Daily exposure to stressors, daily perceived severity of stress, and mortality risk among US adults.

Prior studies of perceived stress and mortality have yielded mixed results, but most are based on one-time measurements of perceived stress. We use daily diary data from the Midlife in the United States study to measure exposure to stressors and perceived severity of stress and investigate their associations with mortality. We also explore whether the associations vary by age and assess whether the associations are stronger for extrinsic than intrinsic mortality, which is more likely to be aging-related. The analysis included 4,756 observations for 2,915 respondents aged 21-95 who participated in at least one of three waves (1996-97, 2004-09, 2017-19) of the National Study of Daily Experiences. Participants reported daily stressors and perceived severity on 8 consecutive evenings at each wave. Mortality was followed through December 31, 2021. In fully-adjusted models, daily exposure to stressors was associated with mortality, but only at younger ages (HR = 1.20 per SD at age 50, 95% CI: 1.01‒1.42). The association was slightly stronger for extrinsic (HR = 1.31 per SD at age 50, 95% CI: 1.01‒1.69) than for intrinsic mortality, which was not significant (HR = 1.24 per SD at age 50, 95% CI: 0.98‒1.56). When we used an alternative measure of daily perceived severity of stress, the demographic-adjusted association appeared to be similar in magnitude, but after careful adjustment for potential confounding with health status, the association weakened and was no longer statistically significant (HR = 1.17 per SD at age 50, 95% CI: 0.99-1.37). Perceived severity was not significantly associated with either extrinsic or intrinsic mortality even at age 50. Most Americans die at older ages, where stress exposure does not appear to be significantly associated with mortality. Nonetheless, our results suggest that stress exposure is more strongly associated with midlife mortality, which has an undue influence on overall life expectancy.

Racial Disparities in Cognitive Health Among Older Americans: The Role of Debt-Asset Profiles During Preretirement Age.

OBJECTIVES: Low-cost debt can potentially enhance wealth and indirectly benefit health, yet Black Americans disproportionately lack this type of debt, which may constrain their ability to accumulate wealth throughout their lives and across generations. Our objectives are to develop a novel debt-asset measure, use it to quantify the Black-White differential in debt-asset profiles, and estimate its contribution to the racial gap in cognition. METHODS: Using the Health and Retirement Study (1998-2020), we grouped individuals based on debt and asset information during the preretirement period of ages 55-61, including the absence of debt and the relative amount of debt compared to assets. Linear mixed models were used to examine the extent to which cognition in later life (ages 62-80) differs across these debt-asset profiles and its role in explaining the racial disparity in cognition. RESULTS: Compared with Whites, Blacks were more likely to fall into categories characterized by high debt-to-asset ratio (DAR) or limited asset ownership. Low-asset nonborrowers displayed the poorest cognition, followed closely by high-DAR borrowers. The Black-White differential in debt-asset profiles contributed to the racial gap in cognition. DISCUSSION: There were 2 unfavorable debt-asset profiles: high debt relative to assets and little or no debt due to a lack of assets, which was more prevalent among Blacks than Whites. We discuss how institutional and structural racism shapes Black-White disparities in debt-asset profiles, such as limited access to borrowing opportunities, thereby contributing to health inequalities, including cognition.

Economic distress, obesity, and the rise in pain.

Growing obesity may have contributed to widening socioeconomic disparities in pain in the US, but some researchers have suggested that deteriorating social and economic conditions among less advantaged Americans could be the root cause. We evaluated whether widening socioeconomic disparities in pain are associated with growing economic distress, particularly among those with low socioeconomic status (SES). We also assessed whether the link between economic distress and pain is mediated by obesity. Using data from nationally-representative samples targeting Americans aged 25-74 in 1995-96 (N = 3034) and 2011-14 (N = 2598), we fit a structural equation model to estimate the contributions of economic distress and obesity to period changes in the SES disparity in different types of pain. Socioeconomic disparities in backaches and joint pain widened substantially over recent decades, although there was no significant widening for headaches. Economic distress accounted for 34% of SES widening for backaches and 41% for joint pain, but the effect was largely independent of obesity. There was little evidence that economic distress led to obesity, which in turn fueled a rise in pain. Obesity alone explained another 8% of the widening SES disparity in backaches and 17% for joint pain. Economic distress played a larger role than obesity because economic distress increased over time for those with low SES whereas it decreased slightly for those with high SES. In contrast, obesity grew at all levels of SES, albeit more for those with low SES. Unfortunately, we cannot establish the direction of causation. Our model assumes that economic distress and obesity affect pain, but it is also possible that pain exacerbates obesity and/or economic distress. If SES disparities in pain continue to widen, it bodes poorly for the overall well-being of the US population, labor productivity, and the prospects for these cohorts as they reach older ages.

Exposure to childhood maltreatment predicts adult physiological dysregulation, particularly inflammation.

Although a growing literature describes the effects of negative childhood experiences on biological outcomes, it is difficult to compare results across studies because of differences in measures of childhood experiences, biological markers, sample characteristics, and included covariates. To ensure comparability across its analyses, this study used a single national survey of adults in the United States-the Midlife in the United States (MIDUS) study-to examine comprehensively the association between adverse childhood experiences, operationalized as childhood maltreatment (CM), and biological markers of risk for poor health and to assess whether these associations differ by type of maltreatment, sex, or race. The sample included 1254, mostly White (78%), adults aged 34-86 years (mean age 57 years), 57% of whom were female. We present incidence rate ratios (IRR) from negative binomial and Poisson regressions to examine the relationships between exposure to CM (emotional, physical, and sexual abuse; emotional and physical neglect; and a CM-index reflecting frequency across all five types of maltreatment) and four biological risk summary scores (overall physiological dysregulation, cardiometabolic risk, inflammation, and hypothalamic pituitary axis/sympathetic nervous system (HPA/SNS) function). We also tested whether the effect of each type of CM varied by sex and by race. The CM-index was associated with higher overall physiological dysregulation and inflammation, but the associations were weaker and not statistically significant for cardiometabolic risk and HPA/SNS function. With the exception of a possible sex difference in the association between sexual abuse and overall physiological dysregulation, there was little evidence that the associations varied systematically by type of CM or by sex or race. We conclude that exposure to CM predicts adult biological risk, particularly inflammation. Inconsistency with previous research suggests that additional research is needed to confirm findings regarding sex and race differences.

Smoking may compromise physical function long before it kills you.

Introduction: Although prior research has demonstrated an association between smoking and worse physical function, most of those studies are based on older people and do not evaluate whether the age-related increase in physical limitations differs by smoking history. We quantify how the magnitude of the smoking differential varies across age. Methods: This cohort study comprised a national sample of Americans aged 20-75 in 1995-1996, who were re-interviewed in 2004-2005 and 2013-2014. Our analysis was restricted to respondents who completed the self-administered questionnaires at Wave 1 (N = 6,325). Follow-up observations for those respondents were included if they completed the self-administered questionnaires at Wave 2 (N = 3,929) and/or Wave 3 (N = 2,849). The final analysis sample comprised 13,103 observations over a follow-up period of up to 19 years (1995-2014). We used a linear mixed model to regress physical limitations on smoking status at baseline adjusted for sex, age, race, socioeconomic status, alcohol abuse, drug abuse, and obesity with an interaction between age and smoking to test whether the age pattern of physical limitations differed by smoking history. Additional models incorporated measures of smoking duration and intensity. Results: In the fully-adjusted model, smokers exhibited a steeper age-related increase in physical limitations than never smokers. Thus, the disparities in physical limitations by smoking status widened with age but were evident even at young ages. The estimated differential between heavy smokers and never smokers rose from 0.24 SD at age 30 to 0.49 SD at age 80. At younger ages, heavy smokers who quit recently fared worse than current light smokers and not much better than current heavy smokers. Discussion: We know smoking is bad for our health, but these results reveal that differences in physical limitations by smoking history are evident even at ages as young as 30. Physical limitations that emerge early in life are likely to have an especially large impact because they can jeopardize health for decades of remaining life. Smoking probably will not kill you at young age, but it may compromise your physical function long before it kills you. Just do not do it.

Is the Pain killing you? Could Pain interference be a warning signal for midlife mortality?

Although prior studies have documented an association between various measures of pain and mortality, none of those studies has evaluated whether the association between pain and mortality varies significantly by age. We suspect that pain-particularly pain that interferes with the ability to lead a normal life-could be an early warning sign that may portend increased risk of physical impairment and mortality later in life. In this paper, we investigated whether pain was associated with increased mortality risk, particularly in midlife. Data came from the Midlife in the US study, which sampled non-institutionalized, English-speaking adults aged 25-74 in the contiguous United States in 1995-96. Our analysis included 4041 respondents who completed a follow-up self-administered questionnaire in 2004-05, 2703 of whom completed another self-administered questionnaire in 2013-14. We modeled mortality through December 31, 2021. In demographic-adjusted models, pain interference was more strongly associated with mortality than other pain measures, and the association was stronger at younger ages. The hazard ratio for pain interference declined from 1.39 per SD (95% CI 1.26-1.54) at age 60 to 1.14 (95% CI 1.04-1.24) at age 90. Although potential confounders accounted for more than 60% of the association with premature mortality, pain interference remained significantly associated with increased mortality rates (HR = 1.13 at age 60, 95% CI 1.02-1.26). We found no evidence that the association between pain and mortality was driven by cancer. If anything, pain interference was more strongly associated with cardiovascular than cancer mortality. At the oldest ages, physical function is likely to be a better predictor of mortality than pain. Yet, pain interference may be a useful warning sign at younger ages, when there are fewer physical limitations and mortality rates are low. It may be particularly helpful in identifying risk of premature mortality in midlife, before the emergence of severe physical limitations.

Cognition and Mortality Risk Among Midlife and Older Americans.

BACKGROUND: Cognitive impairment is associated with increased mortality rates in late life, but it is unclear whether worse cognition predicts working-age mortality. METHODS: The data come from a U.S. national survey (N = 3 973 aged 32-84 at cognitive testing in 2004-06, mean age 56.6, 56.3% female; N = 3 055 retested in 2013-18 at ages 42-94, mean age 64.6, 56.6% female; mortality follow-up through 2019). We use Cox hazard models to investigate whether cognition is associated with mortality below age 65, how the magnitude of this risk compares with the risk in later life, and whether the association persists after adjusting for potential confounders. RESULTS: Worse cognition is associated with mortality, but the demographic-adjusted hazard ratio (HR) diminishes with age from 2.0 per standard deviation (SD; 95% confidence interval [CI], 1.7-2.4) at age 55-1.4 (95% CI, 1.3-1.6) at age 85. In the fully adjusted model, the corresponding HRs are 1.4 (95% CI, 1.2-1.7) and 1.3 (95% CI, 1.1-1.4), respectively. The absolute differences in mortality by level of cognition, however, are larger at older ages because mortality is rare at younger ages. The fully adjusted model implies a 2.7 percentage point differential in the estimated percentage dying between ages 55 and 65 for those with low cognition (1 SD below the overall mean, 5.7%) versus high cognition (1 SD above the mean, 3.0%). The corresponding differential between ages 75 and 85 is 8.4 percentage points (24.6% vs 16.2%, respectively). CONCLUSIONS: Cognitive function may be a valuable early warning sign of premature mortality, even at working ages, when dementia is rare.

In the midst of a pandemic, more introverted individuals may have a mortality advantage.

Purpose: We investigated whether the relationship between extroversion and mortality changed during the COVID-19 pandemic. Methods: Midlife Americans were surveyed in 1995-96 with mortality follow-up through December 31, 2020. We used a Cox model to estimate age-specific mortality controlling for sex, race/ethnicity, the period trend in mortality, an indicator for the pandemic period (Mar-Dec 2020), extroversion, and an interaction between extroversion and the pandemic indicator. Results: Prior to the pandemic, extroversion was associated with somewhat lower mortality (HR = 0.93 per SD, 95% CI 0.88-0.97), but the relationship reversed during the pandemic. Extroversion was associated with greater pandemic-related excess mortality (HR = 1.29 per SD, 95% CI 1.002-1.67). That is, compared with persons who were more introverted, those who were highly extroverted suffered a bigger increase in mortality during the pandemic relative to pre-pandemic mortality levels. Conclusions: The slight mortality advantage enjoyed by more extroverted Americans prior to the pandemic disappeared during the first 10 months of the COVID-19 pandemic. We suspect that the mortality benefit of introversion during the pandemic is largely a result of reduced exposure to the risk of infection, but it may also derive in part from the ability of more introverted individuals to adapt more easily to reduced social interaction without engaging in self-destructive behavior (e.g., drug and alcohol abuse).

Income, wealth, and Black-White disparities in cognition.

We investigated the contributions of income and wealth (beyond education) to Black-White disparities in cognition and evaluated whether the role of socioeconomic status (SES) varies by age. Based on data from a national survey of Americans (aged 23-94), we used regression models to quantify the overall racial disparities in episodic memory, executive function, and overall cognition, adjusted for sex and age. Potential mediators (i.e., measures of childhood environment, educational attainment, marital status, occupation, income, and wealth) were added in subsequent models. The age- and sex-adjusted Black-White differential in overall cognitive function was around one standard deviation (SD) between ages 25 and 50, but declined to 0.6 SD by age 80. Executive function followed a similar pattern, but the racial disparity in episodic memory declined more rapidly between ages 35 (0.7 SD) and 80 (0.2 SD). Childhood environment and the respondent's educational attainment accounted for 20-25% of the racial disparities in overall cognition. The incremental contribution of household income was small (1-5%). Although wealth had only a small effect at younger ages, the contribution grew with age. Wealth was much more important than income in explaining Black-White disparities in cognition at older ages. Childhood environment, marital status, and SES (including wealth) accounted for one-third of the racial disparity in overall cognition at ages 35-65, but an even greater share at age 80. Our study is the first to demonstrate that, with increasing age, wealth explains more of the Black-White disparity in cognition. A widening racial gap in wealth and the disproportionate financial impact of the Great Recession and the COVID-19 pandemic on minorities do not bode well for Black-White differentials in cognition. Working-age Americans suffered the brunt of the economic impact of those events; the impact on cognition may increase as those cohorts grow older.

In the Midst of a Pandemic, Introverts May Have a Mortality Advantage.

Extroverts may enjoy lower mortality than introverts under normal circumstances, but the relationship may be different during an airborne pandemic when social contact can be deadly. We used data for midlife Americans surveyed in 1995-96 with mortality follow-up through December 31, 2020 to investigate whether the association between extroversion and mortality changed during the COVID-19 pandemic. We hypothesized that excess mortality during the pandemic will be greater for extroverts than for introverts. Results were based on a Cox model estimating age-specific mortality controlling for sex, race/ethnicity, the period trend in mortality, and an additional indicator for the pandemic period (Mar-Dec 2020). We interacted extroversion with the pandemic indicator to test whether the relationship differed between prepandemic and pandemic periods. Prior to the pandemic, extroversion was associated with somewhat lower mortality (HR=0.93 per SD, 95% CI 0.88-0.97), but the relationship reversed during the pandemic: extroverted individuals appeared to suffer higher mortality than their introverted counterparts, although the effect was not significant (HR=1.20 per SD, 95% CI 0.93-1.54). Extroversion was associated with greater pandemic-related excess mortality (HR=1.20/0.93=1.29 per SD, 95% CI 1.00-1.67). Compared with someone who scored at the mean level of extroversion, mortality rates prior to the pandemic were 10% lower for a person who was very extroverted (i.e., top 12% of the sample at Wave 1), while they were 12% higher for someone who was very introverted (i.e., 11 th percentile). In contrast, mortality rates during the pandemic appeared to be highe r for very extroverted individuals (HR=1.15, 95% CI 0.77-1.71) and l ower for those who were very introverted (HR=0.70, 95% CI 0.43-1.14) although the difference was not significant because of limited statistical power. In sum, the slight mortality advantage enjoyed by extroverts prior to the pandemic disappeared during the first 10 months of the COVID-19 pandemic. It remains to be seen whether that pattern continued into 2021-22. We suspect that the mortality benefit of introversion during the pandemic is largely a result of reduced exposure to the risk of infection, but it may also derive in part from the ability of introverts to adapt more easily to reduced social interaction without engaging in self-destructive behavior (e.g., drug and alcohol abuse). Introverts have been training for a pandemic their whole lives.

Assessment of Mortality Disparities by Wealth Relative to Other Measures of Socioeconomic Status Among US Adults.

Importance: The association between wealth and mortality is likely to be nonlinear and may result from selection and reverse causality. Objective: To compare the magnitude of mortality disparities by wealth relative to other measures of socioeconomic status (SES). Design, Setting, and Participants: This population-based cohort study began in 1995 to 1996, with approximately 18 years of mortality follow-up. These analyses were completed in November 2021. Data were derived from a population-based sample that targeted noninstitutionalized, English-speaking adults aged 25 to 74 years in the contiguous US. The response rate for the telephone interview ranged from 60% (twin subsample) to 70% (main sample). A self-administered questionnaire was completed by 89% of those interviewed by telephone. Exposures: Net assets of the respondent and spouse or partner in 1995 to 1996. Main Outcomes and Measures: All-cause mortality. Results: Among 6320 respondents (mean [SD] age at baseline, 46.9 [12.9] years; 3318 women [52.5%]), 1000 (15.8%) died by May 31, 2013. Adjusted for age, sex, and race, the mortality disparity by wealth was larger than the disparities by education, occupation, income, or childhood SES, especially at the oldest ages. After age 65 years, the hazard ratio [HR] was 2.69 (95% CI, 2.00-3.62) for those with no assets relative to those with at least $300 000 of wealth (in 1995 dollars), which translated into a 31 percentage point differential in estimated probability of surviving from age 65 years to 85 years (40% vs 71%). Additional wealth greater than $500 000 was not associated with lower mortality. In fully adjusted models, there was still a sizeable wealth disparity in mortality after age 65 years (HR, 1.89; 95% CI, 1.33-2.67). After adjustment for confounders, the estimated probability of surviving from age 65 to 85 years was 19 percentage points higher for persons with at least $300 000 in wealth (70%) than for those with no assets (51%), but there was a much larger 37 percentage point differential between never smokers (70%) and current smokers (33%). Conclusions and Relevance: In this cohort study, the fully adjusted disparity in mortality associated with wealth beyond age 65 years remained sizeable but was much smaller than the smoking differential.

The US Midlife Mortality Crisis Continues: Excess Cause-Specific Mortality During 2020.

Whether monthly excess mortality in the United States during 2020 varied by age and cause of death is investigated in this analysis. Based on national-level death counts and population estimates for 1999-2020, sex-specific negative binomial regression models were used to estimate monthly cause-specific excess mortality by age group during 2020. Among men, 71% non-COVID excess deaths occurred at working ages (25-64 years), but those ages accounted for only 36% of non-COVID excess deaths among women. Many excess deaths resulted from external causes (particularly among men), heart disease, diabetes, Alzheimer disease (particularly among women), and cerebrovascular disease. For men, the largest share of non-COVID excess deaths resulted from external causes, nearly 80% of which occurred at working ages. Although incorrectly classified COVID-19 deaths may explain some excess non-COVID mortality, misclassification is unlikely to explain the increase in external causes of death. Auxiliary analyses suggested that drug-related deaths may be driving the increase in external mortality, but drug overdoses were already increasing for a full year before the pandemic. The oldest Americans bore the brunt of COVID-19 deaths, but working-age Americans, particularly men, suffered substantial numbers of excess non-COVID deaths, most commonly from external causes and heart disease.

Widening Socioeconomic Disparities in Pain and Physical Function Among Americans Are Linked with Growing Obesity.

Objectives: We investigate whether obesity accounts for widening socioeconomic disparities in pain. Methods: Based on nationally representative samples of Americans aged 25-74 in 1995-1996 and 2011-2014, we use logistic regression to model period change in headaches, backaches, and joint aches as well as physical limitations and to determine whether those changes vary by a multidimensional measure of socioeconomic status. Results: Prevalence of backaches, joint aches, physical limitations, and obesity increased between the mid-1990s and the early 2010s, particularly among more disadvantaged Americans. Socioeconomic disparities in frequent backaches, frequent joint pain, and physical limitations more than doubled over this period. We estimate that obesity and health conditions may account for nearly a quarter of the widening disparity in frequent backaches and about half of the widening disparity in frequent joint pain and physical limitations. Discussion: Widening disparities in backaches, joint pain, and physical limitations have coincided with growing obesity.

Disadvantaged Americans are suffering the brunt of rising pain and physical limitations.

Using data from three national surveys of US adults (one cohort and two cross-sectional studies, covering the period from the mid-1990s to the mid-2010s), we quantify the degree to which disparities by socioeconomic status (SES) in self-reported pain and physical limitations widened and explore whether they widened more in midlife than in later life. Unlike most prior studies that use proxy measures of SES (e.g., education), we use a multidimensional measure of SES that enables us to evaluate changes over time in each outcome for fixed percentiles of the population, thereby avoiding the problem of lagged selection bias. Results across multiple datasets demonstrate that socioeconomic disparities in pain and physical limitations consistently widened since the late 1990s, and if anything, widened even more in midlife than in late life (above 75). For those aged 50-74, the SES disparities in most outcomes widened by more than 50% and in some cases, the SES gap more than doubled. In contrast, the magnitude of SES widening was much smaller above age 75 and, in the vast majority of cases, not significant. Pain prevalence increased at all levels of SES, but disadvantaged Americans suffered the largest increases. Physical function deteriorated for those with low SES, but there was little change and perhaps improvement among the most advantaged Americans. At the 10th percentile of SES, the predicted percentage with a physical limitation at age 50 increased by 6-10 points between the late-1990s and the 2010s, whereas at the 90th percentile of SES, there was no change in two surveys and in the third survey, the corresponding percentage declined from 31% in 1996-99 to 22% in 2016-18. The worst-off Americans are being left behind in a sea of pain and physical infirmity, which may have dire consequences for their quality of life and for society as a whole (e.g., lost productivity, public costs).

THE US MIDLIFE MORTALITY CRISIS CONTINUES: EXCESS CAUSE-SPECIFIC MORTALITY DURING 2020.

COVID-19 prematurely ended many lives, particularly among the oldest Americans, but the pandemic also had an indirect effect on health and non-COVID mortality among the working-age population, who suffered the brunt of the economic consequences. This analysis investigates whether monthly excess mortality in the US during 2020 varied by age and cause of death. Based on national-level death counts and population estimates for 1999-2020, negative binomial regression models-fit separately by sex-were used to estimate monthly cause-specific excess mortality by age group during 2020. Among males, 71% non-COVID excess deaths occurred at working ages (25-64), but those ages accounted for only 36% of non-COVID excess deaths in females. The results revealed substantial numbers of excess deaths from external causes (particularly among males), heart disease, diabetes, Alzheimer's disease (particularly among women), and cerebrovascular disease. For males, the largest share of non-COVID excess deaths resulted from external causes, nearly 80% of which occurred at working ages. Although incorrectly classified COVID-19 deaths may explain some excess non-COVID mortality, misclassification is unlikely to explain the increase in external causes of mortality. Auxiliary analyses suggested that drug-related mortality may be driving the rise in external mortality, but drug overdoses were already increasing for a full year prior to the pandemic. The oldest Americans bore the brunt of COVID-19 mortality, but working-age Americans, particularly men, suffered substantial numbers of excess non-COVID deaths, most commonly from external causes and heart disease.

Early-life education may help bolster declarative memory in old age, especially for women.

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.

Change in Mobility: Consistency of Estimates and Predictors Across Studies of Older Adults.

OBJECTIVES: This study compares estimates and determinants of within-individual changes in mobility across surveys of older U.S. adults. METHODS: Data come from the Health and Retirement Study (HRS) and the Midlife in the United States (MIDUS) study. Measures of mobility comprise self-reported level of difficulty with walking several blocks, going up several flights of stairs, lifting and carrying 10 pounds, and stooping. Predictors include sociodemographic characteristics and indicators of health and health behaviors. We pool the datasets and estimate weighted lagged dependent variable logistic regression models for each activity, assessing cross-study differences using interaction terms between a survey indicator and relevant variables. RESULTS: Estimates of declines in mobility differ substantially across surveys for walking, lifting and carrying, and stooping, but there are no between-survey differences in the probability of (not) recovering from a limitation. With the exception of age, determinants of change are similar between studies. For lifting/carrying and stooping, the age-related increase in developing limitations is less steep at younger ages for HRS respondents than MIDUS respondents, but steeper at older ages. DISCUSSION: To compare estimates of mobility change across surveys, mobility measures would need to be harmonized. Determinants of mobility change, however, are more comparable.

Loneliness, social isolation, and all-cause mortality in the United States.

Social isolation and loneliness are both established risk factors for mortality, but it remains unclear how these two conditions interact with each other. We used data from 3975 adults aged 25-74 years who completed self-administered questionnaires (SAQs) for the Midlife in the United States (MIDUS) National Study Wave 2 (2004-2006). Loneliness was measured by asking participants how often they felt lonely. A shortened version of the Berkman-Syme Social Network Index that captured partnerships, friends/family, religious participation, and other forms of social connection was used to assess social isolation. Follow-up for all-cause mortality was censored at the end of 2016. We used progressively adjusted Cox proportional hazard models to examine the mortality risks of loneliness, social isolation, the components of social isolation, and combinations of loneliness and isolation. We adjusted for sociodemographic characteristics in our first models and then added health behaviors and physical and mental health conditions in subsequent models. In the minimally adjusted model, loneliness was associated with higher mortality risk (HR, 1.34; 95% CI, 1.22-1.47), but the association was not significant in the fully adjusted model. Social isolation was significantly associated with mortality in the minimally adjusted model (HR, 1.24; 95% CI, 1.15-1.34) and the fully adjusted model (HR, 1.13; 95% CI, 1.04-1.23). Having infrequent contact with family or friends was the component of isolation that had the strongest association with mortality. Contrary to prior literature, which has found either no interaction or a synergistic interaction between isolation and loneliness, we identified a significant, negative interaction between the two measures, indicating that loneliness and social isolation may partially substitute for one another as risk factors for mortality. Both are associated with a similar increased risk of mortality relative to those who express neither; we find no evidence that the combined effect is worse than experiencing either by itself.

Socioeconomic disparities in U.S. mortality: The role of smoking and alcohol/drug abuse.

Prior studies have identified smoking as a key driver of socioeconomic disparities in U.S. mortality, but the growing drug epidemic leads us to question whether drug abuse is exacerbating those disparities, particularly for mortality from external causes. We use data from a national survey of midlife Americans to evaluate socioeconomic disparities in all-cause and cause-specific mortality over an 18-year period (1995-2013). Then, we use marginal structural modeling to quantify the indirect effects of smoking and alcohol/drug abuse in mediating those disparities. Our results demonstrate that alcohol/drug abuse makes little contribution to socioeconomic disparities in all-cause mortality, probably because the prevalence of substance abuse is low and socioeconomic differences in abuse are small, especially at older ages when most Americans die. Smoking prevalence is much higher than drug/alcohol abuse and socioeconomic differentials in smoking are large and have widened among younger cohorts. Not surprisingly, smoking accounts for the majority (62%) of the socioeconomic disparity in mortality from smoking-related diseases, but smoking also makes a substantial contribution to cardiovascular (38%) and all-cause mortality (34%). Based on the observed cohort patterns of smoking, we predict that smoking will further widen SES disparities in all-cause mortality until at least 2045 for men and even later for women. Although we cannot yet determine the mortality consequences of recent widening of the socioeconomic disparities in drug abuse, social inequalities in mortality are likely to grow even wider over the coming decades as the legacy of smoking and the recent drug epidemic take their toll.

Increases in BMI and chronic pain for US adults in midlife, 1992 to 2016.

Recent unprecedented increases in mortality and morbidity during midlife are often ascribed to rising despair in the US population. An alternative and less often examined explanation is that these trends reflect, at least in part, the lagged effects of the obesity epidemic. Adults in midlife today are more likely to live with obesity and have a greater cumulative exposure to excess adiposity during their lifetime than any previous generation. Prior work has demonstrated a link between obesity and mortality risk at midlife, but the mechanisms remain unclear. Pain may represent one important pathway linking obesity to mortality trends. Pain is a debilitating condition that has increased significantly over recent decades and is associated with both morbidity and mortality, including suicide and opioid-related mortality. Evidence suggests obesity and pain may be linked, but there is little evidence of an association at the population level. In this paper, we examine to what extent increases in overweight and obesity explain the rising trends in chronic pain observed among middle-aged adults in the US from 1992 to 2016. We assess trends in both mild/moderate nonlimiting pain and severe and/or limiting pain. In doing so, we draw attention to one mechanism through which overweight/obesity may have contributed to recent population health trends. Our analysis found that increases in BMI from 1992 to 2016 may account for up to 20% of the upward trend in mild/moderate nonlimiting pain and 32% of the trend in severe and/or limiting pain for women, and 10% and 19% of the trends respectively for men.