Established Populations For Epidemiologic Studies Research Articles

Characteristics of Mexican American Elders Admitted to Nursing Facilities in the United States: Data from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (EPESE) Study

The purpose of the current study was to describe the factors associated with Mexican American elders in the Southwestern United States who have spent time in a skilled nursing facility (SNF) compared with those who have not. Data were collected on the Mexican American elders who reported an SNF stay within 10 years of baseline. A probability sample of 3050 Mexican American elders from five Southwestern states followed from 1993 to 2005 were examined. Variables examined included sociodemographics, language of interview, disabilities with instrumental activities of daily living, activities of daily living, self-reported health, cognitive status, and depression. A total of 78 (3.9%) of 2020 subjects resided in SNFs. Using univariate analyses, older age, English-language interview, poorer cognitive status, and functional disabilities were independently associated with SNF admissions. Logistic regression analyses controlling for age revealed that SNF patients were older (OR= 1.08, P= .001), had an activities of daily living disability (OR= 4.94, P < .001), scored in the depressed range in the Geriatric Depression Scale (OR= 2.72, P= .001), and were more likely to interview in English (OR=1.95, P= .042), when compared with community counterparts. Mexican American elders who resided in an SNF at some point in the previous 10 years were older, and were more likely to be functionally impaired. They also were more likely to prefer English as their primary language, indicating they were more likely to agree to an SNF stay than their Spanish-speaking counterparts.

Semiparametric Analysis of Longitudinal Zero-inflated Count Dat a with Applications to Instrumental Activities of Daily Living

Background: The instrumental activities of daily living (IADLs) are important index of physical functioning in older adult studies. These count outcomes with a large proportion of zeros are often collected in longitudinal studies. Data were from the Hispanic Established Population for Epidemiological Study of the Elderly (HEPESE), a four wave (seven years) longitudinal study of community-dwelling elderly Mexican-Americans. There were excess zeros IADLs observed during follow-up. Methods: We present semiparametric zero-inflated Poisson (ZIP) and hurdle model with random effects to evaluate IADLs in the context of excess zeros. Results: Age, education, household income, marital status, smoking, cognitive functioning and prescription medication use were not significantly associated with IADLs. The counts of IADLs changed with age nonlinearly. Conclusions: zero-inflated Poisson (ZIP) and hurdle model with random effect fits the IADLs counts with excess zeros in longitudinal studies.

Pregnancy as a risk factor for ambulatory limitation in later life.

We investigated the relationship between the number of times a woman has been pregnant and walking difficulty in later life. With data from the Hispanic Established Populations for Epidemiologic Studies of the Elderly, a representative population-based cohort of Mexican Americans aged 65 years and older residing in 5 Southwestern states, we measured walking difficulty using 2 items from the performance-oriented mobility assessments: the timed walk and seated chair rise. We observed significantly higher rates of ambulatory limitation among women with 6 or more pregnancies than among women with 4 or fewer pregnancies: 44.9% and 27.0%, respectively, were unable to perform or performed poorly in the seated chair rise and timed walk. Ordinal logistic regression models show that gravidity predicts level of performance in both mobility tasks and that higher gravidity is associated with worse performance, even after adjustment for both age and chronic disease. Gravidity is a risk factor for ambulatory limitation in old age. A life course approach to reproduction in public health research and practice is warranted.

The role of physical activity and diabetes status as a moderator: functional disability among older Mexican Americans

we investigate the temporal association between the rate of change in physical function and the rate of change in disability across four comparison groups: Those with and without diabetes who report >30 min of physical activity per day, and those who report <30 min of physical activity per day. six waves of longitudinal data from the Hispanic Established Population for Epidemiologic Studies of the Elderly were utilised. At baseline, there were a total of 3,050 elder participants aged 65 years old or greater. The longitudinal rates of change in disability and physical function were compared by the diabetes status (ever versus none) and the physical activity status (less than or greater than or equal to 30 min per day). disability and physical function data were analysed using a latent growth curve modelling approach adjusted for relevant demographic/health-related covariates. There were statistically significant longitudinal declines in physical function and disability (P < 0.001) in all groups. Most notable, the physical activity status was an important moderator. Those with >30 min of activity demonstrated better baseline function and less disability as well as better temporal trajectories than those reporting <30 min of physical activity per day. Comparisons between diabetes statuses within the same physical activity groups showed worse disability trajectories among those with diabetes. a longitudinal decline in physical function and disability is moderated most notably by physical activity. The diabetes status further moderates decline in function and disability over time. Increased physical activity appears to be protective of disability in general and may lessen the influence of diabetes-related disability in older Mexican Americans, particularly at the end of life.

Is cancer incidence decreased in the frail elderly? Evidence from a prospective cohort study

Lower rates of cancer in the oldest old and in nursing home populations may reflect the increasing prevalence of frailty and a diminished capacity to sustain cancer cell growth and proliferation. This study aimed to determine cancer incidence in the frail relative to non-frail community resident older adults. Data from 3969 participants free of diagnosed cancer at the sixth follow-up from three sites of the Established Populations for Epidemiologic Studies of the Elderly (EPESE), a population-based cohort study. Frailty status was determined from physical performance testing and self reported dependency in activities of daily living. Cancer incidence over the four subsequent years was identified through linkage with Medicare claims data. Logistic regression was used to estimate the odds of cancer incidence with respect to frailty status in multiple models with progressive adjustment for covariates. Of the 3969 participants, 1340 (33.8%) were identified as frail. Cancer incidence at 4years was lower in frail participants overall (OR 0.64; 95% CI 0.46-0.89) and frail men in particular (OR 0.54; 95% CI 0.33-0.87). Incidence was lower in women (3.7%) than in men (8.8%), but was not lower in frail women compared with non-frail women (OR 0.77; 95% CI 0.48-1.23). Frailty status was associated with decreased cancer incidence, particularly in men, and suggests that mechanisms related to the pathogenesis of frailty may also play a role in inhibiting tumorigenesis. Why this would be more apparent in men than women remains to be clarified.

Socioeconomic status and the Black-White mortality crossover.

We investigated associations among age, race, socioeconomic status (SES), and mortality in older persons and whether low SES contributes to the Black-White mortality crossover (when elevated age-specific mortality rates invert). We used panel data from the North Carolina Established Populations for Epidemiologic Studies of the Elderly to test the main and interactive effects of SES on mortality. Discrete-time hazard models showed that the association between low education and mortality did not vary by race or age and was only significant for men. For women, the effect of low income diminished with age and had little impact on the crossover. For men, low income varied by race and age, altering the Black-White crossover and producing low-high income crossovers at advanced ages. Low education and income were associated with increased mortality risk for older adults, but only low income had a differential impact on the Black-White mortality crossover. A primary route to reducing mortality differentials in later life is to prevent the disproportionate selective mortality of Blacks and the poor earlier in the life course.

Higher Medical Morbidity Burden Is Associated with External Locus of Control

To describe the association between an increasing number of coexisting conditions and locus of control (LOC), a psychological construct reflecting the degree to which one perceives circumstances to be controlled by personal actions (internal LOC) versus outside factors (external LOC) in older adults. Cross-sectional study using survey data from the North Carolina Established Population for Epidemiologic Studies of the Elderly (NC EPESE) data set. Community. Three thousand two hundred twelve community-dwelling adults aged 68 and older. Nine common medical conditions were assessed according to self-report. LOC was measured using a standard questionnaire. Analyses were adjusted for demographics, functional status (self-reported activities of daily living), cognition (Short Portable Mental Status Questionnaire), and depression score (Center for Epidemiologic Studies Depression Scale). A higher number of chronic conditions was associated with external LOC (β = 0.37, P < .001). This relationship persisted after adjustment for age, race, sex, functional status, cognition, and depression (β = 0.17, P < .001). Most individual conditions were not associated with LOC, although vision impairment (P < .001) and arthritis (P = .02) were associated with more-internal LOC. These results suggest that medically complex patients tend to exhibit a more-external LOC, meaning that they perceive little personal control over circumstances and environment. Clinicians should be aware of this tendency, because external LOC may impede an older adult's willingness to engage in the considerable task of managing multiple chronic conditions.

Trajectory classes of depressive symptoms in a community sample of older adults.

To identify trajectories of depressive symptoms in older community residents. Depressive symptomatology, based on a modified Center for Epidemiological Studies-Depression scale, was obtained at years 0, 3, 6, and 10, in the Duke Established Populations for Epidemiologic Studies of the Elderly (n = 4162). Generalized growth mixture models identified the latent class trajectories present. Baseline demographic, health, and social characteristics distinguishing the classes were identified using multinomial logistic regression. Four latent class trajectories were identified. Class 1 - stable low depressive symptomatology (76.6% of the sample); class 2 - initially low depressive symptomatology, increasing to the subsyndromal level (10.0%); class 3 - stable high depressive symptomatology (5.4%); class 4 - high depressive symptomatology improving over 6 years before reverting somewhat (8.0%). Class 1 was younger, male gender, with better education, health, and social resources, in contrast to class 3. Class 2 had poorer cognitive functioning and higher death rate. Class 4 had better health and social resources. Reduction in high depressive symptomatology is associated with more education, better health, fewer stressful events, and a larger social network. Increasing depressive symptomatology is accompanied by poorer physical and cognitive health, more stressful life events, and greater risk of death.

Body mass index and mortality rate among Hispanic adults: a pooled analysis of multiple epidemiologic data sets

To evaluate the association between body mass index (BMI, kg m⁻²) and mortality rate among Hispanic adults. Analysis of five data sets (total N=16,798) identified after searching for publicly available, prospective cohort data sets containing relevant information for at least 500 Hispanic respondents (≥18 years at baseline), at least 5 years of mortality follow-up, and measured height and weight. Data sets included the third National Health and Nutrition Examination Survey, the Puerto Rico Heart Health Program (PRHHP), the Hispanic Established Population for Epidemiologic Studies of the Elderly (HEPESE), the San Antonio Heart Study (SAHS) and the Sacramento Area Latino Study on Aging. Cox proportional hazards regression models, adjusting for sex and smoking, were fit within three attained-age strata (18 to younger than 60 years, 60 to younger than 70 years, and 70 years and older). We found that underweight was associated with elevated mortality rate for all age groups in the PRHHP (hazard ratios [HRs]=1.38-1.60) and the SAHS (HRs=1.88-2.51). Overweight (HRs=0.38 and 0.84) and obesity grade 2-3 (HRs=0.75 and 0.60) associated with reduced mortality rate in the HEPESE dataset for those in the 60 to younger than 70 years, and 70 years and older attained-age strata. Weighted estimates combining the HRs across the data sets revealed a similar pattern. Among Hispanic adults, there was no clear evidence that overweight and obesity associate with elevated mortality rate.

The Protective Effect of Neighborhood Composition on Increasing Frailty Among Older Mexican Americans

Little is known about the nature of the frailty syndrome in older Hispanics who are projected to be the largest minority older population by 2050. The authors examine prospectively the relationship between medical, psychosocial, and neighborhood factors and increasing frailty in a community-dwelling sample of Mexican Americans older than 75 years. Based on a modified version of the Cardiovascular Health Study Frailty Index, the authors examine 2-year follow-up data from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-EPESE) to ascertain the rates and determinants of increasing frailty among 2,069 Mexican American adults 75+ years of age at baseline. Respondents at risk of increasing frailty live in a less ethnically dense Mexican-American neighborhood, are older, do not have private insurance or Medicare, have higher levels of medical conditions, have lower levels of cognitive functioning, and report less positive affect. Personal as well as neighborhood characteristics confer protective effects on individual health in this representative, well-characterized sample of older Mexican Americans. Potential mechanisms that may be implicated in the protective effect of ethnically homogenous communities are discussed.

The Coronary Artery Disease–Associated 9p21 Variant and Later Life 20-Year Survival to Cohort Extinction

Common variation at chromosome 9p21 (marked by rs10757278 or rs1333049) is associated with coronary artery disease (CAD) and peripheral vascular disease. A decreasing effect at older age was suggested, and effects on long-term mortality are unclear. We estimated 9p21 associations with CAD and all-cause mortality in a CAD diagnosis-free older population. We also estimated classification gains on adding the variant to the Framingham Risk Score (FRS) for CAD. DNA was from an Established Populations for Epidemiological Study of the Elderly-Iowa cohort from 1988 (participants >71 years), with death certificates obtained to 2008 for 92% of participants. Cox regression models were adjusted for confounders and CAD risk factors. Of 1095 CAD diagnosis-free participants, 52% were heterozygous (CG) and 22% were homozygous (CC) for the risk C allele rs1333049. Unadjusted CAD-attributed death rates in the CC group were 30 vs 22 per 1000 person-years for the GG group. The C allele was associated with all-cause (hazard ratio, 1.19; 95% CI, 1.08-1.30) and CAD (hazard ratio, 1.29; 95% CI, 1.08-1.56) mortality, independent of CAD risk factors. There was no association with stroke deaths. Variant associations with CAD mortality were attenuated after the age of 80 years (age-interaction term P=0.05). In age group 71 to 80 years, FRS classified as high risk 21% of respondents who died of CAD within 10 years; adding 9p21 identified 27% of respondents. In 71- to 80-year-old subjects free of CAD diagnoses, 9p21 is associated with excess mortality, mainly attributed to CAD mortality. Adding 9p21 to the FRS may improve the targeting of CAD prevention in older people, but validation in independent samples is needed for confirmation.

Relations of a Marker of Endothelial Activation (s-VCAM) to Function and Mortality in Community-Dwelling Older Adults

We wished to determine if a marker of endothelial dysfunction/activation soluble vascular cell adhesion molecule (s-VCAM)-was related to functional status and mortality in community-dwelling older adults independent of the known effects of markers of inflammation and coagulation. Data came from the third and fourth in-person waves of the Duke Established Populations for Epidemiologic Studies of the Elderly. Participants (aged ≥ 71 years) had participated in a blood draw (N = 1,551) from which concentrations of s-VCAM, interleukin-6, and D-dimer were determined. Information was gathered in-person on demographics, health behaviors, chronic health conditions, and functional status (Katz, Rosow-Breslau, Nagi). Death was determined through the National Death Index. Multivariable regression analysis was used to examine the adjusted association of s-VCAM with functional status; Cox proportional hazards models ascertained hazard of mortality. Controlled analyses indicated that cross-sectionally, but not longitudinally (4 years later), greater s-VCAM concentrations were associated with poorer function as measured by the Katz and Rosow-Breslau scales (p < .05 for both), independent of interleukin-6 and D-dimer. In controlled analyses, s-VCAM (p = .002), D-dimer (p = .008), and interleukin-6 (p = .01) were independently related to 4-year mortality; 1 SD increase in log concentration conferred 1.2-, 1.1-, and 1.2-fold increases in mortality, respectively. The greatest hazard of mortality was observed within the first year after measurement. s-VCAM concentrations were not predictive of 15-year mortality. Independent of inflammation and coagulation markers, endothelial dysfunction serves as a marker of, and potentially contributes causally to, poor function and death in community-dwelling older adults.

Predictors of Extraordinary Survival in the Iowa Established Populations for Epidemiologic Study of the Elderly: Cohort Follow-Up to “Extinction”

To identify predictors of extraordinary survival. Longitudinal study of a cohort of elderly people followed up until almost all have died. Two counties in Iowa; a part of the Established Populations for Epidemiologic Study of the Elderly. Two thousand eight hundred ninety community-dwelling citizens aged 65 to 85 at baseline and surviving at least 3 years. Data relating to age, sex, birth order, parental longevity, marital status, education, family income, social support, self-reported health, chronic diseases, blood pressure, body mass index, physical ability, exercise, life attitude and mental health were obtained. Extraordinary survivors (ESs) were defined to include approximately 10% of the longest survivors in their sex group. The 253 ESs were far more likely never to have smoked. In models adjusted for age, sex, and smoking, the earlier-life factors such as parental longevity, being earlier in the birth order (in women only), and body mass index at age 50 were associated with extraordinary survival. In similar models for predictors at age 65 to 85, extraordinary survival was associated with excellent self-reported health, fewer chronic diseases, better physical mobility and memory, and positive attitude toward life, but it was not associated with depression, anxiety, or sleep quality. In multivariable models, attitude toward life was not an independent predictor. Women in the top third of a cumulative score of independent predictors were 9.3 (95% confidence interval=4.4-19.6, P<.001) times as likely to reach extraordinary survival as those in the bottom third. ESs had fewer "classical" risk factors and were in better health than their contemporaneous controls. Possibly genetic factors such as parental longevity and birth order appear to be less predictive in men than in women.

Black-white disparity in disability: the role of medical conditions.

To describe the independent contributions of selected medical conditions to the disparity between black and white people in disability rates, controlling for demographic and socioeconomic factors. Cross-sectional analysis of a community-based cohort. Urban and rural counties of central North Carolina. Two thousand nine hundred sixty-six adults aged 68 and older participating in the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE). Self-reported data on sociodemographic characteristics and medical conditions, Short Portable Mental Status Questionnaire, activities of daily living (ADLs). Fifty-five percent of the cohort was black. Blacks were more likely than whites to report disability (odds ratio=1.39, 95% confidence interval= 1.15-1.68). Controlling for age, sex, marital status, and socioeconomic status, blacks were more likely to be obese and have diabetes mellitus, and less likely to report vision problems, fractures, and heart attacks. The higher prevalence of obesity and diabetes mellitus in blacks, after adjustment for sociodemographic factors, accounted for more than 30% of the black-white difference in disability. Conversely, the black-white disability gap would be approximately 45% wider if whites had a lower prevalence of fractures and vision impairment, similar to their black peers. Higher rates of obesity and diabetes mellitus in older black Americans account for a large amount of the racial disparity in disability, even after controlling for socioeconomic differences. Culturally appropriate interventions that lower the prevalence or the functional consequences of obesity and diabetes mellitus in blacks could substantially decrease this racial health disparity.

Predicting Glaucoma Diagnosis in an Elderly Sample: Revisiting the Established Populations for Epidemiologic Studies of the Elderly

Though research has examined race as an important factor in defining the scope of glaucoma in the United States, further exploration into other specific factors may help inform the design of preventive services to decrease rates of blindness due to glaucoma among minority groups. This study examined glaucoma diagnosis among a sample of elderly patients from the North Carolina Established Populations for the Epidemiologic Studies of the Elderly. Caucasians without diabetes are more likely to have a glaucoma diagnosis. In contrast, having diabetes was a marginally significant predictor of a glaucoma diagnosis among African American study participants. Identifying individual-level characteristics and different service-level issues that underlie specific ethnic groups may help to develop more precisely targeted interventions to improve a full range of health care services for elderly patients.

The Causal Pathway From Socioeconomic Status to Disability Trajectories in Later Life: The Importance of Mediating Mechanisms for Onset and Accumulation

This study examines the mechanisms by which different aspects of socioeconomic status affect disability trajectories among older adults. The author conceptualizes and models disability in two life course components, onset and growth, in order to see how socioeconomic status and its mechanisms differ in their effects on the timing and accumulation of disablement. Using the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE), the author finds that the effects of education are mainly preventive for disability onset where financial resources both delay and ameliorate a trajectory of disability accumulation after onset. Health behaviors and mastery work as independent mediators of education while financial-based capital works to mediate both income and education effects. This study highlights transitions and trajectories in health processes, showing that education effects are far reaching and robust but only work for onset, while financial-based capital is effective in ameliorating a trajectory of disability in later life.

Frailty, Mortality, and Health‐Related Quality of Life in Older Mexican Americans

To determine the effect of health-related quality of life (HRQOL) on the relationship between frailty status and survival in older Mexican-American adults. Prospective analysis of participants in the Hispanic Established Populations for Epidemiologic Study of the Elderly. Urban and rural areas of five southwestern states: Arizona, California, Colorado, New Mexico, and Texas. One thousand eight Mexican-American adults aged 74 to 101 interviewed between 2005 and 2006. Trained interviewers collected information on patient demographics, health conditions, frailty status, HRQOL, and survival. Frailty was associated with a greater odds of death (odds ratio = 2.72, 95% confidence interval = 1.5-5.1) over a period of 2 to 3 years. After adjusting for the physical component of HRQOL, being frail (as opposed to prefrail or nonfrail) was no longer significantly associated with mortality. The mental health component of HRQOL did not affect the relationship between frailty and mortality. Older Mexican Americans identified as frail experienced poorer survival in this sample than their prefrail or nonfrail counterparts. Adjusting for the physical component of HRQOL attenuated poorer survival in persons categorized as frail.

Acculturation and Depressive Symptoms Among Mexican American Elders New to the Caregiving Role: Results From the Hispanic-EPESE

The purpose of this study was to identify characteristics associated with becoming a caregiver among Mexican American (MA) elders and to examine predictors of depressive symptoms among the new caregivers 2 years later. Drawn from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-EPESE), 152 MA recent caregivers and 2,023 other MAs were compared. Residualized change regression analysis was conducted. At baseline, MAs who had recently become caregivers exhibited a significantly greater number of depressive symptoms compared to those who had not. Controlling for background characteristics, physical health, social support, and baseline depressive symptoms, regression analysis revealed that 2 years later higher acculturation was related to a greater number of depressive symptoms among those who at baseline were new caregivers. Better knowledge of the within-group differences among MA elderly caregivers, especially with respect to acculturation, may better inform interventions for this at-risk group.

Shorter Stay, Longer Life: Age at Migration and Mortality Among the Older Mexican-Origin Population

In this article, we investigate the association between age at migration and mortality during a 13-year period in a sample of Mexican American immigrants 65 and older at baseline. We employ the Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-PESE) to control for mortality-related health and social factors. Our analyses show that the immigrant generation does not represent a homogeneous mortality risk category. Individuals who migrated to the United States in mature adulthood have a considerably lower risk of death than individuals who migrated in childhood or midlife. Chronic conditions or functional capacity do not account for these differences. Our findings suggest that standard risk pools may differ significantly on the basis of genetic and unmeasured life-course factors. A better understanding of the late-life immigrant mortality advantage has important implications for more effective and targeted social and medical interventions.

The Relationship Between Education Level and Mini-Mental State Examination Domains Among Older Mexican Americans

To study the effect of education and language of response at the interview on performance in the Mini-Mental State Examination (MMSE) domains, we studied 2861 Mexican Americans aged 65 and older from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (EPESE) followed from 1993 to 1994 until 2004 to 2005. The MMSE was examined as total score (0-30) or divided into 2 global domains: (1) no-memory (score 0-24): Orientation, attention, and language; and (2) memory (score 0-6): working and delayed memory. Mean age and total MMSE were 72.7 years and 24.6 at baseline, and 81.7 years and 20.5 at 11 years of follow-up. Spanish-speaking participants had less education (4.1 vs 7.4 years, P < .0001), they had significantly higher adjusted mean scores for memory, no-memory, and total MMSE compared with English-speaking participants. In multivariate longitudinal analyses, participants with more years of education performed better than those with less education, especially in total MMSE and no-memory domain. Spanish-speaking participants with 4 to 6 years of education had higher memory scores than those speaking English (estimate 0.40, standard error [SE] = 0.14, P < .001), 7 to 11 (estimate 0.27, standard error = 0.13, P < .01) or 12+ (estimate 0.44, standard error = 0.13, P < .001). Results suggest that cultural factors and variables related to preferred language use determined variations in MMSE performance. Because the memory domain of the MMSE is less affected by education, it may be used along with other cognitive tests for early detection of cognitive decline in older populations with low education.