Early Experiences of Threat, but Not Deprivation, Are Associated With Accelerated Biological Aging in Children and Adolescents

BACKGROUND

Recent conceptual models argue that early life adversity (ELA) accelerates development, which may contribute to poor mental and physical health outcomes. Evidence for accelerated development in youths comes from studies of telomere shortening or advanced pubertal development following circumscribed ELA experiences and neuroimaging studies of circuits involved in emotional processing. It is unclear whether all ELA is associated with accelerated development across global metrics of biological aging or whether this pattern emerges following specific adversity types.

METHODS

In 247 children and adolescents 8 to 16 years of age with wide variability in ELA exposure, we evaluated the hypothesis that early environments characterized by threat, but not deprivation, would be associated with accelerated development across two global biological aging metrics: DNA methylation (DNAm) age and pubertal stage relative to chronological age. We also examined whether accelerated development explained associations of ELA with depressive symptoms and externalizing problems.

RESULTS

Exposure to threat-related ELA (e.g., violence) was associated with accelerated DNAm age and advanced pubertal stage, but exposure to deprivation (e.g., neglect, food insecurity) was not. In models including both ELA types, threat-related ELA was uniquely associated with accelerated DNAm age (β = .18) and advanced pubertal stage (β = .28), whereas deprivation was uniquely associated with delayed pubertal stage (β = -.21). Older DNAm age was related to greater depressive symptoms, and a significant indirect effect of threat exposure on depressive symptoms was observed through DNAm age.

CONCLUSIONS

Early threat-related experiences are particularly associated with accelerated biological aging in youths, which may be a mechanism linking ELA with depressive symptoms.

Epigenetic meta-analysis across three civilian cohorts identifies NRG1 and HGS as blood-based biomarkers for post-traumatic stress disorder

AIM

Trauma exposure is a necessary, but not deterministic, contributor to post-traumatic stress disorder (PTSD). Epigenetic factors may distinguish between trauma-exposed individuals with versus without PTSD.

MATERIALS & METHODS

We conducted a meta-analysis of PTSD epigenome-wide association studies in trauma-exposed cohorts drawn from civilian contexts. Whole blood-derived DNA methylation levels were analyzed in 545 study participants, drawn from the three civilian cohorts participating in the PTSD working group of the Psychiatric Genomics Consortium.

RESULTS

Two CpG sites significantly associated with current PTSD in NRG1 (cg23637605) and in HGS (cg19577098).

CONCLUSION

PTSD is associated with differential methylation, measured in blood, within HGS and NRG1 across three civilian cohorts.

Inhibition of DNA Methylation With Zebularine Alters Lipopolysaccharide-Induced Sickness Behavior and Neuroinflammation in Mice

Activity of DNA methyltransferases (DNMTs), the enzymes that catalyze DNA methylation, is dynamically regulated in the brain. DNMT inhibitors alter DNA methylation globally in the brain and at individual neural plasticity-associated genes, but how DNMT inhibitors centrally influence lipopolysaccharide (LPS)-induced neuroinflammation is not known. We investigated whether the DMNT inhibitor, zebularine, would alter sickness behavior, DNA methylation of the Il-1β promoter and expression of inflammatory genes in hippocampus and microglia. Contrary to our hypothesis that zebularine may exaggerate LPS-induced sickness response and neuroinflammation, adult mice treated with an intracerebroventricular (ICV) injection of zebularine prior to LPS had surprisingly faster recovery of burrowing behavior compared to mice treated with LPS. Further, genes of inflammatory markers, epigenetic regulators, and the microglial sensory apparatus (i.e., the sensome) were differentially expressed by zebularine alone or in combination with LPS. Bisulfite pyrosequencing revealed that ICV zebularine led to decreased DNA methylation of two CpG sites near the Il-1β proximal promoter alone or in combination with LPS. Zebularine treated mice still exhibited decreased DNA methylation 48 h after treatment when LPS-induced sickness behavior as well as hippocampal and microglial gene expression were similar to control mice. Taken together, these data suggest that decreased DNA methylation, specifically of the Il-1β promoter region, with a DNMT inhibitor in the brain disrupts molecular mechanisms of neuroinflammation.

Traumatic stress and accelerated DNA methylation age: A meta-analysis

BACKGROUND

Recent studies examining the association between posttraumatic stress disorder (PTSD) and accelerated aging, as defined by DNA methylation-based estimates of cellular age that exceed chronological age, have yielded mixed results.

METHODS

We conducted a meta-analysis of trauma exposure and PTSD diagnosis and symptom severity in association with accelerated DNA methylation age using data from 9 cohorts contributing to the Psychiatric Genomics Consortium PTSD Epigenetics Workgroup (combined N = 2186). Associations between demographic and cellular variables and accelerated DNA methylation age were also examined, as was the moderating influence of demographic variables.

RESULTS

Meta-analysis of regression coefficients from contributing cohorts revealed that childhood trauma exposure (when measured with the Childhood Trauma Questionnaire) and lifetime PTSD severity evidenced significant, albeit small, meta-analytic associations with accelerated DNA methylation age (ps = 0.028 and 0.016, respectively). Sex, CD4T cell proportions, and natural killer cell proportions were also significantly associated with accelerated DNA methylation age (all ps < 0.02). PTSD diagnosis and lifetime trauma exposure were not associated with advanced DNA methylation age. There was no evidence of moderation of the trauma or PTSD variables by demographic factors.

CONCLUSIONS

Results suggest that traumatic stress is associated with advanced epigenetic age and raise the possibility that cells integral to immune system maintenance and responsivity play a role in this. This study highlights the need for additional research into the biological mechanisms linking traumatic stress to accelerated DNA methylation age and the importance of furthering our understanding of the neurobiological and health consequences of PTSD.

Neuroepigenetics of Post-Traumatic Stress Disorder

While diagnosis of PTSD is based on behavioral symptom clusters that are most directly associated with brain function, epigenetic studies of PTSD in humans to date have been limited to peripheral tissues. Animal models of PTSD have been key for understanding the epigenetic alterations in the brain most directly relevant to endophenotypes of PTSD, in particular those pertaining to fear memory and stress response. This chapter provides an overview of neuroepigenetic studies based on animal models of PTSD, with an emphasis on the effect of stress on fear memory. Where relevant, we also describe human-based studies with relevance to neuroepigenetic insights gleaned from animal work and suggest promising directions for future studies of PTSD neuroepigenetics in living humans that combine peripheral epigenetic measures with measures of central nervous system activity, structure and function.

Genomic Approaches to Posttraumatic Stress Disorder: The Psychiatric Genomic Consortium Initiative

Posttraumatic stress disorder (PTSD) after exposure to a traumatic event is a highly prevalent psychiatric disorder. Heritability estimates from twin studies as well as from recent molecular data (single nucleotide polymorphism-based heritability) indicate moderate to high heritability, yet robust genetic variants for PTSD have not yet been identified and the genetic architecture of this polygenic disorder remains largely unknown. To date, fewer than 10 large-scale genome-wide association studies of PTSD have been published, with findings that highlight the unique challenges for PTSD genomics, including a complex diagnostic entity with contingency of PTSD diagnosis on trauma exposure and the large genetic diversity of the study populations. The Psychiatric Genomics Consortium PTSD group has brought together more than 200 scientists with the goal to increase sample size for genome-wide association studies and other genomic analyses to sufficient numbers where robust discoveries of molecular signatures can be achieved. The sample currently includes more than 32,000 PTSD cases and 100,000 trauma-exposed control subjects, and collection is ongoing. The first results found a significant shared genetic risk of PTSD with other psychiatric disorders and sex-biased heritability estimates with higher heritability in female individuals compared with male individuals. This review describes the scope and current focus of the Psychiatric Genomics Consortium PTSD group and its expansion from the initial genome-wide association study group to nine working groups, including epigenetics, gene expression, imaging, and integrative systems biology. We further briefly outline recent findings and future directions of "omics"-based studies of PTSD, with the ultimate goal of elucidating the molecular architecture of this complex disorder to improve prevention and intervention strategies.

Transgenerational effects of the genocide against the Tutsi in Rwanda: A post-traumatic stress disorder symptom domain analysis

Background: A number of studies have investigated transgenerational effects of parental post-traumatic stress disorder (PTSD) and its repercussions for offspring. Few studies however, have looked at this issue in the African context. Methods: The present study addresses this gap, utilizing confirmatory factor analysis (CFA), to investigate symptom severity within the three Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) PTSD symptom domains in mothers exposed to the genocide against the Tutsi in Rwanda (n=25) and offspring (n=25), and an ethnically matched control group of mothers (n=25) and offspring (n=25) who were outside of Rwanda during the genocide. All mothers were pregnant during the time of the genocide with the offspring included in the study. Missing data were excluded from the analyses. Results: We found that among the three symptom domains of PTSD, the re-experiencing symptom domain loaded most strongly onto PTSD among mothers directly exposed to the genocide (Beta = 0.95). In offspring of exposed mothers, however, the three symptom domains of PTSD yielded almost equal loading values (Beta range = 0.84-0.86). Conversely, among non-exposed mothers and their offspring, the hyperarousal symptom domain of PTSD loaded most strongly onto PTSD (Beta = 1.00, Beta = 0.94, respectively). As a secondary analysis, we also explored the relation between DNA methylation in the glucocorticoid receptor (NR3C1) locus, an important stress modulating gene, and individual PTSD symptom domains, finding a strong association between DNA methylation and re-experiencing among genocide-exposed mothers that exceeded any other observed associations by approximately two-fold.  Conclusions: This is the first report, to our knowledge, of a symptom-based analysis of transgenerational transmission of PTSD in Africa. These findings can be leveraged to inform further mechanistic and treatment research for PTSD.

Largest GWAS of PTSD (N=20 070) yields genetic overlap with schizophrenia and sex differences in heritability

The Psychiatric Genomics Consortium-Posttraumatic Stress Disorder group (PGC-PTSD) combined genome-wide case-control molecular genetic data across 11 multiethnic studies to quantify PTSD heritability, to examine potential shared genetic risk with schizophrenia, bipolar disorder, and major depressive disorder and to identify risk loci for PTSD. Examining 20 730 individuals, we report a molecular genetics-based heritability estimate (h2SNP) for European-American females of 29% that is similar to h2SNP for schizophrenia and is substantially higher than h2SNP in European-American males (estimate not distinguishable from zero). We found strong evidence of overlapping genetic risk between PTSD and schizophrenia along with more modest evidence of overlap with bipolar and major depressive disorder. No single-nucleotide polymorphisms (SNPs) exceeded genome-wide significance in the transethnic (overall) meta-analysis and we do not replicate previously reported associations. Still, SNP-level summary statistics made available here afford the best-available molecular genetic index of PTSD-for both European- and African-American individuals-and can be used in polygenic risk prediction and genetic correlation studies of diverse phenotypes. Publication of summary statistics for ∼10 000 African Americans contributes to the broader goal of increased ancestral diversity in genomic data resources. In sum, the results demonstrate genetic influences on the development of PTSD, identify shared genetic risk between PTSD and other psychiatric disorders and highlight the importance of multiethnic/racial samples. As has been the case with schizophrenia and other complex genetic disorders, larger sample sizes are needed to identify specific risk loci.

Traumatic Stress Epigenetics

Purpose of Review

Traumatic stress has profound impacts on many domains of life, yet the mechanisms that confer risk for or resilience to the development of traumatic stress-related psychopathologies are still very much under investigation. The current review highlights recent developments in the field of traumatic stress epigenetics in humans.

Recent Findings

Recent results reveal traumatic stress-related epigenetic dysregulation in neural, endocrine, and immune system genes and associated networks. Emerging work combining imaging with epigenetic measures holds promise for addressing the correspondence between peripheral and central effects of traumatic stress. A growing literature is also documenting the transgenerational effects of prenatal stress exposures in humans.

Summary

Moving forward, increasing focus on epigenetic marks of traumatic stress in CNS tissue will create a clearer picture of the relevance of peripheral measures; PTSD brain banks will help in this regard. Similarly, leveraging multigenerational birth cohort data will do much to clarify the extent of transgenerational epigenetic effects of traumatic stress. Greater efforts should be made towards developing prospective studies with longitudinal design.

Epigenetic profiles associated with major depression in the human brain

We conducted an epigenome-wide association study of Major Depressive Disorder (MDD) in brain-derived DNA using two analytic approaches. DNA methylation data (GSE41826) was used in differential methylation (DM) analyses controlling for age, sex, suicide status, and post-mortem interval; and in weighted gene co-methylation network analyses (WGCNA) in probes mapping to transcription start sites. No probes in the DM analysis survived FDR correction. Nominally significant DM probes were enriched in synaptic function-related genes. WGCNA revealed one module correlated with MDD, enriched in genes associated with mitochondrial function. DM and WGCNA both showed enrichment of genes involved in transcription and DNA binding.

FKBP5 DNA methylation does not mediate the association between childhood maltreatment and depression symptom severity in the Detroit Neighborhood Health Study

Exposure to childhood maltreatment increases the risk of developing mental illness later in life. Childhood maltreatment and depression have both been associated with dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis-a key regulator of the body's stress response. Additionally, HPA axis dysregulation has been implicated in the etiology of a range of mental illnesses. A substantial body of work has shown history of childhood maltreatment alters DNA methylation levels within key HPA axis genes. We therefore investigated whether one of these key genes, FKBP5 mediates the relationship between childhood maltreatment and depression, and assessed FKBP5 DNA methylation and gene expression within 112 adults from the Detroit Neighborhood Health Study (DNHS). DNA methylation was assessed in 4 regions, including the upstream promoter, downstream promoter, and two glucocorticoid response elements (GREs) via pyrosequencing using whole blood derived DNA; Taqman assays measured relative RNA expression from leukocytes. Mediation analyses were conducted using sequential linear regression. Childhood maltreatment was significantly associated with depression symptom severity (FDR < 0.006), but was not a significant predictor of DNA methylation in any of the four loci examined. FKBP5 showed elevated expression levels in participants with vs. without a history of depression (p < 0.001); no significant difference in gene expression levels was observed in relation to childhood maltreatment (p > 0.05). Our results suggest DNA methylation does not mediate the childhood maltreatment-depression association in the DNHS.

Pathways from assaultive violence to post-traumatic stress, depression, and generalized anxiety symptoms through stressful life events: longitudinal mediation models

BACKGROUND

Assaultive violence events are associated with increased risk for adverse psychiatric outcomes, including post-traumatic stress (PTS), depression, and generalized anxiety. Prior research has indicated that economic, legal, and social stressors that could follow assaultive events may explain the increased risk for adverse psychiatric outcomes, yet longitudinal studies have not adequately examined this pathway. In the current study, we aimed to address this limitation.

METHODS

Participants (N = 1360) were part of a longitudinal population-based study of adults living in Detroit. At three waves, participants indicated their exposure to assaultive violence and economic, legal, and social stressors, and completed inventories of PTS, depression, and generalized anxiety. Longitudinal mediation models were used to test the hypothesized pathway from assaultive violence to each psychiatric outcome.

RESULTS

The hypothesized models evidenced good fit with the data and, in each, the paths from Wave 1 (W1) assaultive violence to W2 stressors, and from W2 stressors to W3 symptoms were significant (range of Standardized Estimates: 0.09-0.15, all p < 0.01). Additionally, the indirect paths from W1 assaultive violence to W3 symptoms were significant (range of Standardized Estimates: 0.01-0.02, all p < 0.05).

CONCLUSIONS

The findings illustrate that the economic, legal, and social stressors that could follow assaultive violence increase risk for a range of psychiatric symptoms. Although future research is needed, the results suggest that investment in interventions that prevent and mitigate assaultive violence survivors' exposure to such stressors may be an effective way to prevent mental illness in the aftermath of violent assaults.

Adolescent depression linked to socioeconomic status? Molecular approaches for revealing premorbid risk factors

The means by which social environmental exposures influence risk of mental disorders is a persistent and still open question. A key candidate mechanism for the biologic mediation of environmental effects involves epigenetic factors, which regulate gene function without altering underlying DNA sequence. Recent work has shown that environmental exposures such as childhood abuse, family history of mental disorder, and low socioeconomic status (SES) associate with differential DNA methylation (5mC) - a relatively stable, but modifiable, epigenetic factor. However, the longitudinal relation among SES, 5mC, brain function, and risk of depression remains to be elucidated. Here, we briefly review literature relevant to these associations and discuss recent findings that, for the first time, prospectively demonstrate sequential links between low SES, changes in 5mC, changes in brain function, and risk of depression in a cohort of adolescents.

An in-depth look into PTSD-depression comorbidity: A longitudinal study of chronically-exposed Detroit residents

BACKGROUND

Although PTSD-major depressive disorder (MDD) co-morbidity is well-established, the vast majority of studies have examined comorbidity at the level of PTSD total severity, rather than at the level of specific PTSD symptom clusters. This study aimed to examine the long-term associations between MDD and PTSD symptom clusters (intrusion, avoidance, hyperarousal), and the moderating role of gender in these associations.

METHODS

942 residents of urban Detroit neighborhoods were interviewed at 3 waves, 1 year apart. At each wave, they were assessed for PTSD, depression, trauma exposure, and stressful life events.

RESULTS

At all waves, hyperarousal was the PTSD cluster most strongly correlated with MDD. For the full sample, a reciprocal relationship was found between MDD and all three PTSD clusters across time. Interestingly, the relative strength of associations between MDD and specific PTSD clusters changed over time. Women showed the same bidirectional MDD-PTSD pattern as in the entire sample, while men sometimes showed non-significant associations between early MDD and subsequent PTSD clusters.

LIMITATIONS

First, our analyses are based on DSM-IV criteria, as this was the existing edition at the time of this study. Second, although this is a longitudinal study, inferences regarding temporal precedence of one disorder over another must be made with caution.

CONCLUSIONS

Early identification of either PTSD or MDD following trauma may be crucial in order to prevent the development of the other disorder over time. The PTSD cluster of hyper-arousal may require special therapeutic attention. Also, professionals are encouraged to develop more gender-specific interventions post-trauma.

Glucocorticoid receptor DNA methylation, childhood maltreatment and major depression

INTRODUCTION

Altered DNA methylation (DNAm) levels of hypothalamic-pituitary-adrenal (HPA) axis genes has been associated with exposure to childhood maltreatment (CM) and depression; however, it is unknown whether CM and depression have joint and potentially interacting effects on the glucocorticoid receptor (NR3C1) DNAm. We investigated the impact of CM and lifetime major depressive disorder (MDD) on NR3C1 DNAm and gene expression (GE) in 147 adult participants from the Detroit Neighborhood Health Study.

METHODS

NR3C1 promoter region DNAm was assessed via pyrosequencing using whole blood-derived DNA. Quantitative RT-PCR assays measured GE from leukocyte-derived RNA. Linear regression models were used to examine the relationship among CM, MDD, and DNAm.

RESULTS

Both CM and MDD were significant predictors of NR3C1 DNAm: CM was associated with an increase in DNAm in an EGR1 transcription factor binding site (TFBS), whereas MDD was associated with a decrease in DNAm downstream of the TFBS. No significant CM-MDD interactions were observed. CM alone was associated with significantly lower NR3C1 GE.

LIMITATIONS

Our report of CM is a retrospective self-report of abuse, which may introduce recall bias. DNAm was measured in whole blood and may not reflect brain-derived DNAm levels.

CONCLUSIONS

CM and MDD are both associated with altered DNAm levels in the NR3C1 promoter region, however the location and direction of effects differ between the two exposures, and the functional effects, as measured by GE, appear to be limited to CM exposure alone. CM exposure may be biologically embedded in this key HPA axis gene.

Income and Markers of Immunological Cellular Aging

OBJECTIVE

Socioeconomic disadvantage may contribute to poor health through immune-related biological mechanisms. We examined the associations between socioeconomic status, as measured by annual household income, and T-cell markers of aging, including the ratios of CD4 and CD8 effector cells to naïve cells (E/N ratio) and the CD4/CD8 T-cell ratio. We hypothesized that participants with a lower income would have higher E/N ratios and lower CD4/CD8 ratios compared with participants with a higher income, and that these associations would be partially mediated by elevated cytomegalovirus (CMV) IgG antibody levels, a virus implicated in aging and clonal expansion of T cells.

METHODS

Data were from 79 individuals who participated in the population-based Detroit Neighborhood Health Study. We used linear regression to quantify the association between a $10,000 decrease in income and each ratio outcome.

RESULTS

After adjustment for age, sex, race, smoking, medication use, and lifetime history of mental health conditions, lower income was associated with a 0.41 (95% confidence interval = 0.09-0.72) log-unit increase in the CD4 E/N ratio and a 0.20 (95% confidence interval = 0.02-0.39) log-unit increase in the CD8 E/N ratio. CMV immunoglobulin G antibody level partially mediated these associations.

CONCLUSIONS

Our study suggests that low socioeconomic status is associated with immunological aging as measured by the E/N ratio and that impaired immune control of CMV may partially mediate these associations.

Study on Neurological Consequence of Eclampsia

The present study was carried out in the Department of Obstetrics and Gynecology at Mymensingh Medical College Hospital, Mymensingh, Bangladesh for a period of one year from 1st June 2009 to 30th June 2010 to see the Neurological Consequence of Eclampsia. A total number of 37 patients were enrolled in this study. Among 37 patients majority are in the age group of 21-30 years which is 19(51.4%) cases followed by less than or equal to 20 years and more than 30 years which are 13(35.1%) cases and 5(13.5%) cases respectively. Knee jerk is present in 28(75.7%) cases and absent in 8(21.6%) cases. The exaggerated knee jerk is present in only in 1(2.7%) case. The rate of Glasgow coma scale is less than 5 in 21(56.8%) cases, 14(37.8%) cases in 5-10 and 2(5.4%) cases is in more than 10. Focal sign is absent in 22(59.5%) cases and present in 15(40.5%) cases. Majority of the patients is presented with absence of neck stiffness which is 35(94.6%) cases and the rest 2(5.4%) cases are presented with neck stiffness. Flexor planter response is found in 20(54.1%) cases which is the highest in number followed by extensor which is 15(40.5%) cases. In only 2(5.4%) cases the planter reflex is not elicitable. Presence of infarct is found in 15(40.5%) cases which is the highest number. Cerebral edema and Presence of haemorrhage is found in 3(8.1%) cases in each. Leuko-encephalopathy is found in 2(5.4%) cases. Encephalopathy and Both infarct & haemorrhage is found in 1(2.7%) case of each. Normal CT scan findings of brain are found in 12(32.4%) cases.

Reconstructing three-dimensional helical structure with an X-ray free electron laser

Recovery of three-dimensional structure from single-particle X-ray scattering of completely randomly oriented diffraction patterns as predicted a few decades ago has been realized owing to the advent of the new emerging X-ray free electron laser (XFEL) technology. Since the world's first XFEL started operation in June 2009 at SLAC National Laboratory at Stanford, the first few experiments have been conducted on larger objects such as viruses. Many of the important structures of nature such as helical viruses or DNA consist of helical repetition of biological subunits. Hence development of a method for reconstructing helical structure from collected XFEL data has been a top research priority. This work describes the development of a method for solving helical structures such as tobacco mosaic virus from a set of randomly oriented simulated diffraction patterns exploiting the symmetry and Fourier space constraint of the diffraction volume.

Overexpression of sonic hedgehog in the triple negative breast cancer: clinicopathological characteristics of high burden breast cancer patients from Bangladesh

Dysregulation of Hedgehog (Hh) signaling pathway has been documented in mammary gland development and breast cancer (BC) progression. Despite the remarkable progress in therapeutic interventions, BC related mortality in Bangladesh increased in the last decade. Triple negative breast cancer (TNBC) still presents a critical therapeutic challenge. Thus effective targeted therapy is urgently needed. In this study, we report the clinicopathological characteristics and prognosis of BC patients from Bangladesh. Routine immunohistochemical analysis and high throughput RNA-Seq data from the TCGA library were used to analyze the expression pattern and association of high and low level of Shh expression in a collection of BC patients with a long-term follow-up. High levels of Shh were observed in a subset of BC tumors with poor prognostic pathological features. Higher level of Shh expression correlated with a significantly poorer overall survival of patients compared with patients whose tumors expressed a low level of Shh. These data support the contention that Shh could be a novel biomarker for breast cancer that is involved in mediating the aggressive phenotype of BC. We propose that BC patients exhibiting a higher level of Shh expression, representing a subset of BC patients, would be amenable to Shh targeted therapy.

Population Distributions of Thymic Function in Adults: Variation by Sociodemographic Characteristics and Health Status

The thymus is critical for mounting an effective immune response and maintaining health. However, epidemiologic studies characterizing thymic function in the population setting are lacking. Using data from 263 adults in the Detroit Neighborhood Health Study, we examined thymic function as measured by the number of signal joint T-cell receptor excision circles (sjTREC) and assessed associations with established indicators of physiological health. Overall, increasing age and male gender were significantly associated with reduced thymic function. Adjusting for covariates, individuals with elevated levels of the pro-inflammatory biomarkers C-reactive protein (β: -0.50 [95% CI: -0.82, -0.18] for moderate elevation, β: -0.29 [95% CI: -0.59, 0.00] for high elevation) and interleukin-6 (β: -0.60 [95% CI: -0.92, -0.28] for moderate elevation, β: -0.43 [95% CI: -0.77, -0.08] for severe elevation) also had lower thymic function. Compared to individuals with a BMI < 25, individuals who were overweight (β: 0.36 [95% CI: 0.07, 0.64]) or obese (β: 0.27 [95% CI: -0.03, 0.56]) had higher thymic function. Differences by self-rated health were not statistically significant. Our findings underscore demographic- and health-related gradients in thymic function among adult residents of Detroit, suggesting thymic function may be an important biomarker of health status in adults at the population level.