Variation in Adult Cognition Across Domains and Life Course Place Effects in the UK.

This study explores the role that place of birth and place of residence have in variation in cognition in adulthood in the UK. We take advantage of both the large sample size and number of cognitive domains in the UK Biobank to estimate the effect of place of birth and place of residence on adulthood cognition using multilevel modeling. We find, consistent with studies in the US, that place effects at both time points contribute modest variation (<3% of the variation) across all measured cognitive domains, suggesting a relative lack of contribution of shared environments in explaining future Alzheimer's Disease and Related Dementias. Moreover, the geographical contribution to cognitive function in adulthood was slightly larger for females than for males. This study is among the first to explore the impact of both the independent and joint associations of place of birth and place of residence with different cognitive domains.

Educational attainment, family background and the emergence of pain gradients in adulthood.

Current studies have indicated that the number of individuals living with pain has risen in recent years, with nearly half of all adults in some countries living with some form of pain. Such trends have prompted researchers to explore differences in pain across different sociodemographic groups, with a dominant focus on educational attainment. However, much of the studies fail to consider the confounding role of early life characteristics, such as family background. Using data on over 400,000 individuals from the UK Biobank, we look at how educational attainment is associated with nine different domains of pain (headache, facial, neck, back, hip, knee, stomach, all over, and no pain). Ultimately, we find that compared to those with no educational credentials, education is associated with anywhere between a 0.1-15% change in the likelihood of reporting pain, depending on pain type and education level, with the greatest change occurring in those with the highest level. Yet, when accounting for family background characteristics in the form of sibling fixed effects, nearly all relationships between education and pain fell by either 50% or were eliminated. We ultimately conclude that failure to consider early life characteristics, such as family background characteristics may lead to inflated estimates of pain, and that future research should delve into early life exposures and their influence on pain in adulthood.

Area-Level Infant Mortality Exposure in Early Life and Alzheimer's Disease Mortality: Examining Variation Based on Age, Sex, and Place of Birth.

BACKGROUND: Growing evidence suggests that critical periods in early life may contribute to one's risk of Alzheimer's disease and related dementias (ADRD) in later life. In this paper we explore the role that exposure to infant mortality plays in later life ADRD. OBJECTIVE: To determine if exposure to early life infant mortality is associated with later mortality from ADRD. Also, we explore how these associations differ by sex and age group, along with the role of state of birth and competing risks of death. METHODS: We use a sample of over 400,000 individuals aged 50 and above with the NIH-AARP Diet and Health Study with mortality follow-up, allowing us to examine how early life infant mortality rates along with other risk factors play in one's individual mortality risk. RESULTS: We show that infant mortality rates are associated with death from ADRD among those under 65 years of age, but not those over 65 at baseline interview. Moreover, when factoring in competing risks of death, the associations are relatively unchanged. CONCLUSION: These results suggest that those exposed to worse adverse conditions during critical periods increase their likelihood of death from ADRD earlier than average, due to that exposure increasing their susceptibility to develop illness later on in life.

Conceptualizing rurality: The impact of definitions on the rural mortality penalty.

Background: In the U.S., inequality is widespread and still growing at nearly every level conceivable. This is vividly illustrated in the long-standing, well-documented inequalities in outcomes between rural and urban places in the U.S.; namely, the rural mortality penalty of disproportionately higher mortality rates in these areas. But what does the concept of "rural" capture and conjure? How we explain these geographic differences has spanned modes of place measurement and definitions. We employ three county-level rural-urban definitions to (1) analyze how spatially specific and robust rural disparities in mortality are and (2) identify whether mortality outcomes are dependent on different definitions. Methods: We compare place-based all-cause mortality rates using three typologies of "rural" from the literature to assess robustness of mortality rates across these rural and urban distinctions. Results show longitudinal all-cause mortality rate trends from 1968 to 2020 for various categories of urban and rural areas. We then apply this data to rural and urban geography to analyze the similarity in the distribution of spatial clusters and outliers in mortality using spatial autocorrelation methodologies. Results: The rural disadvantage in mortality is remarkably consistent regardless of which rural-urban classification scheme is utilized, suggesting the overall pattern of rural disadvantage is robust to any definition. Further, the spatial association between rurality and high rates of mortality is statistically significant. Conclusion: Different definitions yielding strongly similar results suggests robustness of rurality and consequential insights for actionable policy development and implementation.

State of birth and cardiovascular disease mortality: Multilevel analyses of the National Longitudinal Mortality Study.

Cardiovascular disease (CVD) is the leading contributor to mortality in the United States. Previous studies have linked early life individual and family factors, along with various contemporaneous place-based exposures to differential individual CVD mortality risk. However, the impacts of early life place exposures and how they compare to the effects of an individual's current place of residence on CVD mortality risk is not well understood. Using the National Longitudinal Mortality Study, this research examined the effects of both state of birth and state of residence on individual's risk of CVD mortality. We estimated individual mortality risk by estimating multi-level logistic regression models. We found that during a follow-up period of 11 years, 18,292 (4.2%) out of 433,345 participants died from CVD. The impact of state of birth on subsequent CVD mortality risk are greater than state of residence, even after adjusting for socio-demographic factors. Individuals who were born in certain states such as Tennessee, Kentucky, and Pennsylvania on average had higher CVD mortality risk. Conversely, those born in California, North Dakota, and Montana were found to have lower risk, no matter where they presently live. This study implies that early life state-level environments may be more prominent to individual's CVD mortality risk, compared to the state in which one lives. Future research should address specific mechanisms through which state of birth may affect people's risk of CVD mortality.

Association and pathways of birth in the stroke belt on old age dementia and stroke Mortality.

This paper uses data from the Diet and Health Study (DHS) to examine associations between being born in a "stroke belt" state and old age stroke and mortality outcomes. Adding to prior work that used administrative data, our paper explores educational and health mechanisms that are both stratified by geography and by mortality outcomes. Using logistic regression, we first replicate earlier findings of elevation in risk of dementia mortality (OR 1.13, CI [1.07, 1.20]) and stroke mortality (OR 1.17, CI [1.07, 1.29]) for white individuals born in a stroke belt state. These associations are largely unaffected by controls for educational attainment or by experiences with surviving a stroke and are somewhat attenuated by controls for self-rated health status in old age. The results suggest a need to consider additional life course mechanisms in order to understand the persistent effects of place of birth on old age mortality patterns.

Geographic variation in Alzheimer's disease mortality.

OBJECTIVE: Accumulating evidence suggests the possibility that early life exposures may contribute to risk of Alzheimer's Disease (AD). This paper explores geographic disparities in AD mortality based on both state of residence in older age as well as state of birth measures in order to assess the relative importance of these factors. METHODS: We use a subset of a large survey, the NIH-AARP Diet and Health Study, of over 150,000 individuals aged 65-70 with 15 years of mortality follow-up, allowing us to study over 1050 cases of AD mortality. We use multi-level logistic regression, where individuals are nested within states of residence and/or states of birth, to assess the contributions of place to AD mortality variation. RESULTS: We show that state of birth explains a modest amount of variation in AD mortality, approximately 4%, which is consistent with life course theories that suggest that early life conditions can produce old age health disparities. However, we also show that nearly all of the variation from state of birth is explained by state of residence in old age. CONCLUSIONS: These results suggest that later life factors are potentially more consequential targets for intervention in reducing AD mortality and provide some evidence against the importance of macro-level environmental exposures at birth as a core determinant of later AD.

The effects of education on cognition in older age: Evidence from genotyped Siblings.

A growing literature has sought to tie educational attainment with later-life cognition and Alzheimer's disease outcomes. This paper leverages sibling comparisons in educational attainment as well as genetic predictors (polygenic scores) for cognition, educational attainment, and Alzheimer's disease to estimate effects of educational attainment on cognition in older age in the United Kingdom. We find that the effects of education on cognition are confounded by family background factors (~40%) and by genetics (<10%). After adjustments, we continue to find large effects of education. College graduates have cognition scores that are approximately 0.75 SD higher than those who report no credentials. We also find evidence that educational effects on cognition are smaller for those with high polygenic scores for Alzheimer's disease.