著者
Masaki Machida Tomoko Takamiya Shiho Amagasa Hiroshi Murayama Takeo Fujiwara Yuko Odagiri Hiroyuki Kikuchi Noritoshi Fukushima Mitsuo Kouno Yu Saito Fumitoshi Yoshimine Shigeru Inoue Yugo Shobugawa
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.32, no.11, pp.489-495, 2022-11-05 (Released:2022-11-05)
参考文献数
43
被引用文献数
7 6

Background: The hippocampus is a brain structure important for memory and cognitive function. Physical activity may help prevent hippocampal atrophy. However, few studies have measured sedentary behavior (SB) and intensity-specific physical activity using an accelerometer. This study aimed to examine the cross-sectional associations of objectively-determined SB, light-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) measured by an accelerometer with hippocampal volume among community-dwelling older adults using compositional data analysis (CoDa) approach.Methods: This cross-sectional study was part of the Neuron to Environmental Impact across Generations (NEIGE) study. A randomly recruited sample of 485 Japanese older adults (47% male; aged 65–84 years) wore tri-axial accelerometers (Omron Healthcare) for 7 consecutive days in 2017. Hippocampal volume was measured with magnetic resonance imaging and the left and right hippocampal volumes were automatically segmented using FreeSurfer software. Associations of sedentary and physically active behaviors with hippocampal volume were examined with compositional linear regression analysis based on isometric log-ratio transformations of time use adjusted for potential confounding factors.Results: The relative proportion of time spent in MVPA, compared to the other two activities, was significantly positively associated with right hippocampal volume (β: 57.1, P-value = 0.027). However, no association existed between higher proportions of MVPA and left hippocampal volume, or between proportions of SB or LPA with either left or right hippocampal volumes.Conclusion: The proportion of time spent in MVPA, relative to the other two activities, was significantly positively associated with right hippocampal volume. MVPA may be beneficial for maintaining hippocampal volume.
著者
Yuiko Nagamine Takeo Fujiwara Yukako Tani Hiroshi Murayama Takahiro Tabuchi Katsunori Kondo Ichiro Kawachi
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.30, no.11, pp.497-502, 2020-11-05 (Released:2020-11-05)
参考文献数
36
被引用文献数
8

Background: Socioeconomic mobility affects health throughout the life course. However, it is not known whether there are gender differences in the association between life-course subjective socioeconomic status (SSS) mobility and mortality at older ages.Methods: Participants were 16,690 community-dwelling adults aged 65–100 years in the Japan Gerontological Evaluation Study (JAGES). Baseline information including demographic characteristics, depression, and lifestyle factors were collected in 2010. Participants’ vital status was confirmed in 2013 via linkage to death records. We categorized life-course socioeconomic mobility into the following categories: ‘persistently high’, ‘downward mobility’, ‘upward mobility’, and ‘persistently low’. Cox proportional hazard modeling was used to estimate hazard ratios (HR) for all-cause mortality.Results: Mortality HRs for the ‘downward’ group were 1.37 (95% confidence interval [CI], 1.08–1.74) among men and 1.27 (95% CI, 0.94–1.71) among women in comparison with the ‘persistently high’ group. Compared to the ‘persistently low’ group, the HRs for the ‘upward’ group were 0.54 (95% CI, 0.35–0.83) among women and 0.91 (95% CI, 0.73–1.24) among men. Associations were not changed after adjusting for objective socioeconomic status but were attenuated by depression.Conclusions: ‘Downward’ mobility was associated with mortality among men, but not among women. Depression appeared to mediate the association. A protective effect of upward mobility was observed among women but not among men.
著者
Yugo Shobugawa Hiroshi Murayama Takeo Fujiwara Shigeru Inoue
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.30, no.7, pp.281-287, 2020-07-05 (Released:2020-07-07)
参考文献数
28
被引用文献数
14

Background: Studies have shown that rural residents face disadvantages concerning medical access and socio-economic conditions. However, the social determinants of health among older people in rural areas are still unclear. The Neuron to Environmental Impact across Generations (NEIGE) study investigated the social determinants of health among older rural adults.Methods: A survey was conducted among the older residents of Tokamachi City, Japan. We randomly selected study participants (N = 1,346) from four stratified groups by age (65–74 and 75–84 years) and residential area (Tokamachi center [downtown] and Matsunoyama [mountain]). The survey collected data on socio-economic status, lifestyle, health, and neighborhood environment. Blood and urine sampling were also conducted, and physical activity was assessed. Magnetic resonance brain imaging (MRI) and Apo-E gene were also examined in the analysis.Results: In total, 527 people participated in the NEIGE study (participation rate: 39.2%). The average age of the participants was 73.5 (standard deviation, 5.6) years, and 47.3% were male. No differences in demographics were found between downtown and mountain residents, except for educational attainment, which was lower among mountain residents. Lifestyles were similar, except for the higher percentage of everyday drinkers (33.3–35.3%) in the mountain area. Concerning physical health, muscle mass, grip strength, and measured physical activity were significantly higher among mountain residents. However, gait speed and balance were better among downtown residents.Conclusion: The findings of the NEIGE study will help elucidate the social determinants of health in older rural adults in Japan, and emphasize the different outcomes between downtown and mountain areas.
著者
Shiho Amagasa Shigeru Inoue Hiroshi Murayama Takeo Fujiwara Hiroyuki Kikuchi Noritoshi Fukushima Masaki Machida Sebastien Chastin Neville Owen Yugo Shobugawa
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20190141, (Released:2019-10-26)
参考文献数
45
被引用文献数
22

Background: Physical activity can help to protect against cognitive decline in older adults. However, little is known about the potential combined relationships of time spent in sedentary behavior (SB), light-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) with indices of cognitive health. We examined the cross-sectional associations of objectively-determined sedentary and physically-active behaviors with an indicator of cognitive function decline (CFD) in older adults.Methods: A randomly-recruited sample of 511 Japanese older adults (47% male; aged 65-84 years) wore a tri-axial accelerometer (HJA-750C, Omron) for seven consecutive days in 2017. Cognitive function was assessed by interviewers using the Japanese version of Mini-Mental State Examination, with a score of ≤23 indicating CFD. Associations of sedentary and physically-active behaviors with CFD were examined using a compositional logistic regression analysis based on isometric log-ratio transformations of time use, adjusting for potential confounders.Results: Forty one (9.4%) of the participants had an indication of CFD. Activity compositions differed significantly between CFD and normal cognitive function (NCF); the proportion of time spent in MVPA was 39.1% lower, relatively to the overall mean composition in those with CFD, and was 5.3% higher in those with NCF. There was a significant beneficial association of having a higher proportion of MVPA relative to other activities with CFD. LPA and SB were not associated with CFD when models were corrected for time spent in all activity behaviors.Conclusions: Larger relative contribution of MVPA was favorably associated with an indicator of CFD in older adults.
著者
村山 博 Hiroshi Murayama 桃山学院大学経営学部
出版者
桃山学院大学総合研究所
雑誌
桃山学院大学経済経営論集 = ST. ANDREW'S UNIVERSITY ECONOMIC AND BUSINESS REVIEW (ISSN:02869721)
巻号頁・発行日
vol.49, no.3, pp.1-37, 2007-11-20

The old innovation was eliminating the products of the other companies from the market, spreading only the products of one's company widely, and raising the market share as much as possible. It was no longer a business goal to win the competition with the other companies after the information technology innovation. Then some companies are beginning to look for a new innovation or a business goal. That is the innovation that companies do not compete with the other companies but cooperates with the competitors in the market. The innovation consists of the competitor's bunches which harmonize both competition and accordance and can make new products and new technologies which we have never seen before. This innovation from the viewpoint of customers or markets differs from the old innovations greatly. The innovation will be indispensable in the internet community. This paper studies the innovation which cooperates with the other companies and considered the hybrid car of Toyota, the digital broadcasting of Disney, the development of the Linux software, etc. The following conclusions were reached. Vertical accordance" of this innovation carries out the synchronization of the three innovations, such as development, manufacturing, and distribution. And Horizontal accordance" of this innovation has the synergy by cooperative development and licensing with the other companies. We can call it the innovation of innovations. The local brands, merchandising rights, open source methods, cooperative research and cooperative development, licensing among other companies, the de facfo standards are the brand new innovations which cooperates with the other companies. Some companies of the specific community manufacture and sell using the same local brand. The accordance between companies by this local brand can acquire the large cost performance and the synergy which the only one company cannot acquire. It can be called the accordance innovation. The source code of the Linux software was opened to the entire world. Then, the developers connected with the Internet in the world have performed the development of the Linux software. As a result, the Linux software became such wonderful software that Microsoft is threatened. This open source method is the new accordance innovation in the internet community. This paper also studies the problems of the new innovations, such as the matter on which researchers escape from the development, the matter on which the competition stagnates, and the matter on which the standards monopolize the market.
著者
Hiroshi Murayama Yu Nofuji Eri Matsuo Mariko Nishi Yu Taniguchi Yoshinori Fujiwara Shoji Shinkai
出版者
日本疫学会
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
pp.JE20140065, (Released:2014-09-06)
参考文献数
28
被引用文献数
2 6

Background: Further evidence into the effects of social relationships on health (including those at both the individual and community levels) is needed in Japan. The Yabu Cohort Study was launched in 2012 to identify the associations between social relationships and health among community-dwelling older Japanese people and to evaluate population approaches for preventive long-term care in the community. This report describes the study design and the profile of the participants at baseline.Methods: The Yabu Cohort Study is a prospective study of community-dwelling individuals aged 65 years and older in Yabu, Hyogo Prefecture, Japan. The baseline survey, using a mailed self-administered questionnaire, was conducted from July through August 2012. It included information on socioeconomic status, general and psychological health, and social relationships (social network, social support, and social capital). Survival time, long-term care insurance certification, and medical and long-term care costs after the baseline survey will be followed.Results: Of 7271 questionnaires distributed, a total of 6652 were returned (91.5% response rate), and 6241 were included in the analysis. Mean age was 71.9 ± 5.2 years, 43.2% were men, and 83.8% had lived in their neighborhood for more than 40 years. Approximately 45.2% expressed general trust. About 82.4%, 49.9%, and 55.5% have participated in neighborhood association activities, municipal seminars for preventive long-term care, and salon activities in the community, respectively.Conclusions: The study is expected to provide valuable evidence on the effects of social relationships on health and to suggest the usefulness of population approaches for preventive long-term care in Japanese communities.