Concurrent Social Disadvantages and Chronic Inflammation: The Intersection of Race and Ethnicity, Gender, and Socioeconomic Status

Pain mechanisms in the transgender individual: a review

Specific Aim

Provide an overview of the literature addressing major areas pertinent to pain in transgender persons and to identify areas of primary relevance for future research.

Methods

A team of scholars that have previously published on different areas of related research met periodically though zoom conferencing between April 2021 and February 2023 to discuss relevant literature with the goal of providing an overview on the incidence, phenotype, and mechanisms of pain in transgender patients. Review sections were written after gathering information from systematic literature searches of published or publicly available electronic literature to be compiled for publication as part of a topical series on gender and pain in the Frontiers in Pain Research.

Results

While transgender individuals represent a significant and increasingly visible component of the population, many researchers and clinicians are not well informed about the diversity in gender identity, physiology, hormonal status, and gender-affirming medical procedures utilized by transgender and other gender diverse patients. Transgender and cisgender people present with many of the same medical concerns, but research and treatment of these medical needs must reflect an appreciation of how differences in sex, gender, gender-affirming medical procedures, and minoritized status impact pain.

Conclusions

While significant advances have occurred in our appreciation of pain, the review indicates the need to support more targeted research on treatment and prevention of pain in transgender individuals. This is particularly relevant both for gender-affirming medical interventions and related medical care. Of particular importance is the need for large long-term follow-up studies to ascertain best practices for such procedures. A multi-disciplinary approach with personalized interventions is of particular importance to move forward.

BMI, socioeconomic status, and bone mineral density in U.S. adults: Mediation analysis in the NHANES

Introduction

The mechanism by which socioeconomic status (SES) affects bone mineral density (BMD) remains unknown, and body mass index (BMI) may be a potential mediator. The purpose of this study was to investigate whether BMI mediates the relationship between SES [education level and poverty income ratio (PIR)] and lumbar BMD and the proportion it mediates.

Methods

This study included a total of 11,075 adults from the National Health and Nutrition Examination Survey (NHANES). Lumbar BMD was measured at the lumbar spine by dual-energy X-ray absorptiometry (DXA). Multivariate linear regression and smoothing curve fitting were used to investigate the relationship between SES and lumbar BMD. Mediator analysis was used to investigate the proportion of BMI mediating the association between SES and BMD.

Results

In the fully adjusted model, there was a positive correlation between SES and BMD (education level: β = 0.025, 95% CI: 0.005, 0.045; PIR: β = 0.007, 95% CI: 0.002, 0.011). Mediation analysis showed that BMI mediated the relationship between PIR, education level, and lumbar BMD with a range of mediation proportions from 13.33 to 18.20%.

Conclusion

BMI partially mediated the positive association between SES and BMD, and this association may be largely mediated by factors other than BMI.

Disparities in inflammation between non-Hispanic black and white individuals with lung cancer in the Greater Chicago Metropolitan area

Background

Lung cancer incidence and mortality rates are higher in Non-Hispanic Black (NHB) compared to Non-Hispanic White (NHW) individuals in the Chicago metropolitan area, which may be related to exposure to chronic stress which may increase inflammation.

Specific aim

We investigated disparities in inflammation as measured by neutrophil to lymphocyte ratio (NLR) in individuals with lung cancer by race and by neighborhood concentrated disadvantage index (CDI).

Methods

This retrospective, cross-sectional study included 263 NHB and NHW adults with lung cancer. We analyzed NLR as a continuous and categorical variable to determine degree and prevalence of inflammation. We used Mann Whitney U, t-tests, Chi square tests, linear and logistic regression models as appropriate.

Results

More than 60% of subjects had inflammation (NLR ≥ 3) at lung cancer diagnosis. The degree of inflammation was significantly lower in NHB (NLR 5.50 +/- 7.45) compared to NHW individuals (NLR 6.53 +/- 6.53; p=0.01) but did not differ by neighborhood CDI. The prevalence of inflammation (NLR ≥ 3) was significantly lower in NHB (55.07%) compared to NHW individuals (71.20%; p<0.01) and in those from the most disadvantaged (54.07%) compared to the least disadvantaged (71.88%; p<0.01) neighborhoods.

Conclusion

At lung cancer diagnosis, there is a lower degree and prevalence of inflammation in NHB compared to NHW individuals, and lower prevalence in those residing in the most disadvantaged neighborhoods. Further research is needed to determine mechanisms of inflammation that may be contributing to lung cancer disparities as well as whether NLR is an appropriate biomarker when examining racial differences in inflammation.

The role of inflammatory markers and cortisol in the association between early social cognition abilities and later internalising or externalising problems: Evidence from a UK birth cohort

OBJECTIVE

Deficits in social cognition are associated with internalising (emotional and peer problems) and externalising (conduct problems and hyperactivity/inattention) symptoms in youth. It has been suggested that stress may be one of the mechanisms underlying these associations. However, no empirical studies have investigated if physiological stress can explain the prospective associations between social cognition deficits and internalising and externalising symptoms in the general youth population. This study addressed this question and focused on two indicators of physiological stress, dysregulated diurnal cortisol patterns and systemic inflammation.

METHOD

Participants were 714 individuals from the Avon Longitudinal Study of Parents and Children (ALSPAC), a UK population-based birth cohort. Bayesian structural equation modelling was used to investigate a) the associations of social cognition abilities at ages 8, 11, and 14 years with internalising and externalising problems at age 17 years and b) the potential mediating effects of cortisol parameters at age 15 years and inflammatory markers [interleukin 6 (IL-6) and C-reactive protein (CRP)] at ages 9 and 16 years.

RESULTS

We found that social cognition difficulties were associated with later internalising and externalising problems. Flattened diurnal cortisol slope was associated with hyperactivity/inattention problems two years later. Lower morning cortisol partially mediated the direct association between social communication deficits at 8 years and hyperactivity/inattention and conduct problems at 17 years, even after adjustments for inflammation and confounders (for hyperactivity/inattention: indirect effect = 0.07, 95% CI [0.00, 0.18], p = .042; for conduct problems: indirect effect = 0.04, 95% CI [0.00, 0.11], p = .040). We did not find a significant association between systemic inflammation and social cognition difficulties, internalising problems, or externalising problems.

CONCLUSION

Our findings suggest that part of the effect of social communication difficulties in childhood on externalising problems in adolescence was mediated by lower morning cortisol. Hence, our study indicates that the hypoactivity of the hypothalamic-pituitary-adrenal (HPA) axis may be one of the physiological mechanisms linking some social cognition deficits to externalising problems.

The Effect of Adverse Mental Health and Resilience on Perceived Stress by Sexual Violence History

Sexual violence, including nonconsensual sexual initiation and rape, remains pervasive, with impacts including adverse mental health and dysregulated stress response. Resilience is a promising interventional target. To advance the science, we examined the potential for resilience as an interventional tool by estimating associations between resilience, adverse mental health, and perceived stress among women by sexual violence history and partner perpetration. We analyzed 2018−2020 baseline survey data from 65 women enrolled in a prospective case-control study of sexual violence and HIV susceptibility in San Diego, CA. Multiple linear regressions were performed to examine associations, stratified by sexual violence history. About half of women experienced nonconsensual sexual initiation and/or rape; half of rapes were partner-perpetrated. Post-traumatic stress disorder (PTSD) was significantly associated with perceived stress among survivors (in regressions with depression and resilience, nonconsensual initiation: β = 6.514, p = 0.003, R2 = 0.616; rape: β = 5.075, p = 0.030, R2 = 0.611). Resilience was associated with lower perceived stress for all women; the effect appeared stronger among survivors of sexual violence (nonconsensual initiation: β = −0.599, p < 0.001 vs. β = −0.452, p = 0.019; rape: β = −0.624, p < 0.001 vs. β = −0.421, p = 0.027). Partner perpetration of rape was not associated with perceived stress. Our findings support leveraging resilience and addressing PTSD to reduce perceived stress among women with lifetime experiences of sexual violence.

Interrogating Patterns of Cancer Disparities by Expanding the Social Determinants of Health Framework to Include Biological Pathways of Social Experiences

The objective of this article is to call for integrating biological pathways of social experiences in the concept model of cancer disparities and social determinants of health (SDH) fields. Black, Indigenous, and People of Color (BIPOC) populations experience more negative outcomes across the cancer continuum. Social conditions are instrumental in better understanding the contemporary and historical constructs that create these patterns of disparities. There is an equally important body of evidence that points to the ways that social conditions shape biological pathways. To date, these areas of research are, for the most part, separate. This paper calls for a bridging of these two areas of research to create new directions for the field of cancer disparities. We discuss inflammation, epigenetic changes, co-morbidities, and early onset as examples of the biological consequences of social conditions that BIPOC populations experience throughout their lifespan that may contribute to disproportionate tumorigenesis and tumor progression.

The intersection of race and socioeconomic status is associated with inflammation patterns during pregnancy and adverse pregnancy outcomes

BACKGROUND

Preterm birth rates are higher among individuals of lower socioeconomic status and non-White race, which is possibly related to life-course stressors. It is important to better understand the underlying mechanisms of these health disparities, and inflammation is a possible pathway to explain the disparities in birth outcomes.

OBJECTIVE

In this study, we aimed to determine whether patterns of inflammation differed by maternal race and socioeconomic status.

STUDY DESIGN

744 participants in a multi-site, prospective study of pregnancy and birth outcomes provided biological and psychological data between 12'0-20'6 weeks gestation. Participants with recent infection, fever, antibiotics or steroid treatment were excluded. Cytokines including INFɣ, IL-10, IL-13, IL-6, IL-8, and TNFα, and the acute phase protein CRP were measured in serum and values and were log-transformed for normality when appropriate and a non-orthogonal rotation (Oblimid) was performed to allow the extracted factor to inter-correlate. IFNγ, IL-8, IL-10, IL-6, TNF-a, and IL-13 loaded onto Inflammatory Factor 1 (IF-1), while CRP and IL-6 loaded onto Inflammatory Factor 2 (IF-2). Race and education were collected via self-report during an in-person study visit. Multivariable models were used to determine the association of race and SES with IF-1 and IF-2 during the second trimester, and a mediation model to examine if inflammation is on the causal pathway. Models were adjusted for study site, prenatal age, pre-pregnancy BMI, smoking during pregnancy, and gestational age at the time of blood collection.

RESULTS

605 participants were included in our final analysis, with 61.2 % of low or moderate SES, and 35.5% identifying as a person of color (POC). Identifying as a POC, being of low and moderate SES, and being both low-SES and POC or Moderate-SES and POC were associated with higher odds of preterm birth and lower birth weight percentile infants. Low SES POC participants had significantly higher IF-1 and IF-2 scores when compared to high-SES White participants. Additionally, higher IF-1and IF-2 were associated with shorter gestation. In the mediation analysis, we observed a significant direct effect of race/SES on preterm birth, however the results did not support an indirect pathway where IF-1 or IF-2 acted as mediators.

CONCLUSION

Maternal race and SES are significantly associated with inflammatory biomarkers during pregnancy, and when race and SES are considered in combination, they are stronger predictors of adverse pregnancy outcomes than when evaluated separately. This article is protected by copyright. All rights reserved.

Systemic inflammation as a driver of health disparities among sexually-diverse and gender-diverse individuals

Sexually-diverse individuals (those who seek sexual or romantic relationships with the same and/or multiple genders) and gender-diverse individuals (those whose gender identity and/or expression differs from their birth-assigned sex/gender) have disproportionately high physical health problems, but the underlying biological causes for these health disparities remain unclear. Building on the minority stress model linking social stigmatization to health outcomes, we argue that systemic inflammation (the body's primary response to both physical and psychological threats, indicated by inflammatory markers such as C-reactive protein and proinflammatory cytokines) is a primary biobehavioral pathway linking sexual and gender stigma to physical health outcomes. Expectations and experiences of social threat (i.e., rejection, shame, and isolation) are widespread and chronic among sexually-diverse and gender-diverse individuals, and social threats are particularly potent drivers of inflammation. We review research suggesting that framing "minority stress" in terms of social safety versus threat, and attending specifically to the inflammatory consequences of these experiences, can advance our understanding of the biobehavioral consequences of sexual and gender stigma and can promote the development of health promoting interventions for this population.

Intersectionality in quantitative health disparities research: A systematic review of challenges and limitations in empirical studies

RATIONALE

Quantitative health disparities research has increasingly employed intersectionality as a theoretical tool to investigate how social characteristics intersect to generate health inequality. Yet, intersectionality was not designed to quantify, predict, or identify health disparities, and, as a result, multiple criticisms against its misapplication in health disparities research have been made. As such, there is an emerging need to evaluate the growing body of quantitative research that aims to investigate health disparities through an intersectional lens.

METHODS

We conducted a systematic review from earliest records to January 2020 to (i) describe the scope of limitations when applying intersectionality to quantitative health disparities research, and (ii) identify recommendations to improve the future integration of intersectionality with this scholarship. We identified relevant publications with electronic searches in PubMed and CA Web of Science. Studies eligible for inclusion were English-language publications that used quantitative methodologies to investigate health disparities among adults in the U.S. while explicitly claiming to adopt an intersectional perspective. Out of 1279 articles reviewed, 65 were eligible for inclusion.

RESULTS

Our review found that, while the value of intersectionality to the study of health disparities is evident, the existing research struggles with meeting intersectionality's fundamental assumptions. In particular, four limitations were found to be widespread: narrowing the measurements of intersectionality, intersectional groups, and health outcomes; placing primacy on the study of certain intersectional groups to the neglect of others; overlooking underlying explanatory mechanisms that contribute to the health disparities experienced by intersectional groups; and, lacking in the use of life-course perspectives to show how health disparities vary across different life stages.

CONCLUSION

If the goal of health equality is to be achieved among diverse intersectional groups, future research must be assisted by the collection and examination of data that overcomes these limitations.

Concurrent and Longitudinal Associations of Sex and Race with Inflammatory Biomarkers during Adolescence

Chronic, systemic inflammation is implicated in physical and mental health; little is known about whether sex and racial differences detected in adulthood are observed during adolescence or about normative changes occurring during adolescence. This longitudinal, United States-based study examined four biomarkers of systemic inflammation [C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and IL-8) in 315 adolescents (51% female; 58% black; baseline age = 16.49 years (SD = 1.56; range: 12.14-21.28)] at three timepoints. Notable results included: general decline in inflammatory biomarkers in older adolescents, lower levels of TNF-α/IL-8 in black adolescents, elevated CRP/IL-6 in females, and especially higher levels of IL-6 in black, female adolescents. Implications are discussed, particularly the potential health implications of elevated IL-6 in black females.

The Role of Stress and Genital Immunity in Sexual Trauma and HIV Susceptibility Among Adolescent Girls and Adult Women (The THRIVE Study): Protocol for a Longitudinal Case-Control Study

BACKGROUND

The relationship between sexual violence and HIV risk has been extensively documented through social and behavioral research; however, the underlying biological mechanisms are poorly understood.

OBJECTIVE

The purpose of the THRIVE (Trauma and HIV Risk: Investigating Stress and the Immune Disruption of the Vaginal Environment) Study is to examine the impact of sexual trauma due to sexual violence on HIV susceptibility through dysregulation of soluble inflammatory and anti-inflammatory and anti-HIV biomarkers in the female genital tract and dysregulation of the hypothalamic-pituitary-adrenal axis among adolescent girls and adult women.

METHODS

The THRIVE Study is a longitudinal case-control study conducted in San Diego, CA, among a racially diverse sample. Cases are adolescent girls (aged 14-19 years) or adult women (aged 20-45 years) who have experienced forced vaginal penetration by a phallus perpetrated by a man within the past 15 days. Controls are adolescent girls or adult women who have engaged in consensual vaginal sex with a man within the past 15 days. At baseline and 1- and 3-month follow-up study visits, participants undergo a urine-based pregnancy test; venipuncture blood draw for HIV, C-reactive protein, adrenocorticotropic hormone, and progesterone testing; a 45-min interviewer-administered computer survey; and cervicovaginal lavage to measure proinflammatory and anti-inflammatory and anti-HIV soluble immune biomarkers. After each study visit, participants self-collect saliva specimens (upon waking, 30 min after waking, and 45 min after waking) at home for 3 consecutive days, which are later assayed for cortisol and dehydroepiandrosterone sulfate. Participants receive compensation at each study visit and for the return of saliva specimens, and a list of local medical and support services. Study procedures use trauma-informed care methods, given the sensitive nature of the study and enrollment of women in the acute phase after sexual trauma. All research staff and investigators adhere to ethical principles and guidelines in the conduct of research activities. Data will be analyzed for descriptive and inferential analyses.

RESULTS

The recruitment of participants is ongoing. The publication of the first results is expected by late 2021.

CONCLUSIONS

The THRIVE Study will provide foundational knowledge on how sexual trauma due to sexual violence increases susceptibility to HIV acquisition via alterations in cervicovaginal immune regulation and the psychobiology of the stress responses. These findings will inform future research on mechanistic models of in vitro and in vivo injury and cervicovaginal wound healing processes, which may lead to the development of nonvaccine biomedical HIV prevention products for girls and women.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/18190.

"We get double slammed!": Healthcare experiences of perceived discrimination among low-income African-American women

BACKGROUND

On account of their racial/ethnic minority status, class, and gender, African-American women of low socioeconomic status are among the least privileged, underserved, and most marginalized groups in the United States. Generally, African Americans continue to experience poorer health outcomes, in which disparities have been attributed to socioeconomic inequities and structural racism. This objective of this study was to explore the lived experiences of low-income African-American women in interacting with the healthcare system and healthcare providers.

METHODS

Twenty-two in-depth one-on-one interviews were conducted with low-income African-American women. The audio-recorded interviews were transcribed verbatim. An inductive content analysis was performed, using an analytical software, Dedoose® to enabled hierarchical coding. Codes were grouped into categories which were further analyzed for similarities that led to the emergence of themes.

RESULTS

A key finding was the experience of discriminatory treatment. The three themes that emerged relevant to this category were (1) perceived discrimination based on race/ethnicity, (2) perceived discrimination based on socioeconomic status, and (3) stereotypical assumptions such as drug-seeking and having sexually transmitted diseases.

CONCLUSION AND RECOMMENDATIONS

Low-income African-American women experience less than satisfactory patient care, where participants attribute to their experience of being stereotyped and their perception of discrimination in the healthcare system and from providers. Patients' experiences within the healthcare system have implications for their healthcare-seeking behaviors and treatment outcomes. Healthcare personnel and providers need to be more aware of the potential for implicit bias toward this population. Healthcare workforce training on culturally responsive patient care approaches and more community engagement will help providers better understand the context of patients from this population and more effectively meet their healthcare needs.

Promoting Cardiovascular Health for African American Women: An Integrative Review of Interventions

Background: African American (AA) women bear a disproportionate burden of cardiovascular disease. Promoting ideal cardiovascular health is one strategy to promote health equity for this disparate population. The goal of this integrative review was to summarize and evaluate the research evidence for cardiovascular risk reduction interventions specifically targeting, tailored, or adapted for AA women. Materials and Methods: A review of the literature was conducted using the EBSCOHost platform. Study elements from articles in the final analysis were extracted. Results: Fourteen interventions were included in the final analysis (16 peer-reviewed articles). Most studies targeted two or more areas of cardiovascular health with the most common areas being physical activity and diet. Primary and secondary outcome measures varied; the most common measures were self-reported dietary intake, physical activity, and knowledge-related measures. Eleven studies reported health outcomes; only five reported long-term intervention effects. Most studies employed at least one cultural tailoring or adaptation strategy for AA women. The most common strategies included incorporating feedback from the target population before implementation and tailoring intervention material to reflect the target population. Conclusions: There is a need to develop and evaluate tailored or adapted evidence-based interventions for AA women. Additional research is needed to design interventions for subgroups of the population such as low-income or rural AA women.

Contribution of the inflammasome to inflammaging

Background

Inflammation is a natural part of the aging process. This process is referred to as inflammaging. Inflammaging has been associated with deleterious outcomes in the aging brain in diseases such as Alzheimer’s disease and Parkinson’s disease. The inflammasome is a multi-protein complex of the innate immune response involved in the activation of caspase-1 and the processing of the inflammatory cytokines interleukin (IL)-1β and IL-18. We have previously shown that the inflammasome plays a role in the aging process in the brain. In this study, we analyzed the brain of young (3 months old) and aged (18 months old) mice for the expression of inflammasome proteins.

Results

Our findings indicate that the inflammasome proteins NLRC4, caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and IL-18 are elevated in the cytosol of cortical lysates in aged mice when compared to young. In addition, in the cytosolic fraction of hippocampal lysates in aged mice, we found an increase in NLRC4, caspase-1, caspase-11, ASC and IL-1β. Moreover, we found higher levels of ASC in the mitochondrial fraction of aged mice when compared to young, consistent with higher levels of the substrate of pyroptosis gasdermin-D (GSDM-D) and increased pyroptosome formation (ASC oligomerization). Importantly, in this study we obtained fibroblasts from a subject that donated his cells at three different ages (49, 52 and 64 years old (y/o)) and found that the protein levels of caspase-1 and ASC were higher at 64 than at 52 y/o. In addition, the 52 y/o cells were more susceptible to oxidative stress as determined by lactose dehydrogenase (LDH) release levels. However, this response was ameliorated by inhibition of the inflammasome with Ac-Tyr-Val-Ala-Asp-Chloromethylketone (Ac-YVAD-CMK). In addition, we found that the protein levels of ASC and IL-18 are elevated in the serum of subjects over the age of 45 y/o when compared to younger subjects, and that ASC was higher in Caucasians than Blacks and Hispanics, whereas IL-18 was higher in Caucasians than in blacks, regardless of age.

Conclusions

Taken together, our data indicate that the inflammasome contributes to inflammaging and that the inflammasome-mediated cell death mechanism of pyroptosis contributes to cell demise in the aging brain.