Sense of neighborhood belonging and health: geographic, racial, and socioeconomic variation in Wisconsin

Background

Individuals' sense of belonging (SoB) to their neighborhood is an understudied psychosocial factor that may influence the association between neighborhood characteristics, health, and disparities across socio-demographic groups.

Methods

Using 2014-2016 data from the Survey of the Health of Wisconsin (SHOW, N = 1,706), we conduct a detailed analysis of SoB and health in an American context. We construct OLS and logistic regressions estimating belonging's association with general, physical, and mental health. We explore geographic, racial, and socioeconomic variation to understand both the differential distribution of SoB and its heterogeneous relationship with health.

Results

A higher SoB is positively associated with better physical, mental, and general health. White participants report higher SoB than Black participants, yet the association between SoB and mental health is strongest among participants of color and urban residents.

Conclusion

Sense of belonging to neighborhood significantly predicts many facets of health, with place and individual characteristics appearing to moderate this relationship. Racial, geographic, and socioeconomic disparities in belonging-health associations raise important questions about who benefits from the social, economic, and physical aspects of local communities.

Constructing Residential Histories in a General Population-Based Representative Sample

Research on neighborhoods and health typically measures neighborhood context at a single point in time. However, neighborhood exposures accumulate over the life course, influenced by both residential mobility and neighborhood change, with potential implications for estimating the impact of neighborhoods on health. Commercial databases offer fine-grained longitudinal residential address data that can enrich life-course spatial epidemiology research, and validated methods for reconstructing residential histories from these databases are needed. Our study draws on unique data from a geographically diverse, population-based representative sample of adult Wisconsin residents and the LexisNexis (New York, New York) Accurint, a commercial personal profile database, to develop a systematic and reliable methodology for constructing individual residential histories. Our analysis demonstrated that creating residential histories across diverse geographical contexts is feasible, and it highlights differences in the information obtained from available residential histories by age, education, race/ethnicity, and rural/urban/suburban residency. Researchers should consider potential address data availability and information biases favoring socioeconomically advantaged individuals and their implications for studying health inequalities. Despite these limitations, LexisNexis data can generate varied residential exposure metrics and be linked to contextual data to enrich research into the contextual determinants of health at varied geographic scales.

Understanding Geographic Disparities in Mortality

A rich literature shows that early-life conditions shape later-life outcomes, including health and migration events. However, analyses of geographic disparities in mortality outcomes focus almost exclusively on contemporaneously measured geographic place (e.g., state of residence at death), thereby potentially conflating the role of early-life conditions, migration patterns, and effects of destinations. We employ the newly available Mortality Disparities in American Communities data set, which links respondents in the 2008 American Community Survey to official death records, and estimate consequential differences based on the method of aggregation we use: the unweighted mean absolute deviation of the difference in life expectancy at age 50 measured by state of birth versus state of residence is 0.58 years for men and 0.40 years for women. These differences are also spatially clustered, and we show that regional inequality in life expectancy is higher based on life expectancies by state of birth, implying that interstate migration mitigates baseline geographic inequality in mortality outcomes. Finally, we assess how state-specific features of in-migration, out-migration, and nonmigration together shape measures of mortality disparities by state (of residence), further demonstrating the difficulty of clearly interpreting these widely used measures.

STICKING WITH THE UNION? LABOR UNION MEMBERSHIP, WORKING CONDITIONS, AND POSTRETIREMENT HEALTH IN THE MIDWEST

American Employment experiences over the past five decades have been shaped by growing prevalence of bad jobs – those that are precarious and offer few pension or health insurance benefits – and a marked decline in unionization. Previous health research has highlighted the deleterious implications of bad jobs and yielded mixed or inconclusive findings about union membership. However, most of this research focused on working-age adults, and few studies have examined the long-term impacts of working conditions and union membership. We fill this gap via data from the Wisconsin Longitudinal Study – a sample of men and women who graduated from Wisconsin high schools in 1957 and have been followed through their working years, past retirement, and into oldest-old ages. We estimated regression models examining the impact of union participation in 1975 on subsequent self-rated health and depressive symptoms (measured in 1993, 2004, and 2011). Our findings suggest that union participation was associated with poorer self-rated health in 1993 (OR=0.67, 95% CI (0.48, 0.96)), with a stronger negative effect for more active union members (OR=0.58, 95% CI (0.36, 0.96)), even after controlling for socioeconomic status in childhood and adulthood. This effect dissipated by 2004, when most WLS participants were nearing retirement and further diminished by 2011, when participants were in their 70s. We found no significant effects of union activity on depressive symptoms. Job characteristics and the historical decline in the prevalence and power of unions over the cohort’s lifetime provide important contexts for interpreting these results.

Social insurance programs and later-life mortality: Evidence from new deal relief spending

A growing body of research explores the long-run effects of social programs and welfare spending. However, evidence linking welfare support in early life with longevity is limited. We add to this literature by evaluating the effect of in-utero and early-life exposure to the largest increases in welfare spending in the US history under the New Deal programs. Using Social Security Administration death records linked with the 1940-census and spending data for 115 major cities, we show that the spending is correlated with improvements in old-age longevity. A treatment-on-treated calculation focused on a period when spending rose by approximately 1900 percent finds that a 100 percent rise in municipal spending in the year of birth is associated with roughly 3.5 months higher longevity. We show that these effects are not driven by endogenous selection of births, selective fertility, endogenous migration, and sample selection caused by endogenous data linking. Additional analysis suggests that rises in education and socioeconomic status are likely channels of impact.

Health, Wealth, and Voting Trajectories in Later Life

OBJECTIVES

Much of what we know about voting behaviors is based on cross-sectional comparisons of voters at different ages. This study draws on a unique linkage between the Wisconsin Longitudinal Study and state voter files to characterize voting trajectories in later life and explore their determinants.

METHODS

Using sequence analysis, we identify 5 voting typologies based on turnout and voting methods over 8 biennial elections. Using multinomial logistic and Poisson regressions, we examine the role of physical, cognitive, and mental health and wealth in shaping enfranchisement and civic participation at older ages.

RESULTS

Health and wealth are both positively associated with voter turnout, but the negative impact of poor health on voting declines with increasing wealth. Voting at the polls and early voting are more common among healthier older adults, whereas absentee voting is more common among older voters who are more affluent, less healthy, or both. Among those less wealthy, absentee methods mitigate the impact of poor health for previously active voters, but do not compensate for a lower turnout rate. In addition to physical and cognitive limitations, emotional difficulties and depression reduce turnout, particularly among the least wealthy.

DISCUSSION

In this sample of older, largely White, primarily Midwestern committed voters, civic participation at older ages is shaped by individual experiences with wealth and health across the life course as well as political structures that facilitate or restrict the ability of individuals to consistently participate in elections.

The Wisconsin Longitudinal Study: Overview, Data Linkages, and Future Plans

The WLS is a study of Wisconsin high school class of 1957 graduates, with follow-ups in 1964, 1975, 1993, 2004, 2011, and 2020. The data reflect the life course of the graduates (and their siblings), initially covering education, switching to family, career, and social participation in midlife, and physical and mental health, cognitive status, caregiving, and social support as respondents age. The WLS is linked to multiple administrative data sources including: parent earnings from state tax records (1957-60) and Social Security earnings and benefits for respondents; 1940 Census data; characteristics of high schools and colleges, employers, industries, and communities of residence; voting records from 2000-2018; Medicare claims; and the National Death Index. Efforts are underway to expand the racial/ethnic and educational composition of the WLS by supplementing the original sample with a new cohort of age-matched adults drawn from Wisconsin’s Black, Hispanic, Asian-American, and Native American communities.

From convergence to divergence: Lifespan variation in US states, 1959-2017

BACKGROUND

Large disparities in life expectancy exist across US states and the gaps have been widening in recent decades. Less is known about the lifespan variability - a measure that can provide important insights into mortality inequalities both between and within states.

METHOD

Using yearly lifetables from the United States Mortality Database, we explore geographic and temporal patterns in lifespan variation (unconditional and conditional on survival to age 10, 35 and 65) across US states between 1959 and 2017. We also examine the contribution of state differences in life expectancy to overall lifespan variation using standard decomposition techniques.

RESULTS

Despite overall convergence in lifespan variation across states over the last six decades, in more recent years there has been notable divergence. Gender-specific analyses show that lifespan variation was generally greater among males than among females; but this pattern reverses for mortality past age 65. Much of the state disparities in lifespan variation, unconditional and conditional on survival to age 10 and 35, were due to mortality differences under the age 65. Decomposition analysis shows that while within-state variability remains the primary driver of overall lifespan variation, the contribution of cross-state differences in life expectancy is growing.

CONCLUSIONS

Variation in longevity is greater within US States than between them, yet cross-states disparities in mortality are increasing. This likely reflects the long-term consequences of rising social, economic, and political stratification for health inequalities both within and across states.

Deaths, Disparities, and Cumulative (Dis)Advantage: How Social Inequities Produce an Impairment Paradox in Later Life

BACKGROUND

Research on health across the life course consistently documents widening racial and socioeconomic disparities from childhood through adulthood, followed by stabilization or convergence in later life. This pattern appears to contradict expectations set by cumulative (dis)advantage (CAD) theory. Informed by the punctuated equilibrium perspective, we examine the relationship between midlife health and subsequent health change and mortality and consider the impact of earlier socioeconomic exposures on observed disparities.

METHODS

Using the Health and Retirement Study, we characterize the functional impairment histories of a nationally-representative sample of 8,464 older adults between 1994-2016. We employ non-parametric and discrete outcome multinomial logistic regression to examine the competing risks of mortality, health change, and attrition.

RESULTS

Exposures to disadvantages are associated with poorer functional health in midlife and mortality. However, a higher number of functional limitations in midlife is negatively associated with the accumulation of subsequent limitations for white men and women and for Black women. The impact of educational attainment, occupation, wealth, and marriage on later life health differs across race and gender groups.

CONCLUSIONS

Observed stability or convergence in later-life functional health disparities is not a departure from the dynamics posited by CAD, but rather a result of the differential impact of racial and socioeconomic inequities on mortality and health at older ages. Higher exposure to disadvantages and a lower protective impact of advantageous exposures lead to higher mortality among Black Americans, a pattern which masks persistent health inequities later in life.

How are social determinants of health integrated into epigenetic research? A systematic review

OBJECTIVE

We systematically review the literature on social epigenetics, examining how empirical research to date has conceptualized and operationalized social determinants of health (SDOH).

METHODS

Using comprehensive search procedures, we identified studies that consider the impact of SDOH on DNA methylation (DNAm), the most common measure of epigenetic change in research on human adult populations. We analyzed the studies to determine: 1) which populations and environments have been investigated in the literature; 2) how SDOH are defined and operationalized; 3) which SDOH have been linked to DNAm; and 4) what lessons from the SDOH literature can be better integrated into future studies exploring the social determinants of health and epigenetic outcomes.

RESULTS

We identified 67 studies, with 39 to 8397 participants. The SDOH most commonly considered were early life socioeconomic exposures and early life trauma or mental health. Our review highlights four broad challenges: a) high dependence on convenience sampling, b) limited racial/ethnic, and geographic diversity in sampling frames, c) overreliance on individual sociodemographic characteristics as proxies for broader stratification processes, and d) a focus on downstream social determinants of health and individualized experiences with social stressors.

CONCLUSIONS

Future social epigenetics research should prioritize larger, more diverse and representative population-based samples and employ the SDOH framework to better inform the conceptualization of research questions and interpretation of findings. In particular, the simplified depiction of race/ethnicity, gender, and socioeconomic status as individual-level characteristics should be updated with an explicit acknowledgement that these characteristics are more accurately interpreted as cues used by society to differentiate subpopulations. Social epigenetics research can then more clearly elucidate the biological consequences of these social exposures for patterns of gene expression, subsequent disease etiology, and health inequities.

Where and When: Sharpening the lens on geographic disparities in mortality

Life course theories suggest that geographic disparities in mortality may reflect a history of place-based exposures rather than (or in addition to) contemporaneous exposures; yet, few studies examined early life place exposures and later life mortality in the US due to data limitations. The aim of this study is to assess and compare the importance of state of birth and state of residence in predicting mortality for adults over age 50 in the US. Using nationally representative data of nearly 100,000 adults over age 50 from the National Longitudinal Mortality Study, we estimated individual mortality risk using multi-level logistic regression with state of birth and state of residence as second-level random effects. We assessed whether state of residence and state of birth contributed to the variation in adult mortality. We also decomposed state-of-residence random effects to compare “movers” and “stayers.” Our results indicate that state of birth is a stronger predictor of age-, race/ethnicity- and sex-adjusted mortality in the US than state of residence at the time of death. The adult mortality profiles of many states are substantially impacted by the composition of “movers.” Failing to account for residential mobility has clouded our understanding of the patterns and causes of geographic differences in adult mortality. Measures of geographic residence across the life course can improve models of adult mortality in the US and inform interventions to address geographic disparities in longevity.

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State of birth is a stronger predictor of later age mortality than state of residence.

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Geographic inequalities in mortality are results from complex groupings of “movers” and “stayers”.

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Incorporating geographic residence across the life course improves models of adult mortality.

Gradual Change, Homeostasis, and Punctuated Equilibrium: Reconsidering Patterns of Health in Later Life

Longitudinal methods aggregate individual health histories to produce inferences about aging populations, but to what extent do these summaries reflect the experiences of older adults? We describe the assumption of gradual change built into several influential statistical models and draw on widely used, nationally representative survey data to empirically compare the conclusions drawn from mixed-regression methods (growth curve models and latent class growth analysis) designed to capture trajectories with key descriptive statistics and methods (multistate life tables and sequence analysis) that depict discrete states and transitions. We show that individual-level data record stasis irregularly punctuated by relatively sudden change in health status or mortality. Although change is prevalent in the sample, for individuals it occurs rarely, at irregular times and intervals, and in a nonlinear and multidirectional fashion. We conclude by discussing the implications of this punctuated equilibrium pattern for understanding health changes in individuals and the dynamics of inequality in aging populations.

Robust Respondents and Lost Limitations: The Implications of Nonrandom Missingness for the Estimation of Health Trajectories

OBJECTIVE

We offer a strategy for quantifying the impact of mortality and attrition on inferences from later-life health trajectory models.

METHOD

Using latent class growth analysis (LCGA), we identify functional limitation trajectory classes in the Health and Retirement Study. We compare results from complete case and full information maximum likelihood (FIML) analyses, and demonstrate a method for producing upper- and lower-bound estimates of the impact of attrition on results.

RESULTS

LCGA inferences vary substantially depending on the handling of missing data. For older adults who die during the follow-up period, the widely used FIML approach may underestimate functional limitations by up to 20%.

DISCUSSION

The most commonly used approaches to handling missing data likely underestimate the extent of poor health in aging populations. Although there is no single solution for nonrandom missingness, we show that bounding estimates can help analysts to better characterize patterns of health in later life.

The Immigrant Health Differential in the Context of Racial and Ethnic Disparities: The Case of Diabetes

PURPOSE

Social and economic disparities between racial/ethnic groups are a feature of the American context into which immigrants are incorporated, and a key determinant of population health. We ask whether racial/ethnic disparities in diabetes vary by nativity and whether native-immigrant disparities in diabetes vary by race and over time in the United States.

METHODS

Using the 2000-2015 National Health Interview Survey, we estimate logistic regressions to examine the interaction of race/ethnicity, nativity, and duration in the U.S. in shaping diabetes patterns.

RESULTS

Relative to their native-born co-ethnics, foreign-born Asian adults experience a significant diabetes disadvantage, while foreign-born Hispanic, Black, and White adults experience a significant advantage. Adjusting for obesity, education, and other covariates eliminates the foreign-born advantage for Black and White adults, but it persists for Hispanic adults. The same adjustment accentuates the disadvantage for foreign-born Asian adults. For Black and Hispanic adults, the protective foreign-born effect erodes as duration in the U.S. increases. For foreign-born Asian adults, the immigrant disadvantage appears to grow with duration in the U.S. Relative to native-born White adults, all non-white groups regardless of nativity see a diabetes disadvantage because the racial/ethnic disadvantage either countervails a foreign-born advantage or amplifies a foreign-born disadvantage.

DISCUSSION

Racial/ethnic differentials in diabetes are considerable, and are influenced by each group's nativity composition. Obesity and (for the foreign-born) time in the U.S. influence these disparities, but do not explain them. These findings underscore the importance of unmeasured, systemic determinants of health in America's race-conscious society.

A Quiescent Phase in Human Mortality? Exploring the Ages of Least Vulnerability

Demographic studies of mortality often emphasize the two ends of the lifespan, focusing on the declining hazard after birth or the increasing risk of death at older ages. We call attention to the intervening phase, when humans are least vulnerable to the force of mortality, and consider its features in both evolutionary and historical perspectives. We define this quiescent phase (Q-phase) formally, estimate its bounds using life tables for Swedish cohorts born between 1800 and 1920, and describe changes in the morphology of the Q-phase. We show that for cohorts aging during Sweden's demographic and epidemiological transitions, the Q-phase became longer and more pronounced, reflecting the retreat of infections and maternal mortality as key causes of death. These changes revealed an underlying hazard trajectory that remains relatively low and constant during the prime ages for reproduction and investment in both personal capital and relationships with others. Our characterization of the Q-phase highlights it as a unique, dynamic, and historically contingent cohort feature, whose increased visibility was made possible by the rapid pace of survival improvements in the nineteenth and twentieth centuries. This visibility may be reduced or sustained under subsequent demographic regimes.

Work Disability Among Native-born and Foreign-born Americans: On Origins, Health, and Social Safety Nets

Public debates about both immigration policy and social safety net programs are increasingly contentious. However, little research has explored differences in health within America's diverse population of foreign-born workers, and the effect of these workers on public benefit programs is not well understood. We investigate differences in work disability by nativity and origins and describe the mix of health problems associated with receiving Social Security Disability Insurance benefits. Our analysis draws on two large national data sources-the American Community Survey and comprehensive administrative records from the Social Security Administration-to determine the prevalence and incidence of work disability between 2001 and 2010. In sharp contrast to prior research, we find that foreign-born adults are substantially less likely than native-born Americans to report work disability, to be insured for work disability benefits, and to apply for those benefits. Overall and across origins, the foreign-born also have a lower incidence of disability benefit award. Persons from Africa, Northern Europe, Canada, and parts of Asia have the lowest work disability benefit prevalence rates among the foreign-born; persons from Southern Europe, Western Europe, the former Soviet Union, and the Caribbean have the highest rates.

Where does the neighborhood go? Trust, social engagement, and health among older adults in Baltimore City

Trust is often cited as a necessary predecessor of social engagement, and a public-health good. We question those suppositions through analysis of the life histories of lower-income older adults aging in place in Baltimore. These people desired to continue living independently, but also expressed a complex mix of trust and mistrust in their neighbors, neighborhoods, and broader environments. This was the product of interrelated processes of multilevel physical and social changes over time and space - and, we argue, often featured a "healthy mistrust" that pushed participants to pursue personally meaningful forms of social engagement, whether new or continued.

Life Expectancy Among U.S.-born and Foreign-born Older Adults in the United States: Estimates From Linked Social Security and Medicare Data

In recent decades, the geographic origins of America's foreign-born population have become increasingly diverse. The sending countries of the U.S. foreign-born vary substantially in levels of health and economic development, and immigrants have arrived with distinct distributions of socioeconomic status, visa type, year of immigration, and age at immigration. We use high-quality linked Social Security and Medicare records to estimate life tables for the older U.S. population over the full range of birth regions. In 2000-2009, the foreign-born had a 2.4-year advantage in life expectancy at age 65 relative to the U.S.-born, with Asian-born subgroups displaying exceptionally high longevity. Foreign-born individuals who migrated more recently had lower mortality compared with those who migrated earlier. Nonetheless, we also find remarkable similarities in life expectancy among many foreign-born subgroups that were born in very different geographic and socioeconomic contexts (e.g., Central America, western/eastern Europe, and Africa).

Geriatric syndromes and functional status in NSHAP: rationale, measurement, and preliminary findings

INTRODUCTION

The geriatric functional measures and syndromes collected 5 years apart in Waves 1 and 2 of the National Social Life, Health, and Aging Project (NSHAP) data set included: difficulty with activities of daily living and instrumental activities of daily living, the timed up and go, a 3-m timed walk, repeated chair stands, self-reported physical activity, accelerometry-assessed (in)activity, falls, fractures, and frailty. The purpose of this paper was to describe the data collection methods and report preliminary population estimates for each measures.

METHOD

Frequencies, means, or medians were estimated for each measure stratified by age and gender, using the age-eligible samples in Wave 1 (n = 3,005) and Wave 2 (n = 3,196). An adapted phenotypic frailty scale was constructed in the sample common to both waves (n = 2,261). Changes over 5 years were reported for four measures common to both waves.

RESULTS

The functional measures worsened with age (p < .001). The syndromes were more prevalent with age except "all fractures" (p value range < .001-.03). Functional measures were worse among females than males except chair stand performance and the accelerometry-assessed (in)activity measures (p value range < .001-.01). The syndromes were more common among females than males except Wave 2 falls and Wave 2 hip fractures (p value range < .001-.03). Changes from Wave 1 to 2 revealed 11.5%-25.2% of individuals reported better health and 21.3%-44.7% reported worse health.

DISCUSSION

The NSHAP provides a comprehensive assessment of geriatric health. Our findings are consistent with the literature and support the construct of the study measures.

Returns on Lifetime Investments in Children in Egypt

Parental expectations about the companionship and assistance they will receive in later life from their children are key considerations in family formation decisions. We explore patterns of parents’ investment and the support and contact they receive from adult children in Egypt, where fertility is falling and sources of support at all life stages are in flux. Using data from a survey of older adults in Ismailia governorate, we consider parents’ past investments in childbearing, child survival, and children’s education and marriage, as well as recent assistance to adult children via housing, care for grandchildren, gifts, and money. The returns from children considered include economic assistance, instrumental support, and visits. Most parental investments are associated with frequent visits from children. The assistance children provide to parents is gendered: sons tend to provide economic transfers, whereas daughters tend to provide instrumental help. A greater number of surviving children is most strongly associated with parents’ receipt of multiple types of later-life returns. Investments in children’s education and marriage are not associated with assistance, but recent assistance to children—especially economic transfers and provision of housing—is associated with receiving instrumental assistance from adult children.

Moving Considerations

Residential proximity is an important indicator of family members’ availability to provide assistance to each other. We investigate proximity-enhancing moves by older parents and their children and the reasons for such moves. Using the 2000–2004 waves of the Health and Retirement Study, we fit multinomial logit models examining 2-year residential transitions for parents and children living 10 or more miles apart at baseline. Our results show that family members collectively adjust intergenerational proximity to facilitate mutual support. Despite the common assumption that older parents move closer to their children to receive assistance, more than two thirds of all proximity-enhancing moves are made by adult children. While greater anticipated longevity raises the probability that older parents will move closer to their children, parents’ anticipated longevity does not influence children’s moving decisions. Including individual variability in anticipated longevity in the life course framework helps account for relocation that precedes declines in health or increases in the need for support.

Gender and Material Transfers between Older Parents and Children in Ismailia, Egypt

In Egypt, kin relations have been governed by a patriarchal contract, which defines expectations for intergenerational support along gendered lines. Social changes may be disrupting these customs and bringing attention to the ways gender may influence intergenerational support in rapidly changing contexts. Using data from 4,465 parent-child dyads in Ismailia, Egypt, we examined whether intergenerational material transfers favored women over men and whether gaps in needs and endowments accounted for gender differences in transfers. Fathers gave children money and goods more often than did mothers; mothers received material transfers from children more often than did fathers. Compared to sons, daughters made transfers to parents less often and received transfers from parents more often. We found residual advantages to mothers and daughters, even adjusting for differential needs and endowments. Findings corroborate persistent norms of gender complementarity, patrilocal endogamy, and reciprocation for women's caregiving, despite changes that have threatened patriarchal rules of exchange.

THE HEALTH OF OLDER WOMEN AFTER HIGH PARITY IN TAFT, IRAN

High parity has been hypothesised to lead to a shorter and less healthy life. Using the 2007 Taft Ageing Health and Fertility Survey consisting of 696 women aged 50-79, this paper examines the extent to which women's health in middle and older ages is affected by their childbearing histories. The results show that high parity (> 8) is associated with a reduction of GP-rated health by 0.094 points on a scale from 1 to 10. These health reductions are four times as large as those of an extra year of age, and are robust to controlling for birth interval, age, area of residence, education, marital status, work history, economic satisfaction and surviving daughters. There is a positive but curvilinear relationship between shorter birth intervals (< 2 years) and GP-rated health accounting for socio-demographic factors. Our analysis suggests that parity and birth intervals, along with socio-demographic characteristics, affect women's well-being in later life.

Parity and parents' health in later life: the gendered case of Ismailia, Egypt

We investigate the relationship between reproduction and functional health in later life among women and men in the resource-poor and gender-stratified setting of Ismailia governorate, Egypt. Analyses of survey data collected in 2003 show a statistically significant positive association between parity and difficulty with activities of daily living (ADLs), controlling for demographic and socio-economic factors and other co-morbid conditions. We also find that the number of daughters (but not sons) is associated with worse physical functioning, and this association is more pronounced for older fathers than for older mothers. Our results indicate that both biological and social pathways link fertility and later-life health in this context, and that prescribed familial roles may underlie the differential impact of sons and daughters on the health of mothers and fathers in later life.

Propositional density and cognitive function in later life: findings from the Precursors Study

OBJECTIVES

We used longitudinal data from the Johns Hopkins Precursors Study to test the hypothesis that written propositional density measured early in life is lower for people who develop dementia categorized as Alzheimer's disease (AD). This association was reported in 1996 for the Nun Study, and the Precursors Study offered an unprecedented chance to reexamine it among respondents with different gender, education, and occupation profiles.

METHODS

Eighteen individuals classified as AD patients (average age at diagnosis: 74) were assigned 2 sex-and-age matched controls, and propositional density in medical school admission essays (average age at writing: 22) was assessed via Computerized Propositional Idea Density Rater 3 linguistic analysis software. Adjusted odds ratios (ORs) for the matched case-control study were calculated using conditional (fixed-effects) logistic regression.

RESULTS

Mean propositional density is lower for cases than for controls (4.70 vs. 4.99 propositions per 10 words, 1-sided p = .01). Higher propositional density substantially lowers the odds of AD (OR = 0.16, 95% confidence interval = 0.03-0.90, 1-sided p = .02).

DISCUSSION

Propositional density scores in writing samples from early adulthood appear to predict AD in later life for men as well as women. Studies of cognition across the life course might beneficially incorporate propositional density as a potential marker of cognitive reserve.

The implications of increased survivorship for mortality variation in aging populations

The remarkable growth in life expectancy during the twentieth century inspired predictions of a future in which all people, not just a fortunate few, will live long lives ending at or near the maximum human life span. We show that increased longevity has been accompanied by less variation in ages at death, but survivors to the oldest ages have grown increasingly heterogeneous in their mortality risks. These trends are consistent across countries, and apply even to populations with record-low variability in the length of life. We argue that as a result of continuing improvements in survival, delayed mortality selection has shifted health disparities from early to later life, where they manifest in the growing inequalities in late-life mortality.

Population aging and international development: addressing competing claims of distributive justice

To date, bioethics and health policy scholarship has given little consideration to questions of aging and intergenerational justice in the developing world. Demographic changes are precipitating rapid population aging in developing nations, however, and ethical issues regarding older people's claim to scarce healthcare resources must be addressed. This paper posits that the traditional arguments about generational justice and age-based rationing of healthcare resources, which were developed primarily in more industrialized nations, fail to adequately address the unique challenges facing older persons in developing nations. Existing philosophical approaches to age-based resource allocation underemphasize the importance of older persons for developing countries and fail to adequately consider the rights and interests of older persons in these settings. Ultimately, the paper concludes that the most appropriate framework for thinking about generational justice in developing nations is a rights-based approach that allows for the interests of all age groups, including the oldest, to be considered in the determination of health resource allocation.