Collin F. Payne

Aging in the Americas: Disability-free Life Expectancy Among Adults Aged 65 and Older in the United States, Costa Rica, Mexico, and Puerto Rico

Objectives To estimate and compare disability-free life expectancy (DFLE) and current age patterns of disability onset and recovery from disability between the United States and countries in Latin America and the Caribbean. Method Disability is measured using the activities of daily living scale. Data come from longitudinal surveys of older adult populations in Costa Rica, Mexico, Puerto Rico, and the United States. Age patterns of transitions in and out of disability are modeled with a discrete-time logistic hazard model, and a microsimulation approach is used to estimate DFLE. Results Overall life expectancy for women aged 65 is 20.11 years in Costa Rica, 19.2 years in Mexico, 20.4 years in Puerto Rico, and 20.5 years in the United States. For men, these figures are 19.0 years in Costa Rica, 18.4 years in Mexico, 18.1 years in Puerto Rico, and 18.1 years in the United States. Proportion of remaining life spent free of disability for women at age 65 is comparable between Mexico, Puerto Rico, and the United States, with Costa Rica trailing slightly. Male estimates of DFLE are similar across the four populations. Discussion Though the older adult population of Latin America and the Caribbean lived many years exposed to poor epidemiological and public health conditions, their functional health in later life is comparable with the older adult population of the United States.

Physical Function in an Aging Population in Rural South Africa : Findings From HAALSI and Cross-National Comparisons With HRS Sister Studies

Objectives We use recently-collected data from the Health and Aging in Africa: a Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) cohort from Agincourt, South Africa, to describe physical functioning in this aging population, and place the overall level and age-trajectories of physical health in the context of other Health and Retirement Study (HRS) sister studies in low- and middle-income countries (LMICs). Method We conduct multiple regression to estimate associations of physical functioning assessed from both self-report (activities of daily living [ADL] limitation, self-reported health) and performance (grip strength, gait speed) with socio-demographic and health characteristics in HAALSI, and use fully-interacted regression models to compare age-patterns of physical functioning outcomes cross-nationally. Results Gender differences in self-reported health are minimal, and men had 30% higher odds of being ADL limited controlling for socio-demographic and health characteristics. Measured physical performance is closely tied with socioeconomic conditions, but self-reported measures have a much smaller or weaker socioeconomic gradient. In international age-adjusted comparisons, the HAALSI sample had lower physical performance outcomes than most comparison populations. Discussion As the first HRS sister study undertaken in Africa, HAALSI adds vital information on population aging and health in the region. Continuing waves of HAALSI data will be a key resource for understanding differences in the complex processes of disability across LMIC contexts.

The Demography of Mental Health Among Mature Adults in a Low-Income, High-HIV-Prevalence Context

Very few studies have investigated mental health in sub-Saharan Africa (SSA). Using data from Malawi, this article provides a first picture of the demography of depression and anxiety (DA) among mature adults (aged 45 or older) in a low-income country with high HIV prevalence. DA are more frequent among women than men, and individuals affected by one are often affected by the other. DA are associated with adverse outcomes, such as poorer nutrition intake and reduced work efforts. DA also increase substantially with age, and mature adults can expect to spend a substantial fraction of their remaining lifetime—for instance, 52 % for a 55-year-old woman—affected by DA. The positive age gradients of DA are not due to cohort effects, and they are in sharp contrast to the age pattern of mental health that has been shown in high-income contexts, where older individuals often experience lower levels of DA. Although socioeconomic and risk- or uncertainty-related stressors are strongly associated with DA, they do not explain the positive age gradients and gender gap in DA. Stressors related to physical health, however, do. Hence, our analyses suggest that the general decline of physical health with age is the key driver of the rise of DA with age in this low-income SSA context.

Cohort Profile: Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)

Cohort Profile : Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)

The population-level impact of public-sector antiretroviral therapy rollout on adult mortality in rural Malawi

BACKGROUND Recent evidence from health and demographic surveillance sites (HDSS) has shown that increasing access to antiretroviral therapy (ART) is reducing mortality rates in sub-Saharan Africa (SSA). However, due to limited vital statistics registration in many of the countries most affected by the HIV/AIDS epidemic, there is limited evidence of the magnitude of ART’s effect outside of specific HDSS sites. This paper leverages longitudinal household/family roster data from the Malawi Longitudinal Survey of Families and Health (MLSFH) to estimate the effect of ART availability in public clinics on population-level mortality based on a geographically dispersed sample of individuals in rural Malawi. OBJECTIVE We seek to provide evidence on the population-level magnitude of the ART-associated mortality decline in rural Malawi and confirm that this population is experiencing similar declines in mortality as those seen in HDSS sites. METHODS We analyze longitudinal household/family-roster data from four waves of the MLSFH to estimate mortality change after the introduction of ART to study areas. We analyze life expectancy using the Kaplan–Meier estimator and examine how the mortality hazard changed over time by individual characteristics with Cox regression. RESULTS In the four years following rollout of ART, life expectancy at age 15 increased by 3.1 years (95% CI 1.1, 5.1), and median length of life rose by over ten years. CONTRIBUTION Our observations show that the increased availability of ART resulted in a substantial and sustained reversal of mortality trends in SSA and assuage concerns that the post-ART reversals in mortality are not occurring at the same magnitude outside of specific HDSSs.

Cross-sectional relationship between haemoglobin concentration and measures of physical and cognitive function in an older rural South African population

Background Age cohort differences in haemoglobin concentrations and associations with physical and cognitive performance among populations of lower income and middle-income countries have not previously been described. We examined the association between these factors among older men and women in rural South Africa. Methods We analysed cross-sectional data from a population-based study of rural South African men and women aged 40 and over (n=4499), with data drawn from questionnaire responses, a cognitive battery, objective physical function tests and blood tests. Anaemia was defined as a haemoglobin concentration <12 g/dL for women and <13 g/dL for men. We related haemoglobin concentrations to each of age, grip strength, walk speed and a latent cognitive function z-score for men and women separately. We used unadjusted correlations and linear models to adjust for comorbidities and inflammation. Results In total, 1042 (43.0%) women and 833 (40.1%) men were anaemic. Haemoglobin concentrations were inversely correlated with age for men but not for women; in adjusted analyses, haemoglobin was 0.3 g/dL lower per decade older for men (95% CI 0.2 to 0.4 g/dL). In adjusted analyses, haemoglobin concentration was independently associated with grip strength in women (B=0.391, 95% CI 0.177 to 0.605), but this did not reach significance in men (B=0.266, 95% CI −0.019 to 0.552); no associations were observed between haemoglobin levels and walk speed or cognitive score. Conclusions Anaemia was prevalent in this study population of middle-aged and older, rural South African adults, but in contrast to high-income countries, it was not associated with poor physical or cognitive function. Our findings need to be replicated in other populations.