Populations

Depression is one of the most prevalent mental health conditions in middle and late adulthood, contributing substantially to morbidity, mortality, and reduced quality of life. However, limited research has examined the mechanisms linking genetic predisposition and early protective environments to long-term mental health trajectories. Guided by a life course health development perspective, this study investigated how depression polygenic scores (G) and protective childhood family environments (E) interplay to shape depressive symptom trajectories from mid- to late adulthood. We analyzed longitudinal data of 14 waves from the Health and Retirement Study (1994–2020; N = 4817), estimating linear mixed-effects models of depressive symptoms using the validated CES-D scale. Early protective environments were measured by indicators of family structure stability, non-abusive and substance-free parenting, positive parent–child relationships, and parental support. Results showed that genetic predisposition and protective family environments jointly influence depression trajectories across the life course. Specifically, individuals with both low genetic risk and high environmental protection had the lowest depressive symptoms over time. Importantly, when only one favorable factor was present, protective family environments offered a stronger lifelong benefit than low genetic risk. These findings extend prior research by demonstrating that supportive childhood environments can mitigate genetic vulnerability, shaping healthier long-term mental health trajectories. This work underscores the need for early family-based interventions to reduce depression risk, enhance resilience, and promote longevity. Full article

Mortality studies comparing married men to never-married or formerly married men have consistently found that married men have a noticeable mortality advantage. This paper takes a novel perspective—examining mortality outcomes from the perspective of married men only and comparing those who coreside with any parents, in-laws, or their spouse only. The analyses use CenSoc data set, consisting of the 1940 Full Count United States Census linked to the Social Security Administration Death Master Files and includes 1.7 million married men between the ages of 21 and 45 years old residing with their spouse, and who died between 1975 and 2005. The results show that married men who live with only a spouse but no parental generations have an older age at death, and being a household head has an additional advantage. Living with either or both of their parents is associated with a reduction in life of 4 months, or 2 months for those who live with their in-laws. The conclusion reached is that longevity is associated with the possible burden of living with one’s parents, coupled with the reasons that may have led to the particular living arrangement. The effect of coresidence is, in turn, filtered through expectations about intergenerational relationships and norms regarding coresidence. The coresidence experience can become part of a trajectory, leading to declines in longevity. Full article

Providing culturally responsive, trauma-informed afterschool programming is a promising intervention to promote the adjustment, educational achievement, and well-being of newly arrived refugee and immigrant children. Connecting Communities and Multilingual Learners (CCML) is a local nonprofit organization in the Southeastern part of the United States that provides this type of programming to newly arrived families. To better understand their impact on children, CCML aimed to examine its model of programming via a mixed methods, strengths-focused evaluation. Evaluation efforts focused on describing the effects of the program on children at CCML’s flagship site in a robust urban center. Data were collected from students and facilitators at two times (beginning and end of the year) over one academic school year. Results revealed that CCML supported students’ socio-emotional well-being, English language acquisition, and cultural pride in positive and sustaining ways. Evidence from this study suggests that culturally responsive and trauma-informed programs offer promising, adaptable models for addressing the evolving needs of newly arrived refugee and immigrant youth in diverse community contexts. Full article

Lifetime reproductive output (LRO), also called lifetime reproductive success (LRS) is often described by its mean (total fertility rate or net reproductive rate), but it is in fact highly variable among individuals and often positively skewed. Several approaches exist to calculating the variance and skewness of LRO. These studies have noted that a major factor contributing to skewness is the fraction of the population that dies before reaching a reproductive age or stage. The existence of that fraction means that LRO has a zero-inflated distribution. This paper shows how to calculate that fraction and to fit a zero-inflated Poisson or zero-inflated negative binomial distribution to the LRO. We present a series of applications to populations before and after demographic transitions, to populations with particularly high probabilities of death before reproduction, and a couple of large mammal populations for good measure. The zero-inflated distribution also provides extinction probabilities from a Galton-Watson branching process. We compare the zero-inflated analysis with a recently developed analysis using convolution methods that provides exact distributions of LRO. The agreement is strikingly good. Full article

Past studies of urbanization in the United States have found that college-educated (power) couples migrate to metropolitan areas at higher rates than both educated single persons and other couples with less education. A common explanation is that power couples receive disproportionately high co-location benefits from cities and therefore migrate to urban areas more than other groups. This study leverages the Public Use Microdata Sets to understand urban residence rates for couples between 2007 and 2022, with a focus on couples attaining degrees beyond the bachelor’s level. The data allows couples to be classified into nine different power status categories based on joint educational attainment, along with categories for their sexual orientation and racial composition. Results from fixed-effects logit models reinforce previous work showing that couples at the highest levels of educational attainment reside in urban areas at higher rates than their otherwise equal peers. Urban residence rates are even stronger for more advanced degree holders generally, though the effect is disproportionately higher for black and Asian couples, while it is disproportionately weaker for some same-sex couples. The added nuance of these results provides important insight into the relationship between urban residency, educational attainment, and demographic characteristics. Full article

The article addresses the question of the relative importance of human population size and growth in relation to the environmental problems of planetary heating and biodiversity loss in the current, Anthropocene era. To what extent could policies to encourage lower fertility be justified, while observing that this subject is an inherently contested one. It is proposed that a helpful distinction can be made between specific threats to habitats and biodiversity, as opposed to those related to global energy use and warming. Pressures of over-population can be important in relation to the former. But with regard to the latter—rising per capita energy usage—reduced fertility has historically been positively, not negatively correlated. A case can be made that the high-fertility nations of sub-Saharan Africa could benefit from culturally respectful fertility reduction policies. However, where planetary heating is concerned, it is the hydrocarbon-based, per capita energy-consumption patterns of already low-fertility populations on the other five inhabited continents that is rather more critical. While it will be helpful to stabilise global human population, this cannot be viewed as a solution to the climate crisis problem of this century. That requires relentless focus on reducing hydrocarbon use and confronting the rising inequality since c.1980 that has been exacerbating competitive materialist consumerism. This involves the ideological negotiation of values to promote a culture change that understands and politically embraces a new economics of both human and planetary balance, equity, and distribution. Students of populations can contribute by re-assessing what can be the appropriate demographic units and measures for policies engaging with the challenges of the Anthropocene. Full article

Understanding the reintegration of returning rural migrants in China is crucial due to the large scale of return migration and its associated challenges. While existing research has largely focused on economic reintegration, this study broadens the scope to include social, cultural, and civic dimensions. Using data from the China Labor-force Dynamics Survey (CLDS) 2016 and employing multilevel ordered logistic regression, the research uncovers the following key patterns: (i) Determinants differ largely across dimensions; (ii) The roles of the same determinants can also differ significantly across dimensions; and (iii) There are significant community-level variations across dimensions. The findings emphasize that success in one dimension, such as economic reintegration, does not necessarily translate into success in others. Moreover, complex interconnections between dimensions reveal positive, negative, and non-linear relationships, underscoring the multidimensional nature of reintegration. These insights highlight the importance of considering multiple dimensions to fully understand the reintegration processes of returning migrants. Full article

Approximately 10% of the US Black diaspora were born either in Latin America and the Caribbean (LAC) or Sub-Saharan Africa (SSA), projected to account for a third of the Black US diaspora by 2060. Yet, details on foreign-born Black women’s labor and delivery (L&D) characteristics, such as the type of birth attendant, remain scarce. We used the National Center for Health Statistics 2016 to 2020 Natality data (n = 2,041,880). The associations between detailed maternal nativity (DMN) and the type of attendant at birth (i.e., physician, certified nurse-midwife (CNM), certified professional midwife (CPM)) among US-born, LAC-born, and SSA-born Black women were examined using multivariate multinomial regression. The study revealed that LAC-born women were more likely to have a CNM during birth than US-born Black women, but Haitian-born and Jamaican-born women had lower odds of having a certified professional midwife (CPM) at birth. When compared to US-born Black women, Cameroonian-born women had decreased odds of having either a CNM or CPM during birth. Findings suggest that DMN could be an indicator of cultural preferences in maternity care. There is a need for further investigation beyond DMN and comprehensive data collection methods for future research to understand the specific needs and preferences of different ethnocultural groups to improve maternity care and prevent adverse maternal health outcomes. Full article

Accurate population counts and the identification of granularity within aggregated groups are essential for informing funding formulas and health policies, an issue of global significance. Relying solely on aggregated ethnicity-based population counts has limited utility for ethnic minority groups. Accurate and relevant population counts are critical for monitoring and improving outcomes related to health, social welfare, and education. This paper examines additional dimensions of identity to provide a revised estimate of the total population count for Peoples of Fiji (PF) living in Aotearoa. Customised data tables from the Census of Population and Dwellings, provided by Statistics New Zealand, were analysed using ethnicity and additional recorded characteristics, such as country of birth, and parents’ ethnicity, to obtain more accurate counts for the major ethnic groups from Fiji living in Aotearoa. Our analysis revealed that almost 50,000 Fijian Indians were misclassified. Utilizing additional variables, we estimate the revised count for the Fijian Indian ethnic group alone exceeds 70,000 and the PF total count exceeds 2% of Aotearoa’s current population. We highlight significant variations in ethnicity coding for PF and their implications for health monitoring and risk assessment, data quality, and interpretation. We make key recommendations to improve granular reporting for minority migrant groups in Aotearoa. Full article

Partner selection is a complex process shaped by structural, social, and personal factors. For refugees and forced migrants, displacement and adaptation add further challenges, with families—even from far away—playing a crucial role in shaping expectations and influencing partnership decisions. This influence can be direct—through arranged marriages or introductions—or indirect, by setting expectations based on ethnicity, religion, or social status. Family endorsement is often crucial in reinforcing ethnic, religious, or language group continuity and community acceptance. This study examines the role of family in partner selection among refugees who arrived in Germany largely during the 2015–2016 period, a group characterized by a high proportion of unmarried men with limited family support. This group is compared to the German resident population, both with and without a migration background. For the descriptive analyses, we draw on two data sources: the PARFORM dataset, collected in 2022–2023, which covers male Syrian and Afghan refugees who arrived between 2014 and 2018; and the ninth wave of the CILS4EU-DE, collected in 2022. The multivariate analyses rely exclusively on the PARFORM dataset and utilize linear probability models with selection correction. We contribute to the literature in three key ways: identifying mechanisms of family influence despite physical distance; introducing a multidimensional framework to measure partnership outcomes based on ethnic, religious, and linguistic endogamy; and providing new insights into the underexplored partnership formation of this refugee cohort. Full article

Although the relationship between grandparent and grandchild is often unique due to the supportive and foundational roles grandparents can have in the lives of young or youthful grandchildren, the extent of grandparent–grandchild coresidence globally is under-researched. We harmonized household roster survey data on grandchild coresidence using population-based data on adults 55+ years across 24 countries. Grandchild coresidence rates ranged from 41.1% in Mexico to 0.1% in Sweden. Across contexts, grandchild coresidence was more common among women (compared to men), non-partnered individuals (compared to partnered individuals), those who reported difficulty with activities of daily living (compared to those without such difficulties), and those with education levels below the median (compared to those above the median). Logit regressions indicated gaps in rates of grandchild coresidence by partner status, ADL status, and education were generally not driven by income or other socio-demographic variables. Coresidence with adult grandchildren was not uncommon in most countries with non-negligible rates of grandchild coresidence. In about 25% of households of middle-aged and older adults coresiding with grandchildren, grandchildren ages 0–5 years were present. Future research should consider the meaning of grandparent–grandchild coresidence for the health outcomes of middle-aged and older adults globally, particularly when grandparents are not caregivers of grandchildren. Full article

Despite ongoing efforts to reduce maternal mortality in Nigeria, the uptake of skilled birth attendance remains persistently low, especially in rural areas. While structural and socio–demographic barriers have been widely studied, less attention has been paid to psychological determinants of maternal healthcare-seeking behavior in low-resource settings. This study explores how the locus of control influences the use of skilled birth care among postpartum women in rural Edo State, Nigeria, and whether neuroticism serves as a mediating factor in this relationship. We draw on data from a cross-sectional survey involving 1411 women aged 15–45 who had given birth within the two years preceding the study. Participants were recruited from 20 randomly selected communities across two rural Local Government Areas. Data were collected using structured interviews that included validated measures of locus of control, neuroticism, and self-reported use of skilled birth care. We applied the Baron and Kenny mediation framework using linear and logistic regression models with standardized coefficients, adjusting for education, household wealth, and women’s decision-making autonomy. The findings show that women with a more external locus of control were significantly less likely to utilize skilled birth care (p < 0.01), and that neuroticism partially mediated this effect. Higher levels of neuroticism were associated with a reduced likelihood of engaging with skilled maternity care services. These results highlight the importance of psychological traits in shaping maternal health behaviors. Integrating psychosocial interventions, such as emotional support, cognitive reframing, and community health education, into maternal healthcare programs may improve service uptake in marginalized rural populations. Full article

This study predicts how sociodemographic trends—smaller family sizes, increased longevity, and marital patterns—could affect family care for people with dementia through 2060. By coupling dementia information from the Health and Retirement Study with a well-established kinship microsimulation model, we analyze the impact of demographic changes on the future care landscape, focusing on changes in race and gender differences in two key areas: (1) the availability of family caregivers for people with dementia, and (2) the likelihood of having a family member with dementia, among those without dementia. Our model projections suggest that future dementia cohorts will be more likely to have a living spouse than the current ones, with diminishing gender disparities due to increased male longevity. However, racial disparities will persist, particularly for Black women. The likelihood of older adults lacking spouses, children, and siblings will increase, but remain low. For potential caregivers, we predict an increased likelihood and longer duration of exposure to family members with dementia in future birth cohorts, particularly for Black individuals, potentially placing more people at risk of the adverse health and well-being outcomes associated with caregiving. Full article

The accelerated growth of older adults (the over-65s) in Italy fits within the context of the complex, hybrid nature of the pension system and the welfare benefits financed by tax revenues, which often overlap. As a result, older adults are experiencing growing inequalities in living and health conditions across the three Italian macro-areas (the North, Centre, and South and Islands), as well as between genders. This study aims to examine the sustained growth of older adults in Italy, with a particular emphasis on their most vulnerable segment—i.e., the over-85s. Drawing on mortality trends and the consequent increases in life expectancy at advanced ages, through indicators of mortality and life expectancy, the analysis explores how variations in the structure and distribution of pension benefits have produced significant territorial disparities. These disparities have, in turn, contributed to widening inequalities in household living conditions, especially regarding access to social assistance and long-term care services. Full article

Although other studies have utilized demographic variables to characterize pet owners, this study incorporates a demographic framework that considers different family structures—couples and singles, with or without children—to better understand the place of pets within families. This article explores the extent to which pets fit into families in either substitute or complementary family roles, whether the inclusion of pets in families is subject to resource constraints or cultural proclivities. Data are from the 2023 Pew Research Social Trends study, a nationally representative telephone survey of 5073 respondents, analyzed using bivariate and multinomial models. Results indicate that couples without children are just as likely to be a dog-only household as are the traditional pet-owning families of couples with young children. They are also more likely to have cats, with or without dogs, compared to couples with young children. Homeownership makes pets, especially dogs, more feasible for families. The results suggest that pets are considered as substitutes and/or complements for other family members. Pets may be more affordable and attainable substitutes and/or complements for human family members, provided there are both human and spatial resources, filling a niche created by changes in family formation patterns, while providing affection, companionship and a sense of home. Full article

Ageing in place is the ability to remain in one’s community, where living conditions foster a sense of attachment that enhances holistic well-being. To facilitate this, both the built and social environments within which the home is nested must be conducive to successful ageing. This paper deconstructs the merits of ageing in place, specifically how attachment to the lived environment contributes to holistic well-being. We analysed data from 6020 participants in the Singapore Life Panel^® using path models, where we examined three dimensions of ageing in place: place identity, continuity, and social inclusion. Five path analyses show that two dimensions of ageing in place mediated the relationship between well-being and factors such as social isolation, number of close neighbours, social support, and satisfaction with amenities, but not living arrangements. Social inclusion consistently showed no significant relationship with well-being across all models. These findings suggest that the quality of social connections, rather than physical living arrangements, is important for well-being, and that social inclusion needs to be more appropriately contextualised. Our study contributes to policy discussions on how supporting older adults to age in place can enhance their overall well-being. Full article

The COVID-19 pandemic has widened the gap in mortality between different population groups. While socioeconomic status has been shown to be an important determinant of mortality, the relationship between migration status and mortality risk remains unclear. The objective of this paper is to explain whether and why foreign populations had a higher risk of mortality than Swiss nationals during the initial outbreak of the COVID-19 pandemic in Switzerland. We use original linked data to measure the risk of COVID-19 mortality for different groups of foreigners, compared to Swiss nationals, using logistic regression. We find that the risk of death from COVID-19 in 2020 was significantly higher for some groups of foreign nationals—but not all groups—compared to Swiss nationals. Increased mortality is observed among foreign communities who have been living in Switzerland for more than 20 years, notably, Italians, people of Balkan origin, and Latin Americans. For these three communities, we suggest that high mortality is due to a combination of overexposure, for socioeconomic reasons, and reduced access to health systems. These findings contribute to the understanding of migrant health disparities during pandemics and inform future public health interventions. Full article

I rely on the key concepts of diffusion and percolation to characterize the sequential but overlapping phases of the spread of infection through entire populations during the first year of the COVID-19 pandemic. Data from Los Angeles County demonstrate an extended initial diffusion phase propelled by radial geographic spread, followed by percolation within hotspots fueled by the presence of multigenerational households. Data from New York City, by contrast, reveal rapid initial diffusion along a unique, extensive subway network. Subsequent percolation within multiple hotspots, similarly powered by a high density of multigenerational households, exerted a positive feedback effect that further enhanced diffusion. Data from Florida counties support the generality of the phenomenon of viral transmission from more mobile, younger individuals to less mobile, older individuals. Data from the South Brooklyn hotspot reveal the limitations of some forms of government regulation in controlling mobility patterns that were critical to the continued percolation of the viral infection. Data from a COVID-19 outbreak at the University of Wisconsin—Madison demonstrate the critical role of a cluster of off-campus bars as an attractor for the continued percolation of infection. The evidence also demonstrates the efficacy of quarantine as a control strategy when the hotspot is contained and well identified. Full article

This study uses data from the 2006–2012 Health and Retirement Study (HRS) genetic sample (N = 11,667) to explore the “immigrant health paradox” from a novel perspective by examining the nativity differences in genetic predisposition to health-related outcomes. Polygenic indices (PGIs) were used to evaluate whether older non-Hispanic white foreign-born individuals have genotypes that predispose them to better health profiles compared to their U.S.-born counterparts. The results show an immigrant advantage with respect to genetic predisposition to cognitive function, BMI, and smoking frequency. There are no significant differences in genetic predisposition to height, smoking initiation, and depression. Including respective PGIs in multinomial regression models partially explains an immigrant advantage with respect to cognitive function and obesity. The findings are consistent with the “healthy immigrant effect” or selective migration of individuals with a favorable genetic predisposition to health as one of the explanations of the immigrant health paradox. Full article