Three common assumptions about inflammation, aging, and health that are probably wrong.

Chronic inflammation contributes to the onset and progression of cardiovascular disease and other degenerative diseases of aging. But does it have to? This article considers the associations among inflammation, aging, and health through the lens of human population biology and suggests that chronic inflammation is not a normal nor inevitable component of aging. It is commonly assumed that conclusions drawn from research in affluent, industrialized countries can be applied globally; that aging processes leading to morbidity and mortality begin in middle age; and that inflammation is pathological. These foundational assumptions have shifted focus away from inflammation as a beneficial response to infection or injury and toward an understanding of inflammation as chronic, dysregulated, and dangerous. Findings from community-based studies around the world-many conducted in areas with relatively high burdens of infectious disease-challenge these assumptions by documenting substantial variation in levels of inflammation and patterns of association with disease. They also indicate that nutritional, microbial, and psychosocial environments in infancy and childhood play important roles in shaping inflammatory phenotypes and their contributions to diseases of aging. A comparative, developmental, and ecological approach has the potential to generate novel insights into the regulation of inflammation and how it relates to human health over the life course.

Evidence for an adolescent sensitive period to family experiences influencing adult male testosterone production.

Across vertebrates, testosterone is an important mediator of reproductive trade-offs, shaping how energy and time are devoted to parenting versus mating/competition. Based on early environments, organisms often calibrate adult hormone production to adjust reproductive strategies. For example, favorable early nutrition predicts higher adult male testosterone in humans, and animal models show that developmental social environments can affect adult testosterone. In humans, fathers' testosterone often declines with caregiving, yet these patterns vary within and across populations. This may partially trace to early social environments, including caregiving styles and family relationships, which could have formative effects on testosterone production and parenting behaviors. Using data from a multidecade study in the Philippines (n = 966), we tested whether sons' developmental experiences with their fathers predicted their adult testosterone profiles, including after they became fathers themselves. Sons had lower testosterone as parents if their own fathers lived with them and were involved in childcare during adolescence. We also found a contributing role for adolescent father­son relationships: sons had lower waking testosterone, before and after becoming fathers, if they credited their own fathers with their upbringing and resided with them as adolescents. These findings were not accounted for by the sons' own parenting and partnering behaviors, which could influence their testosterone. These effects were limited to adolescence: sons' infancy or childhood experiences did not predict their testosterone as fathers. Our findings link adolescent family experiences to adult testosterone, pointing to a potential pathway related to the intergenerational transmission of biological and behavioral components of reproductive strategies.

Threats to social safety and neuro-inflammatory mechanisms underlying sexual orientation disparities in depression symptom severity: A prospective cohort study of young adults.

Sexual minority individuals have a markedly elevated risk of depression compared to heterosexuals. We examined early threats to social safety and chronically elevated inflammation as mechanisms contributing to this disparity in depression symptoms, and compared the relative strength of the co-occurrence between chronic inflammation and depression symptoms for sexual minorities versus heterosexuals. To do so, we analyzed data from a prospective cohort of sexual minority and heterosexual young adults (n = 595), recruited from a nationally representative sample, that included assessments of early threats to social safety in the form of adverse childhood interpersonal events, three biomarkers of inflammation (i.e., CRP, IL-6, TNF-α) measured at two time points, and depression symptoms over four years. In pre-registered analyses, we found that sexual minorities experienced more adverse childhood interpersonal events, were more likely to display chronically elevated inflammation, and reported more severe depression symptoms than heterosexuals. Adverse childhood interpersonal events and chronically elevated inflammation explained approximately 23 % of the total effect of the association between sexual orientation and depression symptom severity. Further, there was an increased coupling of chronically elevated inflammation and depression symptoms among sexual minorities compared to heterosexuals. These results provide novel longitudinal, population-based evidence for the role of chronically elevated inflammation in linking threats to social safety during childhood with depression symptom severity in young adulthood, consistent with the primary tenets of the social signal transduction theory of depression. Our study extends this theory to the population level by finding that members of a stigmatized population (i.e., sexual minorities) experience a greater risk of depression because of their greater exposure to adverse childhood interpersonal events and the subsequent link to chronic inflammation, highlighting potential biopsychosocial intervention targets.

Socioeconomic status is negatively associated with immunosenescence but positively associated with inflammation among middle-aged women in Cebu, Philippines.

BACKGROUND: Socioeconomic status (SES) gradients in health are well-documented, and while biological pathways are incompletely understood, chronic inflammation and accelerated immune aging (immunosenescence) among lower SES individuals have been implicated. However, previous findings have come from samples in higher income countries, and it is unclear how generalizable they are to lower- and middle-income countries (LMIC) with different infectious exposures and where adiposity-an important contributor to chronic inflammation-might show different SES patterning. To address this gap, we explored associations between SES and inflammation and immunosenescence in a sample of women in Cebu, Philippines. METHODS: Data came from the mothers of the Cebu Longitudinal Health and Nutrition Survey birth cohort (mean age: 47.7, range: 35-69 years). SES was measured as a combination of annual household income, education level, and assets. Chronic inflammation was measured using C-reactive protein (CRP) in plasma samples from 1,834 women. Immunosenescence was measured by the abundance of exhausted CD8T (CD8 + CD28-CD45RA-) and naïve CD8T and CD4T cells, estimated from DNA methylation in whole blood in a random subsample of 1,028. Possible mediators included waist circumference and a collection of proxy measures of pathogen exposure. RESULTS: SES was negatively associated with the measures of immunosenescence, with slight evidence for mediation by a proxy measure for pathogen exposure from the household's drinking water source. In contrast, SES was positively associated with CRP, which was explained by the positive association with waist circumference. CONCLUSIONS: Similar to higher income populations, in Cebu there is an SES-gradient in pathogen exposures and immunosenescence. However, lifestyle changes occurring more rapidly among higher SES individuals is contributing to a positive association between SES and adiposity and inflammation. Our results suggest more studies are needed to clarify the relationship between SES and inflammation and immunosenescence across LMIC.

Implementation of a minimally invasive cell culture system to measure the regulation of inflammation in a school-based sample of adolescents.

Dysregulated inflammation underlies many human diseases, and measures of responsiveness to activation, and sensitivity to inhibition, provide important information beyond baseline assessments of chronic inflammation. This study implements a simplified cell culture protocol in a school-based setting, using finger stick capillary blood collected from 333 adolescents (age 11.4-15.6 years) incubated with lipopolysaccharide (LPS). Median cytokine responses for IL6, IL1ß, and TNFα were 61.9, 26.2, and 11.2 pg/mL, respectively. Samples were also incubated with LPS and glucocorticoid (GC) to measure GC sensitivity. Median responses were reduced in the presence of GC inhibition for IL6 (20.3 pg/mL), IL1ß (10.5 pg/mL), and TNFα (3.3 pg/mL). Minimally invasive cell culture protocols provide novel opportunities for measuring inflammatory phenotypes in a wide range of non-clinical settings.

C-reactive protein (CRP) in high altitude Bolivian peri-urban adolescents varies by adiposity, current illness, height, socioeconomic status, sex, and menarcheal status: The potential benefits and costs of adipose reserves in arduous environments.

OBJECTIVES: In non-industrialized and low-income populations, adipose stores can serve as a valuable buffer against harsh conditions such as seasonal food scarcity. However, these reserves may incur costs due to adipocytes' production of pro-inflammatory cytokines; inflammation is associated with increased risk for cardiometabolic diseases later in life. Life history theory posits that, especially in populations with high juvenile mortality, higher adiposity may nonetheless be advantageous if its benefits in early life outweigh its later costs. Relatively little is known about adolescents' C-reactive protein concentration (CRP; an inflammation biomarker) in such environments. We investigated CRP and its associations with several hypothesized predictors in adolescents in an economically diverse peri-urban Andean community. METHODS: We measured CRP in dried blood spots and collected data on anthropometrics, illnesses, socioeconomic status (SES), and menarcheal status in 59 female and 40 male adolescents ("Alteños", 11.0-14.9 years old) with normal vital signs in El Alto, Bolivia (~4150 m amsl). We used Cole's LMS method to standardize all anthropometrics for sex and age, and principal components analysis to construct a "fat-factor" variable loading on these standardized z-scores. We used multiple linear regression to assess the influence of fat-factor and other likely predictors on CRP rank. RESULTS: Compared to a national Bolivian growth reference, Alteños were, on average, shorter and leaner; only 6% were classified as overweight and none were obese. Pre-menarche females were on average leaner than post-menarche females. The best-fitting model explained 24% of the variance in CRP rank. Significant predictors were fat-factor, SES, current illness for males and pre-menarche females, and z-height for females. CONCLUSIONS: Our results are consistent with a tradeoff between investments in growth versus immune functioning, as might be expected in an environment with limited resources and high pathogen exposure (e.g., soil-transmitted helminths, poor sanitation). Thinner Alteños appear to maintain a minimum CRP concentration independent of fat-factor, while fatter (or less-thin) Alteños' CRP rises with fat-factor. Female Alteños appear to be trading off investment in immune response for investment in growth and maturation. Alteños' high rate of stunting and absence of obesity suggests chronic, presumably multifactorial, stress. Adipose stores likely buffer against some of these stressors and, in an environment such as this-in which many lack sufficient nutritious foods, potable water, adequate sewage, and health care-may confer a net lifetime benefit.

OBJETIVOS: En poblaciones no industrializadas y de bajos ingresos, las reservas adiposas pueden servir como un valioso amortiguador frente a condiciones duras como la escasez estacional de alimentos. Sin embargo, estas reservas pueden tener un coste debido a la producción de citoquinas proinflamatorias por parte de los adipocitos; la inflamación se asocia a un mayor riesgo de enfermedades cardiometabólicas en etapas posteriores de la vida. La teoría de la historia vital postula que, especialmente en poblaciones con una elevada mortalidad juvenil, una mayor adiposidad puede ser ventajosa si sus beneficios en los primeros años de vida compensan sus costes posteriores. Se sabe relativamente poco sobre la concentración de proteína C reactiva (PCR; un biomarcador de inflamación) de los adolescentes. Investigamos la PCR y sus asociaciones con varios predictores hipotéticos en adolescentes de una comunidad andina periurbana económicamente diversa. MÉTODOS: Se midió la PCR en muestras de sangre seca y se recogieron datos sobre antropometría, enfermedades, nivel socioeconómico (NSE) y menarquia en 59 mujeres y 40 varones adolescentes («alteños¼, 11,0­14,9 años de edad) con signos vitales normales en El Alto, Bolivia (~4150m amsl). Usamos el método LMS de Cole para estandarizar todos los parámetros antropométricos para sexo y edad, y análisis de componentes principales para construir una variable «factor de grasa¼ cargada en estos puntajes z­estandarizados. Se utilizó la regresión lineal múltiple para evaluar la influencia del factor grasa y otros posibles predictores en el rango de la PCR. RESULTADOS: En comparación con una referencia nacional boliviana de crecimiento, los alteños eran, en promedio, más bajos y más delgados; sólo el 6% estaban clasificados con sobrepeso y ninguno era obeso. Las chicas premenárquicos eran, en promedio, más delgados que las chicas postmenárquicos. El modelo de regresión que mejor se ajustaba explicaba el 24% de la varianza en el rango de PCR. Observamos una nueva asociación entre la adiposidad y la PCR. Cuando el factor adiposidad es >0, el rango de la PCR aumenta linealmente con el factor adiposidad. Cuando el factor adiposidad es <0, la PCR no varía con el factor adiposidad. Estos patrones sugieren que los Alteños más delgados mantienen una concentración mínima de PCR independiente del factor adiposidad, mientras que la PCR de los Alteños más gordos (menos delgados) aumenta con el factor adiposidad. Además, existe una mayor variación en el rango de la PCR en los adolescentes más delgados que en los más gordos. El autoinforme de una enfermedad actual en niños y niñas premenárquicas se asoció con una PCR significativamente más alta. La ausencia de una asociación significativa entre la enfermedad actual y la PCR en las chicas postmenárquicas puede reflejar confusión por cambios en la PCR durante el ciclo menstrual. Manteniendo constantes todos los demás factores predictivos, la PCR aumentó con el incremento del nivel socioeconómico. En las niñas, el aumento de la estatura se asoció a una disminución de la PCR, lo que sugiere que las niñas favorecen la inversión en crecimiento y maduración frente a la inversión en respuestas inmunitarias inflamatorias a corto plazo. En los chicos, no se observó una relación significativa entre la estatura y la PCR. La baja estatura y la delgadez de estos adolescentes sugieren que pueden estar invirtiendo en defensas humorales a más largo plazo (por ejemplo, anticuerpos contra helmintos), pero esta hipótesis requiere más estudios. CONCLUSIONES: La alta tasa de retraso en el crecimiento y la ausencia de obesidad de los alteños sugieren un estrés crónico, presumiblemente multifactorial. Muchas familias carecen de alimentos nutritivos suficientes, agua potable, alcantarillado adecuado y atención sanitaria. Es probable que las reservas adiposas amortigüen algunos de estos factores de estrés y confieran un beneficio neto a lo largo de la vida (la reducción de la mortalidad juvenil puede compensar cualquier aumento del riesgo de enfermedades cardiometabólicas en etapas posteriores de la vida). Sin embargo, estas compensaciones tienen un coste para los individuos y las sociedades. Reducir los riesgos de patógenos y mejorar la capacidad de los habitantes del altiplano para acceder sistemáticamente a agua limpia y a alimentos sanos suficientes y asequibles probablemente reportaría beneficios para la salud a lo largo de toda la vida.

Intimate partner violence, depression, and chronic low-grade inflammation among middle-aged women in Cebu, Philippines.

OBJECTIVES: Recent discussions in human biology have highlighted how local ecological contexts shape the relationship between social stressors and health across populations. Chronic low-grade inflammation has been proposed as a pathway linking social stressors to health, with evidence concentrated in high-income Western contexts. However, it remains unclear whether this is an important pathway in populations where prevalence is lower due to lower adiposity and greater infectious exposures. To investigate this further, we tested associations between multiple types of intimate partner violence (IPV), a highly prevalent stressor and health crisis globally, and C-reactive protein (CRP), a commonly used measure of chronic low-grade inflammation, in Cebu, Philippines. For reference, we compared results for CRP to depression, a well-established and consistently observed health outcome of IPV. METHODS: Data came from 1601 currently partnered women (ages 35-69 years) as part of the Cebu Longitudinal Health and Nutrition Survey. IPV exposures included physical, emotional, and controlling behavior. Depression scores were measured using a modified version of the Center for Epidemiologic Studies-Depression Scale for this population, whereas plasma CRP was measured from overnight-fasted morning blood samples. RESULTS: All three types of IPV were associated with a higher depression score. However, none of the IPV measures were associated with CRP. In a post hoc interaction test, emotional IPV became positively associated with CRP as waist circumference increased above the mean. CONCLUSIONS: Our results suggest a complex relationship between social stressors and chronic low-grade inflammation, which is likely dependent on the population-specific context of lifestyle and environmental factors.

Infectious Illness Symptoms Are Associated with Elevated Anxiety in a Sample of Sexual and Gender Minority Young Adults During the COVID-19 Pandemic.

BACKGROUND: To evaluate whether infectious illness symptoms (IIS) are associated with generalized anxiety symptoms during the COVID-19 pandemic in sexual/gender (SGM) minority young adults assigned male at birth (AMAB). METHOD: Four hundred eighteen participants (median age = 25; range, 20-40) were recruited through RADAR, an ongoing Chicago-based cohort study of SGM-AMAB between September 2020 and February 2021. Participants completed online surveys. A subset (n = 145) provided dried blood spot samples to assess SARS-CoV-2 serostatus. RESULTS: One hundred twenty participants (28.7%) had GAD-7 scores of 10 or greater, which indicates generalized anxiety symptoms that may be clinically significant. In a binomial logistic regression model adjusting age, gender identity, race/ethnicity, substance use, and HIV status, the authors found that having a higher IIS count since March 1, 2020, was associated with greater odds of having a GAD-7 score of 10 or greater (OR = 1.14; 95% CI, 1.04, 1.25; P = 0.007). This effect was more pronounced in a binomial logistic regression model adjusting for the same covariates but using current IIS count as the independent variable (OR = 1.39; 95% CI, 1.13, 1.74; P = 0.002). CONCLUSION: Among SGM-AMAB young adults, those who experienced ISS reported higher scores on the GAD-7, a widely used and validated screening measure for generalized anxiety symptoms. These findings highlight the importance of screening for anxiety disorders when patients present with IIS in clinical settings and psychobehavioral health follow-ups when indicated.

Evaluation of a Photo Captioning Cognitive Empathy Intervention for Dementia Caregivers.

OBJECTIVES: The goal of this study was to develop and evaluate an intervention aimed at increasing cognitive empathy, improving mental health, and reducing inflammation in dementia caregivers, and to examine the relevant neural and psychological mechanisms. METHODS: Twenty dementia caregivers completed an intervention that involved taking 3-5 daily photographs of their person living with dementia (PLWD) over a period of 10 days and captioning those photos with descriptive text capturing the inner voice of the PLWD. Both before and after the intervention, participants completed questionnaires, provided a blood sample for measures of inflammation, and completed a neuroimaging session to measure their neural response to viewing photographs of their PLWD and others. RESULTS: 87% of enrolled caregivers completed the intervention. Caregivers experienced pre- to post-intervention increases in cognitive empathy (i.e. Perspective-Taking) and decreases in both burden and anxiety. These changes were paralleled by an increased neural response to photographs of their PLWD within brain regions implicated in cognitive empathy. CONCLUSION: These findings warrant a larger replication study that includes a control condition and follows participants to establish the duration of the intervention effects. CLINICAL IMPLICATIONS: Cognitive empathy interventions may improve caregiver mental health and are worthy of further investigation.

Trauma History Predicts Decoupling of C-Reactive Protein and Somatic Symptoms: Results From a Cohort Study of Sexual and Gender Minority Youth.

OBJECTIVE: Systemic inflammation can induce somatic symptoms (e.g., pain, nausea, fatigue) through neuroimmune signaling pathways. Previous research suggests that early-life adversity amplifies signaling between peripheral inflammation and the brain. We therefore hypothesized that greater lifetime trauma exposure at baseline would predict stronger associations between systemic inflammation and somatic symptoms at 2.5-year follow-up in a cohort study of sexual and gender minority youth assigned male at birth ( n = 694). METHODS: We measured prior trauma exposure (lifetime count of traumatic event types reported at baseline), somatic symptoms (Brief Symptom Inventory somatization score), and systemic inflammation (C-reactive protein, interleukin 6, interleukin 1ß, and tumor necrosis factor α). All models included age, gender, education, recent trauma exposure, substance use, body mass index, and HIV status as covariates. RESULTS: Higher C-reactive protein concentrations were associated with greater somatic symptoms in the main effects model ( ß = 0.019, 95% confidence interval [CI] = 0.006 to 0.031). Contrary to our hypothesis, we observed a negative interaction between prior trauma exposure and C-reactive protein levels in predicting somatic symptoms ( ß = -0.017, 95% CI = -0.030 to -0.004). Higher C-reactive protein was associated with greater somatic symptoms only in participants without prior trauma exposure at baseline ( ß = 0.044, 95% CI = 0.026 to 0.062). Specificity analyses revealed similar patterns when nonsomatic depressive symptoms were used as the outcome variable. CONCLUSIONS: These results suggest that sexual and gender minority youth assigned male at birth who have a history of prior trauma exposure may experience decoupling of systemic inflammation and somatic symptoms. The absence of inflammation-related symptoms may prevent individuals from seeking necessary medical care by reducing interoceptive awareness of pathological states.

Employee Cardiometabolic Risk Following a Cluster-Randomized Workplace Intervention From the Work, Family and Health Network, 2009-2013.

Objectives. To examine whether workplace interventions to increase workplace flexibility and supervisor support and decrease work-family conflict can reduce cardiometabolic risk. Methods. We randomly assigned employees from information technology (n = 555) and long-term care (n = 973) industries in the United States to the Work, Family and Health Network intervention or usual practice (we collected the data 2009-2013). We calculated a validated cardiometabolic risk score (CRS) based on resting blood pressure, HbA1c (glycated hemoglobin), HDL (high-density lipoprotein) and total cholesterol, height and weight (body mass index), and tobacco consumption. We compared changes in baseline CRS to 12-month follow-up. Results. There was no significant main effect on CRS associated with the intervention in either industry. However, significant interaction effects revealed that the intervention improved CRS at the 12-month follow-up among intervention participants in both industries with a higher baseline CRS. Age also moderated intervention effects: older employees had significantly larger reductions in CRS at 12 months than did younger employees. Conclusions. The intervention benefited employee health by reducing CRS equivalent to 5 to 10 years of age-related changes for those with a higher baseline CRS and for older employees. Trial Registration. ClinicalTrials.gov Identifier: NCT02050204. (Am J Public Health. 2023;113(12):1322-1331. https://doi.org/10.2105/AJPH.2023.307413).

Association between infectious exposures in infancy and epigenetic age acceleration in young adulthood in metropolitan Cebu, Philippines.

OBJECTIVES: The drivers of human life expectancy gains over the past 200 years are not well-established, with a potential role for historical reductions in infectious disease. We investigate whether infectious exposures in infancy predict biological aging using DNA methylation-based markers that forecast patterns of morbidity and mortality later in life. METHODS: N = 1450 participants from the Cebu Longitudinal Health and Nutrition Survey-a prospective birth cohort initiated in 1983-provided complete data for the analyses. Mean chronological age was 20.9 years when venous whole blood samples were drawn for DNA extraction and methylation analysis, with subsequent calculation of three epigenetic age markers: Horvath, GrimAge, and DunedinPACE. Unadjusted and adjusted least squares regression models were evaluated to test the hypothesis that infectious exposures in infancy are associated with epigenetic age. RESULTS: Birth in the dry season, a proxy measure for increased infectious exposure in the first year of life, as well as the number of symptomatic infections in the first year of infancy, predicted lower epigenetic age. Infectious exposures were associated with the distribution of white blood cells in adulthood, which were also associated with measures of epigenetic age. CONCLUSIONS: We document negative associations between measures of infectious exposure in infancy and DNA methylation-based measures of aging. Additional research, across a wider range of epidemiological settings, is needed to clarify the role of infectious disease in shaping immunophenotypes and trajectories of biological aging and human life expectancy.

Biological embedding of experience: A primer on epigenetics.

Biological embedding occurs when life experience alters biological processes to affect later life health and well-being. Although extensive correlative data exist supporting the notion that epigenetic mechanisms such as DNA methylation underlie biological embedding, causal data are lacking. We describe specific epigenetic mechanisms and their potential roles in the biological embedding of experience. We also consider the nuanced relationships between the genome, the epigenome, and gene expression. Our ability to connect biological embedding to the epigenetic landscape in its complexity is challenging and complicated by the influence of multiple factors. These include cell type, age, the timing of experience, sex, and DNA sequence. Recent advances in molecular profiling and epigenome editing, combined with the use of comparative animal and human longitudinal studies, should enable this field to transition from correlative to causal analyses.

Sleep Variability and Inflammation in Midlife and Older Women.

OBJECTIVE: Shorter sleep duration and more sleep disturbances, in addition to greater night-to-night fluctuations in sleep (intraindividual variability; IIV), have been associated with elevated inflammation. However, these associations were only at the between-person level. The current study examined the within-person relationship between mean levels and IIV of sleep duration and sleep disturbances and C-reactive protein (CRP) in healthy, aging women. METHODS: Participants ( N = 179) from a longitudinal study of activity and well-being in middle-aged and older women (mean age = 62 years; range = 50-75 years) completed a 7-day daily diary, every 3 months, for 2 years (up to nine bursts). Sleep was assessed each day asking participants how many hours of sleep they got the night before and with the four-item PROMIS Sleep Disturbance Short Form. Finger-stick dried blood spot samples were collected after each 7-day daily diary. RESULTS: In bursts when women experienced greater than average variability in sleep duration, they had higher CRP ( γ = 0.06, p = .004). Within-person changes in mean sleep duration were not associated with CRP. In addition, neither mean sleep disturbances nor sleep disturbance IIV were associated with CRP. CONCLUSIONS: This study is the first to show that within-person changes in variable sleep duration are related to changes in inflammation. Findings from the current study suggest that greater variability in sleep duration is related to higher CRP, which may increase risk for early morbidity and mortality. Future studies should investigate inflammation as a pathway linking sleep variability and health.

Associations between perceived discrimination and immune cell composition in the Jackson Heart Study.

African American adults suffer disproportionately from several non-communicable and infectious diseases. Among numerous contributing factors, perceived discrimination is considered a stressor for members of historically marginalized groups that contributes to health risk, although biological pathways are incompletely understood. Previous studies have reported associations between stress and both an up-regulation of non-specific (innate) inflammation and down-regulation of specific (adaptive) immunity. While associations between perceived discrimination and markers of inflammation have been explored, it is unclear if this is part of an overall shift that also includes down-regulated adaptive immunity. Relying on a large cross-section of African American adults (n = 3,319) from the Jackson Heart Study (JHS) in Jackson, Mississippi, we tested whether perceived everyday and lifetime discrimination as well as perceived burden from lifetime discrimination were associated with counts of neutrophils (innate), monocytes (innate), lymphocytes (adaptive), and the neutrophil-to-lymphocyte ratio (NLR), derived from complete white blood cell counts with differential. In addition, DNA methylation (DNAm) was measured on the EPIC array in a sub-sample (n = 1,023) of participants, allowing estimation of CD4T, CD8T and B lymphocyte proportions. Unexpectedly, high lifetime discrimination compared to low was significantly associated with lower neutrophils (b : -0.14, [95% CI: -0.24, -0.04]) and a lower NLR (b : -0.15, [95% CI: -0.25, -0.05]) after controlling for confounders. However, high perceived burden from lifetime discrimination was significantly associated with higher neutrophils (b : 0.17, [95% CI: 0.05, 0.30]) and a higher NLR (b : 0.16, [95% CI: 0.03, 0.29]). High perceived burden was also associated with lower lymphocytes among older men, which our analysis suggested might have been attributable to differences in CD4T cells. These findings highlight immune function as a potentially important pathway linking perceived discrimination to health outcomes.

Neither environmental unpredictability nor harshness predict reliance on alloparental care among families in Cebu, Philippines.

Alloparental caregiving is key to humans' highly flexible reproductive strategies. Across species and across societies, alloparental care is more common in harsh and/or unpredictable environments (HUEs). Currently, however, it is unclear whether HUEs predict intra-population variation in alloparental care, or whether early life HUEs might predict later alloparental care use in adulthood, consistent with adaptive developmental plasticity. We test whether harshness measures (socioeconomic status (SES), environmental hygiene, crowding) and unpredictability measures (parental unemployment, paternal absence, household moves) predicted how much alloparental assistance families in Cebu, Philippines received, in a multigenerational study with data collected across four decades. Though worse environmental hygiene predicted more concurrent alloparental care in 1994, we found little evidence that HUEs predict within-population variation in alloparental care in this large-scale, industrialized society. Indeed, less-crowded conditions and higher SES predicted more alloparental care, not less, in the 1980s and in 2014 respectively, while paternal absence in middle childhood predicted less reliance on alloparental care in adulthood. In this cultural context, our results generally do not provide support for the translation of interspecific or intersocietal patterns linking HUEs and alloparental care to intra-population variation in alloparental care, nor for the idea that a reproductive strategy emphasizing alloparental care use may be preceded by early life HUEs.

Association between C-reactive protein response to influenza vaccine during pregnancy and birth outcomes.

OBJECTIVE: A growing body of evidence suggests inflammatory markers can help predict poor outcomes in pregnancy. We evaluated C-reactive protein (CRP)-a key biomarker of inflammation-before and after a safe immune provocation (the seasonal influenza vaccine) during pregnancy. We evaluated predictors of the magnitude of response, as well as the association between CRP response and birth outcomes. METHODS: Nonrandomized prospective cohort trial measuring CRP before and 3 days after administering seasonal flu vaccine to low-risk obstetrical patients in Calgary, Alberta. RESULTS: We analyzed 27 prevaccination/postvaccination samples. Body mass index (BMI) was positively associated with CRP at Day 0, and women with higher prepregnancy BMI had a less robust response to vaccination than did leaner women. There was a strong positive association between CRP response and infant birth weight; women who had the greatest response to vaccination (by tertile) gave birth to babies that weighed, on average, 256.2 g more than babies born to women with the lowest response. CONCLUSIONS: Higher BMI in pregnant women was associated with higher baseline CRP and less pronounced CRP response to vaccination. Stronger CRP response was associated with higher birth weight. These findings underscore the potential value of a more dynamic approach to studying the regulation of inflammation during pregnancy and its implications for birth outcomes. This study was registered as a clinical trial in clinicaltrials.gov (ID: REB15/1418).

Preliminary Effects of Mindfulness Training on Inflammatory Markers and Blood Pressure in Young Adult Survivors of Cancer: Secondary Analysis of a Pilot Randomized Controlled Trial.

BACKGROUND: This was a secondary analysis of a pilot randomized controlled trial (RCT) of mindfulness-based stress reduction (MBSR) among young adult (YA) survivors of cancer, which showed preliminary evidence for improving psychosocial outcomes. Secondary outcomes assessed were the feasibility of collecting biological data from YAs and preliminary effects of MBSR on markers of inflammation and cardiovascular function. METHOD: Participants were randomized to 8-week MBSR or a waitlist control condition. Participants provided whole blood spot samples for analysis of C-reactive protein (CRP) and interleukin (IL)-6 as well as blood pressure data in-person at baseline and 16-week follow-up. Feasibility was assessed with rates of providing biological data. Linear mixed effects modeling was used to evaluate preliminary effects of MBSR on inflammatory markers and blood pressure over time. RESULTS: Of 126 total participants enrolled, 77% provided biological data at baseline (n = 48/67 MBSR, n = 49/59 control). At 16 weeks, 97% of the 76 retained participants provided follow-up biological data (n = 34/35 MBSR, n = 40/41 control). Relative to the control group, MBSR was associated with decreased systolic blood pressure (p = 0.042, effect sizes (ES) = 0.45) and decreased diastolic blood pressure (p = 0.017, ES = 0.64). There were no changes in CRP or IL-6. CONCLUSION: This was the first study to explore the feasibility of collecting biological data from YA survivors of cancer and assess preliminary effects of MBSR on inflammatory and cardiovascular markers in an RCT. Minimally invasive biological data collection methods were feasible. Results provide preliminary evidence for the role of MBSR in improving cardiovascular outcomes in this population, and results should be replicated.

COVID-19 mRNA Vaccination Generates Greater Immunoglobulin G Levels in Women Compared to Men.

We investigated whether the antibody response to coronavirus disease 2019 (COVID-19) mRNA vaccination is similar in women and men. In a community cohort without prior COVID-19, first vaccine dose produced higher immunoglobulin G (IgG) levels and percent inhibition of spike-ACE2 receptor binding, a surrogate measure of virus neutralization, in women compared to men (7.0 µg/mL, 51.6% vs 3.3 µg/mL, 36.4%). After 2 doses, IgG levels remained significantly higher for women (30.4 µg/mL) compared to men (20.6 µg/mL), while percent inhibition was similar (98.4% vs 97.7%). Sex-specific antibody response to mRNA vaccination informs future efforts to understand vaccine protection and side effects.

Out of the Laboratory and Into the Field: Validation of Portable Cell Culture Protocols.

OBJECTIVE: Field-based research on inflammation and health is typically limited to baseline measures of circulating cytokines or acute-phase proteins, whereas laboratory-based studies can pursue a more dynamic approach with ex vivo cell culture methods. The laboratory infrastructure required for culturing leukocytes limits application in community-based settings, which in turn limits scientific understandings of how psychosocial, behavioral, and contextual factors influence the regulation of inflammation. We aim to address this gap by validating two "field-friendly" cell culture protocols, one using a small volume of venous whole blood and another using finger-stick capillary whole blood. METHODS: We evaluated the performance of both protocols against a standard laboratory-based protocol using matched venous and capillary blood samples collected from young adults (n = 24). Samples were incubated with lipopolysaccharide and hydrocortisone, and the production of proinflammatory cytokines interleukin 1ß, interleukin 6, and tumor necrosis factor α was measured in response. RESULTS: Comparisons indicate a high level of agreement in responses across the protocols and culture conditions. The overall correlation in results was 0.88 between the standard and small-volume protocols and 0.86 between the standard and capillary blood protocols. Repeatability for the small-volume and capillary blood protocols was high, with mean coefficients of variation across five replicates of 6.2% and 5.4%, respectively. CONCLUSIONS: These results demonstrate the feasibility of culturing cells and quantifying the inflammatory response to challenge outside the laboratory, with a wide range of potential applications in biobehavioral research in community-based and remote field settings.