Commentary: Social capital, social epidemiology and disease aetiology

Vulnerability in health and social capital: a qualitative analysis by levels of marginalization in Mexico

Background

Social capital is employed as an asset when there is a lack of an efficient health-care system. However, this relationship is not homogeneous and can differ according to the characteristics of individuals and their context. In this paper, we aim to analyze the role of social capital in the solution of healthcare problems among individuals with different levels of marginalization and unequal access to health services.

Methods

This qualitative study examines the role of social capital in the demand for healthcare among Mexican individuals with different levels of marginalization. The research draws data from semi-structured interviews (N = 247) that were collected in four Mexican states with different social welfare benefits: Mexico City, Tamaulipas, the State of Mexico, and Oaxaca. The interviewees were selected using the snowball method and other eligibility criteria such as education, age, and gender.

Results

Findings suggest that social capital is a relevant factor in solving healthcare problems, depending on the level of marginalization. The role of social capital can be explained by the precariousness of medical service delivery, the poor health infrastructure, and the difficult access to health care in Mexico. Networks are the main resource to deal with health related issues, food, medicine, and out-of-the-pocket medical expenses in contexts of high levels of marginalization. In the middle level of marginalization, networks also help in raising funds for more-specialized medical services and higher quality hospitals. In the least-marginalized levels, social capital is used as companionship for sick individuals, while support networks act as emotional relief. At this level, most individuals have private health insurance, and many of them have major medical healthcare coverage.

Conclusions

Participants reported low levels of trust in the health care system because of the poor infrastructure and quality of medical service delivery. Although the main criticism is focused on public healthcare institutions, there is a lack of trust in private medical services as well. These facts are related to the access and quality of medical service delivery and turn social capital into a significant asset. Despite that social bonds or links are valuable resources that individuals can use to solve healthcare related issues, the use of social capital is not homogenous. Indeed, it can be influenced by several factors that were represented in this study through the municipal marginalization index.

Rise, stagnation, and rise of Danish women's life expectancy

Health conditions change from year to year, with a general tendency in many countries for improvement. These conditions also change from one birth cohort to another: some generations suffer more adverse events in childhood, smoke more heavily, eat poorer diets, etc., than generations born earlier or later. Because it is difficult to disentangle period effects from cohort effects, demographers, epidemiologists, actuaries, and other population scientists often disagree about cohort effects' relative importance. In particular, some advocate forecasts of life expectancy based on period trends; others favor forecasts that hinge on cohort differences. We use a combination of age decomposition and exchange of survival probabilities between countries to study the remarkable recent history of female life expectancy in Denmark, a saga of rising, stagnating, and now again rising lifespans. The gap between female life expectancy in Denmark vs. Sweden grew to 3.5 y in the period 1975-2000. When we assumed that Danish women born 1915-1945 had the same survival probabilities as Swedish women, the gap remained small and roughly constant. Hence, the lower Danish life expectancy is caused by these cohorts and is not attributable to period effects.

Workplace social capital and risk of long-term sickness absence. Are associations modified by occupational grade?

Background: Workplace social capital (WSC) is an emerging topic among both work environment professionals and researchers. We examined (i) whether high WSC protected against risk of long-term sickness absence (LTSA) in a random sample of the Danish workforce during a 1-year follow-up and (ii) whether the association of WSC with sickness absence was modified by occupational grade. Methods: We measured WSC by self-report in a cohort of 3075 employees and linked responses to a national register of sickness absence. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) of onset of LTSA (≥21 days), adjusted for covariates. We stratified analyses by occupational grade and examined if there was an interaction effect of WSC and occupational grade. Results: A one standard deviation higher WSC score predicted a reduced risk of sickness absence after adjustment for sociodemographic variables, prevalent health problems and health behaviours (HR = 0.85, 95% CI = 0.74–0.99). The HR was attenuated and lost statistical significance after further adjustment for occupational grade (HR = 0.90, 95% CI = 0.78–1.04). When stratified by occupational grade, high WSC predicted a decreased risk of sickness absence among higher grade workers (HR = 0.61, 95% CI = 0.44–0.84) but not among lower grade workers (HR = 0.98, 95% CI = 0.83–1.15). The interaction effect of WSC and occupational grade was statistically significant (HR = 0.97, 95% CI = 0.95–0.99). Conclusion: High WSC might reduce risk of LTSA. However, the protective effect appears to be limited to workers of higher occupational grade.

A study on factors that drive variation in the levels of social capital among people living with HIV/AIDS in Iran

Introduction:

Social capital is increasingly used in relation to health issues, particularly in sexually transmitted diseases/infections and health behaviors. Experiences indicated that social capital can contribute in changing HIV related risk behaviors and a decline of HIV infection through social groups and networking and make more effective use of HIV/AIDS prevention, care, and treatment services. We aimed to assess social capital in these persons through a quantitative study.

Method:

This cross-sectional study was performed with a convenience sample of 300 people living HIV/AIDS referred to a counseling center of behavioral diseases, in Imam Khomeini Hospital, in Tehran, the capital of Iran, during September 2011 to May 2012.

Data collection tools were a demographic questionnaire and World Bank Social Capital Questionnaire (SC-IQ). The analysis of data was performed by the SPSS statistic software version 18. To identify factors influencing social capital in participations, Pearson correlation coefficient, ANOVA, t-test, and a multiple regression were applied. The significant level was considered 0.05 in this study.

Results:

165 (55%) were male and the rest female. The mean age of participants was 34.3±7.5. The mean score of total social capital was 2.34±0.5 in all participants. The domain of individual trust had the highest mean score (2.53±0.66). The lowest mean score was related to the domain of social trust and associative relations (2.23±0.62). Variables such as ethnicity, age, and middle economic status had a significant impact on the domain of individual trust so that the mean score of this component of social capital was lower among women (0.396) than men. Factors affecting total social capital were ethnicity and middle economic status.

Conclusion:

Finding emphasized on the role of economic status, ethnicity and gender in persons living with HIV/AIDS. Thus recommended that policy makers and program managers consider social groups and networks, especially in women in the design and delivery of intervention strategies to reduce HIV transmission.

Trajectories of multimorbidity: exploring patterns of multimorbidity in patients with more than ten chronic health problems in life course

Background

Physicians are frequently confronted with complex health situations of patients, but knowledge of intensive forms of multimorbidity and their development during life is lacking.

This study explores patterns and trajectories of chronic health problems of patients with multimorbidity particularly those with more than ten conditions and type and variety of organ systems involved in these patterns during life.

Method

Life time prevalence patterns of chronic health problems were determined in patients with illness trajectories accumulating more than ten chronic health problems during life as registered by general practitioners in the South of the Netherlands in the Registration Network Family Practices (RNH).

Results

Overall 4,560 subjects (5%) were registered with more than ten chronic health problems during their life (MM11+), accounting for 61,653 (20%) of the 302,808 registered health problems in the population (N = 87,837 subjects). More than 30% accumulates 4 or more chronic health conditions (MM4-5: 4–5 conditions (N = 14,199; 16.2%); MM6-10: 6–10 conditions (N = 14,365; 16.4%).

Gastro-intestinal, cardiovascular, locomotor, respiratory and metabolic conditions occur more frequently in the MM11+ patients than in the other patients, while the nature and variety of body systems involved in lifetime accumulation of chronic health problem clusters is both generic and specific. Regarding chronic conditions afflicting multiple sites throughout the body, the number of neoplasms seems low (N = 3,592; 5.8%), but 2,461 (49%) of the 4,560 subjects have registered at least one neoplasm condition during life. A similar pattern is noted for inflammation (N = 3,537, 78%), infection (N = 2,451, 54%) and injury (N = 3,401, 75%).

Conclusion

There are many challenges facing multimorbidity research, including the implementation of a longitudinal, life-time approach from a family practice perspective. The present study, although exploratory by nature, shows that both general and specific mechanisms characterize the development of multimorbidity trajectories. A small proportion of patients has a high number of chronic health problems (MM11+) and keeps adding health problems during life. However, GP’s need to realise that more than one third of their patients accumulate four or more chronic health problems (MM4-5 and MM6-10) during life.

Mortality cohort effects from mid-19th to mid-20th century Britain: did they exist?

PURPOSE

Identification is a central problem with age-period-cohort analysis. Because age + cohort = period, there is no unique solution to the linear effect using generalized linear modeling, but cohort effects have caused greater controversy than age and period effects. To illustrate the magnitude of cohort effects given the presence of collinearity, we reanalyze data from the seminal study by Kermack et al, with an update.

METHODS

Relative mortality data in England and Wales between year 1845 and 1995 were analyzed using partial least squares regression. There were seven age groups ranging from 5 to 74 years old and 16 periods with 22 cohorts.

RESULTS

Our reanalysis seemed to support the existence of cohort effects in the mortality trends. Period and cohort effects were generally consistent with changes in the social, economic, and environmental factors taking place in the last two centuries. Our analysis also showed a declining trend in period effects up to 1950s.

CONCLUSIONS

Partial least squares and related methods provide intuitive pointers toward the separation of linear age, period, and cohort effects. Because statistical algorithms cannot distinguish between relative and actual mortality rates, cohort effects may be underestimated because of contamination by negative age effects.

Year of birth effects in the historical decline of tuberculosis mortality: a reconsideration

Birth cohort patterns in mortality are often used to infer long-lasting impacts of early life conditions. One of the most widely accepted examples of a birth cohort effect is that of tuberculosis mortality before the late 1940s. However the evidential basis for claims of cohort-specific declines in tuberculosis mortality is very slight. Reanalysis of original or enhanced versions of datasets used previously to support claims of cohort effects in tuberculosis mortality indicated that: 1. where the initial decline in tuberculosis mortality occurred within the period of observation, onset of decline occurred simultaneously in many age groups, in a pattern indicative of 'period' not cohort-dependent effects. 2. there was little evidence of 'proportional hazard'-type cohort patterns in tuberculosis mortality for any female population studied. Therefore any mechanisms proposed to underlie this type of cohort pattern in male mortality must be sex-specific. 3. sex ratios of tuberculosis mortality at older ages peaked in cohorts born around 1900, and resembled cohort sex ratios of lung cancer mortality. This analysis indicates that age-specific patterns in the decline in tuberculosis mortality before 1950 are unlikely to reflect improvements in early life conditions. The patterns observed are generally more consistent with the influence of factors that reduced mortality simultaneously in most age groups. Additional influences, possibly smoking habits, impeded the decline of tuberculosis in older adult males, and produced the sex-specific shifts in age distributions of mortality that were previously interpreted as evidence of cohort-dependent mortality decline.

'If you feel that nobody wants you you'll withdraw into your own': Gypsies/Travellers, networks and healthcare utilisation

Gypsies and Travellers are the unhealthiest group in British society, suffering from higher levels of physical and mental illness, lower life expectancy and with low levels of healthcare utilisation. They also continue to experience the highest level of prejudice and discrimination in society. While studies indicate that social networks play an important role in shaping health beliefs and the response to symptoms, evidence on the influence of networks on health is unclear and contradictory. This article draws on social network theory and research into the relation between discrimination and health to critically examine how networks mediate between collective experiences of racism and health-related behavior. Qualitative interviews with 39 adult Gypsies and Travellers were conducted in the South-East of England to explore the wider structural and institutional context and the influence those contexts play in shaping health beliefs and decisions whether to access formal health services. The findings indicate that the influence networks play in shaping health behaviour is dependent on the particular social context of the group and its status in relation to wider social structures, making generalization problematic.

Genomics and Population Health

Imagine being able to find out how a drug will affect you before you take it... receiving a medication that is specifically tailored to treat your disease, while minimizing your risk of developing adverse effects. Although a person’s environment, diet, and general state of health can all influence how he or she responds to medicines, another important factor is genes. Pharmacogenetics is the study of how your genes affect the way your body responds to a medicine. Pharmacogenetics helps to determine what the right medicine is for you, based on your own genes.1 The Pharmacogenetics and Pharmacogenomics Knowledge Base http://www.pharmgkb.org/resources/education/phar-genetics.jsp.

The ‘Golden Generations’ in Historical Context

Assumptions about future mortality are more important than those for factors such as fertility, migration, disability trends or real interest rates for cost projections of the U.S. Old Age, Survivors, Disability and Health Insurance scheme. Recently, one factor has been assumed to be the key driver of future mortality in both official British population projections and actuarial ones: a ‘cohort effect’ associated with a group who were born in a period centred on the early 1930s who have been identified as having experienced particularly rapid improvements in mortality rates and are often referred to as the ‘golden generations’ or ‘golden cohorts’. The concept of ‘cohort effects’ is discussed; limitations of national-level cohort data considered; and methods for identifying such effects are reviewed. Particular attention is given to the analysis of populations which have been identified as having clear cut cohort effects; those of Britain and Sweden in the later part of the nineteenth century and early twentieth century, as well as the contemporary British population. The likely magnitude of such effects is discussed using a stylised model to assess the extent to which members of the ‘golden generations’ are especially privileged.

Social inequality and health: the role of social capital

The aim of the article is to examine whether and to what degree the unequal distribution of social capital in the population explains the relationship between socioeconomic position and health in Norway. Theoretical insight and empirical evidence seem to suggest that social capital mediates the effect of socioeconomic position on health outcomes. However, only a few studies have addressed this question and those that have done so have used few and simple indicators of social capital. This study is based on a nationwide cross-sectional survey (N = 3190) commissioned by Statistics Norway. The survey was designed to cover a comprehensive set of variables measuring different aspects of the theoretical construct of social capital. Two health outcomes, self-perceived health and longstanding illness, were analysed. The results showed that the mediating role of social capital between socioeconomic position and health was negligible for both health outcomes. After controlling for socio-demographic variables and socioeconomic position, only neighbourhood satisfaction and generalised trust showed a significant association with self-perceived health, whereas none of the social capital variables had any significant association with longstanding illness. Some theoretical and methodological implications of the results are discussed.

Understanding the rapid increase in life expectancy in South Korea

OBJECTIVES

We assessed life expectancy increases in the past several decades in South Korea by age and specific causes of death.

METHODS

We applied Arriaga's decomposition method to life table data (1970-2005) and mortality statistics (1983-2005) to estimate age- and cause-specific contributions to changes in life expectancy.

RESULTS

Reductions in infant mortality made the largest age-group contribution to the life expectancy increase. Reductions in cardiovascular diseases (particularly stroke and hypertensive diseases) contributed most to longer life expectancy between 1983 and 2005 (30% in males and 28% in females). Lower rates of stomach cancer, liver disease, tuberculosis, and external-cause mortality accounted for 30% of the male and 20% of the female increase in longevity. However, higher mortality from ischemic heart disease, lung and bronchial cancer, colorectal cancer, breast cancer, diabetes, and suicide offset gains by 10% in both genders.

CONCLUSIONS

Rapid increases in life expectancy in South Korea were mostly achieved by reductions in infant mortality and in diseases related to infections and blood pressure.

Reexamining the Dominance of Birth Cohort Effects on Mortality

The association between birth cohort and subsequent mortality has been of interest especially following publication of studies around 1930 of cohorts born up to the latter part of the nineteenth century, particularly for England and Wales. Updated results are presented for this population, together with those for two other cohorts, twentieth-century Japanese and British populations born about 1930, which have been identified as having particularly clear-cut birth cohort patterns, and which are used to underpin incorporation of cohort effects in both British official and actuarial mortality forecasts. Graphical methods used to identify cohort patterns are discussed. A number of limitations and difficulties are identified that mean that the conclusions about the predominance of cohort effects are less robust than often assumed. It is argued that alternative explanations should be considered and that the concentration on birth cohorts with particularly advantaged patterns may distort research priorities.

What can alienation theory contribute to an understanding of social inequalities in health?

This article examines both the contribution and the limitations of research that has sought to develop a causal understanding of the psychosocial dimension of inequalities in health. The article seeks to revive interest in Marx's theory of alienation in developing the case for an alternative materialist conceptualization that is able to postulate the pathways from alienation as a psychosocial generative structure to social inequalities in health outcomes within late modern societies.

Neighborhoods and disability in later life

This paper uses the US Health and Retirement Study to explore linkages between neighborhood conditions and stages of the disablement process among adults aged 55 years and older in the United States. We consider multiple dimensions of the neighborhood including the built environment as well as social and economic conditions. In doing so, we use factor analysis to reduce indicators into eight neighborhood scales, which we incorporate into two-level logistic regression models along with controls for individual-level factors. We find evidence that economic conditions and the built environment, but not social conditions, matter. Neighborhood economic advantage is associated with a reduced risk of lower body limitations for both men and women. We also find for men that neighborhood economic disadvantage is linked to increased chances of reporting personal care limitations, particularly for those aged 55-64 years, and that high connectivity of the built environment is associated with reduced risk of limitations in instrumental activities. Our findings highlight the distinctive benefits of neighborhood economic advantage early in the disablement process. In addition, findings underscore the need for attention in the design and evaluation of disability-prevention efforts to the benefits that accrue from more physically connected communities and to the potential harm that may arise in later life from living in economically disadvantaged areas.

Socioeconomic position and health: the differential effects of education versus income on the onset versus progression of health problems

This article seeks to elucidate the relationship between socioeconomic position and health by showing how different facets of socioeconomic position (education and income) affect different stages (onset vs. progression) of health problems. The biomedical literature has generally treated socioeconomic position as a unitary construct. Likewise, the social science literature has tended to treat health as a unitary construct. To advance our understanding of the relationship between socioeconomic position and health, and ultimately to foster appropriate policies and practices to improve population health, a more nuanced approach is required--one that differentiates theoretically and empirically among dimensions of both socioeconomic position and health. Using data from the Americans' Changing Lives Study (1986 through 2001/2002), we show that education is more predictive than income of the onset of both functional limitations and chronic conditions, while income is more strongly associated than education with the progression of both.

Individual-level measures of social capital as predictors of all-cause and cardiovascular mortality: a population-based prospective study of men and women in Finland

Individual-level social capital was assessed for prediction of mortality in a nationally representative study population aged 30-99 years at the baseline. A total of 90% of the original sample had participated in a comprehensive health examination (Mini-Finland Health Survey) in 1978-1980. After the first 5 years of the 24-year follow-up period, 1,196 of 3,014 men and 1,280 of 3,689 women died. Individual-level social capital was determined by factor analysis that revealed three factors: residential stability, leisure participation and interpersonal trust. Factor analysis showed a gender difference in leisure social participation. All-cause mortality and cardiovascular mortality were analyzed using Cox proportional hazard models. Adjusted for demographic, life style and biological risk factors, and for health and socio-economic status, leisure participation was associated with reduced all-cause mortality in men (hazard ratio, HR: 0.94; 95% confidence interval, CI: 0.89-1.00). This association seems to be related to economic status in men. Age modifies the effect of interpersonal trust on all-cause mortality in men. In women, leisure participation (HR: 0.96; 95% CI: 0.91-1.00) and interpersonal trust (HR: 0.69; 95% CI: 0.51-0.93) predicted all-cause mortality, and the latter also cardiovascular mortality (HR: 0.93; 95% CI: 0.86-1.00). The associations between individual-level social capital and mortality are gender- and age-related. Understanding the gender and age perspectives appears to be essential for better insight into the interrelations between social capital and health.

Linking social capital and self-rated health: A multilevel analysis of 11,175 men and women in Sweden

This multilevel study included 11,175 participants interviewed 2000-2002 in Sweden. The association between neighbourhood linking social capital (voting in national elections) and self-rated health was analysed. Individuals living in neighbourhoods with the lowest levels of linking social capital exhibited a significantly higher risk of poor health than individuals living in neighbourhoods with the highest levels of linking social capital, after adjustment for individual characteristics, including individual voting. The neighbourhood variance indicated significant differences in self-rated health between neighbourhoods. Both individuals and neighbourhoods need to be targeted in order to enhance people's health in neighbourhoods with low linking social capital.

Transforming the U.S. child health system

This paper presents a vision and rationale for reform of the U.S. child health system based on paradigmatic changes in the conceptualization of child health development. Reviewing well-known and well-documented accounts of how this system is under-performing, we suggest that a bold, well-defined, transformative, and long-term reform strategy is needed to address intractable problems in the underlying operating logic, organization, and financing of the current child health system. We conclude by considering an optimistic, long-term policy transformation agenda, building up emerging opportunities and changing realities in the United States and abroad.

"Social capital," GNP per capita, relative income, and health: an ecological study of 23 countries

The effects of social capital, income inequality, and absolute per capita income were investigated in an ecological analysis of 23 rich and poor countries. Trust was chosen as an indicator of social capital, and GNP (gross national product) per capita and Gini index measured absolute and relative income, respectively. These independent variables were analyzed in a linear regression model with the dependent variables adult mortality rate (25-64 years), life expectancy, and infant mortality rate (IMR). Separate analyses were performed for poor and rich countries as well as all countries combined. Social capital (trust) showed no significant association with the three health outcomes. A particularly strong relationship was found between Gini index and IMR for rich countries, and GNP per capita and life expectancy for all countries. In the group of poor countries, GNP per capita and Gini index in the same model were associated with IMR. The results contradict the suggested impact of social capital on health, and instead support the notion that economic factors such as absolute income and relative income distribution are of importance.

Association between gross domestic product throughout the life course and old-age mortality across birth cohorts: Parallel analyses of seven European countries, 1950–1999

Mortality levels of national populations have often been studied in relation to levels of gross domestic product (GDP) at time of death. Following the life course perspective, we assessed whether old-age mortality levels for subsequent cohorts are differentially associated with GDP levels prevailing at different ages of the cohorts. We used all-cause and cause-specific mortality data by sex, age at death (65-99), year at death (1950-1999), and year of birth (1865-1924) for Denmark, England and Wales, Finland, France, the Netherlands, Norway, and Sweden. Trends in national GDP per capita between 1865 and 1999 were reconstructed from historical national accounts data. Through Poisson regression analyses, we determined for each country both univariate and multivariate associations across five-year birth cohorts between mortality and GDP levels prevailing at time of death, and at earlier ages of the cohorts (i.e. 0-5, 6-19, 20-49, and 50-64). For the subsequent cohorts, levels of GDP at time of death were strongly inversely associated with all-cause mortality, especially among women, and among men in England and Wales, Finland, and France. In most countries, stronger associations were observed with GDP levels prevailing at earlier ages of the cohorts. After control for GDP at time of death, these associations remained. An independent association of GDP at earlier ages of the cohort was also observed for cause-specific mortality. The associations were negative for ischaemic heart diseases, cerebrovascular diseases, and stomach cancer. They were positive for prostate cancer, breast cancer, COPD (women), and lung cancer (women). GDP prevailing at ages 20-49 (men) and ages 50-64 (women) had the largest associations with old-age mortality. These findings suggest an independent, mostly negative effect of GDP prevailing at earlier ages of subsequent cohorts on old-age mortality. Socio-economic circumstances during adulthood and middle age seem more important in determining old-age mortality trends than those during infancy or childhood.

Social capital and mental health: an interdisciplinary review of primary evidence

An interdisciplinary interrogation of primary evidence linking social capital and mental health sought to establish: (1) 'quality of evidence' (assessed in terms of study design, methods used to address stated questions, rigor of data analysis, and logic and clarity of interpretation of results), and (2) applicability of the evidence to public health policy and practice with respect to mental health. It is found that social capital, a complex and compound construct, can be both an asset and a liability with respect to mental health of those in receipt of and those providing services and other interventions. The most meaningful assessment of social capital or components thereof may examine individual access to rather than possession of social capital, a property of groups, and therefore an ecological variable. Theoretical advances in research on social capital serve to identify mainly two types of social capital: bonding (between individuals in a group) and bridging (between groups). Each type of social capital has cognitive and/or structural component(s) and may operate at micro and/or macro level(s). Effective mental health policy and service provision may build or strengthen bridging social capital and benefit from both bonding and bridging social capital where either or both exist. Established indicators of social capital are amenable to quantitative and qualitative assessment, preferably in tandem. However studies that employ combined research design are rare or non-existent. Interdisciplinary multi-method investigations and analyses are called for in order to unravel mechanisms whereby social capital and mental health might be meaningfully associated.

Contribution of primary care to health systems and health

Evidence of the health-promoting influence of primary care has been accumulating ever since researchers have been able to distinguish primary care from other aspects of the health services delivery system. This evidence shows that primary care helps prevent illness and death, regardless of whether the care is characterized by supply of primary care physicians, a relationship with a source of primary care, or the receipt of important features of primary care. The evidence also shows that primary care (in contrast to specialty care) is associated with a more equitable distribution of health in populations, a finding that holds in both cross-national and within-national studies. The means by which primary care improves health have been identified, thus suggesting ways to improve overall health and reduce differences in health across major population subgroups.