High early life stress and aberrant amygdala activity: risk factors for elevated neuropsychiatric symptoms in HIV+ adults

Alexithymia Among People Living with HIV: A Scoping Review

The present scoping review aimed to identify studies that investigated alexithymia, defined as a difficulty in identifying and describing one's own emotions, in people living with HIV (PLWH).A literature search, in line with the guidelines of PRISMA-ScR, was conducted in the following bibliographic databases: PubMed, PsycINFO, and Web of Science. The databases were queried using the following strings (using Boolean operators): ("alexithymia" OR "alexithymic") AND ("HIV" OR "Human Immunodeficiency Virus"). In line with the eligibility criteria, fourteen articles were found.Ten studies showed the involvement of alexithymia in disease severity (e.g., viral load levels), and adherence to antiretroviral therapy. Three studies revealed an association between alexithymia and cardiovascular disease, and three studies highlighted the implication of alexithymia in cognitive impairment.This review revealed the complex role of alexithymia in HIV disease. A careful clinical assessment of the emotional regulation process of PLWH can provide useful prognostic information.

Synergistic effects of high early-life stress exposure and HIV infection on reaction time variability

Addressing comorbidities contributing to cognitive impairment in people living with HIV (PLWH) remains imperative. Prior studies utilizing reaction time intra-individual variability (RT-IIV), a robust behavioral marker of cognitive dysfunction, demonstrate increased cognitive impairment in adults living with HIV who have high early life stress (ELS) exposure relative to those with low-ELS exposure. Yet, it is unknown whether RT-IIV elevations are due to high-ELS alone or both HIV-status and high-ELS. In the current study, we explore the potential additive effects of HIV and high-ELS exposure on RT-IIV to better characterize the independent and combined effects of these factors on RT-IIV among PLWH. We assessed 59 PLWH and 69 HIV-negative healthy control (HC) participants with either low or high ELS on RT-IIV during a working memory task (1-back). We observed a significant interaction between HIV status and ELS exposure on RT-IIV, PLWH who had experienced high ELS demonstrating RT-IIV elevations relative to all other groups. In addition, RT-IIV was significantly associated with ELS exposure in PLWH, but not in the HC group. We also observed associations between RT-IIV and measures of HIV-disease severity (plasma HIV viral load, nadir CD4) among PLWH. Taken as a whole, these findings provide novel evidence of the combined effects of HIV and high-ELS exposure on RT-IIV, and thus suggest HIV-related and ELS-related neural abnormalities may act in an additive or synergistic manner to affect cognition. Such data warrant further investigation into the neurobiological mechanisms associated with HIV and high-ELS exposure that contribute to increased neurocognitive dysfunction among PLWH.

Effects of Early-Life Adversities on Neuropsychiatric and Executive Functions in HIV-Positive Adults

OBJECTIVE

Adverse childhood experiences (ACEs) contribute to elevations in neuropsychiatric and neurocognitive symptoms in HIV+ adults. Emerging data suggest that exposures to threat-related and deprivation-related ACEs may have differential impacts on function, with threat exposure contributing to neuropsychiatric symptoms, and deprivation contributing to executive dysfunction. Yet, it remains unclear how specific types of ACEs impact neuropsychiatric and neurocognitive symptoms in HIV+ adults. Hence, the current study examined whether these two dimensions of adversity contribute differentially to neuropsychiatric symptoms and executive dysfunction in HIV+ adults.

METHODS

We included a sample of demographically matched HIV+ (N = 72) and HIV-negative (N = 85) adults. Standardized self-report measures assessed threat-related (interpersonal violence) and deprivation-related (poverty/neglect) ACEs, as well as neuropsychiatric symptoms (depression, anxiety, apathy). A brief battery of neuropsychological tests assessed executive functions.

RESULTS

Compared to HIV-negative participants, HIV+ participants reported significantly higher rates of threat exposure (51% vs. 67%, p = .04), while rates of deprivation did not differ significantly (8% vs. 13%, p = .38). In the HIV+ sample, threat exposure was associated with neuropsychiatric symptoms (p < .01) but not executive dysfunction (p = .75). By contrast, deprivation was associated with executive dysfunction, at a trend level (p = .09), but not with neuropsychiatric symptoms (p = .70).

CONCLUSIONS

Our data suggest that, relative to HIV-negative samples, HIV+ samples experience higher rates of threat-related ACEs, which contribute to neuropsychiatric symptom elevations. Moreover, our preliminary findings suggest that different types of ACEs could be associated with different profiles of neuropsychiatric and neurocognitive difficulty in HIV+ adults, highlighting the importance of considering dimensions of adversity in future studies.

Neuropsychiatric Disorders, Emotional Disturbances, and Their Associations with HIV-Associated Neurocognitive Disorder

The current chapter provides a critical and narrative review of recent research on the neuropsychiatric disorders, emotional disturbances, and their associations with neurocognitive functioning in people living with HIV infection. We review a range of neuropsychiatric disorders including depression and anxiety disorders, but also emotional disturbances, which can be partly distinguished from depression and anxiety (apathy, alexithymia, and emotional processing impairment). While reviewing the research into the neuropsychiatric disorders and HIV-associated neurocognitive disorders, we also cover the questions of self-reported cognitive symptoms evaluation and interpretation. The chapter includes research on the role of coping skills, perceived stress and response to stressful life events, and connections to neurocognitive impairment in people living with HIV. Promising non-pharmacological interventions are highlighted. The chapter concludes with the clinical implications on how to best consider neuropsychiatric disorders and cognitive symptoms for the diagnosis of HIV-associated neurocognitive disorders, as well as future research directions.

Efficacy, safety and central nervous system effects after switch from efavirenz/tenofovir/emtricitabine to doravirine/tenofovir/lamivudine

OBJECTIVE

Doravirine is an alternative treatment option for individuals who do not tolerate efavirenz. We assessed efficacy, safety, and CNS effects in adults with HIV-1 and CNS complaints who switched from an efavirenz-based regimen to a doravirine-based regimen.

DESIGN

Multicenter, double-blind, randomized trial (NCT02652260).

METHODS

Virologically suppressed adults receiving efavirenz/emtricitabine/tenofovir (EFV/FTC/TDF), or its components, with ongoing EFV-associated CNS toxicity grade 2 or higher (DAIDS criteria) were switched to doravirine/lamivudine/tenofovir (DOR/3TC/TDF) on day 1 (Immediate Switch Group [ISG]) or after 12 weeks (Deferred Switch Group [DSG]). CNS toxicity data were collected by self-administered questionnaire. The primary endpoint was the proportion of participants with any grade 2 or higher CNS toxicity at week 12. Secondary endpoints included virologic response and effect on fasting lipids.

RESULTS

Eighty-six participants (58% men, 56% black, median age 41 years, median 4 years on prior EFV regimen) were enrolled (43 ISG, 43 DSG) and included in the analyses. At week 12, 42% of ISG and 37% of DSG had at least 1 grade 2 or higher CNS toxicity [difference 4.7%, 95% CI (-16 to 25%); P = 0.33]. At 24 weeks postswitch, HIV-1 RNA less than 50 copies/ml was maintained in 95.3% of participants, and fasting lipids were significantly decreased (LDL-cholesterol -11.0, non-HDL-cholesterol -13.2, HDL-cholesterol -7.7, total cholesterol -20.9, and triglycerides -13.0 mg/dl).

CONCLUSION

In participants who had CNS complaints while receiving EFV/FTC/TDF, improvement in CNS toxicities attributable to EFV was not significantly different after switching to DOR/3TC/TDF compared with remaining on EFV/FTC/TDF. Virologic efficacy was maintained and lipid profiles improved after switching to DOR/3TC/TDF.

Mini-review: Elucidating the psychological, physical, and sex-based interactions between HIV infection and stress

Stress is generally classified as any mental or emotional strain resulting from difficult circumstances, and can manifest in the form of depression, anxiety, post-traumatic stress disorder (PTSD), or other neurocognitive disorders. Neurocognitive disorders such as depression, anxiety, and PTSD are large contributors to disability worldwide, and continue to affect individuals and communities. Although these disorders affect men and women, women are disproportionately represented among those diagnosed with affective disorders, a result of both societal gender roles and physical differences. Furthermore, the incidence of these neurocognitive disorders is augmented among People Living with HIV (PLWH); the physical ramifications of stress increase the likelihood of HIV acquisition, pathogenesis, and treatment, as both stress and HIV infection are characterized by chronic inflammation, which creates a more opportunistic environment for HIV. Although the stress response is facilitated by the autonomic nervous system (ANS) and the hypothalamic pituitary adrenal (HPA) axis, when the response involves a psychological component, additional brain regions are engaged. The impact of chronic stress exposure and the origin of individual variation in stress responses and resilience are at least in part attributable to regions outside the primary stress circuity, including the amygdala, prefrontal cortex, and hippocampus. This review aims to elucidate the relationship between stress and HIV, how these interact with sex, and to understand the physical ramifications of these interactions.

Plasma anti-CD4 IgG is associated with brain abnormalities in people with HIV on antiretroviral therapy

Anti-CD4 IgG autoantibodies have been implicated in CD4⁺ T cell reconstitution failure, leaving people with HIV (PWH) at heightened risk of HIV-associated comorbidities, such as neurocognitive impairment. Seventeen PWH on stable anti-retroviral therapy (ART) and 10 HIV seronegative controls had plasma anti-CD4 IgG antibodies measured by enzyme-linked immunosorbent assay. Neuropsychological (NP) tests assessed cognitive performance, and brain volumes were measured by structural magnetic resonance imaging. Anti-CD4 IgG levels were elevated (p = 0.04) in PWH compared with controls. Anti-CD4 IgG correlated with global NP z-scores (rho = - 0.51, p = 0.04). A relationship was observed between anti-CD4 IgG and putamen (β = - 0.39, p = 0.02), pallidum (β = - 0.38, p = 0.03), and amygdala (β = - 0.42, p = 0.05) regional brain volumes. The results of this study suggest the existence of an antibody-mediated relationship with neurocognitive impairment and brain abnormalities in an HIV-infected population.

Early Adversity and Emotion Processing From Faces: A Meta-analysis on Behavioral and Neurophysiological Responses

BACKGROUND

Although the link between early adversity (EA) and later-life psychiatric disorders is well established, it has yet to be elucidated whether EA is related to distortions in the processing of different facial expressions. We conducted a meta-analysis to investigate whether exposure to EA relates to distortions in responses to different facial emotions at three levels: 1) event-related potentials of the P100 and N170, 2) amygdala functional magnetic resonance imaging responses, and 3) accuracy rate or reaction time in behavioral data.

METHODS

The systematic literature search (PubMed and Web of Science) up to April 2020 resulted in 29 behavioral studies (n = 8555), 32 functional magnetic resonance imaging studies (n = 2771), and 3 electroencephalography studies (n = 197) for random-effect meta-analyses.

RESULTS

EA was related to heightened bilateral amygdala reactivity to sad faces (but not other facial emotions). Exposure to EA was related to faster reaction time but a normal accuracy rate in response to angry and sad faces. In response to fearful and happy faces, EA was related to a lower accuracy rate only in individuals with recent EA exposure. This effect was more pronounced in individuals with exposure to EA before (vs. after) the age of 3 years. These findings were independent of psychiatric diagnoses. Because of the low number of eligible electroencephalography studies, no conclusions could be reached regarding the effect of EA on the event-related potentials.

CONCLUSIONS

EA relates to alterations in behavioral and neurophysiological processing of facial emotions. Our study stresses the importance of assessing age at exposure and time since EA because these factors mediate some EA-related perturbations.

Neurobehavioral outcomes in young adults with perinatally acquired HIV

BACKGROUND

With combination antiretroviral therapy (cART), infants with perinatally acquired HIV (pHIV) are living into adolescence and adulthood. Worldwide, many have not received cART in the first years of life, and challenges of adolescence complicate transition to adulthood. Neurobehavioral outcomes in pHIV young adults (pHIVAd) are infrequently reported.

OBJECTIVES

To examine neurobehavioral characteristics of pHIVAd ages 21-30 years, and to compare them with age-matched young adults infected in the second or third decade of life (HIVagematch), and older adults with similar duration HIV disease (HIVOA).

METHODS

A comprehensive neuropsychological test battery and questionnaires to determine cognitive function and mood, and reviews of neuromedical and behavioral records were undertaken in three groups of 13 individuals each. Descriptive analysis and bivariate techniques were used for comparisons.

RESULTS

Rates of cognitive impairment were highest in pHIVAd (85%) compared with HIVagematch (38%) and HIVOA (62%). pHIVAd had the worst scores in global cognition, speed of information processing, working memory, and verbal fluency (0.5--1.0 SD below other groups). There was a trend for higher rates of psychiatric dysfunction (predominantly mood disorders) in pHIVAd (85%) compared with HIV-agematch (46%) and HIVOA (54%). Only four pHIVAd reported employment or enrollment in school. Four had autoimmune disorders.

CONCLUSION

These pHIVAd displayed high rates of cognitive, psychiatric, and autoimmune dysfunction, greater than age-matched or HIV duration-matched comparators. Although this small study is largely descriptive in nature, it suggests that a lack of cART in early life may result in long-term neurobehavioral and immune abnormalities manifesting into adulthood.

Resting-state neural signatures of depressive symptoms in acute HIV

Depressive symptoms are often elevated in acute and chronic HIV. Previous neuroimaging research identifies abnormalities in emotion-related brain regions in depression without HIV, including the anterior cingulate cortex (ACC) and amygdala. However, no studies have examined the neural signatures of depressive symptoms in acute HIV infection (AHI). Seed-based voxelwise resting-state functional connectivity (rsFC) for affective seed regions of interest (pregenual ACC, subgenual ACC [sgACC], bilateral amygdala) was computed for 74 Thai males with AHI and 30 Thai HIV-uninfected controls. Group analyses compared rsFC of ACC and amygdala seed regions between AHI and uninfected control groups. Within the AHI group, voxelwise regression analyses investigated the relationship between depressive symptoms and rsFC for these affective seed regions. Group analyses revealed alterations in rsFC of the amygdala in AHI versus uninfected controls. Depressive symptoms associated with decreased rsFC between ACC regions and posterior cingulate/precuneus, medial temporal, and lateral parietal regions in AHI. Symptoms of depression also correlated to increased rsFC between ACC regions and lateral prefrontal cortex, sgACC, and cerebellum in AHI. Similar to the ACC, depressive symptoms associated with decreased rsFC between amygdala and precuneus. Of blood biomarkers, only HIV RNA inversely correlated with rsFC between posterior sgACC and left uncus. We found that depressive symptoms in AHI associate with altered rsFC of ACC and amygdala regions previously implicated in depression. Longitudinal research in this cohort will be necessary to determine whether these early alterations in rsFC of affective network regions are related to persistent depressive symptoms after combination antiretroviral therapy.

The Mediating Role of Neural Activity on the Relationship Between Childhood Maltreatment and Impulsivity

Child maltreatment is associated with a variety of risk behaviors in young adulthood; however, the underlying cognitive and neural mechanisms of this relation are not well understood. The primary aim of the present study was to examine the direct and indirect effects between maltreatment in childhood and downstream impulsivity via neural activity during a cognitive task. In a sample of emerging adult women from the rural southeastern United States, childhood abuse and neglect were assessed using the childhood trauma questionnaire. Outcome measures of neural activity during a functional magnetic resonance imaging N-back verbal working memory (WM) task and trait impulsivity on the Impulsive Behavior Scale were assessed approximately 1 year later. Results indicate that adults with higher levels of reported childhood maltreatment demonstrate worse behavioral performance and lower neural response during a difficult verbal WM task. Furthermore, neural activity significantly mediated the relation between abuse and neglect in childhood and trait impulsivity. These new findings demonstrate an association between neurocognitive functioning and reported childhood abuse and neglect, and indicate that such changes may underlie the relation between maltreatment and trait-level impulsivity.

Early Life Stress and Epigenetics in Late-onset Alzheimer's Dementia: A Systematic Review

Involvement of life stress in Late-Onset Alzheimer's Disease (LOAD) has been evinced in longitudinal cohort epidemiological studies, and endocrinologic evidence suggests involvements of catecholamine and corticosteroid systems in LOAD. Early Life Stress (ELS) rodent models have successfully demonstrated sequelae of maternal separation resulting in LOAD-analogous pathology, thereby supporting a role of insulin receptor signalling pertaining to GSK-3beta facilitated tau hyper-phosphorylation and amyloidogenic processing. Discussed are relevant ELS studies, and findings from three mitogen-activated protein kinase pathways (JNK/SAPK pathway, ERK pathway, p38/MAPK pathway) relevant for mediating environmental stresses. Further considered were the roles of autophagy impairment, neuroinflammation, and brain insulin resistance. For the meta-analytic evaluation, 224 candidate gene loci were extracted from reviews of animal studies of LOAD pathophysiological mechanisms, of which 60 had no positive results in human LOAD association studies. These loci were combined with 89 gene loci confirmed as LOAD risk genes in previous GWAS and WES. Of the 313 risk gene loci evaluated, there were 35 human reports on epigenomic modifications in terms of methylation or histone acetylation. 64 microRNA gene regulation mechanisms were published for the compiled loci. Genomic association studies support close relations of both noradrenergic and glucocorticoid systems with LOAD. For HPA involvement, a CRHR1 haplotype with MAPT was described, but further association of only HSD11B1 with LOAD found; however, association of FKBP1 and NC3R1 polymorphisms was documented in support of stress influence to LOAD. In the brain insulin system, IGF2R, INSR, INSRR, and plasticity regulator ARC, were associated with LOAD. Pertaining to compromised myelin stability in LOAD, relevant associations were found for BIN1, RELN, SORL1, SORCS1, CNP, MAG, and MOG. Regarding epigenetic modifications, both methylation variability and de-acetylation were reported for LOAD. The majority of up-to-date epigenomic findings include reported modifications in the well-known LOAD core pathology loci MAPT, BACE1, APP (with FOS, EGR1), PSEN1, PSEN2, and highlight a central role of BDNF. Pertaining to ELS, relevant loci are FKBP5, EGR1, GSK3B; critical roles of inflammation are indicated by CRP, TNFA, NFKB1 modifications; for cholesterol biosynthesis, DHCR24; for myelin stability BIN1, SORL1, CNP; pertaining to (epi)genetic mechanisms, hTERT, MBD2, DNMT1, MTHFR2. Findings on gene regulation were accumulated for BACE1, MAPK signalling, TLR4, BDNF, insulin signalling, with most reports for miR-132 and miR-27. Unclear in epigenomic studies remains the role of noradrenergic signalling, previously demonstrated by neuropathological findings of childhood nucleus caeruleus degeneration for LOAD tauopathy.

Resting-state connectivity and spontaneous activity of ventromedial prefrontal cortex predict depressive symptomology and peripheral inflammation in HIV

Depression and chronic inflammation are common in persons infected with the human immunodeficiency virus (HIV+). Although depression and response to inflammatory challenge are shown to reflect activity in common neural networks, little is known regarding sub-clinical presentation in persons chronically infected with HIV. The relationship of resting-state functional connectivity (rsFC) between the subgenual anterior cingulate cortex (sgACC) and bilateral amygdala to Beck Depression Inventory-1 (BDI) scores were compared within a group of 23 HIV+ and 23 HIV-negative comparison adults. An interaction was found wherein lower rsFC between the sgACC and both right and left amygdala was associated with higher BDI scores in HIV+ individuals. Total BDI scores and plasma levels of IL-6, IL-8, TNF-α, and IL-10 made available from 10 of the HIV+ patients were regressed upon an index of spontaneous whole-brain activity at rest; i.e., the amplitude of low-frequency fluctuations (ALFFs). Elevated levels of depression and IL-6 were associated with increased ALFF in a cluster of voxels on the medial portion of the ventral surface of the frontal lobe (Brodmann Area 11). Within this sample of HIV+ individuals lower rsFC of the sgACC with subcortical limbic regions predicts greater burden of depressive symptomology whereas elevated activity in the adjacent BA 11 may reflect sickness, indexed by elevated IL-6, and associated depressive behaviors.

EcoHIV infection of mice establishes latent viral reservoirs in T cells and active viral reservoirs in macrophages that are sufficient for induction of neurocognitive impairment

Suppression of HIV replication by antiretroviral therapy (ART) or host immunity can prevent AIDS but not other HIV-associated conditions including neurocognitive impairment (HIV-NCI). Pathogenesis in HIV-suppressed individuals has been attributed to reservoirs of latent-inducible virus in resting CD4+ T cells. Macrophages are persistently infected with HIV but their role as HIV reservoirs in vivo has not been fully explored. Here we show that infection of conventional mice with chimeric HIV, EcoHIV, reproduces physiological conditions for development of disease in people on ART including immunocompetence, stable suppression of HIV replication, persistence of integrated, replication-competent HIV in T cells and macrophages, and manifestation of learning and memory deficits in behavioral tests, termed here murine HIV-NCI. EcoHIV established latent reservoirs in CD4+ T lymphocytes in chronically-infected mice but could be induced by epigenetic modulators ex vivo and in mice. In contrast, macrophages expressed EcoHIV constitutively in mice for up to 16 months; murine leukemia virus (MLV), the donor of gp80 envelope in EcoHIV, did not infect macrophages. Both EcoHIV and MLV were found in brain tissue of infected mice but only EcoHIV induced NCI. Murine HIV-NCI was prevented by antiretroviral prophylaxis but once established neither persistent EcoHIV infection in mice nor NCI could be reversed by long-acting antiretroviral therapy. EcoHIV-infected, athymic mice were more permissive to virus replication in macrophages than were wild-type mice, suffered cognitive dysfunction, as well as increased numbers of monocytes and macrophages infiltrating the brain. Our results suggest an important role of HIV expressing macrophages in HIV neuropathogenesis in hosts with suppressed HIV replication.

Early Life Stress-Related Elevations in Reaction Time Variability Are Associated with Brain Volume Reductions in HIV+ Adults

There is burgeoning evidence that, among HIV+ adults, exposure to high levels of early life stress (ELS) is associated with increased cognitive impairment as well as brain volume abnormalities and elevated neuropsychiatric symptoms. Currently, we have a limited understanding of the degree to which cognitive difficulties observed in HIV+ High-ELS samples reflect underlying neural abnormalities rather than increases in neuropsychiatric symptoms. Here, we utilized a behavioral marker of cognitive function, reaction time intra-individual variability (RT-IIV), which is sensitive to both brain volume reductions and neuropsychiatric symptoms, to elucidate the unique contributions of brain volume abnormalities and neuropsychiatric symptoms to cognitive difficulties in HIV+ High-ELS adults. We assessed the relation of RT-IIV to neuropsychiatric symptom levels and total gray and white matter volumes in 44 HIV+ adults (26 with high ELS). RT-IIV was examined during a working memory task. Self-report measures assessed current neuropsychiatric symptoms (depression, stress, post-traumatic stress disorder). Magnetic resonance imaging was used to quantify total gray and white matter volumes. Compared to Low-ELS participants, High-ELS participants exhibited elevated RT-IIV, elevated neuropsychiatric symptoms, and reduced gray and white matter volumes. Across the entire sample, RT-IIV was significantly associated with gray and white matter volumes, whereas significant associations with neuropsychiatric symptoms were not observed. In the High-ELS group, despite the presence of elevated neuropsychiatric symptom levels, brain volume reductions explained more than 13% of the variance in RT-IIV, whereas neuropsychiatric symptoms explained less than 1%. Collectively, these data provide evidence that, in HIV+ High-ELS adults, ELS-related cognitive difficulties (as indexed by RT-IIV) exhibit strong associations with global brain volumes, whereas ELS-related elevations in neuropsychiatric symptoms appear to contribute minimally to these cognitive difficulties. Such findings support a growing body of evidence indicating that high ELS exposure is a significant risk factor for neurocognitive dysfunction in HIV+ adults. Further, these data highlight the need to better understand how ELS-related pathophysiological mechanisms contribute to volumetric and other neural abnormalities in HIV+ individuals.

Experiences of Discrimination Are Associated With Greater Resting Amygdala Activity and Functional Connectivity

BACKGROUND

Social discrimination, a type of psychological stressor, is associated with poorer physical and mental health outcomes, yet we have little understanding of how discrimination affects neural functions in marginalized populations. By contrast, the effects of psychological stress on neural functions are well documented, with evidence of significant effects on the amygdala-a neural region that is central to psychosocial functions. Accordingly, we conducted an examination of the relation between self-reported discrimination exposure and amygdala activity in a diverse sample of adults.

METHODS

Seventy-four adults (43% women; 72% African American; 23% Hispanic; 32% homosexual/bisexual) completed self-report ratings of discrimination exposure. Spontaneous amygdala activity and functional connectivity were assessed during resting-state functional magnetic resonance imaging.

RESULTS

Greater discrimination exposure was associated with higher levels of spontaneous amygdala activity. Increases in discrimination were also associated with stronger functional connectivity between the amygdala and several neural regions (e.g., anterior insula, putamen, caudate, anterior cingulate, medial frontal gyrus), with the most robust effects observed in the thalamus. These effects were independent of several demographic (e.g., race, ethnicity, sex) and psychological (e.g., current stress, depression, anxiety) factors.

CONCLUSIONS

Collectively, our findings provide the first evidence that social discrimination is independently associated with elevations in intrinsic amygdala activity and functional connectivity, thus revealing clear parallels between the neural substrates of discrimination and psychological stressors of other origins. Such results should spur future investigations of amygdala-based networks as potential etiological factors linking discrimination exposure to adverse physical and mental health outcomes.

Childhood maltreatment and HIV-associated neurocognitive disorders share similar pathophysiology: a potential sensitisation mechanism?

HIV-associated neurocognitive disorders (HAND) are increasingly prevalent despite the use of antiretroviral therapies. Previous research suggests that individual host factors play an important role in determining susceptibility to HAND. In this review, we propose that childhood trauma (CT) and HAND share several common aetiological mechanisms, namely hypothalamic-pituitary-adrenal axis dysregulation, neuroinflammation and oxidative stress. These convergent and consequent mechanisms may translate into an increased risk of developing HAND in individuals who have experienced early life stress. We provide an overview of basic and clinical research relating to these pathophysiological mechanisms and suggest that further research examine brain-derived neurotrophic factor and telomere length as common mediating factors and potential therapeutic targets for HAND and CT. Graphical abstract Both childhood trauma and HIV-associated neurocognitive disorders are associated with HPA axis dysregulation, inflammation and oxidative stress.