Why are the Japanese living longer?

Greater nurse density correlates to higher level of population ageing globally, but is more prominent in developed countries

BACKGROUND

Representing over 50% of the healthcare workforce, nurses provide care to people at all ages. This study advances, at a population level, that high levels of nursing services, measured by nurse density may significantly promote population ageing measured by the percentage of a population over 65 years of age (65yo%).

METHODS

Population level data was examined to explore the correlation between nurse density and 65yo%. The confounding impacts on ageing such as the effects of economic affluence, physician density, fertility rate, obesity and urban advantages were also considered. Scatter plots, bivariate correlation, partial correlation and multiple linear regression analyses were performed for examining the correlations.

RESULTS

Nurse density correlated to 65yo%; this relationship was independent of other influences such as fertility rate, economic affluence, obesity prevalence, physician density and urban advantages. Second to fertility rate, nursing density had the greatest influence on 65yo%. The predicting and confounding variables explain 74.4% of the total 65yo% variance. The universal correlations identified in country groupings suggest that low nurse density may be a significant global concern.

CONCLUSIONS

While nurse density might contribute significantly to 65yo% globally, the effect was more prominent in developed countries. Ironically, countries with higher nurse densities and therefore greater levels of 65yo%, were countries with an increased need for more nursing staff. To highlight the profound implications for the role the nursing profession plays especially at a time of global nursing shortage, further study into the effects of long-run elasticity of nurse staffing level on population ageing may be needed. For instance, what percentage of nursing staff increase would be required to meet every 1% increase of an ageing population.

Longitudinal Changes in Occupational Balance among Baby Boomers in Japan (1996-2016)

In Japan, the proportion of the older adult population-the post-war baby boomer generation-is increasing rapidly and presenting new problems, such as suicide among baby boomers and the burden of family care. The purpose of this study was to clarify how baby boomers changed their occupational balance between their 40s and 60s. This study used public statistical data from the Survey on Time Use and Leisure Activities published by the Statistics Bureau of Japan to analyze the longitudinal characteristics of the time allocation of baby boomers. The findings of this study showed gender differences in occupational balance among the study population. The occupational balance of men changed due to occupational transition after mandatory retirement, but that of women did not change significantly. Longitudinally examining the time allocation changes of one generation revealed that the readjustment of occupational balance is necessary during life role changes, such as retirement. Moreover, if this readjustment is not carried out properly, individuals will experience role overload and loss.

Preventive role of community-level social capital in the need for long-term care and impairment in instrumental activities of daily living: a multilevel analysis

BACKGROUND

Individual-level social capital is an important determinant of older adults' long-term care needs; however, there is scant evidence regarding community-level social capital. Therefore, we investigated the association between community-level social capital and the prevalence of the need for long-term care among older adults.

METHODS

Between January and February 2018, a cross-sectional survey was conducted among all older adults (n = 13,558) aged 65 to 74 years in a rural municipality in Japan (total population, n = 72,833). A self-reported questionnaire was used to identify community-level social capital, comprising civic participation, social cohesion, and reciprocity. A multilevel logistic regression analysis was performed to estimate the odds ratios of the need for long-term care and a decline in social activity competence as assessed by instrumental activities of daily living. For the analysis, the community levels were divided into 76 voting districts and adjusted for daily life, lifestyle, socioeconomic status, health conditions, and the three social capital subscale scores at the individual level.

RESULTS

After adjusting for the covariates, we observed a tendency that a higher community level of reciprocity was associated with a lower prevalence of long-term care needs (OR: 0.86, 95% confidence interval: 0.75-1.00), whereas a high community level of social cohesion was associated with a significantly reduced decline in instrumental activities of daily living (OR per standard deviation increase: 0.87, 95% confidence interval: 0.79-0.96). No significant association was found with civic participation. Similarly, individual-level social capital was associated with the need for long-term care and decline in instrumental activities of daily living.

CONCLUSIONS

Our findings suggest that good community-level reciprocity or social cohesion as well as good individual social capital status may help prevent the need for long-term care among older adults.

Physician care access plays a significant role in extending global and regional life expectancy

BACKGROUND

Previous cross-sectional studies generally did not fully consider the potential confounding factors associated with physician impact on overall population health. This ecological study controlled for health, demographic and socioeconomic confounders while using total physician density for predicting overall population health globally and regionally.

METHODS

Ecological data were extracted from the United Nations agencies for 215 populations. Considering the competing effects of economic affluence, urban advantages and obesity, correlations between physician density and life expectancy at birth (LEB) were analysed with scatter plots, bivariate correlation, partial correlation and multiple linear regression analyses. Countries are also grouped for exploring the regional correlations between physician density and LEB.

RESULTS

Physician density correlates to LEB and this relationship remains regardless of the competition of the individual confounders, economic affluence, urbanization and obesity, or their combination. Physician density has the greatest influence on LEB, while economic affluence is second. Physician density explains 64.89% of LEB in this study. Together with constant bivariate correlations in country groupings, power correlation without a plateau or U shape in the trendline of the scatterplots, suggests that a shortage of physicians is a worldwide issue.

CONCLUSIONS

Physician density is a major independent contributor for LEB both globally and with special regard to the developing world. Telehealth may be an alternative to increase physicians' capacity while funding for increasing physician employment is desirable.

Associations between social fragmentation, socioeconomic deprivation and suicide risk across 1887 municipalities in Japan, 2009-2017: a spatial analysis using the Bayesian hierarchical model

OBJECTIVE

Previous studies have indicated that spatial variation in suicide mortality is associated with area-specific socioeconomic characteristics, such as socioeconomic deprivation and social fragmentation. However, most of these studies have been conducted in the West and findings from Asian countries are limited. This study aims to investigate associations between socioeconomic characteristics and suicide mortality rates across 1887 municipalities in Japan between 2009 and 2017. We also assessed these associations by gender and age group.

METHODS

Suicide data were obtained from the suicide statistics of the Ministry of Health, Labour and Welfare in Japan and included information on the number of suicides by gender, age and municipality location. Social fragmentation, socioeconomic deprivation and urbanicity were used as socioeconomic characteristics in this study and were created from survey data obtained from the 2010 census. Bayesian hierarchical models were used to examine associations between socioeconomic characteristics and suicide risk.

RESULTS

Suicide rates were significantly higher in municipalities with higher levels of deprivation, with a rate ratio of 1.13 (95% credible interval: 1.10 to 1.17) in the highest quartile compared with the lowest. Higher levels of urbanicity had significantly lower suicide rates, with a rate ratio of 0.79 (95% credible interval: 0.77 to 0.82) in the highest quartile compared with the lowest. However, associations between exposures and suicide varied considerably by gender and age. Among both men and women aged 0-39 years, fragmentation was significantly associated with suicide, with rate ratios of 1.07 and 1.15 for men and women, respectively, in the highest quartile compared with the lowest.

CONCLUSION

Suicide prevention in Japan should particularly focus on areas with high levels of deprivation or low levels of urbanicity. Furthermore, young Japanese people residing in the most fragmented municipalities were also at high risk of suicide, and appropriate measures need to be taken.

Educational inequalities in adult mortality: a systematic review and meta-analysis of the Asia Pacific region

OBJECTIVES

In this study, we aim to analyse the relationship between educational attainment and all-cause mortality of adults in the high-income Asia Pacific region.

DESIGN

This study is a comprehensive systematic review and meta-analysis with no language restrictions on searches. Included articles were assessed for study quality and risk of bias using the Joanna Briggs Institute critical appraisal checklists. A random-effects meta-analysis was conducted to evaluate the overall effect of individual level educational attainment on all-cause mortality.

SETTING

The high-income Asia Pacific Region consisting of Japan, South Korea, Singapore and Brunei Darussalam.

PARTICIPANTS

Articles reporting adult all-cause mortality by individual-level education were obtained through searches conducted from 25 November 2019 to 6 December 2019 of the following databases: PubMed, Web of Science, Scopus, EMBASE, Global Health (CAB), EconLit and Sociology Source Ultimate.

PRIMARY AND SECONDARY OUTCOME MEASURES

Adult all-cause mortality was the primary outcome of interest.

RESULTS

Literature searches resulted in 15 345 sources screened for inclusion. A total of 30 articles meeting inclusion criteria with data from the region were included for this review. Individual-level data from 7 studies covering 222 241 individuals were included in the meta-analyses. Results from the meta-analyses showed an overall risk ratio of 2.40 (95% CI 1.74 to 3.31) for primary education and an estimate of 1.29 (95% CI 1.08 to 1.54) for secondary education compared with tertiary education.

CONCLUSION

The results indicate that lower educational attainment is associated with an increase in the risk of all-cause mortality for adults in the high-income Asia Pacific region. This study offers empirical support for the development of policies to reduce health disparities across the educational gradient and universal access to all levels of education.

PROSPERO REGISTRATION NUMBER

CRD42020183923.

Inequality within a community at the neighborhood level and the incidence of mood disorders in Japan: a multilevel analysis

PURPOSE

This study analyzes whether income inequality within a community at the neighborhood level is associated with incidence of mood disorder in Japan.

METHODS

A retrospective cohort study was performed using the data of 116,658 National Health Insurance beneficiaries aged between 20 and 69 in Chiba City, Japan. To evaluate income inequality within a community, the Gini coefficient within a 30-min walking distance from an individual's residence was calculated using income distribution estimated by the National Census and the Housing and Land Survey 2013. Incidence of mood disorder was determined through insurance claims submitted from April 1, 2013, to March 31, 2016. A multilevel logistic analysis with three levels-the individual, household, and residential district-was performed to evaluate the association.

RESULTS

Income inequality within a community at the neighborhood level was not associated with incidence of mood disorder in the models with and without equivalent household income (p for trend = 0.856 and 0.947, respectively). No difference was observed in the impact of the Gini coefficient among income levels, lower versus higher income groups (p for interaction between Gini coefficient and household income = 0.967). In contrast, lower equivalent income at the household level was significantly associated with higher incidence of mood disorder (p for trend < 0.001).

CONCLUSIONS

While we confirmed that lower income at the household level itself had an adverse effect on mental health, income inequality within a community at the neighborhood level was not a significant factor for incidence of mood disorder in Japan.

Comparison of Prognostic Accuracy of the quick Sepsis-Related Organ Failure Assessment between Short- & Long-term Mortality in Patients Presenting Outside of the Intensive Care Unit - A Systematic Review & Meta-analysis

The purpose of this meta-analysis was to compare the ability of the qSOFA in predicting short- (≤30 days or in-hospital mortality) and long-term (>30 days) mortality among patients outside the intensive care unit setting. Studies reporting on the qSOFA and mortality were searched using MEDLINE and SCOPUS. Studies were included if they involved patients presenting to the ED with suspected infection and usage of qSOFA score for mortality prognostication. Data on qSOFA scores and mortality rates were extracted from 36 studies. The overall pooled sensitivity and specificity for the qSOFA were 48% and 86% for short-term mortality and 32% and 92% for long-term mortality, respectively. Studies reporting on short-term mortality were heterogeneous (Odd ratio, OR = 5.6; 95% CI = 4.6-6.8; Higgins's I2 = 94%), while long-term mortality studies were homogenous (OR = 4.7; 95% CI = 3.5-6.1; Higgins's I2 = 0%). There was no publication bias for short-term mortality analysis. The qSOFA score showed poor sensitivity but moderate specificity for both short and long-term mortality, with similar performance in predicting both short- and long- term mortality. Geographical region was shown to have nominal significant (p = 0.05) influence on qSOFA short-term mortality prediction.

Social and Behavioural Determinants of the Difference in Survival among Older Adults in Japan and England

BACKGROUND

A rapidly ageing population presents major challenges to health and social care services. Cross-country comparative studies on survival among older adults are limited. In addition, Japan, the country with the longest life expectancy, is rarely included in these cross-country comparisons.

OBJECTIVE

We examined the relative contributions of social and behavioural factors on the differences in survival among older people in Japan and England.

METHODS

We used data from the Japan Gerontological Evaluation Study (JAGES; n = 13,176) and the English Longitudinal Study of Ageing (ELSA; n = 5,551) to analyse all-cause mortality up to 9.4 years from the baseline. Applying Laplace regression models, the 15th survival percentile difference was estimated.

RESULTS

During the follow-up, 31.3% of women and 38.6% of men in the ELSA died, whereas 19.3% of women and 31.3% of men in the JAGES died. After adjusting for age and baseline health status, JAGES participants had longer survival than ELSA participants by 318.8 days for women and by 131.6 days for men. Family-based social relationships contributed to 105.4 days longer survival in JAGES than ELSA men. Fewer friendship-based social relationships shortened the JAGES men's survival by 45.4 days compared to ELSA men. Currently not being a smoker contributed to longer survival for JAGES women (197.7 days) and ELSA men (46.6 days), and having lower BMI reduced the survival of JAGES participants by 129.0 days for women and by 212.2 days for men.

CONCLUSION

Compared to participants in England, Japanese older people lived longer mainly because of non-smoking for women and family-based social relationships for men. In contrast, a lower rate of underweight, men's better friendship-based social relationships, and a lower smoking rate contributed to survival among participants in England.

Parental Socioeconomic Status and Weight Faltering in Infants in Japan

Background: Previous studies in the UK and Denmark found no significant association between low socioeconomic status (SES) and weight faltering. However, to our knowledge, there are no studies from other developed countries. We examined the association between parental SES and weight faltering in infants up to 1.5 years of age, and investigated whether the inequalities changed between 2001 and 2010 in Japan. Methods: We used data from two Japanese population-based birth cohorts started in 2001 (n = 34,594) and 2010 (n = 21,189). Parental SES was assessed as household income and parental education when the infant was 6 months old. Weight faltering was defined as the slowest weight gaining in 5% of all children in each cohort. Logistic regression analyses were conducted with adjustment for covariates. The relative index of inequality was used to assess relative impact of parental SES on weight faltering. Results: Infants in the lowest quartile of household income were 1.29 (95% confidence interval [CI]: 1.10, 1.52) and 1.27 (95% CI: 1.03, 1.56) times more likely to experience weight faltering than those in the highest income quartile both in the 2001 and 2010 cohorts, respectively. The relative index of inequality for household income was 1.66 (95% CI: 1.36, 1.96) in 2001 and 1.86 (95% CI: 1.42, 2.31) in 2010. Conclusions: Infants from lower income families have a greater risk of weight faltering in Japan. Additionally, the income-related inequalities in weight faltering did not change between the two cohorts. Social policies to address maldistribution of weight faltering due to household income are needed.

Household income is associated with food and nutrient intake in Japanese schoolchildren, especially on days without school lunch

Objective

The present study aimed to examine the association between household income and the intake of foods and nutrients by Japanese schoolchildren, and any differences between days with and without school lunch.

Design

This was a cross-sectional study. Children, with the support of their parents, kept dietary records with photographs for 4 d (2 d with school lunch and 2 d without). The socio-economic status of each family was obtained from a questionnaire completed by the parents.

Setting

Japan.

Subjects

All students in 5th grade (10–11 years old) at nineteen schools in four prefectures and their parents (1447 pairs of students and parents) were invited to take part in the study; 836 pairs of complete data sets were analysed.

Results

The average results of four days of dietary records showed that lower income level was associated with a lower intake of fish/shellfish, green vegetables and sugar at the food group level, a lower intake of protein and several micronutrients, and a higher energy intake from carbohydrates at the nutrient level among the children. These associations between income and food/nutrient intake were not significant on days with school lunches, but were significant on days without school lunch.

Conclusions

Our study confirmed an association between household income and the amount of foods and nutrients consumed by Japanese schoolchildren, and suggested that school lunches play a role in reducing disparities in the diets of children from households with various incomes.

Socioeconomic disparities in psychological distress in a nationally representative sample of Japanese adolescents: A time trend study

OBJECTIVE

Socioeconomic status as a determinant of mental health problems has received scant attention in Japan, which has long been considered an egalitarian society. This study examined the association between socioeconomic status and psychological distress and its trends over 6 years among Japanese adolescents.

METHODS

We used data from a nationally representative sample of 9491 adolescents aged 12-18 years who participated in three repeated cross-sectional surveys between 2007 and 2013. The K6 scale was used to assess psychological distress. Socioeconomic status indicators included household income, parental education, parental working status and household structure.

RESULTS

Psychological distress prevalence decreased significantly from 2007 (10.7%) to 2013 (7.6%). However, the socioeconomic status patterns of psychological distress were consistent through the study period. Adolescents living in both lower (odds ratio = 1.61; 95% confidence interval = [1.27, 2.05]) and higher income households (odds ratio = 1.30; 95% confidence interval = [1.03, 1.62]) were more likely to report psychological distress than their middle-income counterparts. Adolescents with low household income were more likely to feel stress from interpersonal relationships and less likely to have help-seeking behaviors, while those with high household income were more likely to feel stress about school achievement. Psychological distress was also associated with parental poor education and single parenthood.

CONCLUSIONS

Socioeconomic status disparities in adolescent psychological distress were evident and consistent during the 6-year period. There is a unique U-shaped relationship between household income and psychological distress among adolescents in Japan, unlike those from other countries. However, the underlying mechanisms may differ by income status. Future prevention efforts should consider socioeconomic status as a determinant of adolescent mental health problems.

Dietary predictors and plasma concentrations of perfluorinated alkyl acids in a Singapore population

Perfluorinated alkyl acids (PFAAs), a family of man-made organofluorinated compounds, have drawn much attention due to their ubiquitous existence in the environment and their bioaccumulation potential. Here, we examined the plasma concentrations of thirteen PFAAs in a healthy population (N = 270) in Singapore, and investigated the association between major food groups and plasma PFAA concentrations. We detected eight types of PFAAs in more than 75% of all samples (N = 270), and their median concentrations ranged from 0.05 to 8.34 ng mL^-1. Age- and gender-related differences were observed for the three dominant PFAAs, i.e., perfluorooctanesulfonic acid (PFOS), perfluorohexane sulfonate (PFHxS) and perfluorooctanoate acid (PFOA), with concentrations being higher in men and older adults. Multiple linear regression analyses showed that fish, shellfish, red meat and poultry were associated with increased PFAAs concentrations in plasma, whereas grains and soy products showed inverse associations with PFAAs. Further, significant correlations were observed between various long-chain PFAAs and plasma concentrations of omega-3 fatty acids, suggesting seafood was a significant source of these PFAAs, within this population. Future studies on diet exposure to PFAAs are encouraged to focus more on the effects on diet pattern.

Trends in socioeconomic inequalities in self-rated health, smoking, and physical activity of Japanese adults from 2000 to 2010

Health disparities in Japan are attracting increasing attention. Temporal trends in health disparities should be continuously monitored using multiple indices of socioeconomic status (SES) and health-related outcomes. We explored changes in socioeconomic differences in the health of Japanese adults during 2000–2010. The data was taken from the Japanese General Social Surveys, the cross-sectional surveys for nationally representative samples of Japanese adults. We used 14,193 samples (individuals of 20–64 years of age) in our analysis. We estimated age-adjusted prevalence ratios of the lowest SES group in comparison with the highest SES group using Poisson regression models with robust error variance. Relative index of inequality (RII) and slope index of inequality (SII) were also calculated. We examined the changes in the association between health-related outcomes (self-rated health (SRH), smoking, and physical activity) and SES indices (income, education, occupation, and subjective social class identification). The results showed temporally expanding trends for the associations of current smoking with SES, especially among women, in both relative and absolute measures. In contrast, no expanding trends were seen for SRH and physical activity. Although the smoking rates declined through the first decade of the 21st century, the socioeconomic disparities in smoking prevalence among Japanese adults expanded, especially among women. Researchers and policymakers should continuously monitor the trends that may cause future disparities in smoking-related morbidity and mortality.

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Associations of health indicators with socioeconomic status were observed in Japan.

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We identified increasing trends in smoking disparity from 2000 to 2010 in women.

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Increasing smoking disparities were seen in both relative and absolute measures.

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Expanding trends were not seen for self-rated health and physical activity.

Childhood socioeconomic disadvantage is associated with lower mortality in older Japanese men: the JAGES cohort study

BACKGROUND

Childhood socioeconomic disadvantage has been previously linked to increased mortality risk in adulthood. However, most previous studies have focused on middle-aged adults in Western contexts. Here, we sought to examine the association between childhood socioeconomic status (SES) and mortality among healthy older Japanese adults.

METHODS

We conducted a 3-year follow-up of participants in the Japan Gerontological Evaluation Study (JAGES), a population-based cohort of 65- to 103-year-old Japanese adults. Childhood SES was assessed by survey at baseline. Mortality from 2010 to 2013 was analysed for 15 449 respondents (7143 men and 8306 women). Cox regression models were used to estimate hazard ratios (HR) for risk of death.

RESULTS

A total of 754 deaths occurred during the 3-year follow-up. Lower childhood SES was significantly associated with lower mortality in men, but not in women. Compared with men growing up in more advantaged childhood socioeconomic circumstances, the age-adjusted HR for men from low childhood SES backgrounds was 0.75 [95% confidence interval (CI): 0.56-1.00]. The association remained significant after adjustment for height, education, adult SES, municipalities of residence, health behaviours, disease status and current social relationships (HR = 0.64; 95% CI 0.47-0.87). This association was stronger among men aged 75 years or older, HR = 0.67 (95% CI: 0.47-0.95), compared with men aged 65-74 years, HR = 0.90 (95% CI: 0.54-1.51).

CONCLUSIONS

Childhood socioeconomic disadvantage is associated with lower mortality among men aged 75 years or older, which may be due to selective survival, or alternatively to childhood physical training or postwar calorie restriction in this generation of Japanese males.

Some Observations on Health and Socio economic Status

Health and socio-economic status are powerfully linked. This association cannot be attributed to social-selection effects, and the unequal distribution of behavioural risk factors, such as smoking, explains only a part of the variance. Differential exposure to physical hazards plays a role, but the persistence of health differentials into the better-off social strata and the significance of relative as well as absolute living standards suggest psychosocial factors also. We outline a conceptual model that regards the clustering of adverse physical and psychosocial factors over the life course as critical. Identifying the salient physical and psychosocial factors is a formidable research mission. In pursuing this mission we should not lose sight of the key fact that socio economic health differentials are intimately bound up with material differentials, and that remediation demands strategies that counter socio-economic disparity.

Changes in life expectancy 1950-2010: contributions from age- and disease-specific mortality in selected countries

Background

Changes of life expectancy over time serve as an interesting public health indicator for medical, social and economic developments within populations. The aim of this study was to quantify changes of life expectancy between 1950 and 2010 and relate these to main causes of death.

Methods

Pollard’s actuarial method of decomposing life expectancy was applied to compare the contributions of different age- and disease-groups on life expectancy in 5-year intervals.

Results

From the 1960 to 70s on, declines in cardiovascular disease (CVD) mortality play an increasing role in improving life expectancy in many developed countries. During the past decades gains in life expectancy in these countries were mainly observed in age groups ≥65 years. A further consistent pattern was that life expectancy increases were stronger in men than in women, although life expectancy is still higher in women. In Japan, an accelerated epidemiologic transition in causes of death was found, with the highest increases between 1950 and 1955. Short-term declines and subsequent gains in life expectancy were observed in Eastern Europe and the former states of the Union of Soviet Socialist Republics (USSR), reflecting the changes of the political system.

Conclusions

Changes of life years estimated with the decomposing method can be directly interpreted and may therefore be useful in public health communication. The development within specific countries is highly sensitive to changes in the political, social and public health environment.

Electronic supplementary material

The online version of this article (doi:10.1186/s12963-016-0089-x) contains supplementary material, which is available to authorized users.

Association of household income and education with eating behaviors in Japanese adults: a cross-sectional study

BACKGROUND

Socioeconomic inequalities as social determinants of health are important issues in public health and health promotion. However, the association between socioeconomic status and eating behaviors has been investigated poorly in Japanese adults. To fill this gap, the present study examines the association of eating behaviors with household income and education.

METHODS

The sample comprised 3,137 Japanese adults (1,580 men and 1,557 women) aged 30 to 59 years who responded to an Internet-based cross-sectional survey in 2014. Data on the following eating behaviors were collected via self-report: "taking care of one's diet for health," "eating vegetables," "frequency of eating breakfast," "frequency of family breakfasts," "frequency of family dinners," "using the information on nutrition labels," and "conversations with family or friends during meals." Self-reported data on socioeconomic status (household income and education) and demographic variables (gender, age, district of residence, marital status, residence status, and employment status) were also collected. The associations between eating behaviors and household income or education were tested using binomial logistic regression analysis with eating behaviors as dependent variables and household income and education as independent variables. A trend P -value was calculated for three categories of household income (less than 3,000,000 JPY, 3,000,000-7,000,000 JPY, and over 7,000,000 JPY) and education (junior high/high school, 2-year college, and 4-year college/graduate school).

RESULTS

Higher household income and education were significantly associated with higher rates of eating vegetables, using the information on nutrition labels, and conversation with family or friends during meals in Japanese men and women. Higher household incomes were significantly associated with lower rates of frequency of family breakfasts in Japanese men and lower rates of frequency of family dinners in Japanese men and women.

CONCLUSIONS

Higher socioeconomic status as indicated by household income or education was associated with eating more vegetables and conversation with family or friends during meals in Japanese men and women. Socioeconomic status should be considered in health promotion and diet improvement.

Effects of Cardiovascular Events on End-Stage Renal Disease and Mortality in Patients With Chronic Kidney Disease Before Dialysis

Cardiovascular events (CVEs) are major complications in patients with chronic kidney disease (CKD). However, few studies have investigated the effects of CVEs on end-stage renal disease (ESRD) and mortality of pre-dialysis patients. We followed 377 CKD patients who were at stage ≥G3 at first clinic visit in the Shuuwa General Hospital between April 2005 and July 2014. After taking baseline patient data, we evaluated renal survival rates and all-cause and CVE-related mortality in patients with CVEs [(+)CVEs] and without CVEs [(-)CVEs]. A total of 99 CVEs occurred in 93 study patients (57.0% cardiac events, 43.0% cerebrovascular events, and 6.5% peripheral artery disease events). During the study period, 127 patients reached ESRD over a median of 4.51 years' follow-up. Kaplan-Meier analysis found longer renal survival rates in the (-)CVEs group compared with the (+)CVEs group. Forty patients died during the study period over a median of 5.43 years' follow-up. Survival rates for all-cause and CVE-related mortality of (-)CVEs patients were higher than in (+)CVEs patients. After adjustment for sex, age, current smoking, blood pressure, diabetes, estimated glomerular filtration rate, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, left ventricular hypertrophy, body mass index, albumin, hemoglobin, calcium, phosphate, C-reactive protein, and spot urine protein, the occurrence of CVEs was still a significant risk factor for ESRD (HR 1.516, P = 0.017) and all-cause mortality (HR 7.871, P < 0.001). Our findings suggest that the occurrence of CVEs is a potent risk factor for ESRD and mortality in CKD patients before dialysis.

Quantifying the contribution of changes in healthcare expenditures and smoking to the reversal of the trend in life expectancy in the Netherlands

Background

Since 2001 the Netherlands has shown a sharp upturn in life expectancy (LE) after a longer period of slower improvement. This study assessed whether changes in healthcare expenditure (HCE) explain this reversal in trends in LE. As an alternative explanation, the impact of changes in smoking behavior was also evaluated.

Methods

To quantify the contribution of changes in HCE to changes in LE, we estimated a health-production function using a dynamic panel regression approach with data on 19 OECD countries (1980–2009), accounting for temporal and spatial correlation. Smoking-attributable mortality was estimated using the indirect Peto-Lopez method.

Results

As compared to 1990–1999, during 2000–2009 LE in the Netherlands increased by 1.8 years in females and by 1.5 years in males. Whereas changes in the impact of smoking between the two periods made almost no contribution to the acceleration of the increase in LE, changes in the trend of HCE added 0.9 years to the LE increase between 2000 and 2009. The exceptional reversal in the trend of LE and HCE was not found among the other OECD countries.

Conclusion

This study suggests that changes in Dutch HCE, and not in smoking, made an important contribution to the reversal of the trend in LE; these findings support the view that investments in healthcare are increasingly important for further progress in life expectancy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2357-2) contains supplementary material, which is available to authorized users.

The psychometric properties of the WHOQOL-BREF in Japanese couples

This study investigated the psychometric properties of the Japanese version of the WHOQOL-BREF among 10,693 community-based married Japanese men and women (4376 couples) who were either expecting or raising a child. Analyses of item-response distributions, internal consistency, criterion validity, and discriminant validity indicated that the scale had acceptable reliability and performed well in preliminary tests of validity. Furthermore, dyadic confirmatory factor analysis revealed that the theoretical factor structure was valid and similar across partners, suggesting that men and women define and value quality of life in a similar way.

Work Content and Serious Mental Illness among Middle-Aged Men: Results from a 6-Year Longitudinal Study in Japan

Objective

The present study aimed to determine prospective associations between work content after a working life of more than 20 years and serious mental illness among Japanese men aged 50 to 59 years, using a nationwide population-based survey.

Methods

Data were extracted from a national longitudinal survey of middle-aged and elderly persons previously conducted by the Ministry of Health, Labour and Welfare in Japan. We analyzed data across 10 work content categories for Japanese men who had been working in the same job type or industry for over 20 years. As part pf the survey, participants completed the Kessler (K)6 scale each year to determine their level of psychological distress (with scores ≥13 indicating serious mental illness). Cox discrete time proposal hazard regression analysis was used to examine potential associations between work content and serious mental illness from 2005 to 2010. Further adjustments were made for other sociodemographic characteristics and lifestyle factors.

Results

The current study involved a total of 11,942 participants with a mean (± standard deviation [SD]) of follow-up was 3.4 (± 2.0) years, during which time 892 participants (7.5%) had been classified as having a new-onset serious mental illness. Men who had worked in service jobs and in manufacturing jobs at baseline were more likely to develop serious mental illness than those in managerial jobs (hazard ratio 1.37, 1.30, 95% confidence intervals 1.04–1.80, 1.02–1.65) after adjustment for confounding variables.

Conclusion

These findings suggest that Japanese men aged 50 to 59 years who have worked in service and manufacturing jobs after a working life of over 20 years have an increased risk of serious mental illness during follow-up. Identifying the most at-risk work content category after a working life of over 20 years would be an essential part of providing more effective interventions for psychological distress among Japanese men in this age group.

Socioeconomic status and self-reported health among middle-aged Japanese men: results from a nationwide longitudinal study

OBJECTIVE

To examine potential associations between socioeconomic factors and self-rated health among a national sample of Japanese men aged 50-59 years between 2005 and 2010, including the 2008 global financial crisis.

DESIGN

Prospective cohort study.

SETTING

Randomly selected 2515 census areas from a total of 1.8 million census areas in Japan.

PARTICIPANTS

This study utilised data from a national, longitudinal survey conducted by the Ministry of Health, Labour and Welfare. Starting in 2005, 16,738 Japanese men aged 50-59 years were recruited and sent a questionnaire each year. We analysed data for the 6-year period (2005-2010) from participants who had worked for over 20 years in the same industry (n=9727).

MAIN OUTCOME MEASURES

We focused on worsening self-rated health status by occupation, education and employment contract.

RESULTS

Working in the manufacturing industry was associated with worsening self-rated health scores when compared to those working in management (HR=1.19; 95% CI 1.04 to 1.37). A relationship between education level and worsening self-rated health was also identified as follows: junior high school (HR=1.49; 95% CI 1.31 to 1.69), high school (HR=1.29; 95% CI 1.17 to 1.42), and vocational college (HR=1.25; 95% CI 1.07 to 1.46), when compared with those holding university-level qualifications. Precarious employment (HR=1.17; 95% CI 1.00 to 1.37) was also associated with worsening self-rated health status in the current study.

CONCLUSIONS

This study suggests that working in manufacturing for more than 20 years and having lower education levels may have a significant impact on the self-rated health of middle-aged Japanese men. This may reflect a progressive decline in Japanese working conditions following the global financial crisis and/or the impact of lower socioeconomic status.

Socioeconomic Status and Overweight: A Population-Based Cross-Sectional Study of Japanese Children and Adolescents

BACKGROUND

Socioeconomic status (SES) as a determinant of obesity has received scant attention in Japan. This study examined the association between SES and overweight among Japanese children and adolescents.

METHODS

Cross-sectional analyses of a representative sample of Japanese children (6-11 years: n = 397) and adolescents (12-18 years: n = 397) were performed, with measured heights and weights from the 2010 National Health and Nutrition Examination Survey and the 2010 Comprehensive Survey of Living Conditions. Overweight, including obesity, was defined by International Obesity Task Force cut-offs. SES indicators included household income, equivalent household expenditure, parental educational attainment, and parental occupational class.

RESULTS

Overweight prevalence was 12.3% in children and 9.1% in adolescents. Adolescents living in middle-income households were more likely to be overweight than those living in high-income households (OR 2.26, 95% CI, 1.01-5.67) after adjustment for age, sex, and parental weight status. Similarly, adolescents living in households with low expenditure levels were more likely to be overweight than those living in households with high expenditure levels (OR 3.40, 95% CI, 1.20-9.60). In contrast, no significant association was observed among children.

CONCLUSIONS

Our results indicated that low household economic status was associated with being overweight, independent of parental weight status, among Japanese adolescents.

Improvement of serum zinc levels in young Japanese women by provision of food information

We investigated whether or not an intervention of providing food information improves serum Zn levels in ninety-two 18-20-year-old Japanese women. The mean serum Zn level of the participants was 73.09 ± 10.56 (mean ± SD) μg/dL, where 79 % of the participants had lower than the reference Zn level (80 μg/dL) proposed by the Japan Society for Biomedical Research on Trace Elements. Participants were divided into food information (INF) group, supplement (SPL) group, and control (C) group, and their serum Zn levels were measured before and after 2 weeks of intervention. The results showed that changes in serum Zn levels were (expressed in μg/dL): 71.23 ± 8.42 to 76.83 ± 12.22 in INF group (NS; not significant), 72.72 ± 10.77 to 84.07 ± 12.03 in SPL group (P < 0.01), and 72.69 ± 9.46 to 74.52 ± 11.44 in C group (NS). Percentage of normal subjects in serum Zn level (>79 mg/dL) were significantly increased in INF group (16.7 to 40%, P < 0.05) and SPL group (17.2 to 69%, P < 0.001) by each intervention. Food information only entailed a table of food items with high Zn content (card-type) and Zn intake menu (recipes). The results suggested that providing food information is effective in improving latent low Zn in young Japanese women.

Acute Case-Fatality Rates of Stroke and Acute Myocardial Infarction in a Japanese Population: Takashima Stroke and AMI Registry, 1989–2005

Background

Few comprehensive stroke and acute myocardial infarction registries of long duration exist in Japan to illustrate trends in acute case-fatality of stroke and acute myocardial infarction with greater precision. We examined 17-year case-fatality rates of stroke and acute myocardial infarction using an entire community-monitoring registration system to investigate trends in these rates over time in a Japanese population.

Methods

Data were obtained from the Takashima Stroke and AMI Registry covering a stable population of approximately 55 000 residents of Takashima County in central Japan. We divided the total observation period of 17 years into four periods, 1989–1992, 1993–1996, 1997–2000, and 2001–2005. We calculated gender, age-specific and age-adjusted acute case-fatality rates (%) of stroke and acute myocardial infarction across these four periods.

Results

During the study period of 1989–2005, there were 341 fatal cases within 28 days of onset among 2239 first-ever stroke events and 163 fatal cases among 433 first-ever acute myocardial infarction events. The age-adjusted acute case-fatality rate of stroke was 14·9% in men and 15·7% in women. The age-adjusted acute case-fatality rate of acute myocardial infarction was 34·3% in men and 43·3% in women. The age-adjusted acute case-fatality rates of stroke and acute myocardial infarction showed insignificant differences across the four time periods. The average annual change in the acute case-fatality rate of stroke (–0·2%; 95% CI: −2·4–2·1) and acute myocardial infarction (2·7%; 95% CI: −0·7–6·1) did not change significantly across the study years.

Conclusions

The acute case-fatality rates of stroke and acute myocardial infarction have remained stable from 1989 to 2005 in a rural and semi-urban Japanese population.

Personal factors associated with smoking among marginalized and disadvantaged youth in Japan. A strong relationship between smoking and convenience store use

Background

A national survey in Japan reported that the prevalence of smoking among high school students has sharply decreased in recent years. However, the survey only considered students who attended regular high schools (RHSs), and Japan offers part-time high schools (PHSs) that are often attended by academically and socioeconomically disadvantaged youth.

Purpose

Therefore, we examined the smoking prevalence and smoking-related factors among PHS students.

Method

A self-administered questionnaire-based survey was conducted at six PHSs. The subjects included 540 enrolled students aged 15 to 18 years. The questionnaire included items on smoking status, smokers in the family, frequency of convenience store use, lifestyle behaviors, and health awareness. Logistic regression analysis was used to identify factors that were significantly associated with smoking.

Results

A total of 45.6 % of students had smoking experience, and 29.3 % were smokers. For males and females, the smoking prevalence was about 3 and 7–12 times higher, respectively, than that reported in the national survey. The factors found to be significantly associated with smoking included having a smoker in the family, experience with drinking alcohol, and using convenience store daily (odds ratio [OR] = 12.5) or sometimes (OR = 3.63). There was a significant dose–response relationship between smoking and convenience store use.

Conclusion

The smoking prevalence among PHS students was remarkably higher than that among RHS students. These findings suggest that marginalized and disadvantaged youth should be targeted for tobacco control, and intervention is needed to protect youth from tobacco sales and advertising at convenience stores.

Modulation of platelet aggregation-related eicosanoid production by dietary F-fucoidan from brown alga Laminaria japonica in human subjects

Laminaria japonica is traditionally eaten in Japan as a beneficial food for thrombosis. The alga contains two specific ingredients, a xanthophyll fucoxanthin (FX) and a polysaccharide, F-fucoidan (FD). The aim of the present study was to investigate whether FX or FD exhibited anti-thrombotic effects. For this purpose, three types of capsules, containing 1 mg FX, 400 mg fucoidan, and both, were prepared from the alga and administered to volunteers for 5 weeks. The dose of FD or FD+FX significantly shortened lysis time (LT) of the thrombus measured by a global thrombosis test in the blood, but FX did not. Examining the mechanism, dietary FD increased H2O2 and the secretion of prostacyclin (PGI2), a potent inhibitor of platelet aggregation, in the blood, although FD was under the detection limit in the blood, determining with its monoclonal antibody. Furthermore, in mouse experiments, dietary FD was totally excreted into the faeces and was not incorporated into the blood. We then employed a co-culture system of a Caco-2 cell monolayer with fresh human blood. The addition of FD to Caco-2 cells stimulated the expression of NADPH oxidase 1 (NOX1) and dual oxidase 2 (DUOX2) mRNA and secreted H2O2 onto the blood side accompanied by a significant increase in serum PGI2 production. These effects were invalidated by the combined addition of FD with its monoclonal antibody. The results suggested that dietary FD stimulated the expression of H2O2-producing enzymes in intestinal epithelial cells and released H2O2 into the blood, which played a signalling role to increase PGI2 production and then shortened LT for thrombi.

Japanese dietary pattern consistently relates to low depressive symptoms and it is modified by job strain and worksite supports

BACKGROUND

This study examined the association between traditional Japanese dietary pattern and depressive symptoms in Japanese workers, employing large-scale samples, considering socioeconomic status (SES) and job stress factors.

METHODS

A cross-sectional study of 2266 Japanese employees aged 21-65 years from all areas of Japan was conducted as part of the Japanese Study of Health, Occupation and Psychosocial factors related Equity (J-HOPE). Habitual diet was assessed by FFQ (BDHQ). The depression degree and job stress factors (job demand, job control, and worksite support) were measured by K6 and Job Content Questionnaire.

RESULTS

Participants with high scores for the balanced Japanese dietary pattern were significantly less likely to show probable mood/anxiety disorders (K6≥9) with multivariate adjustment including SES and job stress factors (odds ratio=0.66 [0.51-0.86], trend P=0.002). Other dietary patterns were not associated with depressive symptoms. Even after stratification by job stress factors, the Japanese dietary pattern was consistently protective against depressive symptoms. Furthermore, a highly significant difference between the first and third tertiles of the dietary pattern was observed in participants with active strain (high demand and high control) with low worksite supports (8.5 vs. 5.2, P=0.011).

LIMITATIONS

Female participant sample was relatively small.

CONCLUSIONS

Japanese dietary pattern consistently related to low depressive symptoms in this large-scale cohort of Japanese workers, even after adjusting for SES and job stress factors. The protective impact is especially strong for workers with active strain and low support. Making better use of traditional dietary patterns may facilitate reducing social disparities in mental health.

Determinants of changes in income-related health inequalities among working-age adults in Japan, 1986-2007: time-trend study

This study aimed to quantify the contributions of the factors that have influenced changes in income-related health inequalities. We used data from a nationally representative sample of Japanese men and women aged 20-59 years who participated in eight repeated cross-sectional surveys between 1986 and 2007. A concentration index (CI) was used to measure income-related inequalities in self-rated health (SRH) and decomposed into contributing factors. We then examined temporal changes in CIs and their contributing factors. Results showed that income-related inequalities in SRH, unfavourable to low-income groups, persisted throughout the study period. Despite widening income inequalities, inequalities in SRH narrowed during the period of economic stagnation since the late 1990s because of the profound deterioration in SRH among middle- to high-income groups. Decomposition analysis showed that income itself and unemployment or economic inactivity were the most important contributors to inequalities in SRH for both sexes at almost all time points. However, from 1986 to 2007, the relative contribution of income to these inequalities decreased from 78% to 14% in men and from 85% to 38% in women. By contrast, the relative contribution of unemployment or economic inactivity increased from 18% to 77% in men and from 10% to 31% in women. Our results suggest that a reduction in avoidable health inequalities could be achieved by reducing the influence of unemployment or economic inactivity on health.

Occupational class inequalities in behavioral and biological risk factors for cardiovascular disease among workers in medium- and small-scale enterprises

The aim of this cross-sectional study was to examine whether occupational class inequalities existed in the behavioral and biological risk factors for cardiovascular disease among workers in medium- and small-scale enterprises. We asked 1,900 enterprises in the Ishikawa prefecture who were users of an external heath check-up facility to supply anonymous individual data in 2009. The 446 enterprises consented to the invitation. The study population was 12,625 individuals (8,104 males and 4,521 females) 16-59 yr of age. We compared indices among occupational classes. The indices of lipid and glucose metabolism were used only for subjects 40-59 yr of age. The results of this study revealed occupational class inequalities in the prevalence of current smoking, heavy drinking and hypertension in men. These inequalities were more prominent among men in the younger age group than in the older age group. In men, the most disadvantaged occupational class was transportation workers, followed by laborers. Occupational class inequalities in smoking were also found among female workers. However, the influences of occupational class on obesity and indices of lipid or glucose metabolism were inconsistent. A strategy for health promotion that targets the disadvantaged population is necessary for the prevention of cardiovascular disease.

Social Determinants of Active Aging: Differences in Mortality and the Loss of Healthy Life between Different Income Levels among Older Japanese in the AGES Cohort Study

We examined the relationship between income, mortality, and loss of years of healthy life in a sample of older persons in Japan. We analyzed 22,829 persons aged 65 or older who were functionally independent at baseline as a part of the Aichi Gerontological Evaluation Study (AGES). Two outcome measures were adopted, mortality and loss of healthy life. Independent variables were income level and age. The occurrence of mortality and need for care during these 1,461 days were tracked. Cox regressions were used to calculate the hazard ratio for mortality and loss of healthy life by income level. We found that people with lower incomes were more likely than those with higher incomes to report worse health. For the overall sample, using the governmental administrative data, the hazard ratios of mortality and loss of healthy life-years comparing the lowest to the highest income level were 3.50 for men and 2.48 for women for mortality and 3.71 for men and 2.27 for women for loss of healthy life. When only those who responded to questions about income on the mail survey were included in the analysis, the relationships became weaker and lost statistical significance.

Health equity, aboriginal peoples and occupational therapy

BACKGROUND

In Canada, Aboriginal peoples are affected by colonial relations of power that result in poor health outcomes. Despite occupational therapists' efforts to work in a safe and competent manner with people experiencing challenges to participating in daily life, Western healthcare models reflect values that often undermine Aboriginal peoples' health and well-being.

PURPOSE

Meaningful, effective, and culturally appropriate healthcare practices cannot be fully implemented by occupational therapists without an ongoing and critical examination of occupational therapy's foundational belief systems. Only a critical examination of these foundational belief systems will enable occupational therapists to take action towards addressing these inequities, which is an important step in moving towards culturally safe care.

KEY ISSUES

Canadian health professions, including occupational therapy, have the potential to create positive change at a systems level through the critical exploration of underlying professional assumptions.

IMPLICATIONS

To advance dialogue about Aboriginal peoples' health, occupational therapists must engage in exploration of their profession's underlying theoretical concepts or risk participating in the perpetuation of health inequities for already at-risk populations.

Trends in cause specific mortality across occupations in Japanese men of working age during period of economic stagnation, 1980-2005: retrospective cohort study

OBJECTIVE

To assess the temporal trends in occupation specific all causes and cause specific mortality in Japan between 1980 and 2005.

DESIGN

Longitudinal analysis of individual death certificates by last occupation before death. Data on population by age and occupation were derived from the population census.

SETTING

Government records, Japan.

PARTICIPANTS

Men aged 30-59.

MAIN OUTCOME MEASURES

Age standardised mortality rate for all causes, all cancers, cerebrovascular disease, ischaemic heart disease, unintentional injuries, and suicide.

RESULTS

Age standardised mortality rates for all causes and for the four leading causes of death (cancers, ischaemic heart disease, cerebrovascular disease, and unintentional injuries) steadily decreased from 1980 to 2005 among all occupations except for management and professional workers, for whom rates began to rise in the late 1990s (P<0.001). During the study period, the mortality rate was lowest in other occupations such as production/labour, clerical, and sales workers, although overall variability of the age standardised mortality rate across occupations widened. The rate for suicide rapidly increased since the late 1990s, with the greatest increase being among management and professional workers.

CONCLUSIONS

Occupational patterns in cause specific mortality changed dramatically in Japan during the period of its economic stagnation and resulted in the reversal of occupational patterns in mortality that have been well established in western countries. A significant negative effect on the health of management and professional workers rather than clerks and blue collar workers could be because of increased job demands and more stressful work environments and could have eliminated or even reversed the health inequality across occupations that had existed previously.

Social and geographic inequalities in premature adult mortality in Japan: a multilevel observational study from 1970 to 2005

OBJECTIVES

To examine trends in social and geographic inequalities in all-cause premature adult mortality in Japan.

DESIGN

Observational study of the vital statistics and the census data.

SETTING

Japan.

PARTICIPANTS

Entire population aged 25 years or older and less than 65 years in 1970, 1975, 1980, 1985, 1990, 1995, 2000 and 2005. The total number of decedents was 984 022 and 532 223 in men and women, respectively.

MAIN OUTCOME MEASURES

For each sex, ORs and 95% CIs for mortality were estimated by using multilevel logistic regression models with 'cells' (cross-tabulated by age and occupation) at level 1, 8 years at level 2 and 47 prefectures at level 3. The prefecture-level variance was used as an estimate of geographic inequalities of mortality.

RESULTS

Adjusting for age and time-trends, compared with production process and related workers, ORs ranged from 0.97 (95% CI 0.96 to 0.98) among administrative and managerial workers to 2.22 (95% CI 2.19 to 2.24) among service workers in men. By contrast, in women, the lowest odds for mortality was observed among production process and related workers (reference), while the highest OR was 12.22 (95% CI 11.40 to 13.10) among security workers. The degree of occupational inequality increased in both sexes. Higher occupational groups did not experience reductions in mortality throughout the period and was overtaken by lower occupational groups in the early 1990s, among men. Conditional on individual age and occupation, overall geographic inequalities of mortality were relatively small in both sexes; the ORs ranged from 0.87 (Okinawa) to 1.13 (Aomori) for men and from 0.84 (Kanagawa) to 1.11 (Kagoshima) for women, even though there is a suggestion of increasing inequalities across prefectures since 1995 in both sexes.

CONCLUSIONS

The present findings suggest that both social and geographic inequalities in all-cause mortality have increased in Japan during the last 3 decades.

What has made the population of Japan healthy?

People in Japan have the longest life expectancy at birth in the world. Here, we compile the best available evidence about population health in Japan to investigate what has made the Japanese people healthy in the past 50 years. The Japanese population achieved longevity in a fairly short time through a rapid reduction in mortality rates for communicable diseases from the 1950s to the early 1960s, followed by a large reduction in stroke mortality rates. Japan had moderate mortality rates for non-communicable diseases, with the exception of stroke, in the 1950s. The improvement in population health continued after the mid-1960s through the implementation of primary and secondary preventive community public health measures for adult mortality from non-communicable diseases and an increased use of advanced medical technologies through the universal insurance scheme. Reduction in health inequalities with improved average population health was partly attributable to equal educational opportunities and financial access to care. With the achievement of success during the health transition since World War 2, Japan now needs to tackle major health challenges that are emanating from a rapidly ageing population, causes that are not amenable to health technologies, and the effects of increasing social disparities to sustain the improvement in population health.

The relationship between social capital and self-rated health in a Japanese population: a multilevel analysis

OBJECTIVE

The aim of this study was to use a multilevel analysis to examine whether cognitive and structural dimensions of regional social capital were associated with individual health outcomes after adjusting for compositional factors.

METHODS

Data from the Japanese General Social Surveys project, a nationwide study with a two-stage stratified random sampling method conducted in 2000, 2001, 2002, 2005, and 2006, were aggregated and used for the multilevel analysis (n = 11,702). We examined whether both cognitive and structural aspects of social capital (social trust, neighborhood safety, and social participation) were associated with the self-rated health (SRH) of residents from 118 regions after adjustment for compositional factors.

RESULTS

Social trust and existing neighborhood safety were negatively associated with poor SRH, whereas the effect of social participation was not significant. Social trust was still negatively associated with poor SRH after adjusting for individual demographic factors and socioeconomic status (p = 0.001). In contrast, neighborhood safety and social participation did not reach significance after adjusting for compositional factors.

CONCLUSION

Based on the results of this study, social trust was associated with health outcomes. Further study is needed to clarify the path linking regional trust in others to individual health outcomes in the Japanese population.

Cohort profile: the ages 2003 cohort study in Aichi, Japan

Background

The longevity of Japanese is thought to be associated with psychosocial factors such as sense of coherence, social support, and social capital. However, the actual factors responsible and the extent of their contribution to individual health status are not known.

Methods

The Aichi Gerontological Evaluation Study (AGES) 2003 Cohort Study is a prospective cohort study of community-dwelling, activities of daily living-independent people aged 65 or older living in 6 municipalities in Chita peninsula, Aichi Prefecture, Japan. Information on psychosocial factors and other individual- and community-level factors was collected in the second half of 2003 using a baseline questionnaire. Vital status and physical and cognitive decline have been followed using data derived from long-term care insurance certification. Geographical information on the study participants was also obtained.

Results

A total of 13 310 (6508 men; 6802 women) study participants were registered in the study. For an interim report, we followed the cohort for 48 months, yielding 24 753 person-years of observation among men and 26 456 person-years among women.

Conclusions

The AGES 2003 Cohort Study provides useful evidence for research in social epidemiology, gerontology, and health services.

Economic recession and health inequalities in Japan: analysis with a national sample, 1986-2001

OBJECTIVE

Little is known about whether economic crises widen health inequalities. Japan experienced more than 10 years of economic recession beginning in the 1990s. The question of whether socioeconomic-based inequality in self-rated health widened after the economic crisis was examined.

DESIGN, SETTING AND PARTICIPANTS

Repeated cross-sectional survey design. Two pooled datasets from 1986 and 1989 and from 1998 and 2001 were analysed separately, and temporal change was examined. The study took place in Japan among the working-age population (20-60 years old). The two surveys consisted of 168 801 and 150 016 people, respectively, with about an 80% response rate.

RESULTS

The absolute percentages of people reporting poor health declined across all socioeconomic statuses following the crisis. However, after controlling for confounding factors, the odds ratio (OR) for poor self-rated health (95% confidence intervals) among middle-class non-manual workers (clerical/sales/service workers) compared with the highest class workers (managers/administrators) was 1.02 (0.92 to 1.14) before the crisis but increased to 1.14 (1.02 to 1.29) after the crisis (p for temporal change = 0.02). The association was stronger among males. The adjusted ORs among professional workers and young female homemakers also marginally increased over time. Unemployed people were twice as likely to report poor health compared with the highest class workers throughout the period. Self-rated health of people with middle to higher incomes deteriorated in relative terms following the crisis compared with that of lower income people.

CONCLUSIONS

Self-rated health improved in absolute terms for all occupational groups even after the economic recession. However, the relative disparity increased between the top and middle occupational groups in men.

Factors Associated with Body Mass Index(BMI) Among Older Adults: A Comparison Study of the U.S., Japan, and Korea

This study examined BMI distributions among older adults in three different countries: the U.S., Japan, and Korea. The paper also explored differences in the factors predicting BMI in the three countries using three data sets: the U.S. Longitudinal Study of Aging (LSOA II, 8,589 persons), the Nihon University Japanese Longitudinal Study of Aging (NUJLSOA, 2,888 persons), and the Korean Longitudinal Study of Ageing (KLoSA, 2,397 persons). Descriptive analysis and multiple regression were performed. Japanese older adults were somewhat lighter than Koreans with fewer people at the upper end of the BMI distribution. Distributions of BMI among both Koreans and Japanese are shifted leftward relative to Americans. There is less dispersion in the distribution of BMI for Koreans and Japanese than among Americans. The association between socioeconomic variables and BMI is stronger in the U.S. and Japan than in Korea. Demographic variables are strong predictors of BMI in Korea. In Japan, all health behaviors have significant effects on BMI. It is concluded that the relationships between behavioral, demographical, and socioeconomic factors and BMI are not the same across countries. Results have policy implications for the involvement of health practitioners in helping older adults to control weight.

A tale of two countries--the United States and Japan: are differences in health due to differences in overweight?

Background

Despite similar standards of living and health care systems for older persons, there are marked differences in the relative health of the elderly populations in the United States (US) and Japan. We explore the association of overweight and obesity with these health disparities.

Methods

Data on older adults from the US National Health Interview Survey (1994) and the Longitudinal Study of Aging II (1994) were compared to similar data from the 1999-2001 Nihon University Japanese Longitudinal Study of Aging. Regression analyses for the 2 countries were conducted to examine the correlates of being overweight and obese, and the relationships of overweight and obesity with activities of daily living functioning, heart disease, arthritis, and diabetes.

Results

The prevalence of overweight and obesity is higher in the US than in Japan, as is the prevalence of heart disease, diabetes, arthritis, and functioning problems. Education level and marital status are predictors of overweight for older Americans but not for older Japanese people. Health behaviors affect weight in all groups. The prevalence of functioning problems and disease are more likely to be associated with being overweight in US men and women than in Japanese women, and are not associated with being overweight in Japanese men.

Conclusion

Despite similar standards of living and health care systems for older persons, the conditions associated with poor health differ in the US and Japan. Being overweight or obese appears to be related to more functioning problems and arthritis in the US than in Japan.