Reactivity to social stress in ethnic minority men

A systematic review and meta-analysis of the association between emotional stress reactivity and psychosis

AIM

Emotional stress reactivity may be a mediating factor in the association between trauma and psychosis. This review aimed to (i) identify, summarise and critically evaluate the link between emotional stress reactivity and psychotic experiences (ii) examine evidence for a 'dose-response' relationship between stress reactivity and psychosis in the wider psychosis phenotype (i.e., sub-clinical symptoms).

METHODS

Electronic database searches (PsychINFO, MEDLINE, EMBASE) were conducted for studies which investigated the link between stress reactivity and psychosis, psychotic symptoms, or a vulnerability to developing psychosis (wider phenotype). Cross-sectional, experimental and experience sampling method study designs were eligible for inclusion.

RESULTS

Fourty five eligible articles were identified (N participants = 8830). Narrative synthesis showed that increased emotional stress reactivity was associated with psychosis and subclinical psychotic experiences across all study designs, however, findings were inconsistent across studies. The preliminary meta-analysis (k = 4, n = 383) showed increases in emotional stress reactivity was associated with higher negative affect in response to event-related stress, in those with psychosis compared to controls (mean difference in beta coefficients = 0.05, 95% CI 0.02-0.08, p = .004). However, this difference was small with a considerable degree of heterogeneity (p = .001, I²  = 81%) so results should be interpreted with caution.

CONCLUSIONS

Overall, the evidence suggests that there is a link between emotional stress reactivity and psychosis in those with psychosis, those at high risk of developing psychosis and in relation to subclinical psychotic-like experiences in the general population.

Emotional changes following discrimination induction in gender- and sexuality-diverse adolescents

Sexual and gender minority (SGM)-identifying adolescents are particularly vulnerable to negative psychological outcomes, including engagement in nonsuicidal self-injury (NSSI). However, little is known about why these relationships exist. We used experimental methods to test the psychological mediation framework in an online sample of 328 adolescents who reported female sex at birth and a range of sexual and gender identities. Participants reported on depressive symptoms, self-criticism (both self-report and implicit), NSSI, and discrimination. They also completed a discrimination-based mood induction to test emotional reactivity. At baseline, SGM participants reported higher levels of implicit and self-reported self-criticism, depressive symptoms, discrimination, and higher rates of NSSI compared with cisgender, heterosexual participants (ps < .03). Following the discrimination induction, SGM-identifying participants exhibited larger emotional reactivity compared with cisgender heterosexual participants, as measured by change in negative mood, F(1, 326) = 7.33, p = .01, ηp2 = .02, and state self-criticism, F(1, 326) = 4.67, p = .03, ηp2 = .014, but not implicit affect toward the self. This effect was associated with baseline depressive symptoms, self-criticism, NSSI history, and discrimination. Post hoc analyses revealed that participants who tended to reframe experiences of discrimination as opportunities for growth exhibited attenuated emotional reactivity to the induction; findings remained significant after adjusting for SGM status and event severity (ps < .001). Results indicate that adolescents identifying as SGM may experience elevated psychological distress compared with their cisgender heterosexual peers and that stigma-related stressors may increase emotion dysregulation and maladaptive cognitive styles, paralleling previously proposed psychological mediation models. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Migration, ethnicity and psychoses: evidence, models and future directions

There is a large body of research reporting high rates of psychotic disorders among many migrant and minority ethnic groups, particularly in Northern Europe. In the context of increasing migration and consequent cultural diversity in many places worldwide, these findings are a major social and public health concern. In this paper, we take stock of the current state of the art, reviewing evidence on variations in rates of psychoses and putative explanations, including relevant theories and models. We discuss in particular: a) the wide variation in reported rates of psychotic disorders by ethnic group, and b) the evidence implicating social risks to explain this variation, at ecological and individual levels. We go on to set out our proposed socio-developmental model, that posits greater exposure to systemic social risks over the life course, particularly those involving threat, hostility and violence, to explain high rates of psychoses in some migrant and minority ethnic groups. Based on this analysis, the challenge of addressing this social and public health issue needs to be met at multiple levels, including social policy, community initiatives, and mental health service reform.

Effects of oxytocin on stress reactivity and craving in veterans with co-occurring PTSD and alcohol use disorder

Posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) are highly prevalent and commonly co-occur. The dual diagnosis of PTSD/AUD is associated with serious negative sequalae, and there are currently no effective pharmacological treatments for this comorbidity. Both PTSD and AUD are characterized by dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, which helps modulate stress reactivity. Oxytocin, a neuropeptide that attenuates HPA axis dysregulation, may be beneficial for individuals with co-occurring PTSD/AUD. Thus, the current study examined the effects of intranasal oxytocin (40 IU) as compared with placebo on stress reactivity (e.g., cortisol) as well as subjective alcohol craving in response to a laboratory stress task (Trier Social Stress Task). Participants were 67 male U.S. military veterans with current PTSD and AUD (oxytocin n = 32, placebo n = 35; overall mean age = 49.06 years). Baseline cortisol levels were examined as a moderator of outcome. The findings revealed that oxytocin marginally attenuated cortisol reactivity in response to the stress task. Furthermore, oxytocin's effect was moderated by baseline cortisol level, such that oxytocin mitigated cortisol reactivity to a greater extent among participants with higher, as compared with lower, baseline cortisol. Oxytocin did not reduce craving. Although preliminary, the findings are the first to examine oxytocin in co-occurring PTSD/AUD. The findings from this study contribute to the growing literature examining the potential utility of oxytocin among individuals with psychiatric disorders, such as PTSD and substance use disorders. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Daily-life stress differentially impacts ventral striatal dopaminergic modulation of reward processing in first-degree relatives of individuals with psychosis

Emerging evidence shows that stress can impair the ability to learn from and pursue rewards, which in turn has been linked to motivational impairments characteristic of the psychotic disorder. Ventral striatal dopaminergic neurotransmission has been found to modulate reward processing, and appears to be disrupted by exposure to stress. We investigated the hypothesis that stress experienced in the everyday life has a blunting effect on reward-induced dopamine release in the ventral striatum of 16 individuals at a familial risk for psychosis compared to 16 matched control subjects. Six days of ecological momentary assessments quantified the amount of daily-life stress prior to [¹⁸F]fallypride PET imaging while performing a probabilistic reinforcement learning task. Relative to the controls, individuals at a familial risk for psychosis who encountered more daily-life stress showed significantly diminished extent of reward-induced dopamine release in the right ventral striatum, as well as poorer performance on the reward task. These findings provide the first neuromolecular evidence for stress-related deregulation of reward processing in familial predisposition to psychosis. The implication of daily-life stress in compromised modulation of reward function may facilitate the design of targeted neuropharmacological and ecological interventions.

Amygdala reactivity in ethnic minorities and its relationship to the social environment: an fMRI study

BACKGROUND

Ethnic minority individuals have an increased risk of developing a psychotic disorder, particularly if they live in areas of ethnic segregation, or low own group ethnic density. The neurobiological mechanisms underlying this ethnic minority associated risk are unknown. We used functional MRI to investigate neural responses to faces of different ethnicity, in individuals of black ethnicity, and a control group of white British ethnicity individuals.

METHODS

In total 20 individuals of black ethnicity, and 22 individuals of white British ethnicity underwent a 3T MRI scan while viewing faces of black and white ethnicity. Own group ethnic density was calculated from the 2011 census. Neighbourhood segregation was quantified using the Index of Dissimilarity method.

RESULTS

At the within-group level, both groups showed greater right amygdala activation to outgroup faces. Between groups, the black ethnicity group showed greater right amygdala activation to white faces, compared to the white ethnicity group. Within the black ethnicity group, individuals living in areas of lower own group ethnic density showed greater right amygdala reactivity to white faces (r = -0.61, p = 0.01).

CONCLUSIONS

This is the first time an increased amygdala response to white faces has been demonstrated in individuals of black ethnicity. In the black ethnicity group, correlations were observed between amygdala response and neighbourhood variables associated with increased psychosis risk. These results may have relevance for our understanding of the increased rates of paranoia and psychotic disorders in ethnic minority individuals.

Migrant and ethnic minority status as risk indicators for schizophrenia: new findings

PURPOSE OF REVIEW

Arguably, the strongest evidence of an environmental contribution to the cause of psychosis is the increased risk for certain groups of migrants and ethnic minorities. This article summarizes findings published since 2016.

RECENT FINDINGS

Two studies suggested that migration or minority status are proxies for exposure to an inferior social status. A study from Bologna, Italy, showed that the psychosis risk for internal migrants from Southern Italy was as much increased as that for international migrants. A report from New Zealand reported a higher risk for Maoris than for the remainder of the population.Furthermore, a Danish investigation showed that own-group ethnic density of the neighbourhood at age 15 strongly modified the psychosis risk at adult age. This rules out differential mobility during the prodromal phase as an explanation for the ethnic density effect. Preliminary evidence suggests that the psychotogenic effect of migration may be mediated by elevated dopamine in the striatum.

SUMMARY

An increasing body of evidence suggests that the higher psychosis risk for certain migrant or ethnic minority groups is due to an inferior social status. Neuroimaging of the dopamine system appears to be a promising avenue for research into pathogenesis.

Cortisol Awakening Response and Acute Stress Reactivity in First Nations People

First Nations people globally have a higher incidence of mental disorders and non-communicable diseases. These health inequalities are partially attributed to a complex network of social and environmental factors which likely converge on chronic psychosocial stress. We hypothesized that alterations in stress processing and the regulation of the hypothalamic-pituitary-adrenal axis might underlie health disparities in First Nations people. We assessed the cortisol awakening response and the dynamic response to a laboratory induced psychosocial stress of young Indigenous tertiary students (n = 11, mean age 23.82 years) and non-Indigenous students (n = 11) matched for age and gender. Indigenous participants had a blunted cortisol awakening response (27.40 (SD 35.00) vs. 95.24 (SD 55.23), p = 0.002), which was differentially associated with chronic experience of stress in Indigenous (r = -0.641, p = 0.046) and non-Indigenous (r = 0.652, p = 0.03) participants. The cortisol response to the laboratory induced psychosocial stress did not differ between groups. Self-reported racial discrimination was strongly associated with flattened cortisol response to stress (r = -0676, p = 0.022) and with heart rate variability (r = 0.654, p = 0.040). Our findings provide insight into potential biological factors underlying health discrepancies in ethnic minority groups.