Gender, Personality, and Cognitive Resilience Against Early-Life Disadvantage.

OBJECTIVES: Early-life disadvantage (ELD) relates to lower late-life cognition. However, personality factors, including having an internal locus of control (LOC) or a conscientious personality, relate to resilience and effective stress coping. We explore whether personality factors convey resilience against the negative effects of ELD on cognition, by gender, in Mexico. METHODS: Using the 2015 Mexican Health and Aging Study, we estimated expected cognition using multiple ELD markers to identify a subsample in the lowest quartile of expected cognition given ELD (n = 2,086). In this subsample, we estimated cross-sectional associations between personality and having above-median observed cognitive ability (n = 522) using logistic regression. RESULTS: Among those in the lowest quartile of expected cognition, a more internal LOC (ß = 0.32 [men] and ß = 0.44 [women]) and conscientious personality (ß = 0.39 [men] and ß = 0.17 [women]) were significantly associated with having above-median cognitive ability in models adjusted for demographic confounders. Larger benefits of conscientiousness were observed for men than women. Associations between personality and having above-median cognitive ability remained statistically significant after further adjustment for health, stress, and cognitive stimulation variables, regardless of gender. DISCUSSION: Personality factors may convey resilience among individuals who experienced ELD, potentially breaking the link between ELD and worse late-life cognition. Structural factors and gender roles may affect how much women benefit from personality factors.

The Relationship Between Multimorbidity and Types of Chronic Diseases and Self-Rated Memory.

This study explores the impact of multimorbidity and types of chronic diseases on self-rated memory in older adults in the United States. Data were drawn from the 2011 wave of the National Health and Aging Trends Study (NHATS, N = 6,481). Logistic regressions were used to examine the associations between multimorbidity and types of chronic diseases and fair/poor self-rated memory. Compared to respondents with no or one chronic disease, respondents with multimorbidity showed 35% higher odds of reporting fair/poor self-rated memory. Also, stroke, osteoporosis, and arthritis were identified as increasing the odds of reporting fair/poor self-rated memory by 41%, 20%, and 30%, respectively. Demonstrating the importance of both multimorbidity and types of chronic diseases in self-reporting of memory, our findings suggest the need to educate older adults with multimorbidity and certain types of diseases regarding negative self-rated memory and its consequences.

Food Insecurity across the Life-Course and Cognitive Function among Older Mexican Adults.

BACKGROUND: Food insecurity remains a global public health problem. Experiencing food insecurity is related to poorer cognitive function among older adults. However, few studies have examined how food insecurity, experienced over the life-course, relates to cognitive function among older adults in Mexico. METHODS: Data came from the 2015 Mexican Health and Aging Study (n = 11,507 adults aged 50 and over). Early- and late-life food insecurity were ascertained by self-report. We evaluated how both measures of food insecurity related to the performance of multiple cognitive tasks (Verbal Learning, Verbal Recall, Visual Scanning, and Verbal Fluency), while controlling for key health and sociodemographic confounders using linear regression. RESULTS: In descriptive analyses, respondents who experienced food insecurity in either early or late life performed significantly worse on all cognitive tasks when compared to the food secure. In models adjusted for health and sociodemographic confounders, early-life food insecurity predicted worse Verbal Learning performance and late-life food insecurity was associated with poorer Visual Scanning performance. CONCLUSIONS: Food insecurity was related to poorer cognitive function in a nationally representative sample of older adults in Mexico. However, results suggested that the significance of effects depended on cognitive task and when in the life-course food insecurity was experienced.

Rural/urban dwelling across the life-course and late-life cognitive ability in Mexico.

BACKGROUND: Urban advantages in older adults' cognitive function have been observed. Less is known about early-life urban dwelling and late-life cognition. We evaluate how rural/urban dwelling throughout life and rural to urban shifts in life relate with cognition in Mexico, a country experiencing aging and urbanization. METHODS: Data came from the 2003 and 2012 Mexican Health and Aging Study (n = 12,238 adults age 50+). Early-life urban dwelling was self-reported. Late-life urban dwelling was based on population size of respondents' community of residence (community 2500+ people) at the time of survey. Cognitive function was measured across several cognitive tasks. We assess differences in baseline cognitive function and nine-year decline across groups using a latent change score model. RESULTS: Cross-sectionally, compared to always rural dwellers, rural-urban transitions were associated with cognitive benefits, though individuals residing in urban areas continuously through life exhibited the highest levels of cognitive function (ß = 0.89, 95% CI: 0.83, 0.96) even after adjusting for SES, health, and health behaviors (ß = 0.28, 95% CI: 0.22, 0.35). Longitudinally, always urban dwellers exhibited slower decline than always rural dwellers when adjusting for baseline cognition (ß = 0.11, 95% CI: 0.03, 0.18), though faster decline when baseline cognition was not adjusted (ß = -0.11, 95% CI: -0.18, -0.04). No differences were observed for cognitive change across comparison groups after adjusting for potential mechanisms. CONCLUSIONS: Early- and late-life urban dwelling may result in cognitive advantages for older Mexican adults. Clinicians should consider where individuals resided throughout life to better understand a patient's likelihood of experiencing poor cognitive outcomes.

Effect of Demographic and Health Dynamics on Cognitive Status in Mexico between 2001 and 2015: Evidence from the Mexican Health and Aging Study.

Sources of health disparities such as educational attainment, cardiovascular risk factors, and access to health care affect cognitive impairment among older adults. To examine the extent to which these counteracting changes affect cognitive aging over time among Mexican older adults, we examine how sociodemographic factors, cardiovascular diseases, and their treatment relate to changes in cognitive function of Mexican adults aged 60 and older between 2001 and 2015. Self and proxy respondents were classified as dementia, cognitive impairment no dementia (CIND), and normal cognition. We use logistic regression models to examine the trends in dementia and CIND for men and women aged 60 years or older using pooled national samples of 6822 individuals in 2001 and 10,219 in 2015, and sociodemographic and health variables as covariates. We found higher likelihood of dementia and a lower risk of CIND in 2015 compared to 2001. These results remain after adjusting for sociodemographic factors, cardiovascular diseases, and their treatment. The improvements in educational attainment, treatment of diabetes and hypertension, and better access to health care in 2015 compared to 2001 may not have been enough to counteract the combined effects of aging, rural residence disadvantage, and higher risks of cardiovascular disease among older Mexican adults.

Household use of polluting cooking fuels and late-life cognitive function: A harmonized analysis of India, Mexico, and China.

INTRODUCTION: Exposure to high levels of air pollution is associated with poor health, including worse cognitive function. Whereas many studies of cognition have assessed outdoor air pollution, we evaluate how exposure to air pollution from combustion of polluting household fuels relates with cognitive function using harmonized data from India, Mexico, and China. MATERIALS & METHODS: We analyze adults age 50+ in three nationally representative studies of aging with common data collection methods: the 2017-2019 Longitudinal Aging Study in India (n = 50,532), 2015 Mexican Health and Aging Study (n = 12,883), and 2013 China Health and Retirement Longitudinal Study (n = 12,913). Use of polluting fuels was assessed by self-report of wood, coal, kerosene, crop residue, or dung for cooking. Cognitive function was measured by performance across several cognitive domains and summarized into a total cognition score. We used linear regression, by country, to test how polluting cooking fuel use relates with cognition adjusting for key demographic and socioeconomic factors. RESULTS: Approximately 47%, 12%, and 48% of respondents in India, Mexico, and China, respectively, relied primarily on polluting cooking fuel, which was more common in rural areas. Using polluting cooking fuels was consistently associated with poorer cognitive function in all countries, independent of demographic and socioeconomic characteristics. Adjusted differences in cognitive function between individuals using polluting and clean cooking fuel were equivalent to differences observed between individuals who were 3 years of age apart in Mexico and China and 6 years of age apart in India. Across countries, associations between polluting cooking fuel use and poorer cognition were larger for women. CONCLUSIONS: Results suggest that household air pollution from the use of polluting cooking fuel may play an important role in shaping cognitive outcomes of older adults in countries where reliance on polluting fuels for domestic energy needs still prevails. As these countries continue to age, public health efforts should seek to reduce reliance on these fuels.

Solid cooking fuel use and cognitive decline among older Mexican adults.

Studies of air pollution and cognition often rely on measures from outdoor environments. Many individuals in low- and middle-income countries are exposed to indoor air pollution from combustion of solid cooking fuels. Little is known about how solid cooking fuel use affects cognitive decline over time. This study uses data from the 2012, 2015, and 2018 Mexican Health and Aging Study (n = 14 245, age 50+) to assess how use of wood or coal for cooking fuel affects cognition of older adults relative to use of gas. It uses latent change score modeling to determine how using solid cooking fuel affected performance in Verbal Learning, Verbal Recall, Visual Scanning, and Verbal Fluency. Solid cooking fuel was used by 17% of the full sample but was more common in rural areas. Solid fuel users also had lower socioeconomic status. Compared to those using gas, solid fuel users had lower baseline scores and faster decline in Verbal Learning (ß = -0.18, p < 0.05), Visual Scanning (ß = -1.00, p < 0.001), and Verbal Fluency (ß = -0.33, p < 0.001). Indoor air pollution from solid cooking fuels may represent a modifiable risk factor for cognitive decline. Policy should focus on facilitating access to clean cooking fuels.

Fertility History and Cognitive Function in Late Life: The Case of Mexico.

OBJECTIVES: Mexico is aging rapidly, which makes identification of life-course factors influencing cognition a public health priority. We evaluate how the number of children one has relates to cognition in Mexico, a rapidly aging country that experienced fertility declines across recent cohorts of older people. METHOD: We analyze older adults (age 50+, n = 11,380) from the 2015 Mexican Health and Aging Study. Respondents were categorized by number of children ever born (0-1, 2-3, 4-5, 6+). Using ordinary least squares regression, we estimate independent associations between fertility history and cognition accounting for demographic, socioeconomic, health, and psychosocial factors. RESULTS: We observed an inverse U-shaped relationship between number of children (peaking at 2-3 children) and cognitive function, regardless of gender. In regression analyses adjusted for confounding variables, having 0-1 (vs 2-3 children) was associated with poorer cognitive function only for females. Regardless of gender, having 6+ (vs 2-3 children) was associated with poorer cognitive function. These associations remained significant even after accounting for socioeconomic, health, employment, and psychosocial factors. DISCUSSION: Our results suggest fertility history may play a role in late-life cognitive health and provide evidence that both low and high fertility may relate to poorer cognitive function. We discuss differences by gender.

Educational Benefits and Cognitive Health Life Expectancies: Racial/Ethnic, Nativity, and Gender Disparities.

BACKGROUND AND OBJECTIVES: To examine racial/ethnic, nativity, and gender differences in the benefits of educational attainment on cognitive health life expectancies among older adults in the United States. RESEARCH DESIGN AND METHODS: We used data from the Health and Retirement Study (1998-2014) to estimate Sullivan-based life tables of cognitively healthy, cognitively impaired/no dementia, and dementia life expectancies by gender for older White, Black, U.S.-born Hispanic, and foreign-born Hispanic adults with less than high school, high school, and some college or more. RESULTS: White respondents lived a greater percentage of their remaining lives cognitively healthy than their minority Black or Hispanic counterparts, regardless of level of education. Among respondents with some college or more, versus less than high school, Black and U.S.-born Hispanic women exhibited the greatest increase (both 37 percentage points higher) in the proportion of total life expectancy spent cognitively healthy; whereas White women had the smallest increase (17 percentage points higher). For men, the difference between respondents with some college or more, versus less than high school, was greatest for Black men (35 percentage points higher) and was lowest for U.S.-born Hispanic men (21 percentage points higher). DISCUSSION AND IMPLICATIONS: Our results provide evidence that the benefits of education on cognitive health life expectancies are largest for Black men and women and U.S.-born Hispanic women. The combination of extended longevity and rising prevalence of Alzheimer's disease points to the need for understanding why certain individuals spend an extended period of their lives with poor cognitive health.

Spousal Support, Spousal Strain, and Loneliness in Older Mexican Couples.

OBJECTIVES: A growing body of research has identified factors related to loneliness among older adults. Fewer have investigated predictors of loneliness within married couples. This analysis investigates how spousal support and strain relate with loneliness within older couples (age 50+), and whether these associations are modified by functional limitation. The study focuses on Mexico, a country experiencing rapid aging occurring alongside historically limited institutional support for older adults, and where traditional gender roles extend to marriage. METHODS: The analytic sample consisted of 3,584 husband-wife dyads from the 2012 and 2015 Mexican Health and Aging Study. Loneliness was measured using the Three-Item Loneliness Scale. Associations between spousal support, strain, and loneliness were estimated within husband-wife dyads using the Actor-Partner Interdependence Model. RESULTS: Experiencing more spousal support was associated with less loneliness, whereas experiencing spousal strain was associated with more loneliness 3 years later among married adults. The associations between spousal support/strain and loneliness were stronger among husbands with limitations in activities of daily living (ADL) when compared to their counterparts without ADL limitations. DISCUSSION: Among married adults, spousal support and strain may be important factors to understand loneliness within marriage. Effects should be interpreted within the context of functional limitation.

Elevated Depressive Symptoms and the Risk of Stroke among the Mexican Older Population.

BACKGROUND/OBJECTIVES: Several longitudinal studies in high-income countries suggest that depression increases stroke risk. However, few prior studies have evaluated this association in low- and middle-income countries (LMICs), where rapidly aging populations may have markedly different vascular risk profiles. DESIGN: Prospective cohort study. SETTING: The Mexican Health and Aging Study is a national population-based study of older adults in Mexico. PARTICIPANTS: A total of 10,693 Mexican adults aged 50 and older enrolled in 2001 with no history of prior stroke. MEASUREMENTS: Depressive symptoms were assessed with a modified 9-item Centers for Epidemiologic Studies Depression Scale (elevated depressive symptom cutoff ≥5) in 2001 and 2003. We evaluated associations between baseline and short-term (2-year) changes in elevated depressive symptoms (categorized as stable low, recently remitted, recent-onset, or stable high symptoms) with incident self-reported or next-of-kin reported doctor-diagnosed stroke through 2015 using Cox proportional hazards models and sensitivity analyses applying inverse probability weights. RESULTS: Over an average follow-up of 11.4 years (standard deviation = 4.2), 10,693 respondents reported 546 incident strokes. Individuals with elevated baseline depressive symptoms experienced a moderately higher hazard of incident stroke (hazard ratio [HR] = 1.13; 95% confidence interval [CI] = .95-1.36) compared with those without elevated baseline depressive symptoms. In analyses of short-term changes in elevated depressive symptoms (n = 8,808; 414 incident stokes), participants with recent-onset (HR = 1.38; 95% CI = 1.06-1.81) or stable high (HR = 1.42; 95% CI = 1.10-1.84) elevated depressive symptoms had a greater hazard of incident stroke compared to those with stable low/no depressive symptoms, whereas recently remitted (HR = 1.01; 95% CI = .74-1.37) symptoms was not associated with stroke hazard. CONCLUSION: Strategies to reduce depressive symptoms merit evaluation as approaches to prevent stroke in middle-income countries. Findings are similar to those in high-income countries but should be replicated in other LMICs.

The Association Between Spousal Education and Cognitive Ability Among Older Mexican Adults.

OBJECTIVES: Education and cognition are closely associated, yet the role of spousal education is not well understood. We estimate the independent effects of own and spousal education on cognitive ability in late-life in Mexico, a developing country experiencing rapid aging. METHOD: We analyzed 4,017 married dyads (age 50+) from the 2012 Mexican Health and Aging Study. Cognitive ability for married adults was a factor score from a single factor model. Using seemingly unrelated regression, we test whether spousal education influences older adults' cognitive ability, whether associations are explained by couple-level socioeconomic position, health and health behaviors, and social support, and whether associations differed by gender. RESULTS: Education and cognitive ability were correlated within couples. Higher spousal education was associated with better cognitive ability. Associations between spousal education and cognitive ability were independent of own education, did not differ by gender, and remained significant even after adjustment for couple-level socioeconomic position, health and health behaviors, and perceived social support. DISCUSSION: In addition to own education, spousal education was associated with better cognitive ability, even at relatively low levels of education. We discuss the possibility that spousal education may improve cognition via transmission of knowledge and mutually reinforcing cognitively stimulating environments.

Late life depressive symptoms and cognitive function among older Mexican adults: the past and the present.

Objective: To evaluate associations between depression and individual cognitive domains and how changes in depressive symptoms relate to cognition three years later in the context of Mexico, a developing country experiencing rapid aging.Method: Data comes from the 2012 and 2015 waves of the Mexican Health and Aging Study (n = 12,898, age 50+). Depression is ascertained using a modified Center for Epidemiologic Studies - Depression Scale. Cognition is assessed using verbal learning, verbal memory, visual scanning, verbal fluency, visuospatial ability, visual memory, and orientation tasks. Depressive symptoms and cognitive functioning were both measured in 2012 and 2015. Scores across cognitive domains are modeled using ordinary least squares regression, adjusting for demographic, health, and economic covariates.Results: When depression and cognition were measured concurrently in 2015, depression exhibited associations with all cognitive domains. When considering a respondent's history of depression, individuals who had elevated depressive symptoms in 2012 and recovered by 2015 continued to exhibit poorer cognitive function in 2015 in verbal learning, verbal memory, visual scanning, and verbal fluency tasks compared to individuals who were neither depressed in 2012 nor 2015.Conclusions: Depression was associated with cognition across cognitive domains among older Mexican adults. Despite improvements in depressive symptomatology, formerly depressed respondents continued to perform worse than their counterparts without a history of depression on several cognitive tasks. In addition to current mental health status, researchers should consider an individual's history of depression when assessing the cognitive functioning of older adults.

Religious Participation and Mortality Risk in Mexico.

OBJECTIVES: Although research suggests that religious involvement tends to favor longevity, most of this work has been conducted in the United States. This article explores the association between religious participation and all-cause mortality risk in Mexico. METHODS: We used data from the 2003-2015 Mexican Health and Aging Study (n = 14,743) and Cox proportional hazard regression models to assess the association between religious participation and all-cause mortality risk. RESULTS: Our key finding is that older Mexicans who participate once or more per week in religious activities tend to exhibit a 19% reduction in the risk of all-cause mortality than those who never participate. This estimate persisted with adjustments for health selection (chronic disease burden, activities of daily living, instrumental activities of daily living, cognitive functioning, and depressive symptoms), several potential mediators (social support, smoking, and drinking), and a range of sociodemographic characteristics. Although we observed considerable health selection due to physical health and cognitive functioning, we found no evidence of mediation. DISCUSSION: Our results confirm that religious participation is associated with lower all-cause mortality risk among older adults in Mexico. Our analyses contribute to previous research by replicating and extending the external validity of studies conducted in the United States, Israel, Denmark, Finland, and Taiwan.

Marital Power and Depressive Symptoms among Older Mexican Adults.

An extensive body of research documents marital status differences in health among older adults. However, few studies have investigated the heterogeneity in depressive symptomatology among older married adults living in developing countries. Our study investigates the interplay of gender and marital power dynamics for mental health among older Mexican adults. Our sample includes older married couples in the 2015 Wave of the Mexican Health and Aging Study (n=3,621 dyads). We use seemingly unrelated regression to model the association between self-reported distributions of decision-making power within marriages and depressive symptoms for husbands and wives. For approximately 41 per cent of couples, the husband and wife both reported an equal distribution of power in the marriage. Compared to those who reported an equal power distribution, husbands and wives who reported an imbalance of power (having more power or less power than their spouse) reported more depressive symptoms. Levels of depressive symptoms were higher in marriages characterised by an unequal balance of power. The relationship between equality in power and depressive symptoms is not explained by health care needs or living arrangements. Marital quality is an important factor for understanding depressive symptoms among older Mexican adults.

Racial/Ethnic and Nativity Differences in Cognitive Life Expectancies Among Older Adults in the United States.

BACKGROUND AND OBJECTIVES: To document racial/ethnic and nativity differences by gender in cognitive life expectancies among older adults in the United States. RESEARCH DESIGN AND METHODS: Sullivan-based life tables were used to estimate cognitively normal, cognitively impaired/no dementia (CIND), and dementia life expectancies by gender for White, Black, U.S.-born Hispanic, and foreign-born Hispanic adults 50 years and older in the Health and Retirement Study. RESULTS: Among women, the number of years spent living with dementia for Whites, Blacks, U.S.-born Hispanics, and foreign-born Hispanics was 1.6, 3.9, 4.7, and 6.0 years, respectively. For men, Whites lived 1.1 years with dementia compared to 3.1 years for Blacks, 3.0 years for U.S.-born Hispanics and 3.2 years for foreign-born Hispanics. Similar patterns were observed for race/ethnic and nativity differences in CIND life expectancies. Blacks and Hispanics spend a larger fraction of their remaining years with CIND and dementia relative to Whites, regardless of gender. Foreign-born Hispanic men and women and Black men are particularly disadvantaged in the proportion of years spent after age 50 with CIND and/or dementia. DISCUSSION AND IMPLICATIONS: Disparities in cognitive life expectancies indicate that intervention strategies should target the specific needs of minority and immigrant older adults with dementia. Given that education is a strong predictor of cognitive health, improving access to the social and economic resources that delay dementia onset is key to improving the well-being of diverse older adults.

Age of Migration Differentials in Life Expectancy With Cognitive Impairment: 20-Year Findings From the Hispanic-EPESE.

Background and Objectives: To examine differences in life expectancy with cognitive impairment among older Mexican adults according to nativity (U.S.-born/foreign-born) and among immigrants, age of migration to the United States. Research Design and Methods: This study employs 20 years of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to estimate the proportion of life spent cognitively healthy and cognitively impaired prior to death among older Mexican adults residing in the southwestern United States. We combine age-specific mortality rates with age-specific prevalence of cognitive impairment, defined as a Mini-Mental Status Exam score of less than 21 points to calculate Sullivan-based life table models with and without cognitive impairment in later life. Results: Foreign-born Mexican immigrants have longer total life expectancy and comparable cognitive healthy life expectancy regardless of gender compared to U.S.-born Mexican-Americans. However, the foreign-born spend a greater number of years after age 65 with cognitive impairment relative to their U.S.-born counterparts. Furthermore, we document an advantage in life expectancy with cognitive impairment and proportion of years after age 65 cognitively healthy among mid-life immigrant men and women relative to early- and late-life migrants. Discussion and Implications: The relationship between nativity, age of migration, and life expectancy with cognitive impairment means that the foreign-born are in more need of support and time-intensive care in late life. This issue merits special attention to develop appropriate and targeted screening efforts that reduce cognitive decline for diverse subgroups of older Mexican-origin adults as they age.

Indoor air pollution and cognitive function among older Mexican adults.

BACKGROUND: A growing body of research suggests exposure to high levels of outdoor air pollution may negatively affect cognitive functioning in older adults, but less is known about the link between indoor sources of air pollution and cognitive functioning. We examine the association between exposure to indoor air pollution and cognitive function among older adults in Mexico, a developing country where combustion of biomass for domestic energy remains common. METHOD: Data come from the 2012 Wave of the Mexican Health and Aging Study. The analytic sample consists of 13 023 Mexican adults over age 50. Indoor air pollution is assessed by the reported use of wood or coal as the household's primary cooking fuel. Cognitive function is measured with assessments of verbal learning, verbal recall, attention, orientation and verbal fluency. Ordinary least squares regression is used to examine cross-sectional differences in cognitive function according to indoor air pollution exposure while accounting for demographic, household, health and economic characteristics. RESULTS: Approximately 16% of the sample reported using wood or coal as their primary cooking fuel, but this was far more common among those residing in the most rural areas (53%). Exposure to indoor air pollution was associated with poorer cognitive performance across all assessments, with the exception of verbal recall, even in fully adjusted models. CONCLUSIONS: Indoor air pollution may be an important factor for the cognitive health of older Mexican adults. Public health efforts should continue to develop interventions to reduce exposure to indoor air pollution in rural Mexico.

Cognition and Context: Rural-Urban Differences in Cognitive Aging Among Older Mexican Adults.

OBJECTIVE: To describe differences in cognitive functioning across rural and urban areas among older Mexican adults. METHOD: We include respondents aged 50+ in the 2012 Mexican Health and Aging Study (MHAS). Cognitive functioning by domain is regressed as a function of community size. The role of educational attainment in explaining rural/urban differences in cognitive functioning is examined. RESULTS: Respondents residing in more rural areas performed worse across five cognitive domains. The majority, but not all, of the association between community size and cognitive functioning was explained by lower education in rural areas. DISCUSSION: Respondents residing in more rural areas were disadvantaged in terms of cognitive functioning compared with those residing in more urban areas. Poorer cognitive functioning in late life may be the result of historical educational disadvantage in rural areas or selection through migration from rural to urban regions for employment.