Second, higher intake of carbohydrate, and to a lesser degree, protein, is necessary for optimal training adaptation (e.g., increase of muscle glycogen content), and results in better 2,000-m performance on the rowing ergometer. Also, those findings may be beneficial to the coaches who are interested in designing the well-controlled seasonal training program, which is especially intended to improve the 2,000-m rowing ergometer performance as well as avoidance of overtraining.

[Changes in homebound status and related factors in community-dwelling older adults participating in physical checkups over two years].

Objective　This study aims to identify changes in homebound status and related factors in community-dwelling older adults participating in physical checkups over two years in order to help with prevention and recovery from being homebound.Methods　A survey on needs in the sphere of daily life was conducted in July 2011 among 6,696 independent older adults in 10 regions of Kameoka City (baseline survey). Of the 6,696 adults, 1,379 responded to the survey and participated in a physical checkup held between March and April 2012. These individuals were then invited to a similar checkup again in September 2013. Of these, 638 consenting individuals were administered a questionnaire survey (follow-up survey). In all, 522 subjects responded to both surveys (baseline and follow-up) regarding being homebound. The responses involved basic attributes, state of daily living, state of health, items of the Kihon Checklist, items concerning daily living activities in the baseline survey, and items concerning being homebound in the follow-up survey. The responses were analyzed, and an evaluation of homebound status was conducted based on whether or not one (or both) of the two items of the Kihon Checklist were applicable. The subjects were classified according to the following: 1) whether non-homebound individuals remained non-homebound (non-homebound group) or whether they became homebound (homebound transition group) and 2) whether individuals who became homebound recovered (recovery group) or remained the same (persisting group). After comparing the characteristics of each group, a logistic regression analysis was employed to analyze the factors related to changes in homebound status after two years.Results　Of the 375 non-homebound individuals in the baseline survey, 326 (86.9%) and 49 (13.1%) were classified into non-homebound and homebound transition groups, respectively. Of the 147 subjects who became homebound, 85 (57.8%) and 62 (42.2%) were classified into the recovery and persisting groups, respectively.　Among the factors related to change in homebound status after two years, a low score of social role (OR=0.675, CI=0.458-0.997) was an independent factor for being at risk of becoming homebound (P<0.05). Having no diseases under treatment (OR=14.340, CI=1.345-152.944) and a high intellectual activity score (OR=2.643, CI=1.378-5.069) were independent factors of recovery from being homebound (P<0.05).Conclusion　The results of the two year longitudinal study suggest the need for support for non-homebound older individuals devoid of social roles to prevent homebound status. Additionally, there is a need for support surrounding the reduction in obtaining a disease and maintaining intellectual activity in order to recover from being homebound.

[Physical parameters and physical function in older drivers with driving-related anxiety: the Nakagawa Study].

AIM: This study investigated whether driving-related anxiety was independently associated with physical parameters and physical function in community-dwelling older people. METHODS: Participants were 523 community-dwelling older drivers (353 men and 170 women). Participants self-reported driving-related anxiety when driving in familiar environments, and completed physical assessments: visual impairment, auditory impairment, cerebrovascular disease (CVD), hand grip strength, knee extension strength, timed up and go (TUG), chair stand, one leg standing with open eyes, functional reach, vertical jump, preferred gait speed and maximal gait speed. Participants were divided into a driving-related anxiety group (72.8±5.1 years; 21 men, seven women) and a no-anxiety (non-anxiety) group (70.7±4.7 years; 325 men, 163 women). We examined physical performance differences between the anxiety and non-anxiety groups using analysis of covariance, and investigated the relationship between anxiety, physical function and performance using logistic regression analysis (forward stepwise selection). RESULTS: The driving-related anxiety group was significantly older, with higher rates of visual impairment, auditory impairment, and CVD than the non-anxiety group. The anxiety group exhibited independently poorer TUG and maximal gait speed (P<0.05 for both). Logistic regression analysis revealed significant relationships between anxiety and visual impairment (odds ratio [OR]: 5.6, 95% confidence interval [CI]: 2.5-12.6), auditory impairment (OR: 3.0, 95% CI: 1.3-7.0), TUG (OR: 1.46, 95% CI: 1.1-1.9) and CVD (OR: 3.1, 95% CI: 1.0-9.4) (P<0.05 for all). CONCLUSIONS: Driving-related anxiety was significantly associated with worse physical performance, visual impairment, auditory impairment, and CVD in community-dwelling older drivers.

Light rhythmic exercise with dietary milk fat globule membrane improves physical fitness in an elderly Japanese population: a double-blind randomized placebo-controlled trial.

This study aimed to investigate the efficacy of home-based, light gymnastic exercise plus dietary milk fat globule membrane (MFGM) intake on physical fitness of an elderly Japanese sample in a pilot, double-blind, randomized, placebo-controlled trial. Seventy-one subjects (male, n = 13; female, n = 58) were randomly assigned into two groups: placebo (n = 35 [male, n = 6; female, n = 29]) and MFGM group (n = 36 [male, n = 7; female, n = 29]). The intervention was eight weeks. Subjects ingested either MFGM (1 g/day) or placebo tablets daily and engaged in an exercise program daily. Physical function tests were performed at baseline and after four and eight weeks. Foot tapping and open-close stepping scores significantly increased from baseline to eight weeks in the MFGM group. Study results suggest daily MFGM ingestion might further enhance the effects of light-intensity exercise in healthy elderly people.

Sociodemographic and physical predictors of non-participation in community based physical checkup among older neighbors: a case-control study from the Kyoto-Kameoka longitudinal study, Japan.

BACKGROUND: It is difficult to obtain detailed information on non-participants in physical and health examination checkups in community-based epidemiological studies. We investigated the characteristics of non-participants in a physical and health examination checkup for older adults in a nested study from the Japanese Kyoto-Kameoka Longitudinal Study. METHODS: We approached a total of 4831 people aged ≥65 years in 10 randomly selected intervention regions. Participants responded to a mail-based population survey on needs in the sphere of daily life to encourage participation in a free face-to-face physical checkup examination; 1463 participants (706 men, 757 women) participated in the physical checkup. A multiple logistic regression model was performed to investigate the adjusted odds ratios (aOR) of non-participation based on sociodemographic status apart from psychological and physiological frailty as assessed by the validated Kihon Checklist. RESULTS: There was a significant, inverse relationship between non-participation and frequently spending time alone among individuals who lived with someone or other family structure (aOR = 0.53, standard error [SE] 0.08 in men, aOR = 0.66, SE 0.09 in women). Very elderly (over 80 years old) women, poorer health consciousness and current smoking in both sexes and poor self-rated health in men, were significantly related to higher non-participation rates. In both sexes, individuals who did not participate in community activities were significantly more likely to be non-participants than individuals who did (aOR = 1.94, SE 0.23 in men, aOR = 3.29, SE 0.39 in women). Having low IADL and physical functioning scores were also associated with higher rates of non-participation. CONCLUSION: Health consciousness and lack of community activity participation were predictors of non-participation in a physical checkup examination among older adults. In addition, lower IADL and physical functioning/strength were also predictors of non-participation. On the contrary, older inhabitants living with someone tended to participate in the physical checkup examination for social interchange when they were frequently alone in the household. This study suggests the importance of considering aging especially for women and poor sociodemographic background and physical frailty for both sexes so that older people can access health programs without difficulty. TRIAL REGISTRATION: UMIN000008105 . Registered 26 April 2012. Retrospectively registered.

Validity of a triaxial accelerometer and simplified physical activity record in older adults aged 64-96 years: a doubly labeled water study.

BACKGROUND: The aim was to examine the validity of a triaxial accelerometer (ACCTRI) and a simplified physical activity record (sPAR) in estimating total energy expenditure (TEE) and physical activity level (PAL) in older adults with the doubly labeled water (DLW) method. METHODS: A total of 44 Japanese elderly individuals (64-96 years), of which 28 were community-dwelling healthy adults with or without sporting habits (S or NS group) and 16 were care home residents with frailty (F group), were included in the study. Basal metabolic rate (BMR) was measured by indirect calorimetry, TEE was obtained by the DLW method, and PAL was calculated as TEE/BMR. Daily step count was monitored by a pedometer (Lifecorder). The 24-h average metabolic equivalent was assessed by ACCTRI and sPAR. RESULTS: The TEEDLW in men was 2704 ± 353, 2308 ± 442, and 1795 ± 338 kcal d-1, and that in women was 2260 ± 208, 1922 ± 285, and 1421 ± 274 kcal d-1 for the S, NS, and F groups, respectively. ACCTRI and sPAR systematically underestimated actual TEE (- 14.2 ± 11.6 and - 15.3 ± 12.3% for ACCTRI and sPAR, respectively). After diet-induced thermogenesis was taken into account for ACCTRI and sPAR, TEEDLW was significantly correlated with TEEACCTRI (R2 = 0.714) and TEEsPAR (R2 = 0.668). PALDLW was also significantly correlated with PALACCTRI (R2 = 0.438) and PALsPAR (R2 = 0.402). CONCLUSIONS: Age, living conditions, frailty, and sporting habits contribute to TEE and PAL in the elderly population. ACCTRI and sPAR underestimated TEE and PAL, and adequate corrections are required. The corrected ACCTRI and sPAR are both useful tools to estimate TEE and PAL.