The neurophysiological consequences of racism-related stressors in Black Americans.

Racism-related stressors, from experiences of both implicit and explicit racial discrimination to systemic socioeconomic disadvantage, have a cumulative impact on Black Americans' health. The present narrative review synthesizes peripheral (neuroendocrine and inflammation markers), psychophysiological (heart-rate variability, skin conductance), and neuroimaging (structural and functional) findings that demonstrate unique associations with racism-related stress. Emerging evidence reveals how racism-related stressors contribute to differential physiological and neural responses and may have distinct impacts on regions involved with threat and social processing. Ultimately, the neurophysiological effects of racism-related stress may confer biological susceptibility to stress and trauma-related disorders. We note critical gaps in the literature on the neurophysiological impact of racism-related stress and outline additional research that is needed on the multifactorial interactions between racism and mental health. A clearer understanding of the interactions between racism-related stress, neurophysiology, and stress- and trauma-related disorders is critical for preventative efforts, biomarker discovery, and selection of effective clinical treatments for Black Americans.

Racial Disparities in Adversity During Childhood and the False Appearance of Race-Related Differences in Brain Structure.

OBJECTIVE: Black Americans in the United States are disproportionately exposed to childhood adversity compared with White Americans. Such disparities may contribute to race-related differences in brain structures involved in regulating the emotional response to stress, such as the amygdala, hippocampus, and prefrontal cortex (PFC). The authors investigated neuroanatomical consequences of racial disparities in adversity. METHODS: The sample included 7,350 White American and 1,786 Black American children (ages 9-10) from the Adolescent Brain Cognitive Development Study (public data release 2.0). Structural MRI data, parent and child self-reports of adversity-related measures, and U.S. Census neighborhood data were used to investigate the relationship between racial disparities in adversity exposure and race-related differences in brain structure. RESULTS: Black children experienced more traumatic events, family conflict, and material hardship on average compared with White children, and their parents or caregivers had lower educational attainment, lower income, and more unemployment compared with those of White children. Black children showed lower amygdala, hippocampus, and PFC gray matter volumes compared with White children. The volumes of the PFC and amygdala, but not the hippocampus, also varied with metrics of childhood adversity, with income being the most common predictor of brain volume differences. Accounting for differences in childhood adversity attenuated the magnitude of some race-related differences in gray matter volume. CONCLUSIONS: The results suggest that disparities in childhood adversity contribute to race-related differences in gray matter volume in key brain regions associated with threat-related processes. Structural alterations of these regions are linked to cognitive-affective dysfunction observed in disorders such as posttraumatic stress disorder. More granular assessments of structural inequities across racial/ethnic identities are needed for a thorough understanding of their impact on the brain. Together, the present findings may provide insight into potential systemic contributors to disparate rates of psychiatric disease among Black and White individuals in the United States.

Utility of Wrist-Wearable Data for Assessing Pain, Sleep, and Anxiety Outcomes After Traumatic Stress Exposure.

Importance: Adverse posttraumatic neuropsychiatric sequelae after traumatic stress exposure are common and have higher incidence among socioeconomically disadvantaged populations. Pain, depression, avoidance of trauma reminders, reexperiencing trauma, anxiety, hyperarousal, sleep disruption, and nightmares have been reported. Wrist-wearable devices with accelerometers capable of assessing 24-hour rest-activity characteristics are prevalent and may have utility in measuring these outcomes. Objective: To evaluate whether wrist-wearable devices can provide useful biomarkers for recovery after traumatic stress exposure. Design, Setting, and Participants: Data were analyzed from a diverse cohort of individuals seen in the emergency department after experiencing a traumatic stress exposure, as part of the Advancing Understanding of Recovery After Trauma (AURORA) study. Participants recruited from 27 emergency departments wore wrist-wearable devices for 8 weeks, beginning in the emergency department, and completed serial assessments of neuropsychiatric symptoms. A total of 19 019 patients were screened. Of these, 3040 patients met study criteria, provided informed consent, and completed baseline assessments. A total of 2021 provided data from wrist-wearable devices, completed the 8-week assessment, and were included in this analysis. The data were randomly divided into 2 equal parts (n = 1010) for biomarker identification and validation. Data were collected from September 2017 to January 2020, and data were analyzed from May 2020 to November 2022. Exposures: Participants were recruited for the study after experiencing a traumatic stress exposure (most commonly motor vehicle collision). Main Outcomes and Measures: Rest-activity characteristics were derived and validated from wrist-wearable devices associated with specific self-reported symptom domains at a point in time and changes in symptom severity over time. Results: Of 2021 included patients, 1257 (62.2%) were female, and the mean (SD) age was 35.8 (13.0) years. Eight wrist-wearable device biomarkers for symptoms of adverse posttraumatic neuropsychiatric sequelae exceeded significance thresholds in the derivation cohort. One of these, reduced 24-hour activity variance, was associated with greater pain severity (r = -0.14; 95% CI, -0.20 to -0.07). Changes in 6 rest-activity measures were associated with changes in pain over time, and changes in the number of transitions between sleep and wake over time were associated with changes in pain, sleep, and anxiety. Simple cutoffs for these biomarkers identified individuals with good recovery for pain (positive predictive value [PPV], 0.85; 95% CI, 0.82-0.88), sleep (PPV, 0.63; 95% CI, 0.59-0.67, and anxiety (PPV, 0.76; 95% CI, 0.72-0.80) with high predictive value. Conclusions and Relevance: These findings suggest that wrist-wearable device biomarkers may have utility as screening tools for pain, sleep, and anxiety symptom outcomes after trauma exposure in high-risk populations.

Racial Discrimination and White Matter Microstructure in Trauma-Exposed Black Women.

BACKGROUND: Experiences of racial discrimination are linked to a range of negative brain health outcomes, but little is known about how these experiences impact neural architecture, including white matter microstructure, which may partially mediate these outcomes. Our goal was to examine associations between racially discriminatory experiences and white matter structural integrity in a sample of Black American women. METHODS: We recruited 116 Black American women as part of a long-standing study of trauma. Participants completed assessments of racial discrimination, trauma exposure, and posttraumatic stress disorder and underwent diffusion tensor imaging. Fractional anisotropy and mean diffusivity values were extracted from major white matter tracts throughout the brain. RESULTS: Experiences of racial discrimination were associated with significantly lower fractional anisotropy in multiple white matter tracts, including the corpus callosum, cingulum, and superior longitudinal fasciculus (ps < .004), even after accounting for variance associated with trauma, posttraumatic stress disorder, and demographic- and scanner-related factors. CONCLUSIONS: These findings suggest that experiences of racial discrimination are independently related to decrements in white matter microarchitecture throughout the brain. In individuals who have experienced other types of adversity, racial discrimination clearly has additive and distinctive deleterious effects on white matter structure. Our findings suggest a pathway through which racial discrimination can contribute to brain health disparities in Black Americans; the deleterious contributions of racial discrimination on the microstructure of major white matter pathways may increase vulnerability for the development of neurodegenerative disorders as well as the development of mental health problems.

Social cognition or social class and culture? On the interpretation of differences in social cognitive performance.

BACKGROUND: The ability to understand others' mental states carries profound consequences for mental and physical health, making efforts at validly and reliably assessing mental state understanding (MSU) of utmost importance. However, the most widely used and current NIMH-recommended task for assessing MSU - the Reading the Mind in the Eyes Task (RMET) - suffers from potential assessment issues, including reliance on a participant's vocabulary/intelligence and the use of culturally biased stimuli. Here, we evaluate the impact of demographic and sociocultural factors (age, gender, education, ethnicity, race) on the RMET and other social and non-social cognitive tasks in an effort to determine the extent to which the RMET may be unduly influenced by participant characteristics. METHODS: In total, 40 248 international, native-/primarily English-speaking participants between the ages of 10 and 70 completed one of five measures on TestMyBrain.org: RMET, a shortened version of RMET, a multiracial emotion identification task, an emotion discrimination task, and a non-social/non-verbal processing speed task (digit symbol matching). RESULTS: Contrary to other tasks, performance on the RMET increased across the lifespan. Education, race, and ethnicity explained more variance in RMET performance than the other tasks, and differences between levels of education, race, and ethnicity were more pronounced for the RMET than the other tasks such that more highly educated, non-Hispanic, and White/Caucasian individuals performed best. CONCLUSIONS: These data suggest that the RMET may be unduly influenced by social class and culture, posing a serious challenge to assessing MSU in clinical populations given shared variance between social status and psychiatric illness.

Mobile assessment of heightened skin conductance in posttraumatic stress disorder.

BACKGROUND: Increased psychophysiological reactivity is a hallmark intermediate phenotype of posttraumatic stress disorder (PTSD). Individuals with PTSD exhibit greater skin conductance (SC) responses to trauma scripts than trauma survivors without PTSD. However, trauma scripts require time for development and cannot be easily used in a single visit. Thus, there is a need for a low-cost, easy-to-use, SC recording protocol for PTSD assessment. METHODS: Using a mobile device (eSense) connected to a portable tablet computer, we assessed SC reactivity to a standard trauma interview (STI) in 63 participants recruited from Grady Memorial Hospital in Atlanta, GA, approximately 1 year after trauma exposure. SC response (SCR) was calculated by subtracting the SC level (SCL) at the end of the baseline recording from the maximum SCL during the STI. RESULTS: SCL was significantly higher during the STI compared to baseline (P < .001), and individuals with PTSD showed significantly greater SCR than individuals without PTSD (P = .006). Logistic regression using SCR with PTSD diagnosis as the outcome showed an odds ratio of 1.76 (95% CI: 1.11-2.78). Lastly, higher SCR during the STI was also significantly associated with PTSD symptom total score controlling for demographics and trauma severity (b = 0.42, P = .001). CONCLUSIONS: The current study demonstrated feasibility of the use of a mobile device for assessing psychophysiological reactivity in those with PTSD. The use of this low-cost, easy-to-use mobile device to collect objective physiological data in concert with a STI can be easily disseminated in clinical and research settings.

Cross-cultural gene- environment interactions in depression, post-traumatic stress disorder, and the cortisol awakening response: FKBP5 polymorphisms and childhood trauma in South Asia.

Despite increased attention to global mental health, psychiatric genetic research has been dominated by studies in high-income countries, especially with populations of European descent. The objective of this study was to assess single nucleotide polymorphisms (SNPs) in the FKBP5 gene in a population living in South Asia. Among adults in Nepal, depression was assessed with the Beck Depression Inventory (BDI), post-traumatic stress disorder (PTSD) with the PTSD Checklist-Civilian Version (PCL-C), and childhood maltreatment with the Childhood Trauma Questionnaire (CTQ). FKBP5 SNPs were genotyped for 682 participants. Cortisol awakening response (CAR) was assessed in a subsample of 118 participants over 3 days. The FKBP5 tag-SNP rs9296158 showed a main effect on depressive symptoms (p = 0.03). Interaction of rs9296158 and childhood maltreatment predicted adult depressive symptoms (p = 0.02) but not PTSD. Childhood maltreatment associated with endocrine response in individuals homozygous for the A allele, demonstrated by a negative CAR and overall hypocortisolaemia in the rs9296158 AA genotype and childhood maltreatment group (p < 0.001). This study replicated findings related to FKBP5 and depression but not PTSD. Gene-environment studies should take differences in prevalence and cultural significance of phenotypes and exposures into account when interpreting cross-cultural findings.

The renin-angiotensin pathway in posttraumatic stress disorder: angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are associated with fewer traumatic stress symptoms.

OBJECTIVE: Posttraumatic stress disorder (PTSD) is a debilitating stress-related illness associated with trauma exposure. The peripheral and central mechanisms mediating stress response in PTSD are incompletely understood. Recent data suggest that the renin-angiotensin pathway, essential to cardiovascular regulation, is also involved in mediating stress and anxiety. In this study, the authors examined the relationship between active treatment with blood pressure medication, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), and PTSD symptom severity within a highly traumatized civilian medical population. METHOD: Cross-sectional, observational data were analyzed from a larger study; patients were recruited from Grady Memorial Hospital's outpatient population from 2006 to November 2010. Multivariable linear regression models were fit to statistically evaluate the independent association of being prescribed an ACE inhibitor or ARB with PTSD symptoms, using a subset of patients for whom medical information was available (n = 505). Categorical PTSD diagnosis was assessed using the modified PTSD Symptom Scale (PSS) based on DSM-IV criteria, and PTSD symptom severity (the primary outcome of interest) was measured using the PSS and Clinician Administered PTSD Scale. RESULTS: A significant association was determined between presence of an ACE inhibitor/ARB medication and decreased PTSD symptoms (mean PSS score 11.4 vs 14.9 for individuals prescribed vs not prescribed ACE inhibitors/ARBs, respectively [P = .014]). After adjustment for covariates, ACE inhibitor/ARB treatment remained significantly associated with decreased PTSD symptoms (P = .044). Notably, other blood pressure medications, including ß-blockers, calcium channel blockers, and diuretics, were not significantly associated with reduced PTSD symptoms. CONCLUSIONS: These data provide the first clinical evidence supporting a role for the renin-angiotensin system in the regulation of stress response in patients diagnosed with PTSD. Further studies should examine whether available medications targeting this pathway should be considered for future treatment and potential protection against PTSD symptoms.

Posttraumatic stress disorder is a risk factor for metabolic syndrome in an impoverished urban population.

OBJECTIVE: Metabolic syndrome is associated with elevated risk for cardiovascular disease and diabetes and has increased prevalence in low-income African Americans, which constitutes a significant health disparity. The mechanisms responsible for this disparity remain unclear; the current study investigated the relationship between posttraumatic stress disorder (PTSD) and metabolic syndrome. METHOD: We assessed childhood and adult trauma history, major depressive disorder, PTSD and the components of metabolic syndrome in an urban population. We recruited 245 low-socioeconomic-status, primarily African American subjects from general medical clinics in an inner-city hospital. RESULTS: Trauma exposure was extremely prevalent, with 90.6% of subjects reporting at least one significant trauma and 18.8% of subjects meeting criteria for current PTSD. Metabolic syndrome was also prevalent in this population (33.2%), with significantly higher rates among patients with current PTSD (47.8%, P<.05). After controlling for demographics, smoking history, antipsychotic use, depression and exercise, current PTSD remained the only significant predictor of metabolic syndrome (P=.006). CONCLUSIONS: PTSD is associated with increased rates of metabolic syndrome within a traumatized, impoverished urban population. Further studies should investigate if PTSD treatment may reduce the rates of metabolic syndrome, improve overall health outcomes and decrease health care disparities in minority populations.