Measures of physical functioning are among the strongest predictors of mortality, but no previous study has assessed whether the predictive value of such measures varies by race/ethnicity, as has been done for the simple self-rated health question. The current study tests whether the relationship between two measures of physical functioning (the number of self-reported functional limitations and measured walking speed) and mortality is weaker (has a lower hazard ratio) for Latinos and blacks than for whites. Data were drawn from the 1998–2014 waves of the Health and Retirement Study, with mortality follow-up through 2016. We used Cox hazard models with household random effects to test for interactions between race/ethnicity and these measures of physical functioning and verified earlier findings for self-rated health. The number of self-reported functional limitations is significantly related to mortality for all racial/ethnic groups, but has a substantially lower hazard ratio for blacks and Latinos than for whites, as hypothesized. This hazard ratio remains lower for blacks and Latinos after adjustment for sociodemographic characteristics and health conditions. These findings suggest that the higher rates of functional limitations observed among Latinos and blacks compared with whites may reflect a history of strenuous physical work, inadequately controlled pain, lower leisure-time physical activity, or untreated/under-treated mobility problems that can lead to reduced physical performance without necessarily having a substantial effect on mortality risk. On the other hand, we do not detect significant racial/ethnic differences in the association between measured walking speed and subsequent mortality. This may be the result of the smaller sample size for the walking speed tests, the more nuanced nature of the continuous walking speed measure, or the fact that the walking speed test captures only a subset of the limitations included in the self-reports.

Background: Inequalities in mortality are often attributed to socioeconomic differences in education level, income, and wealth. Low socioeconomic status (SES) is generally related to worse health and survival across the life course. Yet, disadvantaged people are also more likely to hold jobs requiring heavy physical labor, repetitive movement, ergonomic strain, and safety hazards.

Objective: We examine the link between primary lifetime occupation, together with education and net worth, on survival among older adults in Mexico.

Methods: We use data from four waves (2001, 2003, 2012, and 2015) of the Mexican Health and Aging Study (MHAS). We estimate age-specific mortality rates for ages 50 and over using a hazards model based on a two-parameter Gompertz function.

Results: Primary lifetime occupations have a stronger association with survival for women than men. Women with higher socioeconomic status have significantly lower mortality rates than lower status women, whether SES is assessed in terms of schooling, wealth, or occupation. Occupational categories are not jointly related to survival among men, even without controls for education and wealth. There are significant survival differences by wealth among men, but no disparities in mortality by education.

Conclusions: Consistent with recent studies of the Mexican population, we fail to find the expected gradient in the association between some measures of SES and better survival among men.

Contribution: Our estimates extend this anomalous pattern among Mexican men to another dimension of SES, occupation. SES differentials in mortality are substantially larger for Mexican women, highlighting an important gender disparity.

Background: 

Foreign-born women have heavier infants than US-born women, but it is unclear whether this advantage persists across generations for all races and ethnicities.

Methods: 

Using 1971-2015 Florida birth records, we linked records of female infants within families to assess intergenerational changes in birthweight and prevalence of low birthweight by grandmother’s race, ethnicity and foreign-born status. We also assessed educational gradients in low birthweight in two generations.

Results: 

Compared to daughters of US-born black women, daughters of foreign-born black women had substantially higher birthweights (3,199 v. 3,083 grams) and lower prevalence of low birthweight (7.8% v. 11.8%). Daughters of foreign-born Hispanic women had moderately higher birthweights (3,322 v. 3,268 grams) and lower prevalence of low birthweight (4.5% v. 6.2%) than daughters of US-born Hispanic women. In the next generation, a Hispanic foreign-origin advantage persisted in low birthweight prevalence (6.1% v. 7.2%), but the corresponding black foreign-origin advantage was almost eliminated (12.2% v. 13.1%). Findings were robust to adjustment for sociodemographic and medical risk factors. In contrast to patterns for other women, the prevalence of low birthweight varied little by maternal education for foreign-born black women. However, a gradient emerged among their US-born daughters.

Conclusions: 

The convergence of birthweight between descendants of foreign-born and US-born black women is consistent with theories positing that lifetime exposure to discrimination and socioeconomic inequality is associated with adverse health outcomes for black women. The emergence of a distinct educational gradient in low birthweight prevalence between generations underscores hypothesized adverse effects of multiple dimensions of disadvantage.

Quantification of biological aging is of interest in gerontology as a means to surveil aging rates in the population and to evaluate the effects of interventions to increase healthy life span. Analysis of proposed methods to quantify biological aging has focused on samples of midlife or mixed-age adults in the West. Research is needed to test whether quantifications of biological aging can differentiate aging rates among older adults and if quantifications of biological aging developed in Western samples can differentiate aging rates in non-Western populations. We conducted analysis of Klemera-Doubal method (KDM) Biological Age and homeostatic dysregulation measures of biological aging developed in the U.S. NHANES and tested in a sample of older Taiwanese adults in the Social Environment and Biomarkers of Aging Study. We conducted analysis of physical and cognitive function and mortality, comparing quantifications of biological aging to a biomarker index based on norms within our analysis sample and to participants’ ratings of their own health. Results showed that quantifications of biological aging (a) predicted differences in physical and cognitive function and in mortality risk among Taiwanese older adults and (b) performed as well as a traditional biomarker index and participant self-rated health for prediction of these outcomes.

The Social Environment and Biomarkers of Aging Study (SEBAS) was a joint undertaking between the Taiwan Health Promotion Administration, Ministry of Health and Welfare (formerly the Taiwan Provincial Institute of Family Planning), and Princeton and Georgetown Universities, with notable contributions from others over the life of the project.

The very extensive data that were collected as part of the ongoing Taiwan Longitudinal Study of Aging (TLSA) provided a strong foundation for the underlying research questions: (1) what are the reciprocal relationships among health, the social environment, and exposure to challenge and (2) what can be learned from biomarkers about the pathways and mechanisms through which those relationships operate. The TLSA data – the first round was done in 1989 – comprised self-reported information on demographic characteristics, health and health-related behaviors, occupational and residential histories, participation in social activities, economic and educational status, and emotional and instrumental support (Chang et al. 2008; Taiwan Provincial Institute of Family Planning and Population Studies Center and Institute of Gerontology, University of Michigan 1989). The goal with the SEBAS was to update information from the most recent round of TLSA, to obtain information on exposure to stressors, and to collect measurements and specimens from the TLSA participants that would then be used to obtain biomarkers.

At the time the project began, few psychosocial surveys included the collection of biomarkers; SEBAS might have been the first to do so on a countrywide representative sample (albeit one limited to an older set of participants). As described below, the choice of biomarkers was modeled on the MacArthur Study of Successful Aging (Chang et al. 2008), which used the idea of allostatic load (McEwen and Stellar 1993) to understand how life’s challenges play out at the physiological level.

The initial pretest for SEBAS was performed in 1997–1998 (Weinstein et al. 2003); the first round was fielded in 2000 (Goldman et al. 2003, 2006) and the final round, which as described below collected performance assessments and self-reported information about health status, was completed in 2016.

Although declarative memory declines with age, sex and education might moderate these weaknesses. We investigated effects of sex and education on nonverbal declarative (recognition) memory in 704 older adults (aged 58–98, 0–17 years of education). Items were drawings of real and made-up objects. Age negatively impacted declarative memory, though this age effect was moderated by sex and object-type: it was steeper for males than females, but only for real objects. Education was positively associated with memory, but also interacted with sex and object-type: education benefited women more than men (countering the age effects, especially for women), and remembering real more than made-up objects. The findings suggest that nonverbal memory in older adults is associated negatively with age but positively with education; both effects are modulated by sex, and by whether learning relates to preexisting or new information. The study suggests downstream benefits from education, especially for girls.

We demonstrate widening socioeconomic disparities in perceived economic distress among Americans, characterized by increasing distress at the bottom and improved perceptions at the top of the socioeconomic ladder. We then assess the extent to which hardships related to the Great Recession account for the growing social disparity in economic distress. Based on the concept of loss aversion, we also test whether the psychological pain associated with a financial loss is greater than the perceived benefit of an equivalent gain. Analyses are based on longitudinal survey data from the Midlife Development in the US study. Results suggest that widening social disparities in perceived economic distress between the mid-2000s and mid-2010s are explained in part by differential exposure to hardships related to the Great Recession, the effects of which have lingered even four to five years after the recession officially ended. Yet, auxiliary analyses show that the socioeconomic disparities in economic distress widened by nearly as much (if not more) during the period from 1995–96 to 2004–05 as they did during the period in which the recession occurred, which suggests that the factors driving these trends may have already been in motion prior to the recession. Consistent with the loss aversion hypothesis, perceptions of financial strain appear to be somewhat more strongly affected by losses in income/assets than by gains, but the magnitude of the differentials are small and the results are not robust. Our findings paint a dismal portrait of a growing socioeconomic divide in economic distress throughout the period from the mid-1990s to the mid-2010s, although we cannot say whether these trends afflict all regions of the US equally. Spatial analysis of aggregate-level mortality and objective economic indicators could provide indirect evidence, but ultimately economic “despair” must be measured subjectively by asking people how they perceive their financial situations.

Apolipoprotein E (APOE) genotype is believed to play a role in the onset of dementia, though less is known about its relationship with non-pathogenic age-related cognitive decline. We assessed whether APOE was a risk factor for cognitive decline among older Taiwanese adults using nationally representative data. General cognition was measured longitudinally over eleven years; domain-specific cognitive assessments of working memory, declarative learning and three aspects of attention (executive function, alerting, and orientation) were performed once. Having at least one risky APOE allele was associated with more rapid longitudinal cognitive decline compared to those with no risky alleles. Some evidence from the cross-sectional analysis of domain-specific cognitive assessments suggested that APOE genotype may be more closely associated with working memory and declarative learning than with attention. Most genetic studies of cognition include only populations of European descent; extension is crucial. This study confirmed the association between APOE genotype and the rate of cognitive decline in a predominantly Han Chinese population. Additional studies on diverse populations are warranted.

Although there is little dispute about the impact of the US opioid epidemic on recent mortality, there is less consensus about whether trends reflect increasing despair among American adults. The issue is complicated by the absence of established scales or definitions of despair as well as a paucity of studies examining changes in psychological health, especially well-being, since the 1990s. We contribute evidence using two cross-sectional waves of the Midlife in the United States (MIDUS) study to assess changes in measures of psychological distress and well-being. These measures capture negative emotions such as sadness, hopelessness, and worthlessness, and positive emotions such as happiness, fulfillment, and life satisfaction. Most of the measures reveal increasing distress and decreasing well-being across the age span for those of low relative socioeconomic position, in contrast to little decline or modest improvement for persons of high relative position.

We evaluate the variability in estimates of self-reported physical limitations by age across four nationally representative surveys in the US. We consider its implications for determining whether, as previous literature suggests, the US estimates reveal limitations at an earlier age than in three countries with similar life expectancy: England, Taiwan, and Costa Rica. Based on cross-sectional data from seven population-based surveys, we use local mean smoothing to plot self-reported limitations by age for each of four physical tasks for each survey, stratified by sex. We find substantial variation in the estimates in the US across four nationally-representative surveys. For example, one US survey suggests that American women experience a walking limitation 15 years earlier than their Costa Rican counterparts, while another US survey implies that Americans have a 4-year advantage. Differences in mode of survey may account for higher prevalence of limitations in the one survey that used a self-administered mail-in questionnaire than in the other surveys that used in-person or telephone interviews. Yet, even among US surveys that used the same mode, there is still so much variability in estimates that we cannot conclude whether Americans have better or worse function than their counterparts in the other countries. Seemingly minor differences in question wording and response categories may account for the remaining inconsistency. If minor differences in question wording can result in such extensive variation in the estimates within a given population, then lack of comparability is likely to be an even greater problem when examining results across countries that do not share the same language or culture. Despite the potential utility of self-reported physical function within a survey sample, our findings imply that absolute estimates of population-level prevalence of self-reported physical limitations are unlikely to be strictly comparable across countries—or even across surveys within the same population.

The chapter first reviews extant literature on educational gradients in physiological dysregulation. Prior studies suggested there is an inverse relationship between education and risk, although the association may be weaker at the oldest ages and stronger among whites than blacks; the educational gradient may differ by country; and sex differences in the educational gradient may depend on the context. The chapter then presents new comparative analyses of the relationship between physiological dysregulation and education based on data from five countries (United States, England, Russia, Costa Rica, and Taiwan). Large educational differences were found in dysregulation in Russia, US white men, US black women, and English white women. The finding that the educational differential among US women is larger for blacks than for whites appears to be sensitive to how one defines “high” education. Using race-specific cutoffs, the education gradient did not differ significantly between black and white women.

There is no doubt that economic inequality in the US has increased over the last several decades (Piketty, Saez, and Zucm 2016; Congressional Budget Office 2013). Diminished labor market opportunities and the ensuing decline in (inflation‐adjusted) economic fortunes for the least educated Americans have been blamed for initiating a cascade of consequences culminating in rising mortality related to drugs, alcohol, and suicide (Case and Deaton 2017; 2015)—collectively referred to as “deaths of despair” (Khazan 2015; Case 2015; Monnat 2016). The health effects are evident in overall mortality as well: socioeconomic disparities in life expectancy have widened dramatically over this period (Chetty et al. 2016b; Bosworth, Burtless, and Zhang 2016), particularly among non‐Latino whites (Olshansky et al. 2012; Sasson 2016). Beyond its effects on health, inequality1 can have far‐reaching consequences for society as a whole, for example, by compromising social trust and cohesion and jeopardizing the effectiveness of social institutions (Kawachi and Berkman 2000; Kawachi et al. 1997). Indeed, arguments related to growing inequality have been invoked to explain many of the worrisome trends not only in mortality, but in a broader range of health outcomes, as well as social and political phenomena.

Working memory (WM), which underlies the temporary storage and manipulation of information, is critical for multiple aspects of cognition and everyday life. Nevertheless, research examining WM specifically in older adults remains limited, despite the global rapid increase in human life expectancy. We examined WM in a large sample (N=754) of healthy older adults (aged 58-89) in a non-Western population (Chinese speakers) in Taiwan, on a digit n-back task. We tested the influence not only of age itself and of load (1-back vs. 2-back), but also effects of both sex and education, which have been shown to modulate WM abilities. Mixed-effects regression revealed that, within older adulthood, age negatively impacted WM abilities (with linear, not nonlinear, effects), as did load (worse performance at 2-back). In contrast, education level was positively associated with WM. Moreover, both age and education interacted with sex. With increasing age, males showed a steeper WM decline than females; with increasing education, females showed greater WM gains than males. Together with other findings, the evidence suggests that age, sex, and education all impact WM in older adults, but interact in particular ways. The results have both basic research and translational implications, and are consistent with particular benefits from increased education for women.

The increased risk for poor physical and mental health outcomes for older parents in Mexico who have an adult child living in the United States may contribute to an increased risk for cognitive impairment in this population. The objective of this study was to examine if older adults in Mexico who have one or more adult children living in the United States are more or less likely to develop cognitive impairment over an 11-year period compared to older adults who do not have any adult children living in the United States.

The hypothesis that the S allele of the 5-HTTLPR serotonin transporter promoter region is associated with increased risk of depression, but only in individuals exposed to stressful situations, has generated much interest, research and controversy since first proposed in 2003. Multiple meta-analyses combining results from heterogeneous analyses have not settled the issue. To determine the magnitude of the interaction and the conditions under which it might be observed, we performed new analyses on 31 data sets containing 38 802 European ancestry subjects genotyped for 5-HTTLPR and assessed for depression and childhood maltreatment or other stressful life events, and meta-analysed the results. Analyses targeted two stressors (narrow, broad) and two depression outcomes (current, lifetime). All groups that published on this topic prior to the initiation of our study and met the assessment and sample size criteria were invited to participate. Additional groups, identified by consortium members or self-identified in response to our protocol (published prior to the start of analysis) with qualifying unpublished data, were also invited to participate. A uniform data analysis script implementing the protocol was executed by each of the consortium members. Our findings do not support the interaction hypothesis. We found no subgroups or variable definitions for which an interaction between stress and 5-HTTLPR genotype was statistically significant. In contrast, our findings for the main effects of life stressors (strong risk factor) and 5-HTTLPR genotype (no impact on risk) are strikingly consistent across our contributing studies, the original study reporting the interaction and subsequent meta-analyses. Our conclusion is that if an interaction exists in which the S allele of 5-HTTLPR increases risk of depression only in stressed individuals, then it is not broadly generalisable, but must be of modest effect size and only observable in limited situations.

We compare physical performance from three U.S. national surveys and nationally representative surveys in England, Taiwan, and Costa Rica. Method: For each performance test, we use local mean smoothing to plot the age profiles by sex and survey wave and then fit a linear regression model to the pooled data, separately by sex, to test for significant differences across surveys controlling for age and height. Results: Age profiles of performance vary across U.S. surveys, but levels of lung function (peak expiratory flow) and handgrip strength in the United States are as high as they are in the other three countries. Americans also perform as well on the chair stand test as the English and Costa Ricans, if not better, but exhibit slower gait speed than the English at most ages. Discussion: With the exception of walking speed, we find little evidence that older Americans have worse physical performance than their peers.

Using five waves of the Taiwanese Longitudinal Study of Aging (1996–2011), we investigate (1) the association between family members’ education and the age trajectories of individuals’ depressive symptoms and (2) gender differences in those relationships. Our examination is guided by several theoretical frameworks, including social capital, social control, age as leveler, and resource substitution. Nested models show that having a more educated father is associated with lower depressive symptoms, but the relationship disappears after controlling for respondent’s education. Including spouse’s education attenuates the coefficient for respondent’s education. A similar pattern appears when children’s education is added to the model. Among all the family members, children’s education has the strongest association with depressive symptoms, with a similar magnitude for both genders, although its strength gradually weakens as respondents age. Our findings suggest the importance of the transfer of resources from children to parents and how it may affect mental health at older ages.

We consider a broad set of variables used by social scientists and clinicians to identify the leading predictors of five‐year survival among American adults. We address a question not considered in earlier research: Do the strongest predictors of survival vary by age, sex or race/ethnicity? The analysis uses hazard models with 30 well‐established predictors to examine five‐year survival in the National Health and Nutrition Examination Survey. We find that the simple measure of self‐assessed health and self‐reported measures of functional ability and disability are the strongest predictors in all demographic groups, and are generally ranked considerably higher than biomarkers. Among the biomarkers, serum albumin is highly ranked in most demographic groups, whereas clinical measures of cardiovascular and metabolic function are consistently among the weakest predictors. Despite these similarities, there is substantial variation in the leading predictors across demographic groups, most notably by race and ethnicity

Social inequalities in health and disability are often attributed to differences in childhood adversity, access to care, health behavior, residential environments, stress, and the psychosocial aspects of work environments. Yet, disadvantaged people are also more likely to hold jobs requiring heavy physical labor, repetitive movement, ergonomic strain, and safety hazards. We investigate the role of physical work conditions in contributing to social inequality in mobility among older adults in Mexico, using data from the Mexican Health and Aging Survey (MHAS) and an innovative statistical modeling approach. We use data on categories of primary adult occupation to serve as proxies for jobs with more or less demanding physical work requirements. Our results show that more physically demanding jobs are associated with mobility limitations at older ages, even when we control for age and sex. Inclusion of job categories attenuates the effects of education and wealth on mobility limitations, suggesting that physical work conditions account for at least part of the socioeconomic differentials in mobility limitations in Mexico.

Researchers often rely on respondents' self-rated health (SRH) to measure social disparities in health, but recent studies suggest that systematically different reporting styles across groups can yield misleading conclusions about disparities in SRH. In this study, we test whether this finding extends to ethnic differences in self-assessments of health in particular domains. We document differences between US-born whites and four Latino subgroups in respondents' assessments of health in six health domains using data from the second wave of the Los Angeles Family and Neighborhood Survey (N = 1468). We use both conventional methods and an approach that uses vignettes to adjust for differential reporting styles.

The Social Environment and Biomarkers of Aging Study (SEBAS) is a nationally representative longitudinal survey of Taiwanese middle-aged and older adults. It adds the collection of biomarkers and performance assessments to the Taiwan Longitudinal Study of Aging (TLSA), a nationally representative study of adults aged 60 and over, including the institutionalized population. The TLSA began in 1989, with follow-ups approximately every 3 years; younger refresher cohorts were added in 1996 and 2003. The first wave of SEBAS, based on a sub-sample of respondents from the 1999 TLSA, was conducted in 2000. A total of 1023 respondents completed both a face-to-face home interview and, several weeks later, a hospital-based physical examination. In addition to a 12-h (7 pm–7 am) urine specimen collected the night before and a fasting blood specimen collected during the examination, trained staff measured blood pressure, height, weight and waist and hip circumferences. A second wave of SEBAS was conducted in 2006 using a similar protocol to SEBAS 2000, but with the addition of performance assessments conducted by the interviewers at the end of the home interview. Both waves of SEBAS also included measures of health status (physical, emotional, cognitive), health behaviours, social relationships and exposure to stressors. The SEBAS data, which are publicly available at [ http://www.icpsr.umich.edu/icpsrweb/NACDA/studies/3792/version/5 ], allow researchers to explore the relationships among life challenges, the social environment and health and to examine the antecedents, correlates and consequences of change in biological measures and health.

This study examines whether frailty is associated with mortality independently of physiological dysregulation (PD) and, if so, which is the more accurate predictor of survival. Data come from the Social Environment and Biomarkers of Aging Study. We use Cox proportional hazard models to test the associations between PD, frailty, and 4- to 5-year survival. We use Harrell’s concordance index to compare predictive accuracy of the models. Both PD and frailty are significantly, positively, and independently correlated with mortality: Worse PD scores and being frail are associated with a higher risk of dying. The overall PD score is a more accurate predictor of survival than frailty, although model prediction improves when both measures are included. PD and frailty independently predict mortality, suggesting that the two measures may be capturing different aspects of the same construct and that both may be important for identifying individuals at risk for adverse health outcomes

Persons of Mexican origin and some other Latino groups in the United States have experienced a survival advantage compared with their non-Latino White counterparts, a pattern known as the Latino, Hispanic, or epidemiological paradox. However, high rates of obesity and diabetes among Latinos relative to Whites and continued increases in the prevalence of these conditions suggest that this advantage may soon disappear. Other phenomena, including high rates of disability in the older Latino population compared with Whites, new evidence of health declines shortly after migration to the United States, increasing environmental stressors for immigrants, and high-risk values of inflammatory markers among Latinos compared with Whites support this prediction. One powerful counterargument, however, is substantially lower smoking-attributable mortality among Latinos. Still, it is questionable as to whether smoking behavior can counteract the many forces at play that may impede Latinos from experiencing future improvements in longevity on a par with Whites.

Telomere length has generated substantial interest as a potential predictor of aging-related diseases and mortality. Some studies have reported significant associations, but few have tested its ability to discriminate between decedents and survivors compared with a broad range of well-established predictors that include both biomarkers and commonly collected self-reported data. Our aim here was to quantify the prognostic value of leukocyte telomere length relative to age, sex, and 19 other variables for predicting five-year mortality among older persons in three countries. We used data from nationally representative surveys in Costa Rica (N = 923, aged 61+), Taiwan (N = 976, aged 54+), and the U.S. (N = 2672, aged 60+). Our study used a prospective cohort design with all-cause mortality during five years post-exam as the outcome. We fit Cox hazards models separately by country, and assessed the discriminatory ability of each predictor. Age was, by far, the single best predictor of all-cause mortality, whereas leukocyte telomere length was only somewhat better than random chance in terms of discriminating between decedents and survivors. After adjustment for age and sex, telomere length ranked between 15th and 17th (out of 20), and its incremental contribution was small; nine self-reported variables (e.g., mobility, global self-assessed health status, limitations with activities of daily living, smoking status), a cognitive assessment, and three biological markers (C-reactive protein, serum creatinine, and glycosylated hemoglobin) were more powerful predictors of mortality in all three countries. Results were similar for cause-specific models (i.e., mortality from cardiovascular disease, cancer, and all other causes combined). Leukocyte telomere length had a statistically discernible, but weak, association with mortality, but it did not predict survival as well as age or many other self-reported variables. Although telomere length may eventually help scientists understand aging, more powerful and more easily obtained tools are available for predicting survival.

There are large socioeconomic disparities in adult mortality in Russia, although the biological mechanisms are not well understood. With data from the study of Stress, Aging, and Health in Russia (SAHR), we use Gompertz hazard models to assess the relationship between educational attainment and mortality among older adults in Moscow and to evaluate biomarkers associated with inflammation, neuroendocrine function, heart rate variability, and clinical cardiovascular and metabolic risk as potential mediators of that relationship. We do this by assessing the extent to which the addition of biomarker variables into hazard models of mortality attenuates the association between educational attainment and mortality. We find that an additional year of education is associated with about 5% lower risk of age-specific all-cause and cardiovascular mortality. Inflammation biomarkers are best able to account for this relationship, explaining 25% of the education-all-cause mortality association, and 35% of the education-cardiovascular mortality association. Clinical markers perform next best, accounting for 13% and 23% of the relationship between education and all-cause and cardiovascular mortality, respectively. Although heart rate biomarkers are strongly associated with subsequent mortality, they explain very little of the education-mortality link. Neuroendocrine biomarkers fail to account for any portion of the link. These findings suggest that inflammation may be important for understanding mortality disparities by socioeconomic status.

Despite myriad efforts among social scientists, epidemiologists, and clinicians to identify variables with strong linkages to mortality, few researchers have evaluated statistically the relative strength of a comprehensive set of predictors of survival. Here, we determine the strongest predictors of five-year mortality in four national, prospective studies of older adults. We analyze nationally representative surveys of older adults in four countries with similar levels of life expectancy: England (n = 6113, ages 52+), the US (n = 2023, ages 50+), Costa Rica (n = 2694, ages 60+), and Taiwan (n = 1032, ages 53+). Each survey includes a broad set of demographic, social, health, and biological variables that have been shown previously to predict mortality. We rank 57 predictors, 25 of which are available in all four countries, net of age and sex. We use the area under the receiver operating characteristic curve and assess robustness with additional discrimination measures. We demonstrate consistent findings across four countries with different cultural traditions, levels of economic development, and epidemiological transitions. Self-reported measures of instrumental activities of daily living limitations, mobility limitations, and overall self-assessed health are among the top predictors in all four samples. C-reactive protein, additional inflammatory markers, homocysteine, serum albumin, three performance assessments (gait speed, grip strength, and chair stands), and exercise frequency also discriminate well between decedents and survivors when these measures are available. We identify several promising candidates that could improve mortality prediction for both population-based and clinical populations. Better prognostic tools are likely to provide researchers with new insights into the behavioral and biological pathways that underlie social stratification in health and may allow physicians to have more informed discussions with patients about end-of-life treatment and priorities.