Income differences in mortality: a register-based follow-up study of three million men and women

Low Household Income Increases Hospital Length of Stay and Decreases Home Discharge Rates in Lumbar Fusion

STUDY DESIGN

Retrospective Matched Cohort Study.

OBJECTIVES

Low median household income (MHI) has been correlated with worsened surgical outcomes, but few studies have rigorously controlled for demographic and medical factors at the patient level. This study isolates the relationship between MHI and surgical outcomes in a lumbar fusion cohort using coarsened exact matching.

METHODS

Patients undergoing single-level, posterior lumbar fusion at a single institution were consecutively enrolled and retrospectively analyzed (n = 4263). Zip code was cross-referenced to census data to derive MHI. Univariate regression correlated MHI to outcomes. Patients with low MHI were matched to those with high MHI based on demographic and medical factors. Outcomes evaluated included complications, length of stay, discharge disposition, 30- and 90 day readmissions, emergency department (ED) visits, reoperations, and mortality.

RESULTS

By univariate analysis, MHI was significantly associated with 30- and 90 day readmission, ED visits, reoperation, and non-home discharge, but not mortality. After exact matching (n = 270), low-income patients had higher odds of non-home discharge (OR = 2.5, P = .016) and higher length of stay (mean 100.2 vs 92.6, P = .02). There were no differences in surgical complications, ED visits, readmissions, or reoperations between matched groups.

CONCLUSIONS

Low MHI was significantly associated with adverse short-term outcomes from lumbar fusion. A matched analysis controlling for confounding variables uncovered longer lengths of stay and higher rates of discharge to post-acute care (vs home) in lower MHI patients. Socioeconomic disparities affect health beyond access to care, worsen surgical outcomes, and impose costs on healthcare systems. Targeted interventions must be implemented to mitigate these disparities.

Who benefits from alcohol screening and brief intervention? A mini-review on socioeconomic inequalities with a focus on evidence from the United States

Alcohol-attributable mortality contributes to growing health inequalities. Addressing hazardous alcohol use and alcohol use disorders through alcohol screening and brief intervention is therefore a promising public health strategy to improve health equity. In this narrative mini-review, we discuss the extent to which socioeconomic differences exist in the alcohol screening and brief intervention cascade, highlighting the example of the United States. We have searched PubMed to identify and summarize relevant literature addressing socioeconomic inequalities in (a) accessing and affording healthcare, (b) receiving alcohol screenings, and/or (c) receiving brief interventions, focusing predominantly on literature from the Unites States. We found evidence for income-related inequalities in access to healthcare in the United States, partly due to inadequate health insurance coverage for individuals with low socioeconomic status. Alcohol screening coverage appears to be generally very low, as is the probability of receiving a brief intervention when indicated. However, research suggests that the latter is more likely to be provided to individuals with low socioeconomic status than those with high socioeconomic status. Individuals with low socioeconomic status also tend to benefit more from brief interventions, showing greater reductions in their alcohol use. Once access to and affordability of healthcare is ensured and high coverage of alcohol screening is achieved for all, alcohol screening and brief interventions have the potential to enhance health equity by reducing alcohol consumption and alcohol-related health harms.

Impact of lifestyle and socioeconomic position on use of non-steroidal anti-inflammatory drugs: A population-based cohort study

PURPOSE

Lifestyle and socioeconomic position may confound the link between non-steroidal anti-inflammatory drugs (NSAIDs) and cardiovascular events, if associated with NSAID use. We examined this association.

METHODS

We conducted a cohort study of all adult first-time responders to the Danish National Health Surveys of 2010, 2013, or 2017 without an NSAID prescription within 3 months before survey completion (n = 407 395). Study exposures were weight, smoking status, alcohol consumption, binge drinking frequency, physical activity level, marital status, highest achieved level of education, income, and employment status. We used a Cox model to compute hazard ratios of time to first redemption of an NSAID prescription and a cumulative odds model to compute odds ratios (ORs) of redeeming one additional NSAID prescription in the year after survey completion.

RESULTS

Total follow-up time was 1 931 902 years. The odds of redeeming one additional NSAID prescription in the year after survey completion varied within all categories of lifestyle and socioeconomic position. The largest ORs were observed within categories of weight (1.70, 95% CI: 1.65-1.74 for obesity vs. normal weight), smoking status (1.24, 95% CI: 1.21-1.27 for current vs. never use), and education (1.44, 95% CI: 1.39-1.49 for primary or other vs. university or higher education). The Cox model showed consistent results.

CONCLUSIONS

Markers of unhealthy lifestyle and low socioeconomic position were associated with initiation and prolonged NSAID use. Consideration of lifestyle and socioeconomic markers as potential confounders in NSAID studies is therefore recommended.

Associations Between Cognitive Functioning and Mortality in a Population-Based Sample of Older United States Adults: Differences by Sex and Education

Objective: To determine whether cognition is associated with mortality among older US adults. Methods: We studied 5,989 National Health and Nutrition Examination Survey participants age 60+ in years 1999-2014 with mortality follow-up through 2015. Cognitive function was measured in one standard deviation decrements using the Digit Symbol Substitution Test (DSST), Animal Fluency (AnFl), and two Consortium to Establish a Registry for Alzheimer's Disease (CERAD) tests. Results: Each decrement in cognitive function was associated with increased risk of mortality overall (DSST HR: 1.36, 95% CI: 1.25, 1.48), among women only (AnFl: 1.51, 95% CI: 1.02, 2.24), and among those with less than a high school education only (AnFl HR: 1.46, 95% CI: 1.09, 1.97; CERAD-WL HR: 1.34, 95% CI: 1.07, 1.67; and CERAD-DR HR: 1.38, 95% CI: 1.05, 1.82). Discussion: Among US adults, lower cognitive functioning was associated with mortality; associations were stronger among women and those with less education.

Inequality in the Face of Death: The Income Gradient in Mortality of the Spanish Pre-Recession Working-Age Population

The purpose of this paper is to evaluate the association between socioeconomic status (SES) and mortality over a three-year period for working-age Spaniards (2007-2009), paying particular attention to the effect of income level. The analysis is relatively new in Spain, and the studies are limited. Neither income nor wealth are included in existing Spanish mortality studies. The main reason for this limitation is the nature of the data sets used, mainly Census Records. We overcome this problem by using data on 693,994 individuals taken from a Social Security sampling and used to estimate the probabilities of death for each income decile and the mortality rate ratios in three different models: (1) using only income, controlled by age and sex, (2) adding socio-economic and geographical variables, and (3) adding level of education. However, the data used here also have some limitations. They do not include government employees, the military or the Department of Justice personnel, whose exclusion we believe causes an under-representation of highly educated people in our sample. The results confirm that there is a non-linear relationship between mortality and income. This non-linear relationship implies that income redistribution resulting from progressive taxation systems could lead to higher reductions in mortality for low-income groups than the reductions induced in the mortality of the high-income population, thus reducing overall mortality.

The impact of income definitions on mortality inequalities

Income is a strong predictor of adult mortality. Measuring income is not as simple as it may sound. It can be conceptualized at the individual or the household level, with the former better reflecting an individual's earning ability, and the latter better capturing living standards. Furthermore, respondents are often grouped into income categories based on their positions in the income distribution, and this operationalization can be done on the basis of age-specific or total population income distributions. In this study, we look at how four combinations of different conceptualizations (individual vs. household) and operationalizations (age-specific vs. total population) of income can affect mortality inequality estimates. Using Finnish registry data, we constructed period life tables for ages 25+ from 1996 to 2017 by gender and for four income definitions. The results indicated that the slope index of inequality for life expectancy varied by 1.1-5.7 years between income definitions, with larger differences observed for women than for men. The overall age patterns of relative index of inequality for mortality rates yielded by the four definitions were similar, but the levels differed. The period trends across income definitions were consistent for men, but not for women. We conclude that researchers should pay particular attention to the choice of the income definitions when analyzing the association between income and mortality, and when comparing the magnitude of inequality across studies and over time.

The effect of income level on all-cause mortality and suicide among patients using antidepressants: A population-based cohort study

BACKGROUND

To investigate whether household income levels are associated with all-cause mortality and suicide in patients using antidepressant agents.

METHODS

We analyzed data from 75,782 patients using antidepressants, acquired from the Korean National Health Insurance claims database (2002-2013). Each patient was monitored until December 2013 or until death, whichever occurred sooner. Cox proportional hazard models were used to compare all-cause and suicide mortalities between different income groups after adjusting for possible confounding covariates and risk factors.

RESULTS

The mid-low income group had a significantly higher suicide rate than the high-income group (hazard ratio [HR] 1.379; 95% confidence interval [CI] 1.102-1.762). Male patients in the low and mid-low income groups had a higher risk of suicide (HR 1.449; 95% CI, 1.006-2.087 and HR 1.410; 95% CI, 1.036-1.918, respectively), whereas there was no significant difference in suicide risk between income groups among female patients.

CONCLUSION

Promotion of targeted policies and priority health services for low-income patients on antidepressants may help reduce the risk of suicide in this high-risk group.

Does death really make us equal? Educational attainment and resource compensation after paternal death in Finland

Attempts to explain the persistent importance of family background for children's educational attainment typically highlight the ways in which parents pass down educational, economic and social resources to their children. However, parental resources may also play a crucial role for preventing family crises from spiraling into cumulative disadvantage. To study such compensation processes, we examine the consequences of a father's death on children's educational trajectories, using a Finnish register-based sample of children born between 1982 and 1987. The results based on multilevel linear probability models both support and contradict our compensation hypothesis. Children who lost their father were not more likely to drop out of upper secondary school, as long as their surviving mother had high levels of socioeconomic resources. Similar compensation processes were visible in the case of entering polytechnic higher education. However, with regard to university attendance, bereavement noticeably reduced the traditional advantage of children with high-resource parents.

Shape of the association between income and mortality: a cohort study of Denmark, Finland, Norway and Sweden in 1995 and 2003

OBJECTIVES

Prior work has examined the shape of the income-mortality association, but work has not compared gradients between countries. In this study, we focus on changes over time in the shape of income-mortality gradients for 4 Nordic countries during a period of rising income inequality. Context and time differentials in shape imply that the relationship between income and mortality is not fixed.

SETTING

Population-based cohort study of Denmark, Finland, Norway and Sweden.

PARTICIPANTS

We collected data on individuals aged 25 or more in 1995 (n=12.98 million individuals, 0.84 million deaths) and 2003 (n=13.08 million individuals, 0.90 million deaths). We then examined the household size equivalised disposable income at the baseline year in relation to the rate of mortality in the following 5 years.

RESULTS

A steep income gradient in mortality in men and women across all age groups except the oldest old in Denmark, Finland, Norway and Sweden. From the 1990s to 2000s mortality dropped, but generally more so in the upper part of the income distribution than in the lower part. As a consequence, the shape of the income gradient in mortality changed. The shift in the shape of the association was similar in all 4 countries.

CONCLUSIONS

A non-linear gradient exists between income and mortality in most cases and because of a more rapid mortality decline among those with high income the income gradient has become steeper over time.

Measuring the effects of CVD interventions and studies across socioeconomic groups: A brief review

There is a known socioeconomic skew in prevalence and outcomes of cardiovascular disease (CVD). To document the proportion of clinical trials and observational studies related to CVD recently published in peer-reviewed journals that report the socio-economic distributional differences in their outcomes. We undertook a review of peer-reviewed clinical trials and observational studies relating to CVD published between 01/06/2015-31/12/2015 in PubMed; and identified the proportion that included measures of socioeconomic status and the proportion that stratified results by, or controlled for, socioeconomic status when reporting outcomes. 414 peer reviewed publications reporting the outcomes of clinical trials or observational studies that related to CVD were identified. 32 of these reported on the socioeconomic status of participants. Of these, 20 stratified the results by socioeconomic status or adjusted the results for socioeconomic status. 18 studies measured education attainment, 5 measured income, 1 measured rurality and 1 measured occupation. Of the 414 articles reporting the outcomes of clinical trials or observational studies related to cardiovascular disease in 2015, the effectiveness of the intervention, or the differences in outcomes, between socioeconomic groups was assessed in 5% of studies. This lack of consideration of the effectiveness of trial outcomes or the differences in outcomes across socioeconomic groups impairs the ability of readers, healthcare professionals and policy makers to assess the impact of new treatments or interventions in closing the inequality gap associated with CVD.

Socioeconomic differences in suicide mortality by sex in Finland in 1971—2000: A register-based study of trends, levels, and life expectancy differences

Aim: Suicide is a common cause of death in many Western countries and it has been predicted to become even more common worldwide. The authors analysed socioeconomic differences and trends in Finnish suicide mortality, and assessed the relevance to public health by calculating socioeconomic differences in years of life expectancy lost attributable to suicide. Data and methods: Census records were used, linked with the death records of men and women aged 25 years and over in 1971—2000 in Finland. Results: Suicide among male and female manual workers was 2.3 and 1.3 times higher respectively than among upper non-manual workers. The differences were largest among those in their thirties. Because of the decline in suicide among upper non-manual workers and a slower decrease or even an increase among other socioeconomic groups, the relative mortality differences increased somewhat during 1970—90, then decreased in the 1990s but remained higher than in the 1970s. In 1991—2000 the suicide-related life expectancy gap between the upper non-manual and manual male workers was 0.6 years, and this difference contributed 10% to the total difference in years of life expectancy lost between these socioeconomic groups. Conclusion: Large and persistent socioeconomic differences were found in suicide mortality and suicide was an important component of the socioeconomic difference in total mortality. Reducing these differences could significantly improve equity in health and reduce the burden of excess mortality.

Health inequalities after austerity in Greece

Since the beginning of economic crisis, Greece has been experiencing unprecedented levels of unemployment and profound cuts to public budgets. Health and welfare sectors were subject to severe austerity measures, which have endangered provision of as well as access to services, potentially widening health inequality gap. European Union Statistics on Income and Living Conditions data show that the proportion of individuals on low incomes reporting unmet medical need due to cost doubled from 7 % in 2008 to 13.9 % in 2013, while the relative gap in access to care between the richest and poorest population groups increased almost ten-fold. In addition, austerity cuts have affected other vulnerable groups, such as undocumented migrants and injecting drug users. Steps have been taken in attempt to mitigate the impact of the austerity, however addressing the growing health inequality gap will require persistent effort of the country’s leadership for years to come.

Effects of Individual, Spousal, and Offspring Socioeconomic Status on Mortality Among Elderly People in China

BACKGROUND

The relationship between socio-economic status and health among elderly people has been well studied, but less is known about how spousal or offspring's education affects mortality, especially in non-Western countries. We investigated these associations using a large sample of Chinese elderly.

METHODS

The data came from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from the years 2005 to 2011 (n = 15 355, aged 65-105 years at baseline; 5046 died in 2008, and 2224 died in 2011). Educational attainment, occupational status, and household income per capita were used as indicators of socio-economic status. Spousal and offspring's education were added into the final models. The Cox proportional hazards model was used to study mortality risk by gender.

RESULTS

Adjusted for age, highly educated males and females had, on average, 29% and 37% lower mortality risk, respectively, than those with a lower education. Particularly among men, this effect was observed among those whose children had intermediate education only. A higher household income was also associated with lower mortality risk among the elderly. Male elderly living with a well-educated spouse (HR 0.79; 95% CI, 0.64-0.99) had a lower mortality risk than those living with a low-educated spouse.

CONCLUSIONS

Both the socio-economic status of the individual and the educational level of a co-resident spouse or child are associated with mortality risk in elderly people. The socio-economic position of family members plays an important role in producing health inequality among elderly people.

Health inequalities in the Netherlands: trends in quality-adjusted life expectancy (QALE) by educational level

BACKGROUND

Quality-adjusted life expectancy (QALE) has been proposed as a summary measure of population health because it encompasses multiple health domains as well as length of life. However, trends in QALE by education or other socio-economic measure have not yet been reported. This study investigates changes in QALE stratified by educational level for the Dutch population in the period 2001-2011.

METHODS

Using data from multiple sources, we estimated mortality rates and health-related quality of life (HRQoL) as functions of age, gender, calendar year and educational level. Subsequently, predictions from these regressions were combined for calculating QALE at ages 25 and 65. QALE changes were decomposed into effects of mortality and HRQoL.

RESULTS

In 2001-2011, QALE increased for men and women at all educational levels, the largest increases being for highly educated resulting in a widening gap by education. In 2001, at age 25, the absolute QALE difference between the low and the highly educated was 7.4 healthy years (36.7 vs. 44.1) for men and 6.3 healthy years (39.5 vs. 45.8) for women. By 2011, the QALE difference increased to 8.1 healthy years (38.8 vs. 46.9) for men and to 7.1 healthy years (41.3 vs. 48.4) for women. Similar results were observed at age 65. Although the gap was largely attributable to widening inequalities in mortality, widening inequalities in HRQoL were also substantial.

CONCLUSIONS

In the Netherlands, population health as measured by QALE has improved, but QALE inequalities have widened more than inequalities in life expectancy alone.

The Association of Socioeconomic Status With Subclinical Myocardial Damage, Incident Cardiovascular Events, and Mortality in the ARIC Study

The association between socioeconomic status (SES) and subclinical cardiovascular disease is not well understood. Using data from the Atherosclerosis Risk in Communities Study, we sought to evaluate the cross-sectional and prospective associations of SES, measured by annual income and educational level, with elevated high-sensitivity cardiac troponin T (hs-cTnT) concentrations (≥14 ng/L) using Poisson and multinomial logistic regressions, respectively. We used Cox proportional hazard models to compare the risks of coronary heart disease, heart failure, and mortality according to SES, stratified by baseline hs-cTnT concentration. Our study baseline was 1990-1992, with follow-up through 2011. We found an independent association between SES and hs-cTnT. When comparing participants in the lowest educational level group to those in the highest, the adjusted prevalence ratios for elevated hs-cTnT were 1.36 (95% confidence interval: 1.05, 1.75) overall, 1.83 (95% confidence interval: 1.23, 2.71) in blacks, and 1.05 (95% confidence interval: 0.73, 1.52) in whites (P for interaction = 0.08). Among participants with nonelevated hs-cTnT concentrations, when comparing those in the lowest income groups to those in the highest, the adjusted hazard ratios were strongest for heart failure and death. Having elevated baseline hs-cTnT doubled the risk of heart failure and death. Persons with low SES and elevated hs-cTnT concentrations have the greatest risk of cardiovascular events, which suggests that this group should be aggressively targeted for cardiovascular risk reduction.

The contribution of education, social class and economic activity to the income-mortality association in alcohol-related and other mortality in Finland in 1988-2012

AIMS

First, to quantify trends in the contribution of alcohol-related mortality to mortality disparity in Finland by income quintiles. Secondly, to estimate the degree to which education, social class and economic activity explain the income-mortality association in alcohol-related and other mortality in four periods within 1988-2012.

DESIGN

Register-based longitudinal study using an 11% random sample of Finnish residents linked to socio-economic and mortality data in 1988-2012 augmented with an 80% sample of all deaths during 1988-2007. Mortality rates and discrete time survival regression models were used to assess the income-mortality association following adjustment for covariates in 6-year periods after baseline years of 1988, 1994, 2001, and 2007.

SETTING

Finland.

PARTICIPANTS

Individuals aged 35-64 years at baselines. For the four study periods for men/women, the final data set comprised, respectively, 26,360/12,825, 22,561/11,423, 20,342/11,319 and 2651/1514 deaths attributable to other causes and 7517/1217, 8199/1450, 9807/2116, 1431/318 deaths attributable to alcohol-related causes.

MEASUREMENTS

Alcohol-related deaths were analysed with household income, education, social class and economic activity as covariates.

FINDINGS

The income disparity in mortality originated increasingly from alcohol-related causes of death, in the lowest quintile the contribution increasing from 28 to 49% among men and from 11 to 28% among women between periods 1988-93 and 2007-12. Among men, socio-economic characteristics attenuated the excess mortality during each study period in the lowest income quintile by 51-62% in alcohol-related and other causes. Among women, in the lowest quintile the attenuation was 47-76% in other causes, but there was a decreasing tendency in the proportion explained by the covariates in alcohol-related mortality.

CONCLUSIONS

The income disparity in mortality among working-age Finns originates increasingly from alcohol-related causes of death. Roughly half the excess mortality in the lowest income quintile during 2007-12 is explained by the covariates of household income, education, social class and economic activity.

A Global Perspective on Cardiovascular Disease in Vulnerable Populations

Cardiovascular disease (CVD) is a major contributor to the growing public health epidemic in chronic diseases. Much of the disease and disability burden from CVDs are in people younger than the age of 70 years in low- and middle-income countries, formerly "the developing world." The risk of CVD is heavily influenced by environmental conditions and lifestyle variables. In this article we review the scope of the CVD problem in low- and middle-income countries, including economic factors, risk factors, at-risk groups, and explanatory frameworks that hypothesize the multifactorial drivers. Finally, we discuss current and potential interventions to reduce the burden of CVD in vulnerable populations including research needed to evaluate and implement promising solutions for those most at risk.

Women's relative immunity to the socio-economic health gradient: artifact or real?

Background

Individual and area socio-economic status (SES) are significant predictors of morbidity and mortality in developed and developing countries. However, the span in health from poorest to richest, that is, the socio-economic gradient, appears steeper for men than women.

Objective

Our aim is to understand women's apparent immunity to the health harms of the SES gradient.

Design

Findings from a non-systematic search of Medline for population-based, SES gradient studies reporting results for both men and women and with health outcomes of morbidity, mortality or self-rated health (SRH) were reflectively analyzed.

Results

The 36 papers reviewed generally showed women to be relatively immune to the SES gradient for all but cardiovascular health outcomes. However, addressing the interconnected nature of socio-economic circumstances, exploring whether some measures of SES had ambiguous meanings for either women or men, including modifiers of SES such as household circumstances, social capital or area gender equity, or using indicators of area SES that were contextual rather than aggregates of individual, compositional measures increased the SES gradient for women. Outcome measures that combined mental and physical health, accounted for gender differences in SRH and adjusted for sex-specific differences in causes of mortality also explained some of the observed amelioration of the SES gradient among women.

Conclusions

Socio-economic circumstances have a real and sustained impact on individual health. The SES gradient appears stronger for men than for women for all health outcomes other than heart disease. However, some of the observed variability between men and women may be an artifact of biased methodology. Considering webs of causation rather than individual markers of SES along with other sources of gender bias can explain much of women's blunted socio-economic gradient and deepen understanding of the pathways from SES to morbidity and mortality overall.

Evaluating access to primary health care among older women and men in Barbados using preventable hospitalization

We evaluated access to primary health care for older women and men in Barbados, a developing country, using a widely accepted access indicator, hospitalization for ambulatory care sensitive conditions. Using 2003-2008 data, we calculated gender-specific total annual population-based rates of these hospitalizations per 1,000 older women and men and individual rates for the six most prevalent conditions. Across the 6 years, these hospitalizations increased 33.6% for women, 30.6% for men (both P < .0001). However, the average rate for diabetes fell 32% for women, 36% for men. Findings suggest an opportunity to improve access to primary health care, particularly for older women.

Childhood family background and mortality differences by income in adulthood: fixed-effects analysis of Finnish siblings

BACKGROUND

Events and conditions during childhood have been found to affect health and mortality at later stages in life. We studied whether childhood conditions explain the observed all-cause and cause-specific mortality disparity between income groups in adulthood.

METHODS

We used a 10% register linked sample of Finnish households in the 1950 census identifying 51 647 children aged 0-14 with at least one sibling of the same sex and followed them for mortality from the age 35 until ages 57-72. Using Cox regression with sibling design, we estimated hazard ratios (HRs) for quintiles of personal income at the age 35. We controlled for observed childhood family sociodemographic characteristics and allowed different baseline hazard functions for each group of siblings in order to control for all shared unobserved characteristics within families.

RESULTS

Accounting for the observed childhood characteristics did not attenuate the income disparity in mortality, whereas adjusting for the sociodemographic characteristics in adulthood reduced the difference of the lowest quintiles by ∼70% among men and 30-40% among women. Controlling for the unobserved childhood characteristics in the sibling design did not provide any further explanation to the income differentials in mortality. This applied also for cause-specific mortality among men. HR to the cardiovascular diseases was 38% higher and 73% higher in alcohol, accidental and violent causes in the lowest quintile even after adjusting for all observed and unobserved characteristics.

CONCLUSIONS

The excess mortality in the lowest income quintiles persists even after shared childhood family conditions among siblings are accounted for.

Socioeconomic differences in selected dietary habits among Norwegian 13-14 year-olds: a cross-sectional study

BACKGROUND

Social inequalities in health are a major and even growing problem in all European countries.

OBJECTIVE

The aim of the present study was to describe 1) differences in dietary habits among Norwegian adolescents by gender and socioeconomic status; 2) differences in self-reported knowledge of dietary guidelines among their parents according to socioeconomic status.

DESIGN

In 2012, a cross-sectional study where students filled in a web-based food frequency questionnaire at school was conducted in nine lower secondary schools in Vest-Agder County, Norway. Socioeconomic status (SES) and knowledge of dietary guidelines were obtained from the parents using a web-based questionnaire. In total, 517 ninth-grade students (mean age 13.9) out of 742 invited students participated in the study, giving a participation rate of 69.7%. The total number of dyads with information on both parents and students was 308 (41.5%).

RESULTS

The findings indicate that there is a tendency for girls to have a healthier diet than boys, with greater intake of fruits and vegetables (girls intake in median 3.5 units per day and boys 2.9 units per day), and lower intake of soft drinks (girls 0.25 l in median versus boys 0.5 l per week). Students from families with higher SES reported a significant higher intake of vegetables and fish, and lower intake of soft drinks and fast food than those from lower SES. Parents with higher SES reported a significantly better knowledge of dietary guidelines compared to those with lower SES.

CONCLUSIONS

Differences in dietary habits were found between groups of students by gender and SES. Differences were also found in parents' self-reported knowledge of dietary guidelines. This social patterning should be recognized in public health interventions.

All part of the job? The contribution of the psychosocial and physical work environment to health inequalities in Europe and the European health divide

This study is the first to examine the contribution of both psychosocial and physical risk factors to occupational inequalities in self-assessed health in Europe. Data from 27 countries were obtained from the 2010 European Working Conditions Survey for men and women aged 16 to 60 (n = 21,803). Multilevel logistic regression analyses (random intercept) were applied, estimating odds ratios of reporting less than good health. Analyses indicate that physical working conditions account for a substantial proportion of occupational inequalities in health in both Central/Eastern and Western Europe. Physical, rather than psychosocial, working conditions seem to have the largest effect on self-assessed health in manual classes. For example, controlling for physical working conditions reduced the inequalities in the prevalence of"less than good health" between the lowest (semi- and unskilled manual workers) and highest (higher controllers) occupational groups in Europe by almost 50 percent (Odds Ratio 1.87, 95% Confidence Interval 1.62-2.16 to 1.42, 1.23-1.65). Physical working conditions contribute substantially to health inequalities across "post-industrial" Europe, with women in manual occupations being particularly vulnerable, especially those living in Central/Eastern Europe. An increased political and academic focus on physical working conditions is needed to explain and potentially reduce occupational inequalities in health.

Socioeconomic differences in alcohol-attributable mortality compared with all-cause mortality: a systematic review and meta-analysis

BACKGROUND

Factors underlying socioeconomic inequalities in mortality are not well understood. This study contributes to our understanding of potential pathways to result in socioeconomic inequalities, by examining alcohol consumption as one potential explanation via comparing socioeconomic inequalities in alcohol-attributable mortality and all-cause mortality.

METHODS

Web of Science, MEDLINE, PsycINFO and ETOH were searched systematically from their inception to second week of February 2013 for articles reporting alcohol-attributable mortality by socioeconomic status, operationalized by using information on education, occupation, employment status or income. The sex-specific ratios of relative risks (RRRs) of alcohol-attributable mortality to all-cause mortality were pooled for different operationalizations of socioeconomic status using inverse-variance weighted random effects models. These RRRs were then combined to a single estimate.

RESULTS

We identified 15 unique papers suitable for a meta-analysis; capturing about 133 million people, 3 741 334 deaths from all causes and 167 652 alcohol-attributable deaths. The overall RRRs amounted to RRR = 1.78 (95% confidence interval (CI) 1.43 to 2.22) and RRR = 1.66 (95% CI 1.20 to 2.31), for women and men, respectively. In other words: lower socioeconomic status leads to 1.5-2-fold higher mortality for alcohol-attributable causes compared with all causes.

CONCLUSIONS

Alcohol was identified as a factor underlying higher mortality risks in more disadvantaged populations. All alcohol-attributable mortality is in principle avoidable, and future alcohol policies must take into consideration any differential effect on socioeconomic groups.

A matter of perception: exploring the role of income satisfaction in the income-mortality relationship in German survey data 1995-2010

Individual- and community-level income has been shown to be linked to social inequalities in health and mortality. On the individual level, social comparisons and relative deprivation resulting from them have been identified as relevant mechanisms involved in the relationship between income and health, but it is mainly income-based measures of relative deprivation that have been considered in previous studies. Using income satisfaction, this study employs a perception-based indicator of relative deprivation. The study, covering the period between 1995 and 2010, utilized the German Socio-Economic Panel. The follow-up included 11,056 men and 11,512 women at employment age 25-64. Discrete-time survival analysis with Cox regression was performed to estimate the effects of relative income position and income satisfaction on all-cause mortality. The univariate analysis revealed an income gradient on mortality and further showed a strong association between income satisfaction and survival. After education and employment status were adjusted for, the effect of discontent with income on mortality was still present in the female sample, whereas in the male sample only the income gradient prevailed. When self-rated health was controlled for, the hazard ratios of income satisfaction attenuated and turned non-significant for both men and women while the effects of income position remained stable. In conclusion, the findings suggest that income satisfaction and income position measure different aspects of income inequality and complement one another. Income satisfaction appeared to be a possible contributing component to the causal pathway between income and mortality.

Have regional inequalities in life expectancy widened within the European Union between 1991 and 2008?

BACKGROUND

Health inequalities have widened within and between many European countries over recent decades, but Europe-wide sub-national trends have been largely overlooked. For regions across the European Union (EU), we assess how geographical inequalities (i.e., between regions) and sociospatial inequalities (i.e., between regions grouped by an area-level measure of average household income) in male and female life expectancy have changed between 1991 and 2008.

METHODS

Household income, life expectancy at birth and population count data were obtained for 129 regions (level 2 Nomenclature of Statistical Territorial Units, 'NUTS') in 13 European countries with 1991-2008 data (2008 population = 272 million). We assessed temporal changes in the range of life expectancies, for all regions and for Western and Eastern European regions separately.

RESULTS

Between 1991 and 2008, the geographical range of life expectancies found among European regions remained relatively constant, with the exception of life expectancy among male Eastern Europeans, for whom the range widened by 2.8 years. Sociospatial inequalities in life expectancy (1999-2008 data only) remained constant for all regions combined and for Western Europe, but more than doubled in size for male Eastern Europeans. For female Eastern Europeans, life expectancy was unrelated to regional household income.

CONCLUSIONS

Regional life-expectancy inequalities in the EU have not narrowed over 2 decades, despite efforts to reduce them. Household income differences across European regions may partly explain these inequalities. As inequalities transcend national borders, reduction efforts may require EU-wide coordination in addition to national efforts.

Socio-economic inequalities in mortality persist into old age in New Zealand: study of all 65 years plus, 2001–04

A number of studies have explored the relationship between socio-economic status and mortality, although these have mostly been based on the working-age population, despite the fact that the burden of mortality is highest in older people. Using Poisson regression on linked New Zealand census and mortality data (2001–04, 1.3 million person years) with a comprehensive set of socio-economic indicators (education, income, car access, housing tenure, neighourhood deprivation), we examined the association of socio-economic characteristics and older adult mortality (65+ years) in New Zealand. We found that socio-economic mortality gradients persist into old age. Substantial relative risks of mortality were observed for all socio-economic factors, except housing tenure. Most relative risk associations decreased in strength with ageing [e.g. most deprived compared to least deprived rate ratio for males reducing from 1.40 (95% confidence interval (CI) 1.28–1.53) for 65–74-year-olds to 1.13 (CI 1.00–1.28) for 85 + -year-olds], except for income and education among women where the rate ratios changed little with increasing age. This suggests individual-level measures of socio-economic status are more closely related to mortality in older women than older men. Comparing across genders, the only statistically significantly different association between men and women was for a weaker association for women for car access.

A Multiple-Process Latent Transition Model of Poverty and Health

Health researchers often use the life-course perspective, exploring how long-range experiences in one life domain may influence, and be influenced by, those in another. We develop a multiple-process latent transition model (MPLTM) to estimate changes in health and poverty dynamics simultaneously, using repeated measures of self-rated health and income for working-aged adults from the British Household Panel Survey. We apply the model to quantify concurrent and longitudinal effects to assess whether changes in these two processes are related or independent. Model extensions add time-invariant (cohort, gender) and time-varying (weeks nonemployed in previous year) covariates. We find both concurrent and bidirectional longitudinal relationships between poverty and health, with nonemployment appearing to mediate longitudinal health-to-poverty effects and confound longitudinal poverty-to-health effects. The MPLTM can provide quantitative estimates of complex interlocking processes that are often difficult to measure and assess.

Selection and mortality: a ten-year follow-up of income decile mortality in Norway

BACKGROUND

There is universal agreement that higher mortality goes with lower income. Opinions differ on causality: the association may reflect the damaging effect of poverty on health and survival chances. Conversely, it may reflect selection/reverse causation: low income indicates health problems, and from health problems follow a higher risk of dying.

METHODS

We studied all deaths in Norway (111,504) during the 10-year period 1994-2003 among persons aged 25-66 years in 1993 (2,261,076). For each year, age-standardized mortality rates were calculated for each 1993 income decile for men and women separately. Income was calculated as family size-adjusted income after taxes but including cash welfare transfers. If the selection theory was correct, one would expect to see the excess mortality in the lower income fractiles decline as the bad risks, over-represented among the poorer, died away.

RESULTS

Large income decile variations in mortality remained at the end of the 10-year period: after 10 years, the age-standardized mortality rate for men and women was still much higher in the lower income deciles.

CONCLUSION

As the excess mortality in the poorer income deciles was not much reduced during the 10-year period, excess mortality among persons in bad health in the lower income deciles does not explain the income inequality in mortality in our data set.

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.

The Association Between Individual Income and Remaining Life Expectancy at the Age of 65 in the Netherlands

This article quantifies the association between individual income and remaining life expectancy at the statutory retirement age (65) in the Netherlands. For this purpose, we estimate a mortality risk model using a large administrative data set that covers the 1996–2007 period. Besides age and marital status, the model includes as covariates individual and spouse’s income as well as a random individual specific effect. It thus allows for dynamic selection based on both observed and unobserved characteristics. We find that conditional on marital status, individual income is about equally strong and negatively associated with mortality risk for men and women and that spouse’s income is only weakly associated with mortality risk for women. For both men and women, we quantify remaining life expectancy at age 65 for low-income individuals as approximately 2.5 years less than that for high-income individuals.

Intergenerational financial transfers and health in a national sample from France

Financial transfers from parents to their adult children are a growing trend in contemporary societies, and this study investigates the relation of those transfers to their beneficiaries' health in France. In the 2005 nationally representative Gender and Generation Survey, nearly 6% of the subjects aged 25-49 years reported having received financial transfers during the last 12 months. Subjects who had achieved intergenerational upward mobility as well as those who had remained in the upper class were more likely to receive transfers, suggesting that parents rewarded those of their children who achieved most social success. After adjusting for a wide range of socio-demographic factors, subjects who had been given large transfers were much more likely to report very good health than subjects who had not been given anything. Findings were interpreted within the framework of sociological research on intergenerational transfers and that of lifecourse epidemiology.

Social economic inequalities and mental health. I. Concepts, theories and interpretations

Summary

Aims – Reconstructing the models used for approaching the inequalities issues in health, idenfiying the most relevant theoretical and conceptual contributions. Method – Literature electronic-search on Medline, Psyclit, Econlit, Social Science Index and SocioSearch using the key-words inequalities, deprivation, poverty, socio-economic status, social class, occupational class, mental health for the period 1965-2002; integrated with manual search. The material was classified according to the conceptual and theoretical interpretative models or to the analyses of the association 'inequalities-health' where health was expressed as mortality, morbidity or services utilisation. Results – Four different interpretative models about the genesis of inequalities were identified. Further theoretical developments overcome the distinction among conceptuals contrapositions selection versus causation, statistic artefactual versus real differences, individual behaviours versus material context. Since the 80's the concept of material deprivation has been enlarged to include social deprivation to explain health inequalities. The social exclusion is related to material deprivation and to social fragility enlarging the traditional aspects of poverty. The theories that better adapt to the psychiatric field are the social selection and social causation. Conclusions – The social exclusion and the new methodologies for measuring the inequalities seems to be an effective way for understanding of the inexplored aspects of the mental health inequalities.

Declaration of Interest: This work was partly funded by the Department of the Public Health Sciences “G. Sanarelli” of the University of Rome “La Sapienza” and the Department of Medicine and Public Health of the University of Verona.

Income differences in stroke mortality: a 12-year follow-up study of the Swedish working population

AIMS

This study explored the association between income and stroke mortality in the total working population in Sweden and examined whether the associations differ by gender or for stroke subtypes intracerebral haemorrhage (ICH) or brain infarction (BI).

METHODS

This was a register-based study among nearly 3 million working women and men (30-64 years in 1990) with a 12-year follow up (1991-2002) for mortality from stroke (4886 deaths). Income was measured as annual registered income from work in 1990. Gender-specific Cox regressions were applied with adjustments for sociodemographic covariates.

RESULTS

The age-adjusted hazard ratio (95% confidence interval) of lowest versus highest income quartile was 1.80 (1.48-2.19) for any stroke, 1.68 (1.29-2.17) for ICH and 2.23 (1.53-3.22) for BI in women, and the corresponding figures for men were 2.12 (1.92-2.34), 2.02 (1.77-2.31), and 2.09 (1.77-2.46). Adjustment for covariates attenuated these associations to 1.69 (1.33-2.15) for any stroke and 1.56 (1.14-2.14) for ICH in women and to 1.98 (1.74-2.24) for any stroke and 1.77 (1.44-2.19) for BI in men. In contrast, adjustment for covariates amplified the estimates to 2.36 (1.52-3.66) for BI in women and to 2.05 (1.73-2.44) for ICH in men.

CONCLUSIONS

Risk of stroke mortality was highest in the lowest income group, with a gradient for the intermediate groups, in both women and men. The risk of mortality from BI was highest in women with the lowest income and the risk of ICH was highest in men with the lowest income.

Deeper and wider: income and mortality in the USA over three decades

BACKGROUND

Literature on the socio-economic 'gradient' in health often asserts that income is associated with better health not only for the very poor, but also across the entire income distribution. In addition, changes in the shape of the association between incomes during a period of increasing economic inequality have not been previously studied. The goal of the current study was to estimate and compare the shape of the relationship between income and mortality in the USA for the 1970s, the 1980s and the 1990s.

METHODS

Using income and mortality data from the Panel Study of Income Dynamics for respondents aged 35-64 years, we used a Bayesian Cox Model with regression splines to model the risk of mortality over three 10-year follow-up periods. To identify whether income was more strongly associated with mortality at different parts of the income distribution, we treated income as a linear spline with an unknown knot location.

RESULTS

The shape of the association between income and mortality was quite non-linear, with a much stronger association at lower levels of income. The relationship between income and mortality in the USA was also not invariant across time, with the increased risk of death associated with lower income applying to an increasing proportion of the US population over time (9th percentile of income in 1970-79, 20th percentile in 1980-89 and 32nd percentile in 1990-99).

CONCLUSIONS

Our analyses do not support the claim that income is associated with mortality throughout the income distribution, nor is the association between income and mortality the same across periods. Based on our analyses, a focus on the bottom 30% of the income distribution would seem to return the greatest benefits in reducing socio-economic inequalities in health.

Contribution of mortality and disability to the secular trend in health inequality at the turn of century in Belgium

BACKGROUND

There is evidence that health inequalities by socio-economic status have persisted. We examined whether educational differences in Disability-Free Life Expectancy (DFLE) and Disability Life Expectancy (DLE) at age 25 has narrowed or widened between the 1990s and 2000s in Belgium. The contribution of mortality and disability prevalence to the secular trend is investigated.

METHODS

We used disability data from the 1997 and 2004 Belgian Health Interviews Surveys and mortality data from the 3-years follow-up of the 1991 and 2001 census population to assess education-related disparities in DFLE and DLE and to partition these differences into additive contributions of mortality and disability.

RESULTS

Compared to the highest educated population, differences in the prevalence of disability accounted for at least 66% of the inequality in DFLE. In the latest period, the differences in DFLE compared to men with tertiary education was 4.8, 6.6, 9.7 and 18.6 years for men with, respectively higher secondary, lower secondary, primary and no education. Among females, inequalities in DFLE were, respectively 5.8, 5.1, 10.8 and 18.2 years. There was no evidence that the educational differences in DFLE narrowed since the 1990s. Compared to people with the highest educational attainment, the inequalities in DFLE increased over time for all educational groups except for men with primary education.

CONCLUSION

The social divide in health increased over time: people with the highest education continued to live even longer, they continued to live even longer without disability and to live less years with disability.

Income-related health inequalities in the Nordic countries: examining the role of education, occupational class, and age

Numerous studies have concluded that people's socioeconomic position is related to mortality and morbidity, but that the strength of this association varies considerably both within and between European regions. This has spurred several researchers to more closely examine educational and occupational gradients in health in the Nordic countries to clarify the causes of cross-national differences. However, comparable studies using income as an indicator of socioeconomic position are still lacking. This study uses recent and highly comparable data to fill this gap. The aim of this study is threefold. First, we ask to what extent there is an income gradient in health in the Nordic countries, and to what extent the association differs between these countries. Second and third, we examine whether differences in the attenuation of the income gradient by education and occupational class, and age-specific differences between countries, may act as explanations for differences in the income gradient between the Nordic countries. The data source are three waves of the European Social Survey (ESS, 2002/2004/2006), which included 17,801 people aged 25 and over from Denmark, Finland, Norway, and Sweden. Two subjective health measures (physical/mental self reported health and limiting longstanding illness) were analysed by means of logistic regression. The results show that, in all countries, people reported significantly better health and were less likely to suffer from longstanding illness as they had a higher income. This association is strongest in Norway and Finland and weakest in Denmark. The income gradient in health, but not country differences in this gradient, is partly explained by education and occupational class. Additionally, the strength of the income gradient in health varies between age groups. The relatively high health inequalities between income groups in Norway and Finland are already visible in the youngest age groups. The results imply that the socioeconomic gradient in health will arguably not be strongly reduced in the near future as a result of cohort replacement, as has been suggested in previous studies. Health policy interventions may be particularly important five to ten years prior to retirement and in early adulthood.

Inequality in Human Development: An Empirical Assessment of 32 Countries

One of the most frequent critiques of the HDI is that is does not take into account inequality within countries in its three dimensions. In this paper, we apply a simply approach to compute the three components and the overall HDI for quintiles of the income distribution. This allows a comparison of the level in human development of the poor with the level of the non-poor within countries, but also across countries. This is an application of the method presented in Grimm et al. (World Development 36(12):2527-2546, 2008) to a sample of 21 low and middle income countries and 11 industrialized countries. In particular the inclusion of the industrialized countries, which were not included in the previous work, implies to deal with a number of additional challenges, which we outline in this paper. Our results show that inequality in human development within countries is high, both in developed and industrialized countries. In fact, the HDI of the lowest quintiles in industrialized countries is often below the HDI of the richest quintile in many middle income countries. We also find, however, a strong overall negative correlation between the level of human development and inequality in human development.

Socio-Demographic Factors Intensifying Male Mating Competition Exacerbate Male Mortality Rates

Sex differences in mortality rates stem from a complex set of genetic, physiological, psychological, and social causes whose influences and interconnections are best understood in an integrative evolutionary life history framework. Although there are multiple levels of mechanisms contributing to sex based disparities in mortality rates, the intensity of male mating competition in a population may have a crucial role in shaping the level of excess male mortality. The degree of variation and skew in male reproductive success may shape the intensity of male mating competition, leading to riskier behavioral and physiological strategies. This study examines three socio-demographic factors related to variation in human male reproductive success; polygyny, economic inequality, and the population ratio of reproductively viable men to women across nations with available data. The degrees of economic inequality and polygyny explained unique portions in the sex difference in mortality rates, these predictors accounted for 53% of the variance. The population ratio of reproductively viable men to women did not explain any additional variance. These results demonstrate the association between social conditions and health outcomes in modern nations, as well as the power of an evolutionary life history framework for understanding important social issues.

Socioeconomic disparities in health in the United States: what the patterns tell us

OBJECTIVES

We aimed to describe socioeconomic disparities in the United States across multiple health indicators and socioeconomic groups.

METHODS

Using recent national data on 5 child (infant mortality, health status, activity limitation, healthy eating, sedentary adolescents) and 6 adult (life expectancy, health status, activity limitation, heart disease, diabetes, obesity) health indicators, we examined indicator rates across multiple income or education categories, overall and within racial/ethnic groups.

RESULTS

Those with the lowest income and who were least educated were consistently least healthy, but for most indicators, even groups with intermediate income and education levels were less healthy than the wealthiest and most educated. Gradient patterns were seen often among non-Hispanic Blacks and Whites but less consistently among Hispanics.

CONCLUSIONS

Health in the United States is often, though not invariably, patterned strongly along both socioeconomic and racial/ethnic lines, suggesting links between hierarchies of social advantage and health. Worse health among the most socially disadvantaged argues for policies prioritizing those groups, but pervasive gradient patterns also indicate a need to address a wider socioeconomic spectrum-which may help garner political support. Routine health reporting should examine socioeconomic and racial/ethnic disparity patterns, jointly and separately.

Income, education, and inflammation: differential associations in a national probability sample (The MIDUS study)

OBJECTIVE

To examine the associations between income and education and three markers of inflammation: interleukin-6 (IL-6), C-reactive protein (CRP), and fibrinogen. Socioeconomic status is inversely linked with health outcomes, but the biological processes by which social position "gets under the skin" to affect health are poorly understood.

METHOD

Cross-sectional analyses involved participants (n = 704) from the second wave of the national population-based Survey of Midlife Development in the United States (MIDUS). Data on pretax household-adjusted income and educational attainment were collected by questionnaire and telephone interview, respectively. Detailed medical history interviews, inventories of medication, and fasting blood samples for assessment of inflammatory proteins were obtained during an overnight clinic stay.

RESULTS

All three inflammatory proteins were inversely associated with both income and education in bivariate analyses. However, multivariate regression models, adjusting for potential confounds, showed that only low income predicted higher levels of inflammatory proteins. Moreover, inclusion of IL-6 in the regression models for CRP and fibrinogen eliminated the associations with income.

CONCLUSION

These results suggest that income explains the association between education and peripheral inflammation. In short, the reason that higher education is linked to reduced peripheral inflammation is because it reduces the risk for low income status, which is what is directly associated with reduced peripheral inflammation. The findings also suggest that the links between income and both CRP and fibrinogen are mediated by IL-6. These observations help to sharpen our understanding of the relationship between social position and biological markers of illness in the United States.