岡山医学会 Acta Medica Okayama 0030-1558 133 1 2021 医療政策とその課題 ― 日本の国民皆保険制度は持続可能か？ 30 35 EN Jun Hamada Department of Health Economics and Policy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 0030-1558 131 3 2019 医師の働き方改革 165 167 EN Jun Hamada Department of Health Economics and Policy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences No potential conflict of interest relevant to this article was reported.

PeerJ Acta Medica Okayama 2167-8359 7 2019 Combined effects of body mass index and unhealthy behaviors on disability in older Japanese adults: the Okayama study e8146 EN Yangyang Liu Department of Epidemiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiharu Mitsuhashi Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama University Michiyo Yamakawa Department of Epidemiology and Preventive Medicine, Graduate School of Medicine,Gifu University Megumi Sasai Sri Lanka Office, Japan International Cooperation Agency Toshihide Tsuda Department of Human Ecology, Graduate School of Environmental and Life Science, Okayama University Hiroyuki Doi Department of Epidemiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Jun Hamada Department of Health Economics and Policy, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background: Body mass index (BMI) is a significant predictor of functional disability in older adults. However, when evaluated, the association between BMI and incident functional disability, considering behaviors only as covariates or not, may not be appropriate. The primary purpose of the study was to investigate the combined effects of BMI and unhealthy behaviors on the risk of incident functional disability. Methods: This was a retrospective cohort study that took place in Okayama City, Japan. Data on BMI and unhealthy behaviors were obtained using the health check-up questionnaire. The certification of Long-Term Care Insurance was used to measure functional disability. Cox proportional hazard models were used; adjusted hazard ratios (HRs) with 95% confidence interval (CI) were calculated for incidence of functional disability across categories of BMI and number of unhealthy behaviors. Results: The relationship between BMI and incident functional disability was U-shaped (HR = 1.18, 95% CI [1.11-1.25], among the underweight range; and 1.26 [1.19-1.34] among the obesity range), and its risk was significantly higher within the normal-to-overweight range of BMI values with co-occurring unhealthy behaviors (with normal weight range and one, 1.17 [1.01-1.21]; two, 1.29 [1.18-1.41]; and three or four unhealthy behaviors 1.38 [1.24-1.54]; as well as among overweight range and one, 1.16 [1.05-1.27]; two, 1.26 [1.15-1.38]; and three or four unhealthy behaviors, 1.47 [1.31-1.64]). In each BMI category, the risk of incident functional disability increased with increasing number of unhealthy behaviors (p < 0.05 for linear tread), with the highest risk (1.87 [1.58-2.20]) occurring in combination with at least three unhealthy behaviors with BMI >= 27.5, for both sexes (2.20 [1.64-2.92] in men and 1.66 [1.35-2.04] in women). Conclusion: It is necessary to consider the combined effects of BMI and behaviors on incident functional disability. Furthermore, interventions targeting multiple behaviors should be considered as such interventions may offer greater benefits than simple interventions. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 66 4 2012 Does Caregiver’s Social Bonding Enhance the Health of their Children?:The Association between Social Capital and Child Behaviors 343 350 EN Takeo Fujiwara Soshi Takao Toshihide Iwase Jun Hamada Ichiro Kawachi Original Article 10.18926/AMO/48689 Little is known about the association between social capital and child behaviors. This study aims to investigate that association. A complete population-based, cross-sectional survey was conducted for all the caregivers with preschool children in a rural town in Okayama prefecture in Japan. Two dimensions of individual-level social capital and unhealthy child behaviors were reported by parent-administered questionnaire. We analyzed 354 preschool children (57.6% of all children for whom questionnaires were completed). Children whose main caregiver had high cognitive social capital were 89% less likely to miss breakfast (odds ratio [OR]＝0.11;95% confidence interval [CI]:0.01-1.03). Children whose caregiver had high structural social capital were 71% less likely to wake up late (OR＝0.29;95% CI:0.12-0.71) and 78% less likely to skip tooth brushing more than once per day (OR＝0.22;95% CI:0.05-0.93). Both cognitive and structural social capital were negatively associated with unhealthy child behaviors. A further intervention study is needed to confirm the impact of social capital on child behavior. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 62 5 2008 Policy Implications of Social Capital for the Japanese Social Security System 275 283 EN Jun Hamada Soshi Takao Review 10.18926/AMO/30971 We discuss the concept of social capital, which has received much attention recently. Social capital is important for the following 2 key reasons:(1) a highly democratic polity and a strong economic performance that attaches great importance to the public good can be achieved on the basis of high social capital;and (2) social capital can effect health status in the human population, and widening of income inequality harms human health through the erosion of social capital. In addition, there are 3 political implications of social capital for Japanese society:(1) social capital has implications for the political decision of whether Japanese society should adopt a “medium burden for medium welfare” or a “low burden for small welfare” model together with the concept of social overhead capital;(2) reciprocity, which is one of the primary components of social capital, is similar to the philosophy underlying the health care system of Japan;(3) Japanese society needs to change from a society that emphasizes the relationships between its members to a society that is open to outsiders and has sufficient opportunities. No potential conflict of interest relevant to this article was reported.

岡山医学会 Acta Medica Okayama 00301558 119 2 2007 医療政策論の現況 131 136 EN Jun Hamada No potential conflict of interest relevant to this article was reported.