Carlos Díaz-Venegas

Racial and ethnic differences in cognitive function among older adults in the USA

Examine differences in cognition between Hispanic, non‐Hispanic black (NHB), and non‐Hispanic white (NHW) older adults in the United States.

Differences in the Progression of Disability: A U.S.–Mexico Comparison

Abstract Objectives This article seeks to document the progression of disability in a developing country by implementing a model to examine how this process compares to a developed country. Methods Data come from the Mexican Health and Aging Study (MHAS), including a baseline survey in 2001 and a follow-up in 2003, and from the U.S. Health and Retirement Study (HRS), using the 2000 and 2002 waves. An ordinal logistic regression approach is used to examine a progression of disability that considers (a) no disability, (b) mobility problems, (c) mobility plus limitations with instrumental activities of daily living, (d) mobility plus limitations with activities of daily living (ADLs), (e) limitations in all three areas and (f) death. Results In both data sets, approximately 44% of the sample remained in the same level of disability at the 2-year follow-up. However, the progression of limitations with two disabilities differs by gender in the MHAS but is consistent for both men and women in the HRS. Discussion Our model reflects the importance of ADLs in the disablement process in Mexico. We speculate that the difference in lifetime risk profiles and cultural context might be responsible for the divergence in the progression of disability by gender.

Trajectories of limitations in activities of daily living among older adults in Mexico, 2001–2012

BACKGROUNDnTrajectories of disability are an essential component to understand the burden of disability at the societal level. Longitudinal studies, compared to cross-national studies, enable a better analysis of the progression of physical limitations among the elderly. However, information on disability dynamics in developing countries is limited.nnnOBJECTIVESnThis paper examines the changes in activities of daily living (ADLs) in an 11-yr. period in the Mexican elderly population aged 60 or older and identifies how sociodemographic variables alter these trajectories.nnnMETHODSnThe data come from the Mexican Health and Aging Study (MHAS), a national sample of adults born in 1951 or earlier, including a baseline survey in 2001 and follow-ups in 2003 andxa02012.nnnRESULTSnThe ADL score increased on average by 0.03 for every year respondents aged after 60. In contrast, the ADL score was reduced by 0.06 for every additional year of education.nnnCONCLUSIONSnAge, gender, and years of education were confirmed to influence the trajectories of ADL limitations. Understanding the patterns of deterioration of functional limitations will help public health policies to better serve the population.

Family size and old-age wellbeing: effects of the fertility transition in Mexico

ABSTRACT The present study aims to determine how family size affects psycho-social, economic and health wellbeing in old age differently across two cohorts with declining fertility. The data are from the 2012 Mexican Health and Ageing Study (MHAS) including respondents aged 50+ (N = 13,102). Poisson (standard and zero-inflated) and logistic regressions are used to model determinants of wellbeing in old age: psycho-social (depressive symptoms), economic (consumer durables and insurance) and health (chronic conditions). In the younger cohort, having fewer children is associated with fewer depressive symptoms and chronic conditions, and better economic wellbeing. For the older cohort, having fewer children is associated with lower economic wellbeing and higher odds of being uninsured. Lower fertility benefited the younger cohort (born after 1937), whereas the older cohort (born in 1937 or earlier) benefited from lower fertility only in chronic conditions. Further research is needed to continue exploring the old-age effects of the fertility transition.

The progression of disability among older adults in Mexico

Abstract Purpose: This paper seeks to document the progression of disability in a developing country and to examine gender differences in this process. Methods: The data come from the Mexican Health and Aging Study (MHAS), a nationally representative sample of older adults. An ordinal logistic regression (nu2009=u20093283) is used to measure the progression of disability that considers: (1) no disability, (2) mobility problems, (3) mobility problems with IADLs limitations, (4) mobility problems with ADLs limitations, (5) combinations of the latter three and (6) death. Results: Approximately 43% of the sample remained in the same level of disability after 2 years. The patterns of progression with two disabilities differ for men and women. Conclusions: Our model reflects the importance of separating ADLs and IADLs in the study of disability progression in Mexico. Varying risk profiles and cultural differences might influence the divergent disability paths followed by each gender. Implications for Rehabilitation The disablement process involving transitions from mobility impairments to IADL and ADL limitations seen in developed countries differs for older adults in Mexico. Cultural differences may influence the progression from non-disabled to becoming disabled in different ways for females in developing countries like Mexico. One-fifth of individuals showed greater function and independence over time, suggesting that the disablement process is reversible. This finding highlights the need to focus on improving mobility, ADL, and IADL skills to facilitate successful aging. Although disability is often conceptualised as a combination of ADL and IADL limitations, gender differences seen in Mexico indicate the need to separate ADL and IADL when developing approaches to prevent or ameliorate disability.

Cognitive Functioning of U.S. Adults by Race and Hispanic Origin

The U.S. older adult population is becoming increasingly diverse. The evidence from research using data from diverse older adult populations indicates that Hispanics have poorer performance on cognitive tests than older non-Hispanic whites (NHW). However, the evidence that older Hispanics are at an increased risk for Alzheimer’s disease or related dementia (ADRD) than NHW is less clear. Interpreting the evidence from existing research on disparities between NHWs and Hispanics is complicated by the fact that few studies have differentiated between Hispanic subgroups by country of origin. In this chapter, we use the ethnic descriptor of Hispanic as interchangeable with Latino. We summarize the current evidence on disparities between Hispanics and NHW in cognitive functioning and ADRD, and factors that may contribute to these disparities. This summary focuses on the rationale for considering specific Hispanic populations when studying differences in cognitive functioning between Hispanics and NHWs. Finally, we present and discuss the findings from an analysis of data from the 2010 wave of the Health and Retirement Study (n = 18,982) in which we examine differences in three cognitive domains by race/ethnicity, including four Hispanic subgroups. In this analysis, all Hispanic subgroups, except Cubans, had significantly lower scores for all cognitive domains compared to NHWs, with Puerto Ricans showing the lowest scores among Hispanics.

Cross-national health comparisons using the Rasch model: findings from the 2012 US Health and Retirement Study and the 2012 Mexican Health and Aging Study

PurposeCross-national comparisons of patterns of population aging have emerged as comparable national micro-data have become available. This study creates a metric using Rasch analysis and determines the health of American and Mexican older adult populations.MethodsSecondary data analysis using representative samples aged 50 and older from 2012 U.S. Health and Retirement Study (nu2009=u200920,554); 2012 Mexican Health and Aging Study (nu2009=u200914,448). We developed a function measurement scale using Rasch analysis of 22 daily tasks and physical function questions. We tested psychometrics of the scale including factor analysis, fit statistics, internal consistency, and item difficulty. We investigated differences in function using multiple linear regression controlling for demographics. Lastly, we conducted subgroup analyses for chronic conditions.ResultsThe created common metric demonstrated a unidimensional structure with good item fit, an acceptable precision (person reliabilityu2009=u20090.78), and an item difficulty hierarchy. The American adults appeared less functional than adults in Mexico (βxa0=u2009−u20090.26, pu2009<u20090.0001) and across two chronic conditions (arthritis, βxa0=u2009−u20090.36; lung problems, βxa0=u2009−u20090.62; all pu2009<u20090.05). However, American adults with stroke were more functional than Mexican adults (βxa0=u20090.46, pu2009=u20090.047).ConclusionsThe Rasch model indicates that Mexican adults were more functional than Americans at the population level and across two chronic conditions (arthritis and lung problems). Future studies would need to elucidate other factors affecting the function differences between the two countries.

Life expectancy with and without cognitive impairment by diabetes status among older Americans

Diabetes affects mortality and cognitive functioning. It is not known how diabetes influences life expectancy (LE) with and without cognitive impairment. We seek to examine age at onset of cognitive impairment and life expectancy (LE) with and without cognitive impairment by diabetes status among middle- and older-aged Americans. Data come from the U.S. Health and Retirement Study 2000–2012 linked to the National Death Index (N = 13,687). We use multinomial regression models stratified by gender and controlling for age, education and race/ethnicity to estimate diabetes-status specific transition probabilities, then use a Markov chain matrix population model to calculate age at onset of cognitive impairment and LE with and without cognitive impairment by diabetes status at age 50. LE at age 50 was 27.6 (men) and 32.1 (women). From age 50, those with diabetes had a first incidence of cognitive impairment 3 (men) and 4 (women) years earlier than those without. Diabetes reduced total LE by 5–7 years and cognitively healthy LE by 4–6 years. Those with diabetes lived one year less in a cognitively impaired state than those without. Over 80% of the lower LE associated with diabetes is attributable to the loss of cognitively-healthy years. Those with diabetes have a shorter LE with cognitive impairment because of higher mortality. In analyses by educational attainment, education was strongly protective of cognitive health, yet diabetes was associated with lower age of cognitive impairment onset and fewer cognitive healthy years lived in all educational groups. The excess mortality because of diabetes may be decreasing. If the mortality decline is not coupled with a comparable decline in the risk of cognitive impairment, the population level burden of impaired cognition may grow larger.