Social Determinant Pathways to Hypertensive Disorders of Pregnancy Among Nulliparous U.S. Women.

BACKGROUND: Hypertensive disorders of pregnancy are a leading cause of maternal morbidity and mortality in the United States and impact Black mothers at disproportionately higher rates. Hypertensive disparities among racialized groups are rooted in systemic inequalities, and we hypothesize that clinical markers of allostatic load capture embodied disparities in stressors that can link upstream social determinants of health with downstream hypertensive outcomes. METHODS: We analyzed observational cohort data from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (n = 6,501) and developed a structural equation model linking latent social determinants of health, longitudinal markers of allostatic load across gestation, and hypertensive pregnancy outcomes in a multigroup framework. RESULTS: Non-Hispanic Black mothers-to-be (n = 1,155) showed higher rates of hypertensive disorders of pregnancy (32%) than non-Hispanic white women (n = 5,346, 23%). Among both groups, the social environment showed stronger direct effects on allostatic markers than via behaviorally mediated dietary, exercise, or smoking pathways. Demographic aspects of the social environment (e.g., household income, partnered status) were the most salient predictor of hypertensive risk and showed stronger effects among Black women. CONCLUSIONS: Embodied stress rooted in the social environment is a major path driving maternal hypertensive disparities in the United States, with effects that vary across racialized groups. These pathway findings underscore the greater impact of systemic stressors relative to individual health behaviors. More comprehensive and detailed analyses of sociostructural domains are needed to identify promising avenues for policy and intervention to improve maternal health.

Economic impacts and nutritional outcomes of the 2017 floods in Bangladeshi Shodagor fishing families.

OBJECTIVES: As climate change continues to increase the frequency and severity of flooding in Bangladesh and globally, it becomes increasingly critical to understand the pathways through which flooding influences health outcomes, particularly in lower-income and subsistence-based communities. We aim to assess economic pathways that link flooding to nutritional outcomes among Shodagor fishing families in Bangladesh. METHODS: We examine longitudinal economic data on kilograms of fish caught, the income earned from those fish, and household food expenditures (as a proxy for dietary intake) from before, during, and after severe flooding in August-September of 2017 to enumerate the impacts of flooding on Shodagor economics and nutrition. We also analyze seasonally collected anthropometric data to model the effects of flooding and household food expenditures on child growth rates and changes to adult body size. RESULTS: While Shodagor fishing income declined during the 2017 flooding, food expenditures simultaneously spiked with market inflation, and rice became the predominant expenditure only during and immediately following the flood. Our nutritional models show that children and adults lost more body mass in households that spent more money on rice during the flood. Shodagor children lost an average of 0.36 BMI-for-age z-scores and adults lost an average of 0.32 BMI units during the flooded 2017 rainy season, and these metrics continued to decline across subsequent seasons and did not recover by the end of the study period in 2019. CONCLUSIONS: These results show major flood-induced economic impacts that contributed to loss of child and adult body mass among Shodagor fishing families in Bangladesh. More frequent and severe flooding will exacerbate these nutritional insults, and more work is needed to effectively stabilize household nutrition throughout natural disasters and economic hardship.

SARS-CoV-2 specific antibody trajectories in mothers and infants over two months following maternal infection.

Infants exposed to caregivers infected with SARS-CoV-2 may have heightened infection risks relative to older children due to their more intensive care and feeding needs. However, there has been limited research on COVID-19 outcomes in exposed infants beyond the neonatal period. Between June 2020 - March 2021, we conducted interviews and collected capillary dried blood spots from 46 SARS-CoV-2 infected mothers and their infants (aged 1-36 months) for up to two months following maternal infection onset (COVID+ group, 87% breastfeeding). Comparative data were also collected from 26 breastfeeding mothers with no known SARS-CoV-2 infection or exposures (breastfeeding control group), and 11 mothers who tested SARS-CoV-2 negative after experiencing symptoms or close contact exposure (COVID- group, 73% breastfeeding). Dried blood spots were assayed for anti-SARS-CoV-2 S-RBD IgG and IgA positivity and anti-SARS-CoV-2 S1 + S2 IgG concentrations. Within the COVID+ group, the mean probability of seropositivity among infant samples was lower than that of corresponding maternal samples (0.54 and 0.87, respectively, for IgG; 0.33 and 0.85, respectively, for IgA), with likelihood of infant infection positively associated with the number of maternal symptoms and other household infections reported. COVID+ mothers reported a lower incidence of COVID-19 symptoms among their infants as compared to themselves and other household adults, and infants had similar PCR positivity rates as other household children. No samples returned by COVID- mothers or their infants tested antibody positive. Among the breastfeeding control group, 44% of mothers but none of their infants tested antibody positive in at least one sample. Results support previous research demonstrating minimal risks to infants following maternal COVID-19 infection, including for breastfeeding infants.

Cesarean section and breastfeeding outcomes in an Indigenous Qom community with high breastfeeding support.

BACKGROUND AND OBJECTIVES: Cesarean section may lead to suboptimal breastfeeding outcomes, though evidence has been mixed. Factors, such as premature birth, birth weight and maternal age may independently increase risk of cesarean and hinder breastfeeding initiation, while maternal preferences, support and sociostructural barriers may influence breastfeeding practices beyond the immediate postpartum period. METHODOLOGY: We assessed impacts of cesarean section and gestational factors on breastfeeding duration among Indigenous Qom mothers in Argentina who have strong traditional breastfeeding support. We modeled transitions from exclusive breastfeeding to complementary feeding and from complementary feeding to full weaning in a Bayesian time-to-event framework with birth mode and gestational covariates (n = 89 infants). RESULTS: Estimated median time to full weaning was 30 months. Cesarean-delivered babies were weaned an average of 5 months later adjusting for gestational age, maternal parity and infant sex. No factors were associated with time-to-complementary feeding, and time-to-complementary feeding was not associated with time-to-full weaning. CONCLUSIONS AND IMPLICATIONS: Among Indigenous Qom mothers in Argentina, cesarean section was not associated with suboptimal breastfeeding outcomes. Although some Qom mothers do experience early breastfeeding problems, particularly following first birth, problems are not more frequent following cesarean delivery. Traditional postpartum kin and community support during prolonged postpartum periods may be instrumental in helping mothers to overcome early breastfeeding problems due to cesarean or other risk factors.

Genetic ancestry, admixture, and population structure in rural Dominica.

The Caribbean is a genetically diverse region with heterogeneous admixture compositions influenced by local island ecologies, migrations, colonial conflicts, and demographic histories. The Commonwealth of Dominica is a mountainous island in the Lesser Antilles historically known to harbor communities with unique patterns of migration, mixture, and isolation. This community-based population genetic study adds biological evidence to inform post-colonial narrative histories in a Dominican horticultural village. High density single nucleotide polymorphism data paired with a previously compiled genealogy provide the first genome-wide insights on genetic ancestry and population structure in Dominica. We assessed family-based clustering, inferred global ancestry, and dated recent admixture by implementing the fastSTRUCTURE clustering algorithm, modeling graph-based migration with TreeMix, assessing patterns of linkage disequilibrium decay with ALDER, and visualizing data from Dominica with Human Genome Diversity Panel references. These analyses distinguish family-based genetic structure from variation in African, European, and indigenous Amerindian admixture proportions, and analyses of linkage disequilibrium decay estimate admixture dates 5-6 generations (~160 years) ago. African ancestry accounts for the largest mixture components, followed by European and then indigenous components; however, our global ancestry inferences are consistent with previous mitochondrial, Y chromosome, and ancestry marker data from Dominica that show uniquely higher proportions of indigenous ancestry and lower proportions of African ancestry relative to known admixture in other French- and English-speaking Caribbean islands. Our genetic results support local narratives about the community's history and founding, which indicate that newly emancipated people settled in the steep, dense vegetation along Dominica's eastern coast in the mid-19th century. Strong genetic signals of post-colonial admixture and family-based structure highlight the localized impacts of colonial forces and island ecologies in this region, and more data from other groups are needed to more broadly inform on Dominica's complex history and present diversity.

Serial Diffusion Kurtosis Magnetic Resonance Imaging Study during Acute, Subacute, and Recovery Periods after Sport-Related Concussion.

Sport-related concussion (SRC) is common in contact sports, but there remains a lack of reliable, unbiased biomarkers of brain injury and recovery. Although the symptoms of SRC generally resolve over a period of days to weeks, the lack of a biomarker impairs detection and return-to-play decisions. To this date, the pathophysiological recovery profile and relationships between brain changes and symptoms remained unclear. In the current study, diffusion kurtosis imaging (DKI) was used to monitor the effects of SRC on the brain and the trajectory of recovery in concussed American football players (n = 96) at <48 h, and 8, 15, and 45 days post-injury, who were compared with a matched group of uninjured players (n = 82). The concussed group reported significantly higher symptoms within 48 h after injury than controls, which resolved by the 8-day follow-up. The concussed group also demonstrated poorer performance on balance testing at <48 h and 8 days than controls. There were no significant differences between the groups in the Standardized Assessment of Concussion (SAC), a cognitive screening measure. DKI data were acquired with 3 mm isotropic resolution, and analyzed using tract-based spatial statistics (TBSS). Additionally, voxel- and region of interest-based analyses were also conducted. At <48 h, the concussed group showed significantly higher axial kurtosis than the control group. These differences increased in extent and magnitude at 8 days, then receded at 15 days, and returned to the normal levels by 45 days. Kurtosis fractional anisotropy (FA) exhibited a delayed response, with a consistent increase by days 15 and 45. The results indicate that changes detected in the acute period appear to be prolonged compared with clinical recovery, but additional brain changes not observable acutely appear to progress. Although further studies are needed to understand the pathological features of DKI changes after SRC, these findings highlight a potential disparity between clinical symptoms and pathophysiological recovery after SRC.

Anthropometric heritability and child growth in a Caribbean village: A quantitative genetic analysis of longitudinal height, weight, and body mass index in Bwa Mawego, Dominica.

OBJECTIVES: Body size and composition vary widely among individuals and populations, and long-term research in diverse contexts informs our understanding of genetic, cultural, and environmental impacts on this variation. We analyze longitudinal measures of height, weight, and body mass index (BMI) from a Caribbean village, estimating the extent to which these anthropometrics are shaped by genetic variance in a small-scale population of mixed ancestry. MATERIALS AND METHODS: Longitudinal data from a traditionally horticultural village in Dominica document height and weight in a non-Western population that is transitioning to increasingly Westernized lifestyles, and an 11-generation pedigree enables us to estimate the proportions of phenotypic variation in height, weight, and BMI attributed to genetic variation. We assess within-individual variation across growth curves as well as heritabilities of these traits for 260 individuals using Bayesian variance component estimation. RESULTS: Age, sex, and secular trends account for the majority of anthropometric variation in these longitudinal data. Independent of age, sex, and secular trends, our analyses show high repeatabilities for the remaining variation in height, weight, and BMI growth curves (>0.75), and moderate heritabilities (h2height = 0.68, h2weight = 0.64, h2BMI = 0.49) reveal clear genetic signals that account for large proportions of the variation in body size observed between families. Secular trends show increases of 6.5% in height and 16.0% in weight from 1997 to 2017. DISCUSSION: This horticultural Caribbean population has transitioned to include more Westernized foods and technologies over the decades captured in this analysis. BMI varies widely between individuals and is significantly shaped by genetic variation, warranting future exploration with other physiological correlates and associated genetic variants.

One piece of the matrilineal puzzle: the socioecology of maternal uncle investment.

Maternal uncle relationships in which men invest resources (usually in the form of inheritance of material wealth) into their sisters' children are characteristic of matrilineal systems and hypothesized to arise under certain socioecological circumstances, but little research has systematically investigated conditions that are associated with this type of investment. We quantify relationships between household-level socioeconomic variables and different types of maternal uncle investment (direct care and indirect resource investment) within a bilateral, semi-nomadic population. Shodagor people of Bangladesh allow us to consider matrilineal behaviours in an evolutionary framework owing to their flexible social structure in which 39% of families receive some investment from a maternal uncle. Variables associated with direct maternal uncle care reflect the significance of maintaining consistent residence throughout the year and an increased need for childcare in families residing on boats versus those living on the land. Informative predictors of indirect investment indicate that a mother's birth history corresponds with more tangible contributions such as food and clothing. These results identify household-level variables specific to direct versus indirect maternal uncle investment, whereas having more older brothers or being firstborn increased the odds of a mother receiving any investment from brothers at all. Exploring these social and ecological associations in a bilateral, relatively flexible population unveils household circumstances that may lead to the development of female-biased kinship. This article is part of the theme issue 'The evolution of female-biased kinship in humans and other mammals'.

Estimating impacts of the nuclear family and heritability of nutritional outcomes in a boat-dwelling community.

OBJECTIVES: General health status is reflected in measures of height, weight, and BMI. Assessing sources of variation in these outcomes reveals population-specific variables of importance to health and nutrition. We characterize the impacts of socioeconomic variables related to the nuclear family on health outcomes of boat-dwelling Shodagor children, mothers, and fathers, and to estimate the proportion of variation in height, weight, and BMI influenced by both genetic variation and nongenetic variation among household environments. METHODS: Bayesian linear mixed models (LMMs) estimate heritability and household-effect variance components among the Shodagor. These models also assess the influences of specific socioeconomic predictor variables on different types of individuals within the household (children, mothers, and fathers). RESULTS: Overall, models explain 61.7% of variation in height, 59.4% in weight, and 65.8% in BMI for this sample of Shodagor. Mother's decision-making and household income have expected, positive associations with children's weight and BMI. Number of children has an unexpected positive relationship to children's height and a negative relationship to father's BMI. Genetic variation explains less than 26% of phenotypic variation for each of these traits on average. CONCLUSIONS: Our results show that resource flows and distributions within Shodagor households account for a significant amount of variance in nutritional outcomes. Problems commonly associated with increasing market integration may lead to negative outcomes for children, while mother's autonomy may lead to positive outcomes. Our models also indicate that environmental factors account for more variation in these outcomes than expected, relative to genetics, and we discuss the implications.

Cold acid elution (ELU Kit II).

Elution is a procedure for recovery of antibody attached to intact,immunoglobulin-coated red blood cells (RBCs) by disrupting the antigen-antibody bonds. The recovered antibody is collected in an inert diluent and is referred to as an eluate. Testing of an eluate may be desired to identify antibody(ies) coating the RBCs of patients with a positive direct antiglobulin test. Many types of elution procedures have been developed and described; however,·an acid elution is suitable for antibody recovery in most cases, such as recovery of alloantibodies and warm-reactive autoantibodies.Studies have compared methods such as xylene, chloroform, digitnin acid, dichloromethane, citric acid, and Immucor Elu-KitII (cold acid elution). The ELU-Kit II has been shown to be quick and effective at eluting a wide range of alloantibodies as well as autoantibodies without the use of hazardous chemicals or costly reagent preparation time that some methods use. It is for these reasons that the ELU-Kit II is a very popular method for the elution of immunoglobulin G (IgG) antibodies.