Zaneta M. Thayer

Assessment of acculturation in minority health research.

Acculturation represents an important construct in the context of health disparities. Although several studies have reported relationships between various aspects of acculturation and health in minority populations, crucial inconsistencies remain. One likely reason for these inconsistencies may relate to limitations in the conceptualization and operationalization of acculturation, particularly in the context of health research. The acculturation construct underwent major conceptual and operational change when it was adapted from anthropology to psychology, and we argue another major shift is now required for use of this construct in health research. Issues include determining whether acculturation measures should focus on an individuals internal attitudes or overt behaviors; whether they should characterize cultural orientation status at a given point in time or change over time; whether measures should be culture-specific or more global in nature; how the issue of multiculturalism should be addressed; how measures can optimally incorporate multiple dimensions of acculturation; and whether proxy measures should be used. These issues are important in the context of health research because of their implications for determining the direct and indirect effects of cultural change on health-related biological and behavioral processes. We elaborate on and address each of these issues from a perspective that spans multiple disciplines across the biological and social sciences, and offer concrete recommendations with the ultimate goal of achieving a better understanding of the role of acculturation in minority health and health disparities.

Early life trauma, post‐traumatic stress disorder, and allostatic load in a sample of American Indian adults

Among American Indians, prior research has found associations between early life trauma and the development of post‐traumatic stress disorder (PTSD) in adulthood. Given the physiological changes associated with PTSD, early life trauma could indirectly contribute to chronic disease risk. However, the impact of early life trauma on adult physical health in this population has not been previously investigated.

Acculturation and Health: The Moderating Role of Sociocultural Context

Acculturation represents an important construct for elucidating the determinants and consequences of health disparities in minority populations. However, the processes and mechanisms underlying acculturations effects on health are largely undetermined and warrant further study. We integrate concepts from anthropology and statistics to describe the role of sociocultural context as a putative modifier of the relationship between acculturation and health. Sociocultural context may influence the extent to which exposure to host culture leads to internalization of host cultural orientation, and may influence the extent to which acculturation leads to stress and adoption of unhealthy behaviors. We focus on specific aspects of sociocultural context: (1) neighborhood ethno-cultural composition; (2) discrimination; (3) discrepancy between origin and host environments; (4) discrepancy between heritage and host cultures; (5) origin group, host group, and individual attitudes towards assimilation; (6) variation in targets of assimilation within host community; (7) public policy and resources; (8) migration selection bias. We review and synthesize evidence for these moderation effects among first- and later-generation immigrants, refugees, and indigenous populations. Furthermore, we propose best-practices data-collection and statistical-analysis methods for this purpose, in order to improve our understanding of the complex, multilevel aspects of the relationship between acculturation and health.

Impact of prenatal stress on offspring glucocorticoid levels: A phylogenetic meta-analysis across 14 vertebrate species

Prenatal exposure to maternal stress is commonly associated with variation in Hypothalamic Pituitary Adrenal (HPA)-axis functioning in offspring. However, the strength or consistency of this response has never been empirically evaluated across vertebrate species. Here we meta-analyzed 114 results from 39 studies across 14 vertebrate species using Bayesian phylogenetic mixed-effects models. We found a positive overall effect of prenatal stress on offspring glucocorticoids (d’u2009=u20090.43) though the 95% Highest Posterior Density Interval overlapped with 0 (−0.16–0.95). Meta-regressions of potential moderators highlighted that phylogeny and life history variables predicted relatively little variation in effect size. Experimental studies (d’u2009=u20090.64) produced stronger effects than observational ones (d’u2009=u2009−0.01), while prenatal stress affected glucocorticoid recovery following offspring stress exposure more strongly (d’u2009=u20090.75) than baseline levels (d’u2009=u20090.48) or glucocorticoid peak response (d’u2009=u20090.36). These findings are consistent with the argument that HPA-axis sensitivity to prenatal stress is evolutionarily ancient and occurs regardless of a species’ overall life history strategy. These effects may therefore be especially important for mediating intra-specific life-history variation. In addition, these findings suggest that animal models of prenatal HPA-axis programming may be appropriate for studying similar effects in humans.

Maternal salivary cortisone to cortisol ratio in late pregnancy: An improved method for predicting offspring birth weight

Overexposure to maternal cortisol in utero has been associated with lower birth weight of offspring. In order to regulate fetal exposure to this hormone, placental expression of 11-β-hydroxysteroid dehydrogenase-2, an enzyme that converts active cortisol to inactive cortisone, increases across pregnancy. Because of this increase in 11-βHSD2 activity, measuring maternal cortisol in isolation may not reflect actual fetal exposure to the hormone. Previous work by Hellgren et al. (2016) has shown that maternal serum cortisone:cortisol ratio was a better predictor of offspring birth weight than cortisol measured in isolation. This paper sought to replicate these results when examining maternal salivary cortisone:cortisol ratio. Data come from 55 pregnant women from Auckland, New Zealand. Cortisol and cortisone were measured in saliva samples collected at waking and prior to going to sleep on two consecutive weekdays between 34 and 36 weeks of gestation. We found that salivary cortisol and cortisone followed the expected diurnal rhythm and that cortisone was higher than cortisol at both times of day. Maternal bedtime cortisone:cortisol ratio was significantly and inversely related to offspring birth weight. However, waking and bedtime cortisol, as well as waking cortisone:cortisol ratio, were unrelated to birth weight. These results show that maternal salivary cortisone:cortisol ratio, like serum cortisone:cortisol ratio, is a more sensitive biomarker for predicting infant birth weight than cortisol measured in isolation. This ratio could be a valuable, minimally-invasive measurement for future studies interested in understanding the relationship between maternal HPA-axis function and offspring birth weight.

Racial discrimination associated with higher diastolic blood pressure in a sample of American Indian adults: THAYER et al.

OBJECTIVESnHypertension prevalence is high among American Indians (AIs). AIs experience a substantial burden of interpersonal racial discrimination, which in other populations has been associated with higher blood pressure. The purpose of this study is to understand whether racial discrimination experiences are associated with higher blood pressure in AIs.nnnMATERIALS AND METHODSnWe used the Everyday Discrimination Scale to evaluate the relationship between discrimination and measured blood pressure among 77 AIs from two reservation communities in the Northern Plains. We used multivariate linear regression to evaluate the association of racial discrimination with systolic and diastolic blood pressure, respectively. Racial discrimination, systolic blood pressure, and diastolic blood pressure were analyzed as continuous variables. All analyses adjusted for sex, waist circumference, age, posttraumatic stress disorder status, and education.nnnRESULTSnWe found that 61% of participants experienced discrimination that they attributed to their race or ancestry. Racial discrimination was associated with significantly higher diastolic blood pressure (βu2009=u20090.22, SEu2009=u20090.09, pu2009=u2009.02), and with a similar non-significant trend toward higher systolic blood pressure (βu2009=u20090.25, SEu2009=u20090.15, pu2009=u2009.09).nnnCONCLUSIONnThe results of this analysis suggest that racial discrimination may contribute to higher diastolic blood pressure within Native communities. These findings highlight one pathway through which the social environment can shape patterns of biology and health in AI and other socially and politically marginalized groups.

The relationship of five boarding school experiences and physical health status among Northern Plains Tribes

PurposeAmerican Indian (AI) boarding school attendance is related to poor physical health status; however, little is known about how specific aspects of this experience contribute to poor health. Five experiences (age of first attendance, limited family visits, forced church attendance, prohibition on practicing AI culture and traditions, and punishment for use of AI language) may be independently associated with physical health status in adulthood. We expected the effect to be greater for those who began boarding school at older ages.MethodsData on AI boarding school attenders (nu2009=u2009771) came from the AI-Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project. Multiple linear regression models examined the association of these five experiences with physical health status. Additionally, we conducted a separate set of regressions to test for an interaction effect of age of first attendance.ResultsEach of the five experiences noted above were independently associated with poorer physical health status compared to those who did not have these experiences. An interaction effect for those punished for use of AI language and who were aged 8 or older was confirmed.ConclusionsFindings are consistent with reports that boarding school attendance is related to poor AI adult health. To inform AI health programs, the relationship of specific diseases and boarding school attendance should be considered.

Exploring the timing and duration of maternal stress exposure: Impacts on early childhood BMI

• Stress exposure, in both the pre-and post-natal periods, is positively associated with early childhood BMI.

Impact of acculturation on depression, perceived stress and self-esteem in young Middle Eastern American adults

Abstract Background: Human biologists have a longstanding interest in understanding the biological and health impacts of migration. Acculturation, the cultural adjustment that a group or individual experiences when previously separate cultures interact, has been found to be one pathway through which migration may impact human biology and health, not only for the migrants themselves, but also their descendants. Aim: The authors conducted a pilot study to examine the relationship between acculturation and perceived stress, self-esteem and depression among young Middle-Eastern American adults. Subject and methods: Survey data were collected from 48 young Middle-Eastern American adults. Participants were divided into one of two acculturation categories, integrated (American and Middle Eastern culture oriented) and assimilated (American culture oriented). Health measures were compared between these acculturation categories. Results: Integrated individuals had significantly lower stress (Fu2009=u20098.1, pu2009<u20090.01) and depression (Fu2009=u200910.8, pu2009<u20090.01) than assimilated individuals. Integrated individuals had lower self-esteem than assimilated individuals (Fu2009=u20095.0, pu2009<u20090.05). Generational status, a proxy used for acculturation, was only significantly associated with self-esteem (Fu2009=u20093.15, pu2009=u20090.05). Conclusion: This pilot study furthers understanding of the effects acculturation can have on perceived stress and mental health among young Middle-Eastern Americans. Future research should incorporate biological measures of stress to determine the physiological impacts of acculturation.

Prenatal stress exposure and early childhood BMI: Exploring associations in a New Zealand context

The primary purpose of this study was to (i) examine associations between prenatal objective vulnerability and subjective stress, and (ii) investigate the relationships between prenatal vulnerability and subjective stress and early childhood BMI at 24‐ and 54‐ months of age after controlling for covariates.