Gender difference in the association between social support and metabolic syndrome in Japan: the 'enkai' effect?

Association between workplace social capital and systolic blood pressure among 23 173 workers at 367 small-sized and medium-sized enterprises in Japan: a cross-sectional study

OBJECTIVES

Social capital (SC) has been shown to be inversely associated with elevated blood pressure. While SC in the workplace may also be associated with blood pressure, it has not been extensively studied. We aimed to investigate the association between workplace SC and systolic blood pressure (SBP).

DESIGN

A cross-sectional study.

SETTING

367 small-sized and medium-sized companies in Japan.

PARTICIPANTS

A total of 23 173 participants (15 991 males and 7182 females) aged ≥18 years.

EXPOSURE OF INTEREST

SC was assessed using individual responses to eight 4-point Likert questions used in the Brief Job Stress Questionnaire. Workplace SC was assessed as the mean of individual-level responses to the SC questions from those working in the same company.

OUTCOME MEASURE

Systolic blood pressure (SBP) RESULTS: A multilevel linear regression model revealed that higher workplace-level SC was linked with lower SBP (coef.=-0.53 per 1SD increment in workplace SC, 95% CI=-1.02 to -0.05) among females in the age-adjusted model, which remained statistically significant after adjusting for other covariates. After adjusting for individual-level SC, this association was attenuated and became non-significant (coef.=-0.41, 95% CI=-0.87 to 0.05), while individual-level SC was inversely associated with SBP (coef.=-0.43, 95% CI=-0.73 to -0.13). Among males, we did not find any evidence of significant inverse associations either in relation to workplace SC (coef.=-0.12, 95% CI=-0.46 to 0.21) or individual-level SC (coef.=0.19, 95% CI=-0.01 to 0.39).

CONCLUSIONS

Our study findings suggested that workplace-level SC can affect SBP differently by sex.

Risk Factors for Alcohol Consumption after Starting Assisted Reproductive Technology Treatment among Japanese Women: Japan-Female Employment and Mental Health in Assisted Reproductive Technology (J-FEMA) Study

AIMS

To determine the association between drinking habits and social factors among women undergoing assisted reproductive technology (ART) treatment in Japan.

METHODS

The study participants who provided answers for the questionnaire concerning alcohol consumption were 1017 female patients undergoing ART treatment were enrolled in the Japan-Female Employment and Mental Health in assisted reproductive technology (J-FEMA) study between August and December 2018. Patient characteristics, including demographic, clinical, and socioeconomic status, were assessed using a self-administered questionnaire which was distributed only once during the period, regardless of their first or follow-up examination. We defined current drinkers who drank ≥46 g of ethanol per week as the habitual drinking group. The risk factors for habitual drinking were analyzed using multivariable-adjusted logistic regression.

RESULTS

The proportion of habitual drinkers was 15.5% in this study population. The multivariable-adjusted odds ratios (95% confidence interval) for habitual drinking were 2.27 (0.99-5.21) for women aged ≥35 years versus those <35 years, 4.26 (1.98-9.16) for women having partners who currently drink compared to those with partners without current drinking, 1.84 (1.08-3.12) for women without a history of childbirth versus those with, and 1.77 (1.00-3.14) for working women compared with those not working.

CONCLUSIONS

In our study, habitual drinking among women undergoing ART treatment was significantly associated with older age, no history of childbirth, partner's current drinking status, and working.

Loneliness and risk for cardiovascular disease in the United States and Japan: The effects of nationality, collectivism, and gender

RATIONALE

Loneliness is a global concern associated with adverse effects on cardiovascular disease (CVD) that may differ by nationality, collectivism, and gender.

OBJECTIVE

This study examined whether associations between loneliness and CVD indicators (e.g., metabolic dysregulation [MetD], inflammation, sleep dysfunction) would vary by nationality, collectivism, and gender. We predicted that loneliness would be associated with poorer CVD values in (1) Japan than the United States (U.S.), (2) in individuals higher rather than lower in collectivism, and (3) our exploratory hypotheses about gender were that loneliness would interact with gender to be associated with differential CVD indicators in the U.S. versus Japan.

METHODS

Participants (aged 36 to 78) from the MIDUS Refresher Biomarker (n = 644) and the MIDJA 2 Biomarker studies (n = 293) completed questionnaires, bloodwork, and a physical exam. U.S. participants were from multiple cities, and Japanese participants were from Tokyo. Loneliness was measured via responses to the question, "How often in the past week did you feel lonely?" Logistic regression and path analyses using structural equation modeling determined individual differences in loneliness, whether loneliness predicted CVD indicators, and whether nationality, collectivism, and gender moderated these associations.

RESULTS

Loneliness was prevalent in the U.S. (25.39%) and Japan (20.82%). Unexpectedly, Japanese adults reported less collectivism than U.S. adults. We found significant interactions of (1) nationality and gender on MetD and inflammation, (2) gender and loneliness on sleep dysfunction, and (3) nationality and loneliness on MetD. Loneliness was associated with greater MetD in the U.S. but not in Japan.

CONCLUSIONS

Cultural influences on loneliness contradicted expectations and suggested caution when equating nationality with cultural values. Our Japanese sample was from Tokyo, which may have lower collectivism than rural Japanese regions. We recommend future studies consider geographic location when examining associations between loneliness, collectivism, and CVD.

Alcohol's harm to others in Japan: Different rates for different relationships to the drinker in a 2018 national survey

INTRODUCTION

No study in Japan has investigated alcohol's harm to others (AHTO). Therefore, this study aimed to reveal the situation of AHTO in Japan and examine the factors associated with it based on the relationship with the drinker.

METHODS

A cross-sectional population-based survey was performed in 2018 with 2121 men and 2507 women. Respondents were asked questions about factors such as verbal or physical aggression, being forced to drink alcohol, sexual harassment and their relationship with the drinker. Binomial logistic regression was performed to quantify the associations of AHTO with participants' socio-demographic status and drinking patterns.

RESULTS

The lifetime experience of AHTO was 24.7% for men and 19.3% for women. AHTO from the father and co-workers were the most common in and outside the home, respectively. The frequency of AHTO from the spouse or co-workers showed no significant difference for abstainers and drinkers. However, AHTO from the father was more commonly reported among drinkers and those with Alcohol Use Disorders Identification Test scores ≥8 points than abstainers. Of those who experienced AHTO, 24.5% of men and 27.6% of women, and 6.1% of men and 12.9% of women were profoundly affected by it in and outside the home, respectively.

DISCUSSION AND CONCLUSIONS

One in five Japanese residents experienced AHTO in their life, and the characteristics associated with AHTO differed according to the affected individual's relationship with the drinker. Continued monitoring of AHTO and measures aimed at reducing alcohol-related harm that include AHTO should be promoted.

Clustering of health behaviors among Japanese adults and their association with socio-demographics and happiness

Background

Scholars have associated happiness with health behaviors, which co-occur and exert synergistic effects. Therefore, identifying clusters of health behaviors and their effect on happiness can contribute to the development of strategies for promoting happiness and improving health behaviors.

Aim

This study aimed to examine clusters of health behaviors and their associations with socio-demographics and with happiness among Japanese adults.

Methods

This study used data from the Japanese Household Panel Survey and the Keio Household Panel Survey. Questionnaires were distributed to 4,993 households out of which 1,554 responses were analyzed (participants aged 27−65 years). The survey included health behaviors (alcohol consumption, smoking, vegetable and fruit consumption, breakfast-eating habits, and physical activities), happiness, and socio-demographics. Latent class analysis was conducted to identify the clusters, whereas latent regression was employed to investigate socio-demographics related to the clusters. Logistic regression analysis was conducted to examine the relation between happiness and the clusters.

Results

Two health behavior clusters were identified: Cluster 1 (low substance use and good dietary habit; n = 817; 52.3%) and Cluster 2 (high alcohol, poor nutrition, and inactive; n = 737; 47.7%). Latent regression analysis indicated that all socio-demographics, barring socioeconomic status, were significantly associated with the clusters. The “low substance use and good dietary habit” cluster was significantly related with higher odds of happiness (odds ratio = 1.425, 95% confidence interval = 1.146−1.772, p = 0.001).

Conclusions

This study identified health behavior clusters among Japanese adults and established the association between the “low substance use and good dietary habit” cluster and high levels of happiness. However, the causality of the relationship between health behavior and happiness remains unclear, which highlights the need for further research to elucidate the underlying mechanisms.

Maternal personality and alcohol use during pregnancy in Japan: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

BACKGROUND

Studies on associations between maternal personality and alcohol use have examined only one time point during pregnancy in Western countries. We aimed to examine the association between maternal personality and alcohol use in early and middle pregnancy in Japan.

METHODS

We analyzed data from 17,144 pregnant women in Japan who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study from 2013 to 2017. Personality was assessed using the short-form Eysenck Personality Questionnaire-Revised. Women were dichotomized as current drinkers or non-drinkers in both early and middle pregnancy. Odds ratios (ORs) and 95% confidence intervals (CIs) for alcohol use in early and middle pregnancy and continued alcohol use between early and middle pregnancy were calculated for 1 standard deviation increase in each personality scale, adjusted for age, as well as education, work status, fertility treatment, and parity.

RESULTS

Higher extraversion scores were associated with alcohol use in early (OR, 1.16; 95% CI, 1.12-1.20) and middle pregnancy (OR, 1.17; 95% CI, 1.10-1.25). Higher psychoticism scores were associated with continued alcohol use into middle pregnancy (OR, 1.07; 95% CI, 1.01-1.14) and alcohol use in middle pregnancy (OR, 1.07; 95% CI, 1.02-1.13). Neuroticism was not associated with alcohol use in early or middle pregnancy. Lower lie was associated with alcohol use in early (OR, 0.95; 95% CI, 0.91-0.98), but not in middle pregnancy.

CONCLUSIONS

Different personality scales are associated with alcohol use at different points during pregnancy.

The Forgotten Ones: Crafting for Meaning and for Affiliation in the Context of Finnish and Japanese Employees' Off-Job Lives

In an intensifying working life, it is important for employees to proactively shape their lives beyond work to create opportunities for satisfying personal needs. These efforts can be beneficial for creating and sustaining well-being in terms of vitality. In this study, we focused on off-job crafting (OJC) for meaning and OJC for affiliation, conceptualized as proactive changes in off-job life with the aim of increasing satisfaction of needs for meaning and affiliation, among employees in Finland and Japan, two countries with disparate cultural values. We examined longitudinal within-person relationships between the two OJC dimensions and vitality, as well as the relationships between OJC and contextual variables, such as age and gender. We conducted a longitudinal study over 6 months with three measurement points. A total of 578 Finnish and 228 Japanese employees participated in the study. Hypotheses were tested with latent growth analysis. Increases in OJC for meaning and for affiliation were mostly positively related to increases in vitality over time in both countries. In Finland, age was positively related to OJC for meaning. In Japan, age was negatively related to OJC for meaning, but the female gender was positively related to OJC for affiliation. Focusing on increasing meaning and affiliation in off-job life can be beneficial strategies for employees to feel positively energized. The role of contextual variables and culture in OJC should be examined further in future studies.

Associations of education and work status with alcohol use and cessation among pregnant women in Japan: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

Background

There is inconsistent evidence on the associations of education and work status with alcohol use during pregnancy. Our aim was to examine the associations of education and work status with alcohol use and alcohol cessation during pregnancy in Japan.

Methods

Data were analyzed from 11,839 pregnant women who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study from 2013 to 2017 in Japan. Women were dichotomized as current drinkers or non-drinkers in both early and middle pregnancy. Alcohol cessation was defined as alcohol use in early pregnancy, but not in middle pregnancy. Multivariable log-binomial regression analyses were conducted to examine associations of education and work status with alcohol use in early and middle pregnancy and alcohol cessation, adjusted for age and income. The prevalence ratios (PRs) and 95% confidence intervals (CIs) were calculated by work status and education.

Results

The prevalence of alcohol use in early and middle pregnancy was 20.9 and 6.4%, respectively. Higher education was associated with alcohol use in early pregnancy both among working and non-working women; the PRs of university education or higher compared with high school education or lower were 1.62 (95% CI, 1.34–1.96) and 1.29 (95% CI, 1.16–1.45), respectively. Higher education was associated with alcohol cessation during pregnancy among working women; the corresponding PR was 1.09 (95% CI, 1.01–1.17). Working was associated with alcohol use in early and middle pregnancy. Working was associated with a decreased probability of alcohol cessation among women with lower education but with an increased probability of alcohol cessation among women with higher education; the PRs of working compared with not working were 0.91 (95% CI, 0.82–1.00) and 1.10 (95% CI, 1.00–1.20), respectively.

Conclusions

Women with higher education were more likely to consume alcohol in early pregnancy and to cease alcohol use between early and middle pregnancy, especially working women. Working women were more likely to consume alcohol throughout pregnancy. Working women with lower education were less likely to cease alcohol use, whereas working women with higher education were more likely to cease alcohol use between early and middle pregnancy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11461-w.

Social disconnection and metabolic syndrome score among Cambodian Americans with depression

AIMS

Migrants experience social disconnection and also have high risk for metabolic syndrome (MetS). This study explored associations of social alienation, social isolation, and social support with MetS among Cambodian Americans.

METHODS

We conducted secondary data analysis on baseline assessments from a diabetes prevention trial for Cambodian Americans with depression and high risk for diabetes. Participants were aged 35-75, Cambodian or Cambodian-American, Khmer speaking, lived in Cambodia during the Pol Pot regime, lived in the northeastern U.S. at the time of study, endorsed elevated risk factors for diabetes and met criteria for depression by medication for depression and/or elevated depressive symptoms. They completed surveys and provided anthropometric and blood pressure measurements and fasting blood samples.

RESULTS

In multiple linear regressions, greater social alienation was associated with increased risk for MetS. The social alienation-MetS association was stronger in men than women. Associations were not better accounted for by crude indicators of social isolation such as marital status, living alone, and number of people in the household. Social support was not associated with MetS and did not buffer the deleterious association between social alienation and MetS.

CONCLUSIONS

Decreasing social alienation may mitigate risk for MetS among migrant populations.

Smoking and drinking among patients with mental disorders: Evidence from a nationally representative Japanese survey

BACKGROUND

No studies to date have addressed the association of mental disorder with smoking and drinking behaviors independent of anxiety and depressive symptoms. We therefore examined this association, stratified by age and sex, to determine the target population for behavioral modification in Japan.

METHODS

We analyzed data from participants aged 20-79 years without hospitalized or institutionalized status who participated in the nationwide Comprehensive Survey of Living Conditions conducted in 2016. Prevalence ratios (PRs) for current smoking, heavy daily smoking (>20 cigarettes per day), at-risk drinking (>100 g alcohol per week), and heavy drinking (>350 g) were calculated with adjustment for potential confounders. After stratification by age (20-39, 40-64, and 65-79 years) and sex, prevalence and PRs were calculated using propensity scores.

RESULTS

From among 340,194 participants, 8275 (2.4%) had mental disorder. Presence of mental disorder was significantly associated with current smoking (PR=1.18, 95%CI=1.12-1.23) and heavy daily smoking (PR=1.35, 95%CI=1.21-1.50) and inversely associated with at-risk drinking (PR=0.70, 95%CI=0.66-0.75). PRs for smoking behavior were higher in women than in men and in younger adults than in the other age groups. They were particularly high in younger women (PR=1.67 for current smokers and PR=2.17 for heavy daily smokers).

LIMITATIONS

Our findings were obtained from a cross-sectional study.

CONCLUSION

This is the first evidence that the association of mental disorder with smoking behavior is independent of anxiety and depressive symptoms. Our results indicate the need for tailored behavioral modification interventions for young people with mental disorders in Japan, particularly young women.

Risk Factors of Metabolic Syndrome in Community-Dwelling People with Schizophrenia

This study investigated the prevalence and risk factors of metabolic syndrome in 100 community-dwelling people with schizophrenia registered in mental health facilities in Seoul, Korea. This study was conducted between 12 September and 15 November 2019. This study used a cross-sectional descriptive design. The data included were general and disease-related characteristics, diagnostic tests for metabolic syndrome, lifestyles, depression, and social support. The analysis of collected data was done by using the SPSS 24.0 program. The prevalence of metabolic syndrome was 42.0%. Higher body mass index (odds ratio [OR] = 1.60, 95% CI = 1.16–2.18, p = 0.004), and depression (OR = 1.22, 95% CI = 1.06–1.42, p = 0.008) were associated with higher risks of metabolic syndrome, while physical activity and weight control (OR = 0.71, 95% CI = 0.54–0.94, p = 0.018), dietary habits (OR = 0.72, 95% CI = 0.54–0.93, p = 0.011), and medication and health management (OR = 0.52, 95% CI = 0.31–0.86, p = 0.012) were associated with lower risks. Mental health care nurses need to recognize the high prevalence of metabolic syndrome in people with schizophrenia in the community and provide differentiated, customized lifestyle improvement programs based on the body mass index and depression status of each person with schizophrenia. Furthermore, comprehensive lifestyle improvement programs and health examination services that people with schizophrenia can easily adhere to should be developed.

Does loneliness 'get under the skin'? Associations of loneliness with subsequent change in inflammatory and metabolic markers

Objectives: To expand existing knowledge about the associations of late-life loneliness with subsequent change in inflammation as well as with metabolic dysregulation, using national representative longitudinal data. The current analysis also explores age, gender, and race differences in these pre-disease pathways. Method: The analysis is based on data from the 2005-06 and 2010-11 waves of the National Social Life, Health, and Aging Project (NSHAP)-a longitudinal survey conducted among a representative sample of community-dwelling Americans aged 57-85. Adjusted logistic regression models were used to examine associations of loneliness with changes in C-reactive protein (CRP), Glycated hemoglobin (HbA1c), Body Mass Index (BMI), Waist Circumference (WC), and metabolic burden. Results: Loneliness was found to be associated with a change for the worse in most of the metabolic bio-markers. Specifically, lonely older adults had 39%-71% higher odds of developing prospective risk levels in three out of the four metabolic bio-markers that were measured: HbA1c, BMI, and metabolic burden. Salient differences by race were found in this regard. Whereas loneliness was not significantly associated with HbA1c risk levels and BMI among the Whites, the prospective risk of high HbA1c was more than five times greater and the risk of high BMI scores was three times greater among Hispanics who experienced loneliness than among the not-lonely Hispanic group. Conclusions: The robust impact of loneliness on prospective changes for the worse in levels of various metabolic bio-markers that are closely associated with morbidity highlights the need for prevention, coping with, and reducing loneliness.

Loneliness as a risk factor for metabolic syndrome: results from the HUNT study

Objective

Metabolic syndrome (MetS) includes hyperglycaemia, hypertension, central adiposity, elevated triglyceride levels and low levels of high-density lipoprotein cholesterol. All factors are identified as risk factors for cardiovascular disease and mortality. This longitudinal study examined whether loneliness, which has been shown to predict a range of negative health outcomes, increases the risk for MetS.

Methods

We used data from ‘the Nord-Trøndelag Health Study’ (HUNT) which is a large longitudinal health study based on a Mid-Norway county population (n=26 990). Self-reports, physical examinations and blood samples were analysed to evaluate the associations between loneliness and incidents of MetS after 10 years (follow-up survey conducted during 2006–2008). We also investigated the role of depression as a potential mediating factor.

Results

Individuals who reported higher levels of loneliness had a higher odds for MetS (adjusted OR 1.09 (95% CI 1.02 to 1.16); p=0.007). This effect was mediated through depression.

Conclusions

Findings suggest that loneliness may be an important factor that increases the risk for MetS. The effect of loneliness on MetS is mediated through depressive symptoms. Reducing loneliness may help prevent the incidence of MetS and related diseases.

Associations of education and income with heavy drinking and problem drinking among men: evidence from a population-based study in Japan

Background

Some studies in Western countries have suggested that education and income are differentially associated with different drinking patterns. This study aimed to examine the associations of education and income with heavy drinking and problem drinking among community-dwelling Japanese men.

Methods

A questionnaire survey was conducted in metropolitan areas in Japan from 2010 to 2011 among residents aged 25 to 50 years; valid responses were received from 2004 men. Drinking patterns were categorized as non-to-moderate drinking, non-problematic heavy drinking, and problem drinking. Multiple logistic regression analyses were conducted to determine whether educational attainment or income was associated with drinking patterns, after adjustment for age, marital status, working status, income/education, self-rated health, and psychological distress.

Results

The study population included 84.4% non-to-moderate drinkers, 8.9% non-problematic heavy drinkers, and 6.7% problem drinkers. Lower educational attainment (high school or less) was significantly associated with increased risks of both non-problematic heavy drinking (odds ratio [OR], 1.80; 95% confidence interval [CI], 1.21–2.67) and problem drinking (OR, 2.06; 95% CI, 1.34–3.16), compared with university education or higher. Lower income (lowest tertile) was significantly associated with a lower risk of non-problematic heavy drinking (OR, 0.66; 95% CI, 0.43–1.00), but not of problem drinking (OR, 0.80; 95% CI, 0.50–1.30), compared with the highest income tertile.

Conclusions

These findings indicate that education and income are differentially associated with alcohol drinking patterns among community-dwelling Japanese men.

Associations of non-standard employment with cardiovascular risk factors: findings from nationwide cross-sectional studies in Japan

This study aimed to examine the cross-sectional association of non-standard employment with cardiovascular disease risk factors. Five yr of data from the Comprehensive Survey of Living Conditions and National Health and Nutritional Survey were combined. We used logistic regression to examine the association of employment contract (non-standard [part-time, dispatched, or contract] vs. standard [full-time and permanent]) with eight cardiovascular disease risk factors among 1,636 men and 2,067 women aged 40-60 yr. There were significant associations between non-standard employment and cardiovascular disease risk factors such as current smoking among men (odds ratio [OR] 1.39; 95% confidential interval [CI], 1.13-1.86) and diabetes among women (OR 1.83; 95% CI, 1.10-3.09). Non-standard employment was associated with a few cardiovascular disease risk factors in this middle-aged cohort in Japan.

Examples of sex/gender sensitivity in epidemiological research: results of an evaluation of original articles published in JECH 2006-2014

BACKGROUND

During the last decades, sex and gender biases have been identified in various areas of biomedical and public health research, leading to compromised validity of research findings. As a response, methodological requirements were developed but these are rarely translated into research practice. The aim of this study is to provide good practice examples of sex/gender sensitive health research.

METHODS

We conducted a systematic search of research articles published in JECH between 2006 and 2014. An instrument was constructed to evaluate sex/gender sensitivity in four stages of the research process (background, study design, statistical analysis, discussion).

RESULTS

In total, 37 articles covering diverse topics were included. Thereof, 22 were evaluated as good practice example in at least one stage; two articles achieved highest ratings across all stages. Good examples of the background referred to available knowledge on sex/gender differences and sex/gender informed theoretical frameworks. Related to the study design, good examples calculated sample sizes to be able to detect sex/gender differences, selected sex/gender sensitive outcome/exposure indicators, or chose different cut-off values for male and female participants. Good examples of statistical analyses used interaction terms with sex/gender or different shapes of the estimated relationship for men and women. Examples of good discussions interpreted their findings related to social and biological explanatory models or questioned the statistical methods used to detect sex/gender differences.

CONCLUSIONS

The identified good practice examples may inspire researchers to critically reflect on the relevance of sex/gender issues of their studies and help them to translate methodological recommendations of sex/gender sensitivity into research practice.

Association between Social Relationship and Glycemic Control among Older Japanese: JAGES Cross-Sectional Study

Aim

The present study examined whether social support, informal socializing and social participation are associated with glycemic control in older people.

Methods

Data for this population-based cross-sectional study was obtained from the Japan Gerontological Evaluation Study (JAGES) 2010 linked to the annual health check-up data in Japan. We analyzed 9,554 individuals aged ≥65 years without the certification of needed long-term care. Multivariate logistic regression models were used to assess the effect of social support, informal socializing and social participations on glycemic control. The outcome measure was HbA1c ≥8.4%.

Results

1.3% of the participants had a level of HbA1c over 8.4%. Better glycemic control was significantly associated with meeting with friends one to four times per month (odds ratio [OR] 0.51, 95% confidence interval [CI]0.30–0.89, compared to meeting with friends a few times per year or less) and participation in sports groups (OR 0.50, 95% CI 0.26–0.97) even after adjusting for other variables. Meeting with friends more than twice per week, receiving social support, and being married were not associated with better control of diabetes.

Conclusions

Meeting with friends occasionally is associated with better glycemic control among older people.

Influence of socioeconomic status on the association between body mass index and cause-specific mortality among older Japanese adults: The AGES Cohort Study

OBJECTIVE

Many studies have suggested a U-shaped curve for the association between body size and mortality risks, i.e., mortality risks increase in those who are both overweight and underweight. The strength of the associations may vary according to socioeconomic statuses (SES), as they determine levels of access to healthcare and psychosocial stresses. We investigated the modifying effects of SES on the relationship between body mass index (BMI) and mortality.

METHOD

We used prospective cohort data of participants in the Aichi Gerontological Evaluation Study in 2003 (n=14,931), who were 65years or older and physically and cognitively independent at baseline, and residing in eight municipalities in Japan. Data on all-causes mortality and mortality from cancer, cardiovascular disease, and respiratory disease was obtained from municipal government registries.

RESULTS

Proportional hazard regression analyses showed that, among men, the associations between overweight (BMI≥25kg/m(2)) and higher mortality risks by any cause were stronger among lower income groups. Even adjusting for multiple confounding factors, hazard ratios (95% confidence intervals) for mortality by all causes among low income group (household income<1.5 million yen) were 1.96 (1.02-3.73) for overweight compared with BMIs between 23.0 and 24.9, whereas they were 0.94 (0.57-1.38) among men in high income group (income>3 million yen). The modifying effects of income were not marked among women.

CONCLUSION

Household income, which may directly reflect accessibility to healthcare and psychosocial stress among older Japanese men, may be an important modifying factor in the health risks attributable to overweight.

Individual social capital and survival: a population study with 5-year follow-up

Background

The concept of social capital has received increasing attention as a determinant of population survival, but its significance is uncertain. We examined the importance of social capital on survival in a population study while focusing on gender differences.

Methods

We used data from a Danish regional health survey with a five-year follow-up period, 2007–2012 (n = 9288, 53.5% men, 46.5% women). We investigated the association between social capital and all-cause mortality, performing separate analyses on a composite measure as well as four specific dimensions of social capital while controlling for covariates. Analyses were performed with Cox proportional hazard models by which hazard ratios and 95% confidence intervals were calculated.

Results

For women, higher levels of social capital were associated with lower all-cause mortality regardless of age, socioeconomic status, health, and health behaviour (HR = 0.586, 95% CI = 0.421-0.816) while no such association was found for men (HR = 0.949, 95% CI = 0.816-1.104). Analysing the specific dimensions of social capital, higher levels of trust and social network were significantly associated with lower all-cause mortality in women (HR = 0.827, 95% CI = 0.750-0.913 and HR = 0.832, 95% CI = 0.729-0.949, respectively). For men, strong social networks were associated with a higher risk of all-cause mortality (HR = 1.132, 95% CI = 1.017-1.260). Civic engagement had a similar effect for both men (HR = 0.848, 95% CI = 0.722-0.997) and women (HR = 0.848, 95% CI = 0.630-1.140).

Conclusions

We found differential effects of social capital in men compared to women. The predictive effects on all-cause mortality of four specific dimensions of social capital varied. Gender stratified analysis and the use of multiple indicators to measure social capital are thus warranted in future research.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-1025) contains supplementary material, which is available to authorized users.

The bright side and dark side of workplace social capital: opposing effects of gender on overweight among Japanese employees

Background

A growing number of studies have sought to examine the health associations of workplace social capital; however, evidence of associations with overweight is sparse. We examined the association between individual perceptions of workplace social capital and overweight among Japanese male and female employees.

Methodology/Principal Findings

We conducted a cross-sectional survey among full-time employees at a company in Osaka prefecture in February 2012. We used an 8-item measure to assess overall and sub-dimensions of workplace social capital, divided into tertiles. Of 1050 employees, 849 responded, and 750 (624 men and 126 women) could be linked to annual health check-up data in the analysis. Binomial logistic regression models were used to calculate odds ratios and 95% confidence intervals for overweight (body mass index: ≥25 kg/m², calculated from measured weight and height) separately for men and women. The prevalence of overweight was 24.5% among men and 14.3% among women. Among men, low levels of bonding and linking social capital in the workplace were associated with a nearly 2-fold risk of overweight compared to high corresponding dimensions of social capital when adjusted for age, sleep hours, physiological distress, and lifestyle. In contrast, among women we found lower overall and linking social capital to be associated with lower odds for overweight even after covariate adjustment. Subsequently, we used multinomial logistic regression analyses to assess the relationships between a 1 standard deviation (SD) decrease in mean social capital and odds of underweight/overweight relative to normal weight. Among men, a 1-SD decrease in overall, bonding, and linking social capital was significantly associated with higher odds of overweight, but not with underweight. Among women, no significant associations were found for either overweight or underweight.

Conclusions/Significance

We found opposite gender relationships between perceived low linking workplace social capital and overweight among Japanese employees.

Impact of social integration on metabolic functions: evidence from a nationally representative longitudinal study of US older adults

Background

Metabolic functions may operate as important biophysiological mechanisms through which social relationships affect health. It is unclear how social embeddedness or the lack thereof is related to risk of metabolic dysregulation. To fill this gap we tested the effects of social integration on metabolic functions over time in a nationally representative sample of older adults in the United States and examined population heterogeneity in the effects.

Methods

Using longitudinal data from 4,323 adults aged over 50 years in the Health and Retirement Study and latent growth curve models, we estimated the trajectories of social integration spanning five waves, 1998–2006, in relation to biomarkers of energy metabolism in 2006. We assessed social integration using a summary index of the number of social ties across five domains. We examined six biomarkers, including total cholesterol, high-density lipoprotein cholesterol, glycosylated hemoglobin, waist circumference, and systolic and diastolic blood pressure, and the summary index of the overall burden of metabolic dysregulation.

Results

High social integration predicted significantly lower risks of both individual and overall metabolic dysregulation. Specifically, adjusting for age, sex, race, and body mass index, having four to five social ties reduced the risks of abdominal obesity by 61% (odds ratio [OR] [95% confidence interval {CI}] = 0.39 [0.23, 0.67], p = .007), hypertension by 41% (OR [95% CI] = 0.59 [0.42, 0.84], p = .021), and the overall metabolic dysregulation by 46% (OR [95% CI] = 0.54 [0.40, 0.72], p < .001). The OR for the overall burden remained significant when adjusting for social, behavioral, and illness factors. In addition, stably high social integration had more potent metabolic impacts over time than changes therein. Such effects were consistent across subpopulations and more salient for the younger old (those under age 65), males, whites, and the socioeconomically disadvantaged.

Conclusions

This study addressed important challenges in previous research linking social integration to metabolic health by clarifying the nature and direction of the relationship as it applies to different objectively measured markers and population subgroups. It suggests additional psychosocial and biological pathways to consider in future research on the contributions of social deficits to disease etiology and old-age mortality.

A cross-sectional study of workplace social capital and blood pressure: a multilevel analysis at Japanese manufacturing companies

OBJECTIVES

We examined the contextual effect of workplace social capital on systolic blood pressure (SBP).

DESIGN

Cross-sectional.

SETTING

A conglomerate from 58 workplaces in Japan.

PARTICIPANTS

Of the 5844 workers at a Japanese conglomerate from 58 workplaces, 5368 were recruited. Individuals who received drugs for hypertension (n=531) and who lacked information on any variable (n=167) were excluded from the analyses, leaving 4735 individuals (3281 men and 1454 women) for inclusion.

PRIMARY AND SECONDARY OUTCOME MEASURES

Systolic blood pressure.

RESULTS

The contextual effect of workplace social capital on SBP was examined using a multilevel regression analysis with a random intercept. Coworker support had a contextual effect at the workplace level (coefficient=-1.97, p=0.043), while a lack of trust for coworkers (coefficient=0.27, p=0.039) and lack of helpfulness from coworkers were associated with SBP (coefficient=0.28, p=0.002).

CONCLUSIONS

The present study suggested that social capital at the workplace level has beneficial effects on SBP.

Social encounters in daily life and 2-year changes in metabolic risk factors in young women

Research shows that poor social ties increase risks of morbidity and mortality from cardiovascular disease (CVD). However, little is known about the nature of everyday social encounters that give rise to this association, or when in the course of development they begin to shape disease-relevant biological processes. In this study, 122 adolescent females recorded the qualities of their everyday social interactions using electronic diaries. At the same time we measured components of the metabolic syndrome, a precursor to CVD that includes central adiposity, high blood pressure, insulin resistance, and lipid dysregulation. Metabolic symptoms were reassessed 12 and 24 months later. Hierarchical linear modeling revealed an association between negative social interactions and metabolic symptom trajectories. To the extent that participants had more intense negative social encounters in daily life, they showed increasing scores on a composite indicator of metabolic risk over 2 years. This association was independent of a variety of potential confounders, and persisted when symptoms of depression and broader personality traits were controlled. There was no association between positive social encounters and metabolic risk trajectories. These findings suggest that even in otherwise healthy adolescents, abrasive social encounters may accelerate the progression of early stages of CVD.