Socioeconomic status and self-rated health of Japanese people, based on age, cohort, and period

Socioeconomic inequalities in self-rated health in Japan, 32 European countries and the United States: an international comparative study

AIMS

Japan is known as a country with low self-rated health despite high life expectancy. We compared socioeconomic inequalities in self-rated health in Japan with those in 32 European countries and the US using nationally representative samples.

METHODS

We analysed individual data from the Comprehensive Survey of Living Conditions (Japan), the European Union Statistics on Income and Living Conditions, and the Behavioral Risk Factor Surveillance System (US) in 2016. We used ordered logistic regression models with four ordinal categories of self-rated health as an outcome, and educational level or occupational class as independent variables, controlling for age.

RESULTS

In Japan, about half the population perceived their health as 'fair', which was much higher than in Europe (≈20-40%). The odds ratios of lower self-rated health among less educated men compared with more educated were 1.72 (95% confidence interval (CI) 1.61-1.85) in Japan, and ranged from 1.67 to 4.74 in Europe (pooled; 2.10 (95% CI 2.01-2.20)), and 6.65 (95% CI 6.22-7.12) in the US. The odds ratios of lower self-rated health among less educated women were 1.79 (95% CI 1.65-1.95) in Japan, and ranged from 1.89 to 5.30 in Europe (pooled; 2.43 (95% CI 2.33-2.54)), and 8.82 (95% CI 8.29-9.38) in the US. Socioeconomic inequalities were large when self-rated health was low for European countries, but Japan and the US did not follow the pattern.

CONCLUSIONS

Japan has similar socioeconomic gradient patterns to European countries for self-rated health, and our findings revealed smaller socioeconomic inequalities in self-rated health in Japan compared with those in western countries.

Multimorbidity patterns and the relation to self-rated health among older Japanese people: a nationwide cross-sectional study

OBJECTIVES

Classifying individuals into multimorbidity patterns can be useful to identify the target population with poorer clinical outcomes. Self-rated health (SRH) is one of the core outcomes in multimorbidity patients. Although studies have reported that multimorbidity is associated with poor SRH, whether certain patterns have stronger associations remains unknown. Therefore, this study aimed to identify the prevalence and patterns of multimorbidity and investigate the association between multimorbidity patterns and SRH in an older Japanese population.

DESIGN

Cross-sectional study.

SETTING

Data were obtained from the 2013 Comprehensive Survey of Living Conditions, a nationally representative survey of the general Japanese population.

PARTICIPANTS

This study mainly examined 23 730 participants aged ≥65 years who were not hospitalised or institutionalised.

PRIMARY OUTCOME MEASURE

Poor SRH was defined as choosing 'not very good' or 'bad' from five options: 'excellent', 'fairly good', 'average', 'not very good' and 'bad'.

RESULTS

The prevalence of multimorbidity was 40.9% and that of poor SRH was 23.8%. Three multimorbidity patterns were identified by exploratory factor analysis: (1) degenerative/mental health, (3) malignant/digestive/urological/haematological and (3) cardiovascular/metabolic. Multivariable modified Poisson regression analysis revealed that high malignant/digestive/urological/haematological, degenerative/mental health and cardiovascular/metabolic pattern scores, corresponding to the number of affected body systems in each pattern, were significantly associated with poor SRH (adjusted risk ratio (aRR)=1.68, 95% CI: 1.60 to 1.76; aRR=1.63, 95% CI: 1.58 to 1.69; and aRR=1.31, 95% CI: 1.26 to 1.36, respectively). When including the Kessler 6 score, a screening scale for psychological distress, in the analysis, the association between each multimorbidity pattern score and poor SRH decreased.

CONCLUSIONS

Malignant/digestive/urological/haematological and degenerative/mental health patterns may be associated with a high risk for poor SRH. Further research should focus on interventions to improve SRH in multimorbidity patients.

Relationship between occupational injury and gig work experience in Japanese workers during the COVID-19 pandemic: a cross-sectional internet survey

This study evaluated the relationship between occupational injury risk and gig work, which included the exchange of labor for money between individuals or companies via digital platforms. As Japan has experienced a severe economic decline during the coronavirus disease 2019 (COVID-19) pandemic, an increasing number of individuals have engaged in gig work. While few studies have evaluated occupational risks in gig work, several traffic accidents associated with food delivery gig work have been reported in the mass media. In this study, 18,317 individuals completed an internet survey that collected information pertaining to their involvement in gig work and experience of related occupational injuries; data regarding several confounding factors were also recorded. Multiple logistic regression analysis showed that workers involved in gig work had a greater risk of any minor occupational injuries (odds ratio, 3.68; 95% confidence interval, 3.02-4.49) and activity-limiting injuries (odds ratio, 9.11; 95% confidence interval, 7.03-11.8) than those not involved in gig work, after adjusting for age, sex, household income, lifestyle factors, and work-related factors. The results of this study indicate that gig workers are exposed to greater occupational hazards during the COVID-19 pandemic. Additional studies are warranted to clarify the causal mechanism for this relationship.

Trends and socioeconomic inequalities in self-rated health in Japan, 1986-2016

INTRODUCTION

Despite having very high life expectancy, Japan has relatively poor self-rated health, compared to other high-income countries. We studied trends and socioeconomic inequalities in self-rated health in Japan using nationally representative data.

METHODS

The Comprehensive Survey of Living Conditions was analyzed, every 3 years (n ≈ 0.6-0.8 million/year) from 1986 to 2016. Whereas previous studies dichotomized self-rated health as an outcome, we used four categories: very good, good, fair, and bad/very bad. Proportional odds ordinal logistic regression models are used, with ordinal scale self-rated health as an outcome, and age category, survey year and occupational class or educational level as independent variables.

RESULTS

In 2016, the age-adjusted percentages for self-rated health categorized as very good, good, fair, and bad/very bad, were 24.0, 17.1, 48.7, and 10.2% among working-age men, and 21.6, 17.5, 49.4, and 11.5% among working-age women, respectively. With 1986 as the reference year, the odds ratios (ORs) of less good self-rated health were lowest in 1995 (0.69; 95% Confidence Interval [95% CI]: 0.66-0.71 of working-age men), and highest in 2010 (1.23 [95% CI: 1.19-1.27]). The ORs of male, lower non-manual workers (compared to upper non-manual) increased from 1.12 (95% CI: 1.07-1.17) in 2010 to 1.20 (95% CI: 1.15-1.26) in 2016. Between 2010 and 2016, the ORs of working-age men with middle and low levels of education (compared to a high level of education) increased from 1.22 (95% CI: 1.18-1.27) to 1.34 (95% CI: 1.29-1.38), and from 1.47 (95% CI: 1.39-1.56) to 1.75 (95% CI: 1.63-1.88), respectively. The ORs of working-age women with middle and low levels of education also increased from 1.22 (95% CI: 1.17-1.28) to 1.32 (95% CI: 1.26-1.37), and from 1.74 (95% CI: 1.61-1.88) to 2.03 (95% CI: 1.87-2.21) during the same period.

CONCLUSION

Japan has the unique feature that approximately 50% of the survey respondents rated their self-rated health as fair, but with important variations over time and between socioeconomic groups. In-depth studies of the role of socioeconomic conditions may shed light on the reasons for the high prevalence of poor self-rated health in Japan.

Lumbar Spinal Stenosis and Potential Management With Prostaglandin E1 Analogs

ABSTRACT

Lumbar spinal stenosis is one of the most commonly diagnosed spinal disorders worldwide and remains a major cause for surgery in older adults. Lumbar spinal stenosis is clinically defined as a progressive degenerative disorder with low back pain and associated neurogenic intermittent claudication. Conservative and surgical management of lumbar spinal stenosis has been shown to be minimally effective on its symptoms. A treatment option that has not been investigated in the United States is the utilization of prostaglandin E1 analogs, which have been used primarily in Japan for the treatment of lumbar spinal stenosis since the 1980s. The vasodilatory and antiplatelet aggregation effects of prostaglandin E1 presumably improve symptoms of lumbar spinal stenosis by increasing blood flow to the spinal nerve roots. This brief report examines the potential vascular pathology of lumbar spinal stenosis, reviews evidence on the use of prostaglandin E1 analog limaprost in Japan for lumbar spinal stenosis, and briefly discusses misoprostol as a possible alternative in the United States. The studies summarized in this report suggest that prostaglandin E1 analogs may provide benefit as a conservative treatment option for patients with lumbar spinal stenosis. However, higher-quality studies conducted in the United States and comparison with other currently used conservative treatments are required before it can be recommended for routine clinical use.

An analysis of predictors for heavy alcohol drinking using nationally representative survey data in Japan

Background

Predictors of heavy or moderate alcohol drinking behavior have not been investigated using recent nationally representative survey data in Japan. This study investigated the effects of the predictors of heavy and moderate alcohol drinking in Japan using nationally representative survey data.

Methods

Anonymous data from the 2013 Comprehensive Survey of Living Conditions in Japan were used to compare the predictors of heavy and moderate drinkers with those who abstain. Anonymized data that are resampled from all the survey data from the Ministry of Health, Labour and Welfare were obtained. Age group, marital status, living arrangements, educational level, household income, smoking status, and employment type were used as the explanatory variables. In addition, the drinking status (i.e., heavy drinker, moderate drinker, or abstainer) was used as the outcome variable. A multinomial logistic regression model was used, and an analysis comparing heavy drinkers and abstainers, as well as moderate drinkers and abstainers, was conducted.

Results

Moderate drinking was positively associated with high educational level or high household income for men and women, as well as married status for men. In addition, unemployment was found to be negatively associated with heavy drinking for men and women, and an unmarried status was also found to be negatively associated with heavy drinking for men. Moreover, lower educational levels and smoking prevalence were found to be associated with heavy drinking for men and women. Furthermore, living alone for men and working in a large-scale company for women were also found to be predictors of heavy drinking.

Conclusions

The preventive measures for heavy drinking were suggested to be particularly needed for those with lower educational levels and smokers. A call for attention among men living alone and among female employees in large-scale workplaces is also needed.

Cross-classified multilevel models (CCMM) in health research: A systematic review of published empirical studies and recommendations for best practices

Recognizing that health outcomes are influenced by and occur within multiple social and physical contexts, researchers have used multilevel modeling techniques for decades to analyze hierarchical or nested data. Cross-Classified Multilevel Models (CCMM) are a statistical technique proposed in the 1990s that extend standard multilevel modeling and enable the simultaneous analysis of non-nested multilevel data. Though use of CCMM in empirical health studies has become increasingly popular, there has not yet been a review summarizing how CCMM are used in the health literature. To address this gap, we performed a scoping review of empirical health studies using CCMM to: (a) evaluate the extent to which this statistical approach has been adopted; (b) assess the rationale and procedures for using CCMM; and (c) provide concrete recommendations for the future use of CCMM. We identified 118 CCMM papers published in English-language literature between 1994 and 2018. Our results reveal a steady growth in empirical health studies using CCMM to address a wide variety of health outcomes in clustered non-hierarchical data. Health researchers use CCMM primarily for five reasons: (1) to statistically account for non-independence in clustered data structures; out of substantive interest in the variance explained by (2) concurrent contexts, (3) contexts over time, and (4) age-period-cohort effects; and (5) to apply CCMM alongside other techniques within a joint model. We conclude by proposing a set of recommendations for use of CCMM with the aim of improved clarity and standardization of reporting in future research using this statistical approach.

[Markers of inequality in self-rated health in Brazilian adults according to sex]

The aim of this study was to analyze self-rated health in Brazil's adult population according to markers of health inequality (color or race, region of residence, schooling, per capita household income, and social class), stratified by sex. We studied 59,758 individuals 18 years or older who participated in the 2013 National Health Survey, a population-based household survey. Data collection used face-to-face interviews and key physical measurements. Self-rated health was classified as positive, fair, or negative. Multinomial logistic regression was used to estimate crude and adjusted odds ratios (OR) and respective 95% confidence intervals (95%CI). Percentage agreement and kappa values were calculated to compare the results obtained by regression models and the expected values. Prevalence of positive self-rated health in the overall population was 66.2% (70% in men and 62.6% in women). In the adjusted analysis, the odds of worse self-rated health were significantly higher in individuals with lower per capita household income, less schooling, from the lowest social classes, residents of the North and Northeast regions, and those with brown and black color/race. Public policies for health promotion and recovery in these more vulnerable social groups can help reduce the persistent health inequalities in Brazil.

36-year trends in educational inequalities in self-rated health among Finnish adults

Health inequalities exist across countries and populations, but little is known about their long-term trends and even less about factors shaping the trends. We examined the magnitude of absolute and relative educational inequalities in self-rated health over 36 years among Finnish adults, considering individual covariates and macro-economic fluctuations. Our data were derived from representative annual cross-sectional surveys in 1979-2014 conducted among adult men and women. Participants aged 25-64 were included and nine periods used (n = 8870-14235). Our health outcome was less-than-good self-rated health (SRH) and our socioeconomic indicator was completed years of education as a continuous variable. Educational inequalities in self-rated health were analysed using the relative index of inequality (RII) and the slope index of inequality (SII). Nine time-variant sociodemographic and health-related covariates were included in the analyses. Linear trends suggested stable or slightly curvilinear overall trends in both absolute and relative health equalities over 36 years. Among men, absolute and relative inequalities narrowed immediately after economic recession in Finland in 1993-1994. Among women, inequalities narrowed during financial crisis in 2008-2009. Adjusting for most covariates reduced the magnitude of inequalities throughout the nine periods, but affected little the temporal patterning of health inequalities. Educational inequalities in self-rated health remained during 36 years in Finland. While among men and women health inequalities narrowed during and after recessions, they widened soon back to the pre-recession level. The perseverance of the trends calls for novel and powerful measures to tackle health inequalities.

Health, psychological, social and environmental mediators between socio-economic inequalities and participation in exercise among elderly Japanese

This study examined which of the identified health, psychological, social and environmental mediators could most effectively explain the socio-economic status (SES)-based differences in participation in exercise among elderly Japanese. The candidates for mediators were composed based on the socio-ecological model. A representative sample of people 65 years and older living in two areas with different residential SES in Tokyo, Japan produced 739 effective participants. The intensity of exercise was evaluated based on whether the participants exercise for 30 minutes or longer twice a week, or for 20 minutes or longer three times a week. SES was evaluated by education and income. Mediators were assessed through four dimensions: (a) health, (b) psychological status, (c) social relations and (d) environmental context. As a result, SES's indirect effect through the mediators was evaluated using a multiple mediator model. The influence of both education and income on exercise was mediated by self-efficacy for exercise and social support for exercise. Self-efficacy for exercise had the strongest effect, while social support for exercise explained more of the income differences affecting participation in exercise than it did regarding educational differences. Self-efficacy for exercise may have the strongest effect as a mediator, which would explain the differences in participation in exercise among elderly Japanese based on education and income.

Relationships among Socioeconomic Factors and Self-rated Health in Japanese Adults: NIPPON DATA2010

BACKGROUND

The distributions of socioeconomic status (SES) factors have been changing in Japan. We examined the relationships among SES and self-rated health (SRH) in Japanese adults.

METHODS

We analyzed 1,178 men and 1,555 women. We showed the distribution of SRH by sex and age and examined cross-sectional relationships among educational attainment, marital/living statuses, working status, household income and expenditure, and fine SRH (defined as excellent, very good, or good). We adjusted for age, subjective symptoms, visiting doctors, monthly equivalent household expenditure (EHE), and living in their own house.

RESULTS

The age-standardized prevalence of fine SRH was 79% and 73% among men and women, respectively. Among men, graduating from high school (adjusted odds ratio [aOR] 1.53; 95% confidence interval [CI], 1.07-2.19, relative to graduating from elementary or junior high school) and university or junior college (aOR 1.74; 95% CI, 1.15-2.62) was associated with fine SRH. Among women, graduating from university or junior college was associated with fine SRH (aOR 1.65; 95% CI, 1.12-2.46). Neither marital/living status nor working status was associated with SRH after adjustments for age in either sex. Among women, high EHE and income were associated with fine SRH (the highest expenditure group: aOR 1.80; 95% CI, 1.22-2.65; the highest income group: aOR 2.15; 95% CI, 1.34-3.46, relative to the corresponding lowest group). These simple relationships were not observed for men.

CONCLUSIONS

High educational attainment was associated with fine SRH. Relationships among household income, EHE, and fine SRH differed by sex.

Socioeconomic status disparities in late-life disability based on age, period, and cohort in Japan

INTRODUCTION

Effects of disparities in socioeconomic status (SES) on late-life disabilities have been reported around the world. However, there are only a few studies that have examined age, period, and cohort dependent influences of SES disparities on late-life disabilities. We investigated associations between SES disparities and late-life disability based on the Age-Period-Cohort. We also investigated how macro-economic conditions unique to a period, or a cohort might explain the period or the cohort trends.

METHODS

Data were obtained from people aged 65 and over that responded to the Comprehensive Survey of Living Conditions, which had been conducted every three years from 1989 to 2013. SES was assessed via household income. Disability was assessed as disabilities in performing Basic Activities of Daily Living (BADL). Income disparities were evaluated by the slope index of inequality (SII) and the relative index of inequality (RII). Each Age-Period-Cohort dimension was simultaneously controlled using a model for cross-classification of random effects.

RESULTS

Differences in BADL disabilities due to income disparities decreased with age and reversed after approximately 80 years of age. Income disparities in BADL disability changed across periods, by increasing in periods with a high unemployment rate, which started two to four years before the period. Moreover, results of using SII and RII were nearly identical.

CONCLUSIONS

Higher mortality in elderly with lower income might be related to a reduction of income disparities in BADL disability in Japan. Furthermore, exposure to harsh economic conditions might contribute to increased disparities in BADL disability a few years later.