Protective and damaging effects of stress mediators: central role of the brain

Burnout, Depression, and Stress in Emergency Department Nurses and Physicians and the Impact on Private and Work Life: A Systematic Review

Objectives

In today's fast-paced world, work-related stress is a prevalent problem, particularly among health care professionals in high-pressure environments such as emergency departments (EDs). This stress can lead to mental health disorders, such as depression and burnout, affecting job performance, patient care, and the quality of professional and private life. This systematic review aimed to investigate the prevalence of burnout, depression, and stress among ED nurses and physicians and the impact of these conditions on personal and professional quality of life (QoL).

Methods

The systematic literature search covered PubMed, PsycINFO, Embase, and grey literature databases. Articles were included if they were published in English or German by 31 January 2020, focused on ED physicians or nurses, and examined burnout, depression, or stress and its impact on professional or personal QoL. Quality assessment of the included studies was performed using a modified version of the Newcastle-Ottawa Scale.

Results

The systematic search resulted in 893 articles, of which 11 met the inclusion criteria. All reviewed studies had a cross-sectional study design and were of low to moderate quality. Depression, burnout, and stress were prevalent among ED physicians, ranging from 15.5% to 19.3%, 18% to 71.4%, and 19.5% to 22.7%, respectively. These were associated with lower job satisfaction in ED physicians, while findings in ED nurses also showed a considerable rate of burnout with an inverse association with compassion satisfaction. Burnout and stress were significantly associated with intentions to quit emergency medicine in ED physicians, whereas no association was found for depression. In addition, burnout showed a negative relationship to work-life balance and QoL, while higher stress levels were associated with lower life satisfaction in ED physicians.

Conclusion

Our review underlines the high prevalence of stress, depression, and burnout among ED health care professionals and their potential negative impact on private and professional life, emphasizing the need for targeted support and interventions to enhance resilience, reduce stress, and prevent the onset or deterioration of mental health diseases. This, in turn, can contribute to maintaining and strengthening the already limited human resources in EDs, ensuring the quality of patient care, and strengthening health care systems.

Combined Restraint Stress and Metal Exposure Paradigms in Rats: Unravelling Behavioural and Neurochemical Perturbations

Accumulation of heavy metals (Mn and Ni) and prolonged exposure to stress are associated with adverse health outcomes. Various studies have shown the impacts of stress and metal exposures on brain function. However, no study has examined the effects of co-exposure to stress, Mn, and Ni on the brain. This study addresses this gap by evaluating oxidative and glial responses, apoptotic activity, as well as cognitive processes in a rat model. Adult Wistar rats were exposed to vehicle (control), restraint stress, 25 mg/kg of manganese (Mn) or nickel (Ni), or combined restraint stress plus Mn or Ni. Following treatment, rats were subjected to several behavioural paradigms to assess cognitive function. Enzyme activity, as well as ATPase levels, were evaluated. Thereafter, an immunohistochemical procedure was utilised to evaluate neurochemical markers of glial function, myelination, oxidative stress, and apoptosis in the hippocampus, prefrontal cortex (PFC), and striatum. Results showed that stress and metal exposure increased oxidative stress markers and reduced antioxidant levels. Further, combined stress and metal exposure reduced various forms of learning and memory ability in rats. In addition, there were alterations in Iba1 activity and Nrf2 levels, reduced Olig2 and myelin basic protein (MBP) levels, and increased caspase-3 expression. These neurotoxic outcomes were mostly exacerbated by co-exposure to stress and metals. Overall, our findings establish that stress and metal exposures impaired cognitive performance, induced oxidative stress and apoptosis, and led to demyelination effects which were worsened by combined stress and metal exposure.

Pinpointing the timing of prenatal stress associated with infant biobehavioral reactivity

Prenatal stress has a well-established link to negative biobehavioral outcomes in young children, particularly for girls, but the specific timing during gestation of these associations remains unknown. In the current study, we examined differential effects of timing of prenatal stress on two infant biobehavioral outcomes [i.e., hypothalamic-pituitary-adrenal (HPA) axis reactivity and difficult temperament] that are early-life precursors to the development of psychopathology. We obtained the most granular assessment of prenatal stress to date involving weekly stress ratings from 396 pregnant women between 15 and 41 weeks gestation. At 6 months postpartum, infant salivary cortisol was collected (n = 173) before and after a stressful laboratory task and mothers reported on infant temperament (n = 244). Machine learning explored both between- and within-person regression effects of prenatal stress on the two infant biobehavioral outcomes. For HPA axis reactivity, we found a sensitive period during mid-gestation (weeks 20 and 29) for girls, but during late gestation (week 37) for boys. For difficult temperament, we found a between-persons effect of mean stress level as well as sensitive periods in mid (weeks 20, 21, 25) and late gestation (week 37) for girls, but across mid to late gestation (weeks 25, 27, 30, 34, 40) for boys. This study is the first to use a weekly assessment across gestation to demonstrate specific windows of sensitivity for infant biobehavioral precursors of child psychopathology. The findings highlight that biological sex critically influences specific timing of these prenatal stress associations with infant outcomes, thus informing our understanding of sex differences in early biobehavioral markers of psychopathology.

Serum BDNF Increase After 9-Month Contemplative Mental Training Is Associated With Decreased Cortisol Secretion and Increased Dentate Gyrus Volume: Evidence From a Randomized Clinical Trial

Background

In this study, we investigated whether mindfulness- and meditation-based mental training that improves stress regulation can upregulate BDNF (brain-derived neurotrophic factor), an important promoter of hippocampal neuroplasticity, and examined cortisol reduction as a mediating pathway.

Methods

In a randomized clinical trial, 332 healthy adults were randomly assigned to one of the 3 training cohorts or a passive control cohort. Training participants completed up to three 3-month-long modules targeting attention-based mindfulness, socio-affective skills, or socio-cognitive skills. We examined change in serum BDNF levels after each 3-month training interval; evaluated whether training effects were linked to reduced cortisol release in the long-term, diurnally, and when acutely stress-induced; and explored associations with hippocampal volume changes.

Results

In the combined training cohorts, BDNF increased significantly and cumulatively after 3-, 6-, and 9-month training relative to the pretraining baseline (3 month: t 516 = 3.57 [estimated increase: 1353 pg/mL], 6 month: t 516 = 3.45 [1557 pg/mL], 9 month: t 516 = 3.45 [2276 pg/mL]; all ps < .001). After 9 months, training cohort BDNF was not higher than control cohort BDNF, which displayed unexplained variance. However, moderated mediation analysis showed that only training effects, and not control cohort BDNF change, were partially mediated by simultaneously reduced long-term cortisol release (3-month averages) measured in hair (15.1% mediation, p = .021). Individually greater BDNF increase after training correlated with more reduced long-term and stress-induced cortisol release. Moreover, greater BDNF increase after 9 months of training correlated with dentate gyrus volume increase (t 108 = 2.09, p = .039).

Conclusions

Longitudinal contemplative training may promote a neurobiological pathway from stress reduction to increased BDNF levels to enhanced hippocampal volume. However, single serum BDNF measurements can be unreliable for assessing long-term neurotrophic effects in healthy adults. Future studies should investigate nonspecific BDNF measurement effects before considering application in preventive health care.

Lower levels of positive affect and insomnia are associated with elevated allostatic load among Ukrainian refugees

To date, several biological alterations associated with the refugee status have been investigated. However, none of them has focused on the allostatic load (AL) index that is a collective measure of biological responses to stress. Therefore, the present study aimed to assess the AL index and its correlates in 60 Ukrainian refugees who migrated to Poland after the Russian invasion. The AL index was measured in 60 Ukrainian refugees and 50 controls matched for age and sex. It was based on sex-specific distributions of 15 biomarkers (cardiovascular markers, anthropometric measures, inflammatory markers, glucose homeostasis parameters, lipids, and steroids). Psychopathological symptoms and behavioral characteristics were assessed using self-reports. Refugees had significantly higher AL index together with higher scores of insomnia, negative affect, depressive and anxiety symptoms, avoidance and hyperarousal symptoms of post-traumatic stress disorder as well as lower levels of positive affect. Similarly, a lifetime exposure to traumatic stressors was significantly higher among Ukrainian refugees. Linear regression analyses demonstrated that lower levels of positive affect (interactive effects with the refugee status but not main associations) and higher levels of insomnia (interactive effects with the refugee status and main associations) were associated with elevated AL index after adjustment for age, education, cigarette smoking status, somatic disease, medication use, and head trauma history. In summary, the findings indicate systemic dysregulations of biological stress responses in Ukrainian refugees that are attributable to higher levels of insomnia and lower levels of positive affect in this population.

The long-term effects of housing insecurity in young adulthood on subsequent material hardship, physiological and mental health

Economic and material hardship, including housing insecurity - limited or uncertain availability or access to safe, quality, and affordable housing - is strongly linked to negative physical and mental health outcomes among adolescents and adults. However, data limitations and the inherent selectivity of housing insecurity have hindered comprehensive analysis of its long-term effects on physiological and mental health. This study uses data from The National Longitudinal Study of Adolescent to Adult Health (Add Health) to construct a sample of participants who experienced housing insecurity between the ages of 18-26 (Wave III) to a suitable control group using propensity score matching. We assess the effects of housing insecurity on (1) material hardship at Wave IV (ages 24-32), (2) allostatic load (AL) and depression symptoms at Waves IV and V (ages 33-43), and (3) the change in allostatic load and depression symptoms from Wave IV to V. Further, we evaluate whether effects differ by sex. Experiencing housing insecurity is associated with a significantly higher likelihood of experiencing material hardship at Wave IV and significantly worse depressive symptoms at both Waves IV and V. The treatment effects are more pronounced among women, with housing insecurity being linked to a significant increase in allostatic load from Wave IV to Wave V exclusively for women. Our results provide crucial support that housing insecurity is not just an outcome of economic hardship but a cause of it in the future, with downstream effects on health and well-being, particularly for women.

The Utility of Prolonged Chronic Unpredictable Stress to Study the Effects of Chronic Fluoxetine, Eicosapentaenoic Acid, and Lipopolysaccharide on Anxiety-Like Behavior and Hippocampal Transcriptomic Responses in Male Rats

Chronic stress is a common trigger of multiple neuropsychiatric illnesses. Animal models are widely used to study stress-induced brain disorders and their interplay with neuroinflammation and other neuroimmune processes. Here, we apply the prolonged 12-week chronic unpredictable stress (PCUS) model to examine rat behavioral and hippocampal transcriptomic responses to stress and to chronic 4-week treatment with a classical antidepressant fluoxetine, an anti-inflammatory agent eicosapentaenoic acid (EPA), a pro-inflammatory agent lipopolysaccharide and their combinations. Overall, PCUS evoked anxiety-like behavioral phenotype in rats, corrected by chronic fluoxetine (alone or combined with other drugs), and EPA. PCUS also evoked pronounced transcriptomic responses in rat hippocampi, involving > 200 differentially expressed genes. While pharmacological manipulations did not affect hippocampal gene expression markedly, Gpr6, Drd2 and Adora2a were downregulated in stressed rats treated with fluoxetine, EPA and fluoxetine + EPA, suggesting their respective protein products (G protein-coupled receptor 6, dopamine D2 receptor and adenosine A2A receptor) as potential evolutionarily conserved targets under chronic stress. Overall, these findings support the validity of rat PCUS paradigm as a useful model to study stress-related anxiety pathogenesis, and call for further research probing how various conventional and novel drugs may (co)modulate behavioral and neurotranscriptomic biomarkers of chronic stress.

Deficiency of the palmitoyl acyltransferase ZDHHC7 modulates depression-like behaviour in female mice after a mild chronic stress paradigm

Chronic stress (CS) is a debilitating condition that negatively affects body and brain. In mice, CS effects range from changes in behaviour and brain microstructure down to the level of gene expression. These effects are partly mediated by sex and sex steroid hormones, which in turn are affected by the palmitoyl acyltransferase ZDHHC7. ZDHHC7 might modulate also the response to CS via palmitoylation of sex steroid hormone receptors and other proteins critical for neuronal structure and functions. Therefore, we aimed to investigate the role of ZDHHC7 in response to CS on different system levels in a mouse model of Zdhhc7-deficiency. Female and male Zdhhc7-knockout (KO) and -wildtype (WT) mice underwent a four-week-mild CS paradigm or non-stress control (C) condition. After C or CS, behaviours, hippocampal microstructures (via MRI-based diffusion tensor imaging) and brain gene expression profiles (via mRNA-seq transcriptomics) were investigated. Analyses focused on effects of genotype (KO vs. WT) or condition (C vs. CS) separately in both sexes. Our results revealed significant effects particularly in females. Female KOs displayed increased locomotion and reduced depression-like behaviour after CS (KO vs. WT, C vs. CS: pall < 0.05). Hippocampal fibres were reduced in female KOs after C (KO vs. WT: pall < 0.05) but in female WTs after CS (C vs. CS: pall < 0.05). Furthermore, female KOs showed increased cortistatin expression after CS (C vs. CS: mRNAseq and qPCR pall < 0.05). In sum, Zdhhc7-deficiency reduced depression-like behaviours, prevented hippocampal fibre reduction and upregulated cortistatin after CS. It seemed to be related to a sex-specific stress response and may reveal genetic factors of CS-resilience in female mice.

The potential of dynamic plants for attention and stress recovery in indoor environment

This study simulates the natural movement of plants in indoor environments to investigate whether these plants can effectively facilitate psychological, physiological, and emotional recovery from fatigue caused by short vigilance tasks. A total of 63 participants completed baseline assessments of emotional and physiological stress as well as attention and memory (including the POMS-SF, blood pressure, pulse, and Digit Span Backward). They then performed a vigilance task to induce fatigue, followed by a second measurement of stress and cognition. After random assignment to dynamic plant, static plant, or no-plant conditions for a rest intervention, participants underwent a final assessment. The results showed that all three conditions experienced significant fatigue induced by the vigilance task, with increases in stress and reductions in cognition. Following the intervention, those in the dynamic plant condition exhibited notably greater recovery across multiple indices-particularly in emotional stress and pulse-than those in the other conditions.

COVID-19 Vaccine Hesitancy Among Black Women in the US

Importance

COVID-19 vaccine hesitancy among Black women is a critical public health concern, potentially exacerbating existing health disparities and impacting community-wide vaccination efforts.

Objective

To explore the factors associated with COVID-19 vaccine hesitancy among Black women in the US and identify the specific concerns and experiences shaping hesitant attitudes toward vaccination.

Design, Setting, and Participants

Qualitative study using in-depth, semistructured interviews conducted virtually between June and November 2021. Thematic analysis was used to identify key themes from the interview data. Participants were recruited through social media platforms and word-of-mouth referrals from various regions of the US. Interviews were conducted remotely via Zoom. Data were analyzed from June to October 2023.

Main Outcomes and Measures

Identification of key themes associated with COVID-19 vaccine hesitancy, identified through thematic analysis of interview data.

Results

Fifty-four Black women aged 21 to 66 years participated in the study. Most participants (41 [75.9%]) resided in the South. The sample was predominantly well-educated, with 41 (75.9%) holding a bachelor's degree or higher. Income levels varied, with 16 (29.6%) earning between $40 000 and $59 999 annually. Regarding family structure, 32 participants (59.3%) reported having no children, while 22 (40.7%) had 1 or more children. Three primary themes emerged as being associated with vaccine hesitancy: (1) mistrust in health care and government, rooted in past medical exploitation; (2) concerns over vaccine safety and long-term effects, particularly regarding reproductive health; and (3) ineffective and coercive vaccine communication and promotion. Participants expressed deep-rooted skepticism about being treated as "expendable" in medical research, fears about the rapid vaccine development process, and frustration with coercive vaccine advertisements. Many women desired more comprehensive education about vaccine mechanisms and criticized the use of coercive financial incentives and celebrity endorsements in vaccine promotion.

Conclusions and Relevance

Addressing COVID-19 vaccine hesitancy among Black women requires a multifaceted approach that acknowledges historical traumas, provides clear and transparent safety information, and avoids coercive vaccine promotion strategies. These findings emphasize the need for health care practitioners and public health officials to prioritize trust-building, engage community leaders, and tailor interventions to address the unique concerns of Black women to improve vaccine confidence and uptake.

Accelerometer-based heart rate adjustment for ambulatory stress research

Using heart rate (HR) measurements to detect mental stress in naturalistic settings is hampered by the physiological impact of hemodynamic and metabolic demands. Correcting HR for these demands can help isolate fluctuations in HR associated with psychosocial stress responses, a concept termed additional heart rate (aHR). This study examined whether adding predictors for posture, activity type, and lagged movement intensity for the prolonged impact of physical activity (PA) improved aHR estimation across various manipulations of mental stress, posture, and PA in a controlled laboratory environment (n = 197). Accelerometer signals were used to obtain the movement intensity and to classify posture and activity type. Posture, activity type, and lagged movement intensity each led to a significant improvement in HR estimation, as measured by adjusted R2 and root mean squared error. However, HR was overestimated during quiet sitting. The aHR, computed as the difference between observed and predicted HR, generally underestimated observed task-baseline reactivity but was sensitive to individual differences in reactivity to mental stressors. Between-subject correlations of aHR with task-baseline reactivity ranged from 0.62 to 0.93 across conditions. On a within-subject level, the ability of aHR to differentiate between exposure to physical stress and mental stress was limited (recall = 0.32, precision = 0.31), but better than that of observed HR (recall = 0.02, precision = 0.02). Future research should explore the potential of this novel aHR estimation method in differentiating physical and mental demands on HR in daily life, and its predictive value for health outcomes.

Effects of Allostatic Load on Long-Term Survival After Stroke

BACKGROUND

Allostatic load index (ALI) is often utilized to quantify the physiological response to stress. This study assesses the relationship between ALI and its impact on all-cause, cardiovascular, and stroke mortality in individuals with a self-reported history of stroke and within the general National Health and Nutritional Examination Survey sampled population.

METHODS

Using data from the National Health and Nutritional Examination Survey (III, 1988-1994) and the 2015 Linked Mortality File, we selected adults aged ≥25 years with self-reported stroke. We computed the weighted prevalence of each ALI category to obtain nationally representative estimates with higher ALI corresponding to a higher stress burden. We evaluated the relationship between ALI category and mortality outcomes using the Cox proportional hazard model, considering the survey design variables and adjusting for age, sex, race/ethnicity, education, marital status, income, drinking, and smoking status.

RESULTS

Of 17 284 people screened in the National Health and Nutritional Examination Survey sample population, 15 567 individuals were included in the study. The ALI distribution was 48.3% ALI ≤1, 21.7% ALI=2, and 30% ALI ≥3. Of 414 individuals with a reported history of stroke, there were 11.8% ALI ≤1, 22.1% ALI=2, and 66.1% ALI ≥3. There was an association between a higher ALI and older age, Black and Mexican American race, and >1 comorbidity in the overall sampled population. In the population with prior stroke, those with ALI ≥3 had 2.7× higher adjusted all-cause mortality (hazard ratio, 2.7 [CI, 1.5-4.9]) and 4.5× higher adjusted cardiovascular mortality (hazard ratio, 4.5 [CI, 1.4-14.3]) compared with those with ALI ≤1. In the general sampled National Health and Nutritional Examination Survey population, the ALI ≥3 group had 1.8× higher adjusted stroke mortality (hazard ratio, 1.8 [CI, 1.1-3.1]).

CONCLUSIONS

Baseline higher ALI is associated with greater all-cause and cardiovascular mortality in stroke survivors and greater stroke mortality in the overall sampled National Health and Nutritional Examination Survey population.

Changes in hippocampal volume and affective functioning after a moderate intensity running intervention

This study examined the effects of a moderately intense seven-week running intervention on the hippocampal volume and depressive symptoms of young men (20-31 years of age) from the general population (N = 21). A within-subjects-design involving a two-week baseline period before the running intervention, and two subsequent intervention cycles was applied. At four time points of assessment (t1: start of the study; t2: end of baseline period/start of the intervention; t3: end of the first intervention cycle; t4: end of the 2nd intervention cycle/study end) magnetic resonance imaging was performed and symptoms related to depression were assessed employing the Center for Epidemiological Studies Depression (CES-D) Scale. The intervention resulted in a significant increase in the estimated maximum oxygen uptake (VO2max), measured with a standardized walking test (average increase from 42.07 ml*kg- 1*min- 1 to 46.07 ml*kg- 1*min- 1). The CES-D scores decreased significantly over the course of the running intervention (average decrease from 12.76 to 10.48 on a 20-point scale). Significant volumetric increases in the hippocampus were found, most notably after the first intervention cycle in the left (average increase from 613.41 mm³ to 620.55 mm³) and right hippocampal tail (average increase from 629.77 mm³ to 638.17 mm³). These findings provide new evidence regarding the temporal dynamics of hippocampal changes following engagement in physical activity.

Loneliness Gets Under the Skin: A Scoping Review Exploring the Link Between Loneliness and Biological Measures of Inflammation

BACKGROUND

Research suggests that systemic inflammation may link loneliness to adverse health outcomes, yet there is a gap in comprehensively reviewing recent evidence on the relationship between loneliness and biological measures of inflammation in adults. This scoping review synthesizes current research to address the question: Is there a definitive link between loneliness and biological markers of inflammation in adults?

METHODS

Following the methods outlined by Arksey and O'Malley, we developed a protocol, defined our research question, and systematically searched PubMed, CINAHL, Embase, and Scopus for English-language studies conducted from 2018 to 2023 exploring the relationship between loneliness and biomarkers of inflammation in adults.

RESULTS

Twelve studies meeting the inclusion criteria displayed heterogeneity in terms of sample characteristics, loneliness scales, and inflammatory biomarkers. The UCLA Loneliness Scale, in various forms, emerged as the predominant tool for measuring loneliness, while C-reactive protein and interleukin-6 were the most frequently evaluated inflammatory biomarkers. Notably, all 12 studies reported an association between loneliness and at least 1 biological marker of inflammation.

CONCLUSION

Research consistently associates loneliness with poor health outcomes in aging adults, but the underlying mechanisms remain unclear. This scoping review suggests that inflammation may serve as a pathway linking loneliness to adverse health outcomes. However, the variability across studies highlights the need for standardized measurement methods and a consideration of both the duration and extent of loneliness. Enhancing our understanding of how loneliness affects systemic inflammation may help clarify why loneliness is associated with negative health outcomes.

Trajectories of posttraumatic stress symptoms following collective violence: A systematic review and meta-analyses

Although collective violence represents a significant public health concern, a limited number of longitudinal studies have addressed this topic, with no systematic reviews focusing on posttraumatic stress symptom (PTSS) trajectories. The present systematic review and meta-analyses examined PTSS prevalence and trajectories after exposure to collective violence. A systematic literature search across six databases (APA PsycInfo, APA PsycArticles, PSYINDEX, MEDLINE, ERIC, and PubMed) identified 771 studies that were screened for the following eligibility criteria: exposure to collective violence, adult sample, longitudinal design, PTSS assessment using validated measures, PTSS trajectories estimated using latent growth modeling, and report sample prevalence rate for each trajectory. Ten studies met the criteria, and five meta-analyses were performed to assess the overall prevalence of each trajectory. Most included studies (63.6%) identified four trajectories, characterized as low-stable, high-stable, decreasing, and delayed-worsening. The low-stable trajectory was the modal response, with a pooled prevalence of 58.0%, 95% CI [51.0, 65.0]. The high-stable prevalence was 7.0%, 95% CI [4.0, 19.0]; the decreasing trajectory was 13%, 95% CI [9.0, 17.0]; and the delayed-worsening trajectory was 8.0%, 95% CI [5.0, 10.0]. A fifth trajectory, moderately stable, had a prevalence of 19.0%, 95% CI [9.0, 29.0]. The trajectory models robustly identified clinically relevant patterns of response to collective violence, offering a contribution to the literature and a starting point for future research. Further studies are needed, as a better comprehension of symptom trajectories after collective violence events has important clinical and public health implications.

Psychological stress dysfunction in women with premenstrual syndrome

Premenstrual syndrome (PMS) encompasses a range of emotional, physiological, and behavioral symptoms that occur during the luteal phase of the menstrual cycle (MC) and resolve with the onset of menstruation. These symptoms, which can include fatigue, physical pain, anxiety, irritability, and depression, significantly affect women's daily lives and overall well-being. In severe cases, PMS can progress to premenstrual dysphoric disorder (PMDD), profoundly impairing quality of life. Despite its prevalence, the neural mechanisms underlying PMS-particularly those related to stress-are not fully understood.This review aims to explore the complex interactions between PMS and stress, with a focus on the hormonal pathways involved. We propose that abnormal stress coping styles and stress reactivity patterns, collectively referred to as stress dysfunction, are crucial factors influencing women's vulnerability to PMS. We examine the relationship between PMS and stress from four perspectives: (1) PMS shares neuroendocrine metabolic circuits based on hormonal fluctuations with stress reactivity systems; (2) there is comorbidity between PMS and stress-related disorders; (3) PMS itself may act as a stressor, potentially creating a negative feedback loop that exacerbates symptoms; and (4) biofeedback training used for stress disorders may be effective in treating PMS. By providing a detailed analysis of stress-related hormonal changes and their effects on PMS, this review offers new insights into the physiological processes underlying PMS. Understanding these interactions may inform the development of targeted interventions and improve the quality of life for women affected by PMS.

A Narrative Review on Stress and Itch: What We Know and What We Would Like to Know

Itch is one of the most prevalent symptoms experienced by patients with inflammatory skin conditions, yet it is also one of the most debilitating. Patients suffering from chronic itch have been found to have significantly higher stress levels compared with those not experiencing itch. In fact, recent studies have revealed a bidirectional relationship between stress and itch, where each condition worsens the other. This is thought to be driven by the vicious itch-scratch cycle, which is fueled by underlying inflammation. The precise molecular pathways and mediators involved, however, remain unclear. This narrative review discusses the existing research on the relationship between stress and itch and outlines future research directions that will be necessary to advance our understanding and treatment of these conditions. Given that the effective management of both symptoms often requires a combined treatment approach, further investigation into their shared mechanisms is essential for identifying successful therapies and improving patient outcomes.

Sex Differences in the Neuroendocrine Stress Response: A View from a CRH-Reporting Mouse Line

Corticotropin-releasing hormone (CRH) neurons within the paraventricular hypothalamic nucleus (PVH) play a crucial role in initiating the neuroendocrine response to stress and are also pivotal in coordination of autonomic, metabolic, and behavioral stress reactions. Although the role of parvocellular CRHPVH neurons in activation of the hypothalamic-pituitary-adrenal (HPA) axis is well established, the distribution and function of CRH-expressing neurons across the whole central nervous system are less understood. Stress responses activate complex neural networks, which differ depending on the type of stressor and on the sex of the individual. Because of the technical difficulties of localizing CRH neurons throughout the rodent brain, several CRH reporter mouse lines have recently been developed. In this study, we used Crh-IRES-Cre;Ai9 reporter mice to examine whether CRH neurons are recruited in a stressor- or sex-specific manner, both within and outside the hypothalamus. In contrast to the clear sexual dimorphism of CRH-mRNA-expressing neurons, quantification of CRH-reporting, tdTomato-positive neurons in different stress-related brain areas revealed only subtle differences between male and female subjects. These results strongly imply that sex differences in CRH mRNA expression occur later in development under the influence of sex steroids and reflects the limitations of using genetic reporter constructs to reveal the current physiological/transcriptional status of a specific neuron population. Next, we compared the recruitment of stress-related, tdTomato-expressing (putative CRH) neurons in male and female Crh-IRES-Cre;Ai9 reporter mice that had been exposed to predator odor. In male mice, fox odor triggered more c-Fos in the CRH neurons of the paraventricular hypothalamic nucleus, central amygdala, and anterolateral bed nucleus of the stria terminalis compared to females. These results indicate that male mice are more sensitive to predator exposure due to a combination of hormonal, environmental, and behavioral factors.

Does Relative Energy Deficiency in Sport (REDs) Syndrome Exist?

Relative energy deficiency in sport (REDs) is a widely adopted model, originally proposed by an International Olympic Committee (IOC) expert panel in 2014 and recently updated in an IOC 2023 consensus statement. The model describes how low energy availability (LEA) causes a wide range of deleterious health and performance outcomes in athletes. With increasing frequency, sports practitioners are diagnosing athletes with "REDs," or "REDs syndrome," based largely upon symptom presentation. The purpose of this review is not to "debunk" REDs but to challenge dogmas and encourage rigorous scientific processes. We critically discuss the REDs concept and existing empirical evidence available to support the model. The consensus (IOC 2023) is that energy availability, which is at the core of REDs syndrome, is impossible to measure accurately enough in the field, and therefore, the only way to diagnose an athlete with REDs appears to be by studying symptom presentation and risk factors. However, the symptoms are rather generic, and the causes likely multifactorial. Here we discuss that (1) it is very difficult to isolate the effects of LEA from other potential causes of the same symptoms (in the laboratory but even more so in the field); (2) the model is grounded in the idea that one factor causes symptoms rather than a combination of factors adding up to the etiology. For example, the model does not allow for high allostatic load (psychophysiological "wear and tear") to explain the symptoms; (3) the REDs diagnosis is by definition biased because one is trying to prove that the correct diagnosis is REDs, by excluding other potential causes (referred to as differential diagnosis, although a differential diagnosis is supposed to find the cause, not demonstrate that it is a pre-determined cause); (4) observational/cross-sectional studies have typically been short duration (< 7 days) and do not address the long term "problematic LEA," as described in the IOC 2023 consensus statement; and (5) the evidence is not as convincing as it is sometimes believed to be (i.e., many practitioners believe REDs is well established). Very few studies can demonstrate causality between LEA and symptoms, most studies demonstrate associations and there is a worrying number of (narrative) reviews on the topic, relative to original research. Here we suggest that the athlete is best served by an unbiased approach that places health at the center, leaving open all possible explanations for the presented symptoms. Practitioners could use a checklist that addresses eight categories of potential causes and involve the relevant experts if and when needed. The Athlete Health and Readiness Checklist (AHaRC) we introduce here simply consists of tools that have already been developed by various expert/consensus statements to monitor and troubleshoot aspects of athlete health and performance issues. Isolating the purported effects of LEA from the myriad of other potential causes of REDs symptoms is experimentally challenging. This renders the REDs model somewhat immune to falsification and we may never definitively answer the question, "does REDs syndrome exist?" From a practical point of view, it is not necessary to isolate LEA as a cause because all potential areas of health and performance improvement should be identified and tackled.

Does the media (also) keep the score? Media-based exposure to the Russian-Ukrainian war and mental health in Portugal

The Russian-Ukrainian war (RUW) is responsible for extensive individual suffering and a socio-economic impact on the world and is reshaping global affairs. Many studies have focused on direct exposure to conflict and several public health policies have been devised. Nonetheless, indirect exposure through media has received minimal attention and there is limited evidence that mental health symptoms and disorders may arise as a result. We explored the role of voluntary or involuntary media-based exposure to the RUW on individuals' mental health including stress symptoms, coping strategies, daily functioning, and worries across demographic variables. In our sample, subjects with involuntary and higher amount of exposure seem to have higher stress symptoms. Also, those who had previous ruminations on war issues could be at risk of developing more post-traumatic stress symptoms. Therefore, media appears to be a conduit that spreads negative consequences of community trauma beyond directly affected communities.

Association between allostatic load and depression in patients with sleep disorders: Evidence from the National Health and Nutrition Examination Survey (NHANES)

OBJECTIVE

Allostatic load (AL) is an indicator of the cumulative wear and tear on the body's physiological systems that can predict onset of a range of health problems. However, the relationship between AL and depression in patients with sleep disorders is unclear. This study explored the association between AL and depression in patients with sleep disorders.

METHODS

Using data from the 2015-2016 National Health and Nutrition Examination Survey, a total of 4618 adults aged 18 years and older in the United States were included in this cross-sectional analysis. AL was calculated using nine biological markers, with a score of ≥3 indicating a high level. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9), with a score of ≥10 indicating risk for depression. Logistic regression models were employed to analyze the relationship between AL and depression.

RESULTS

Among the 1309 participants diagnosed with sleep disorders, 212 (16.2%) were identified as being at risk for depression on the PHQ-9. A total of 55.2% (n = 117) of depressed persons had high AL levels. In the unadjusted model, AL levels were associated with depression in those with sleep disorders (OR=1.53, 95% CI = 1.14-2.05, p < 0.01). This relationship remained significant in the adjusted model (OR=1.52, 95% CI=1.11-2.10, p < 0.05), after controlling for potential confounders.

CONCLUSION

High AL levels in patients with sleep disorders were positively associated with depression, indicating that elevated AL may increase the risk of depression in this population, or alternatively, depression may increase the risk of AL.

Early life stress induces decreased expression of CB1R and FAAH and epigenetic changes in the medial prefrontal cortex of male rats

Several studies in both animal models and in humans have provided substantial evidence that early life stress (ELS) induces long-term changes in behavior and brain function, making it a significant risk factor in the aetiology of various mental disorders, including anxiety and depression. In this study, we tested the hypothesis that ELS in male rats (i) leads to increased anxiety and depressive-like symptoms; and (ii) that these behavioral changes are associated with functional alterations in the endocannabinoid system of the medial prefrontal cortex (mPFC). We further assessed whether the predicted changes in the gene expression of two key components of the endocannabinoid system, cannabinoid receptor 1 (CB1R) and the fatty acid amide hydrolase (FAAH), are regulated by epigenetic mechanisms. Behavioral profiling revealed that the proportion of behaviorally affected animals was increased in ELS exposed male rats compared to control animals, specifically showing symptoms of anhedonia and impaired social behavior. On the molecular level we observed a decrease in CB1R and FAAH mRNA expression in the mPFC of adult ELS exposed animals. These gene expression changes were accompanied by reduced global histone 3 acetylation in the mPFC, while no significant changes in DNA methylation and no significant changes of histone-acetylation at the promoter regions of the analyzed genes were detected. Taken together, our data provide evidence that ELS induces a long-term reduction of CB1R and FAAH expression in the mPFC of adult male rats, which may partially contribute to the ELS-induced changes in adult socio-emotional behavior.

Tipping Point: Pathogenic Stress and the Biopolitics of Euthanasia

Hopelessness and demoralization following a terminal diagnosis can affect the capacity for self-governance. Such dispositions can increase the allostatic load-the cumulative burden of stress and anxiety-resulting in a neurophysiologic decline that can impair autonomy and influence the desire to end one's life deliberately. An allostatic overload is characterized by the inability to autoregulate stress and is associated with pathological changes to the hypothalamic-pituitary-adrenal axis and hippocampus. These changes raise concerns about the reliability of concepts of autonomy in extremis, potentially undermining arguments that are used to justify voluntary euthanasia and medically assisted death. Studies have associated depression and hopelessness with suicidal ideation in the general population. However, fewer studies have examined how patients without a history of depression or suicidal ideation may suddenly contemplate the act when facing a terminal prognosis. This paper will argue that an allostatic overload can help explain how the spectrum of physical and psychological comorbidities associated with the onset of a terminal illness can influence a decision to hasten death. Data show that patients with a terminal disease wishing to hasten death typically exhibit lower rates of clinical depression, higher rates of demoralization, and a greater likelihood of rational suicide. These differences indicate that suicidal ideation in the terminal disease patient population is different. Changes in autonomous decision-making secondary to pathological alterations in the brain may offer an explanation. Such changes have been shown to dysregulate executive control functions, specifically intentionality and voluntariness. Clinical evidence also indicates that spirituality and hopefulness can help manage the allostatic load during the palliative stages of a disease so that patients can better process end-of-life decisions. Based on these data, this paper will further argue that jurisdictions offering euthanasia are morally compelled to make mental and spiritual counseling available to patients seeking this course of action.

Adverse childhood experiences and externalizing, internalizing, and prosocial behaviors in children and adolescents: A longitudinal study

BACKGROUND

Adverse childhood experiences (ACEs) have a profound impact on individuals, shaping their long-term health and life opportunities. This study delves into the complex ties between ACEs and the socioemotional development of Australian children and youth by examining the relationships between adverse childhood experiences and externalizing, internalizing, and prosocial behaviors.

METHODS

This study utilized data from the Longitudinal Study of Australian Children and employed the generalized estimating equation method to investigate the relationships between adverse childhood experiences and externalizing, internalizing, and prosocial behaviors in Australian children and adolescents.

RESULTS

Adverse childhood experiences such as physical punishment, hostile parenting, parental conflicts, separation, financial strain, and parental mental health issues increased the risk of externalizing and internalizing behaviors while reducing prosocial behaviors. The risk increases with the number of ACEs, as evidenced by the incidence ratio (IR); for example, for externalizing behaviors, an ACEs score of one leads to IR = 1.69, while an ACEs score of 4 results in IR = 3.34. Similar trends were observed for internalizing and prosocial behaviors.

LIMITATIONS

The presence of imbalanced longitudinal data, arising from variations in the number of observations across different time points, challenges robust inferences. Furthermore, this study investigates the relationship between ACEs and behavioral problems, without establishing causality. Consequently, the results should be interpreted with caution.

CONCLUSIONS

The findings of this study highlight that adverse childhood experiences significantly influence behavioral outcomes in children and adolescents. These findings underscore the critical need for early detection and intervention to mitigate the consequences of traumatic childhood experiences.

Association of Allostatic Load With Depression, Anxiety, and Suicide: A Prospective Cohort Study

BACKGROUND

Allostatic load (AL) is an objective measure of the biological components of chronic stress in clinical practice, which potentially influence depression, anxiety, and suicide. In this study, we investigated the association between AL and these mental disorders.

METHODS

In this cohort study of 333,017 adults, participants without previous diagnoses of depression, anxiety, or suicide were observed from March 13, 2006, to October 31, 2022. AL was estimated using 10 biomarkers that reflect metabolic, cardiovascular, and inflammatory dysregulation. Diagnoses were based on ICD-10. We performed Cox proportional hazard models to assess the relationship between AL and these mental disorders. We also conducted subgroup analyses for sex, age, and Townsend Deprivation Index, as well as sensitivity analyses.

RESULTS

The median follow-up period was 13 years. Over the follow-up period, 13,441 (4.04%) participants developed depression, 13,903 (4.17%) developed anxiety, and 796 (0.24%) committed suicide. In the fully adjusted model, individuals with high AL had an increased risk of depression (hazard ratio = 1.389, p = 8.38 × 10-27), anxiety (hazard ratio = 1.304, p = 5.82 ×10-19), and suicide (hazard ratio = 1.433, p = 4.46 ×10-3). Women and younger individuals with high AL were vulnerable to depression and anxiety, while moderate AL levels were significantly associated with suicide in men and younger participants. Moreover, individuals with middle and high AL had an elevated risk of comorbid depression and anxiety.

CONCLUSIONS

High AL is positively associated with increased risks of depression, anxiety, and suicide, highlighting its potential as a predictive tool in mental health.

Persistent low job control and subsequent major depression: A prospective cohort study of Australian working males

Workers' perception of control over work is a key construct in the relationship between the psychosocial work environment and health. While exposure to low job control has been prospectively linked to poor mental health including depression and anxiety, there is less research examining the impact of prolonged exposure to low job control on mental health. Data from 5054 employed men from 2013 to 2021 in the Australian Longitudinal Study on Male Health was used to examine persistent and intermittent low job control and subsequent major depression symptoms. Persistent low job control was based on consecutive self-reports of low job control over waves 1 and 2. Combinations of low and high job control were classified as intermittent exposure and continuous high job control exposure over both waves was classified as persistent high job control. Major depression symptoms, derived from the Patient Health Questionnaire-9, was measured in wave 3. Generalised linear models and augmented inverse probability weighting were undertaken. There was a strong stepwise relationship between low job control and major depression. Compared to persistent high job control, intermittent low job control was associated with an increased risk of subsequent major depression symptoms by 32% (RR 1.32, 95% CI 0.82, 2.15); and persistent low job control by 103% (RR 2.03, 95% CI 1.21, 3.41). Compared to men exposed to persistent high job control, the average treatment effect for persistent low job control was 0.036 (95%CI 0.014, 0.058) and intermittent low job control 0.019 (95%CI 0.006, 0.032) equating to a risk ratio of 2.46 (95%CI 1.43, 3.50) and 1.79 (95% CI 1.14, 2.45) respectively. This study's findings have implications for public health and occupational policies, as they underscore the importance of reducing prolonged exposure to low job control to protect against the risk of major depression in the working population.

Allostasis as a consequence of high heat load in grain-fed feedlot cattle

Heat wave intensity, frequency, and duration are increasing in many regions of the world, including locations where highly productive livestock are raised. There are animal health and welfare, as well as economic impacts from these events. In this study, the physiological responses of grain-fed steers during a high heat load challenge through to recovery in climate-controlled rooms (CCR) were intensively evaluated. Two cohorts of 12 Black Angus steers (BW, 615.4 ± 40.1 kg) sequentially underwent a simulated heatwave event that consisted of 3 phases in the CCR: PreChallenge (5 d duration and temperature humidity index (THI) range of 65 to 71), Challenge (7-d duration and THI 66 to 95 with diurnal cycling), and Recovery (5 d duration and THI 65 to 70). The Challenge period was modeled on a severe heat wave, characterized by 3 very hot days. Individual rumen temperature (RumT, °C) was collected every 10 min, and respiration rate (RR, breaths per minute), panting score (PS), and water usage (L·steer-1·day-1) were obtained at multiple time points daily, by trained observers. Individual animal daily DMI was also determined. Morning (0700 hours) rectal temperature (RecT, °C) was measured on days 3, 5, 7 to 13, 15, and 17. Not unexpectedly, RumT, RecT, RR, and PS rose during Challenge and fell rapidly as conditions eased. Conversely, DMI was reduced during Challenge. During the transition between PreChallenge and Challenge, there were abrupt increases in RumT, and RR. It was also very apparent that during Recovery the steers did not return to the baseline PreChallenge state. Compared to PreChallenge, Recovery was characterized by persistent lowered daily mean RumT (P = 0.0010), RecT (P = 0.0922), RR (P = 0.0257), PS (P ≤ 0.0001), and DMI (P ≤ 0.0001). These results provide evidence that these steers have undergone an allostatic response in response to high heat load, and the new adjusted physiological state post-heat event may not be transient.

Neural foundation of the diathesis-stress model: longitudinal gray matter volume changes in response to stressful life events in major depressive disorder and healthy controls

Recurrences of depressive episodes in major depressive disorder (MDD) can be explained by the diathesis-stress model, suggesting that stressful life events (SLEs) can trigger MDD episodes in individuals with pre-existing vulnerabilities. However, the longitudinal neurobiological impact of SLEs on gray matter volume (GMV) in MDD and its interaction with early-life adversity remains unresolved. In 754 participants aged 18-65 years (362 MDD patients; 392 healthy controls; HCs), we assessed longitudinal associations between SLEs (Life Events Questionnaire) and whole-brain GMV changes (3 Tesla MRI) during a 2-year interval, using voxel-based morphometry in SPM12/CAT12. We also explored the potential moderating role of childhood maltreatment (Childhood Trauma Questionnaire) on these associations. Over the 2-year interval, HCs demonstrated significant GMV reductions in the middle frontal, precentral, and postcentral gyri in response to higher levels of SLEs, while MDD patients showed no such GMV changes. Childhood maltreatment did not moderate these associations in either group. However, MDD patients who had at least one depressive episode during the 2-year interval, compared to those who did not, or HCs, showed GMV increases in the middle frontal, precentral, and postcentral gyri associated with an increase in SLEs and childhood maltreatment. Our findings indicate distinct GMV changes in response to SLEs between MDD patients and HCs. GMV decreases in HCs may represent adaptive responses to stress, whereas GMV increases in MDD patients with both childhood maltreatment and a depressive episode during the 2-year interval may indicate maladaptive changes, suggesting a neural foundation for the diathesis-stress model in MDD recurrences.

Stress and cardiovascular disease: an update

Psychological stress is generally accepted to be associated with an increased risk of cardiovascular disease (CVD), but results have varied in terms of how stress is measured and the strength of the association. Additionally, the mechanisms and potential causal links have remained speculative despite decades of research. The physiological responses to stress are well characterized, but their contribution to the development and progression of CVD has received little attention in empirical studies. Evidence suggests that physiological responses to stress have a fundamental role in the risk of CVD and that haemodynamic, vascular and immune perturbations triggered by stress are especially implicated. Stress response physiology is regulated by the corticolimbic regions of the brain, which have outputs to the autonomic nervous system. Variation in these regulatory pathways might explain interindividual differences in vulnerability to stress. Dynamic perturbations in autonomic, immune and vascular functions are probably also implicated as CVD risk mechanisms of chronic, recurring and cumulative stressful exposures, but more data are needed from prospective studies and from assessments in real-life situations. Psychological assessment remains insufficiently recognized in clinical care and prevention. Although stress-reduction interventions might mitigate perceived stress levels and potentially reduce cardiovascular risk, more data from randomized trials are needed.

Racial/ethnic disparities in chronic wounds: Perspectives on linking upstream factors to health outcomes

This review explores the complex relationship between social determinants of health and the biology of chronic wounds associated with diabetes mellitus, with an emphasis on racial/ethnic disparities. Chronic wounds pose significant healthcare challenges, often leading to severe complications for millions of people in the United States, and disproportionally affect African American, Hispanic, and Native American individuals. Social determinants of health, including economic stability, access to healthcare, education, and environmental conditions, likely influence stress, weathering, and nutrition, collectively shaping vulnerability to chronic diseases, such as obesity and DM, and an elevated risk of chronic wounds and subsequent lower extremity amputations. Here, we review these issues and discuss the urgent need for further research focusing on understanding the mechanisms underlying racial/ethnic disparities in chronic wounds, particularly social deprivation, weathering, and nutrition, to inform interventions to address these disparities.

How is variability in physiological responses to social stress related to punishment and reward sensitivities? Preliminary findings from the revised reinforcement sensitivity theory of personality perspective

OBJECTIVE

Although personality traits are assumed to have biological/physiological foundations, research has yielded mixed evidence regarding the relationship between personality and physiological stress responses. Moreover, the field has often overlooked the contemporary neuroscience-based personality approach, known as the Reinforcement Sensitivity Theory (RST) of Personality, in stress research.

METHOD

The present study examined the relationship between the revised RST's personality dimensions and heart rate and skin conductance level (SCL) in response to the Trier Social Stress Test in a sample of 61 healthy university students.

RESULTS

Piecewise latent growth curve analysis controlling for the participants' current life stress, smoking use, and caffeine intake revealed that individuals with higher behavioral inhibition exhibited higher physiological reactivity, whereas those with high reward sensitivity showed smaller heart rate reactivity. The behavioral disengagement facet of the behavioral inhibition scale was associated with reduced sympathetic arousal during the stress task. Additionally, reward interest was associated with a larger recovery of SCL.

CONCLUSION

Results were generally in line with the revised theory. The study findings were discussed within the paradigm of the approach-avoidance conflict and highlighted the importance of reward sensitivity in stress resilience.

Pitavastatin attenuates hypercholesterolemia-induced decline in serotonin transporter availability

INTRODUCTION

Hypercholesterolemia is associated with increased inflammation and impaired serotonin neurotransmission, potentially contributing to depressive symptoms. However, the role of statins, particularly pitavastatin, in modulating serotonin transporter (SERT) function within this context remains underexplored. This study aimed to investigate whether pitavastatin counteracts the neurobiological effects of hypercholesterolemia.

METHODS

Low-density lipoprotein receptor knockout (LDLR-/-) mice on a C57BL/6 background were assigned to three groups: a control group fed a standard chow diet, a group fed a high-fat diet (HFD), and a third group fed a high-fat diet supplemented with pitavastatin (HFD + Pita). We evaluated the effects of HFD with or without pitavastatin on lipid profiles, inflammatory markers, and SERT availability using small-animal positron emission tomography (PET) scans with the radioligand 4-[18F]-ADAM over a 20-week period.

RESULTS

Pitavastatin treatment in HFD-fed mice significantly reduced both total cholesterol and LDL cholesterol levels in HFD-fed mice compared to those on HFD alone. Elevated inflammatory markers such as IL-1α, MCP-1/CCL2, and TNF-α in HFD mice were notably decreased in the HFD + Pita group. PET scans showed reduced SERT availability in the brains of HFD mice; however, pitavastatin improved this in brain regions associated with mood regulation, suggesting enhanced serotonin neurotransmission. Additionally, the sucrose preference test showed a trend towards increased preference in the HFD + Pita group compared to the HFD group, indicating a potential reduction in depressive-like behavior.

CONCLUSION

Our findings demonstrate that pitavastatin not only lowers cholesterol and reduces inflammation but also enhances SERT availability, suggesting a potential role in alleviating depressive symptoms associated with hypercholesterolemia. These results highlight the multifaceted benefits of pitavastatin, extending beyond its lipid-lowering effects to potentially improving mood regulation and neurotransmitter function.

Ambiguity potentiates effects of loneliness on feelings of rejection

For social species, having strong and high-quality social relationships is an important safety cue. Loneliness occurs when an individual perceives they have insufficient relationships resulting in feelings of lack of safety. States of perceived unsafety are linked to an increased tendency to construe ambiguous information - information lacking a unique clear interpretation - as threatening. Here, we explore whether the ambiguity of social cues of interpersonal rejection moderates effects of loneliness on feelings of rejection while undergoing social exclusion. Data were collected in 2021; 144 adults completed a progressive social exclusion paradigm where they were randomly assigned to be equally included, excluded, or over-included. Social exclusion/inclusion cues became more pronounced over the course of multiple rounds of a ball-tossing game (Cyberball) resulting in a scenario where ambiguity was highest in earlier rounds and decreased over time. Participants reported feelings of loneliness prior to the task and feelings of rejection throughout the task. Results demonstrated that higher loneliness predicted increased feelings of rejection regardless of exclusion condition. Notably, this positive relationship was strongest during earlier rounds when social cues were most ambiguous. These findings contribute to our understanding of how loneliness modulates social perception to enable organisms to adequately adapt to changing circumstances.

Heart-Brain Axis: A Narrative Review of the Interaction between Depression and Arrhythmia

Arrhythmias and depression are recognized as diseases of the heart and brain, respectively, and both are major health threats that often co-occur with a bidirectional causal relationship. The autonomic nervous system (ANS) serves as a crucial component of the heart-brain axis (HBA) and the pathway of interoception. Cardiac activity can influence emotional states through ascending interoceptive pathways, while psychological stress can precipitate arrhythmias via the ANS. However, the HBA and interoception frameworks are often considered overly broad, and the precise mechanisms underlying the bidirectional relationship between depression and arrhythmias remain unclear. This narrative review aims to synthesize the existing literature, focusing on the pathological mechanisms of the ANS in depression and arrhythmia while integrating other potential mechanisms to detail heart-brain interactions. In the bidirectional communication between the heart and brain, we emphasize considering various internal factors such as genes, personality traits, stress, the endocrine system, inflammation, 5-hydroxytryptamine, and behavioral factors. Current research employs multidisciplinary knowledge to elucidate heart-brain relationships, and a deeper understanding of these interactions can help optimize clinical treatment strategies. From a broader perspective, this study emphasizes the importance of considering the body as a complex, interconnected system rather than treating organs in isolation. Investigating heart-brain interactions enhance our understanding of disease pathogenesis and advances medical science, ultimately improving human quality of life.

The "Wear and Tear" of the Organism in Temporomandibular Disorders: A Pilot Study Investigating the Effects of Allostatic Load on Heart Rate Variability and Inhibitory Control

Temporomandibular disorders (TMDs) are the most common cause of non-dental chronic pain in the orofacial region and can chronically increase the activity of the allostatic systems. The allostatic overload related to these conditions causes an autonomic dysregulation, reflected by a reduction in heart rate variability (HRV). Nevertheless, chronic pain in these patients could cause more severe health consequences, such as those related to cognitive functioning. Deficits in executive control have been associated with allostatic overload and could negatively affect pain management strategies. This study aimed to investigate the effects of chronic pain on HRV and both motor and cognitive inhibition (assessed with the Go/No-Go and Stroop tasks, respectively) in a sample of 14 patients with TMD and 15 healthy controls. Consistent with our hypothesis and the previous literature, the group with TMD had a lower resting HRV, but no differences were found between the groups in inhibition. Furthermore, the results showed that the effects of HRV on cognitive inhibition can be mediated by pain intensity. Finally, a correlation between age and HRV emerged in patients with TMD but not in healthy controls.

The Role of Psychosocial Stress on Cardiovascular Disease in Women: JACC State-of-the-Art Review

Psychosocial stress can affect cardiovascular health through multiple pathways. Certain stressors, such as socioeconomic disadvantage, childhood adversity, intimate partner violence, and caregiving stress, are especially common among women. The consequences of stress begin at a young age and persist throughout the life course. This is especially true for women, among whom the burden of negative psychosocial experiences tends to be larger in young age and midlife. Menarche, pregnancy, and menopause can further exacerbate stress in vulnerable women. Not only is psychosocial adversity prevalent in women, but it could have more pronounced consequences for cardiovascular risk among women than among men. These differential effects could reside in sex differences in responses to stress, combined with women's propensity toward vasomotor reactivity, microvascular dysfunction, and inflammation. The bulk of evidence suggests that targeting stress could be an important strategy for cardiovascular risk reduction in women.

Relationship between social participation and depressive symptoms in patients with multimorbidity: the chained mediating role of cognitive function and activities of daily living

OBJECTIVE

The potential mechanisms linking social participation and depressive symptoms in Chinese individuals with multimorbidity are not yet fully understood. This study aims to explore how cognitive function and activities of daily living (ADLs) mediate the relationship between social participation and depressive symptoms in individuals with multimorbidity.

METHODS

We selected 3782 participants with multimorbidity from the 2018 China Health and Retirement Longitudinal Study. Data related to social participation, cognitive function, ADLs, and depressive symptoms were extracted. Regression and Bootstrap analyses were used to explore the sequential mediating effects of social participation, cognitive function, ADLs, and depressive symptoms.

RESULTS

(1) There was a significant correlation between social participation, cognitive function, activities of daily living, and depressive symptoms (p < 0.01). (2) Social participation directly affected depressive symptoms (β = -0.205, p < 0.05). (3) Cognitive function (β = -0.070, p < 0.01) and activities of daily living (β = -0.058, p < 0.01) played separate mediating roles in the effect of social participation on depressive symptoms. (4) Cognitive function and activities of daily living had a chain-mediated role in the relationship between social participation and depressive symptoms in patients with multimorbidity (β = -0.020, p < 0.01).

CONCLUSION

A chained mediating effect was found between cognitive function, ADLs, social participation, and depressive symptoms in patients with multimorbidity. Social participation was found to improve the cognitive function of patients with multimorbidity, which in turn enhanced their daily life activities and ultimately alleviated their depressive symptoms.

Allostatic Load and Depression Symptoms in Cancer Survivors: A National Health and Nutrition Examination Survey Study

BACKGROUND

Individuals with cancer often experience stress throughout the cancer trajectory and have a high risk of experiencing depression.

OBJECTIVE

The aim of this study was to examine the relationship between allostatic load (AL), a measure of cumulative stress-related physiologic dysregulation of different body systems, and symptoms of depression in cancer survivors.

METHODS

Participants were 294 adult cancer survivors from the US National Health and Nutrition Examination Survey (NHANES 2007-2018). Allostatic load was measured using 14 indicators representing cardiometabolic risk, glucose metabolism, cardiopulmonary functioning, parasympathetic functioning, and inflammation. Depressive symptoms were measured with the Patient Health Questionnaire-9. The relationship between AL and depressive symptoms was investigated using multiple regression adjusted for diverse sociodemographic and diagnosis variables.

RESULTS

Higher AL was associated with higher depressive symptom scores. The higher risk of depression was concentrated among those survivors in the highest AL quartile, with 21% (95% confidence interval, 11%-32%) of survivors presenting a high risk of depression compared with 8% to 11% of survivors in the lower quartiles. In exploratory analyses, the relationship between AL and depressive symptoms was only significant among survivors with a lower income. In contrast, in survivors in the highest income group, depressive symptoms were lower and unrelated to AL.

CONCLUSION

High AL is associated with more depressive symptoms among cancer survivors.

IMPLICATIONS FOR PRACTICE

Nurses have an important role in identifying psychological distress in cancer patients and survivors. Further research is needed to investigate the usefulness of AL as a marker in the context of cancer follow-up care and screening for psychological distress.

The autobiographical memory system and chronic pain: A neurocognitive framework for the initiation and maintenance of chronic pain

Chronic pain affects approximately 20% of the world's population, exerting a substantial burden on the affected individual, their families, and healthcare systems globally. Deficits in autobiographical memory have been identified among individuals living with chronic pain, and even found to pose a risk for the transition to chronicity. Recent neuroimaging studies have simultaneously implicated common brain regions central to autobiographical memory processing in the maintenance of and susceptibility to chronic pain. The present review proposes a novel neurocognitive framework for chronic pain explained by mechanisms underlying the autobiographical memory system. Here, we 1) summarize the current literature on autobiographical memory in pain, 2) discuss the role of the hippocampus and cortical brain regions including the ventromedial prefrontal cortex, anterior temporal lobe, and amygdala in relation to autobiographical memory, memory schemas, emotional processing, and pain, 3) synthesize these findings in a neurocognitive framework that explains these relationships and their implications for patients' pain outcomes, and 4) propose translational directions for the prevention, management, and treatment of chronic pain.

Brain RFamide Neuropeptides in Stress-Related Psychopathologies

The RFamide peptide family is a group of proteins that share a common C-terminal arginine-phenylalanine-amide motif. To date, the family comprises five groups in mammals: neuropeptide FF, LPXRFamides/RFamide-related peptides, prolactin releasing peptide, QRFP, and kisspeptins. Different RFamide peptides have their own cognate receptors and are produced by different cell populations, although they all can also bind to neuropeptide FF receptors with different affinities. RFamide peptides function in the brain as neuropeptides regulating key aspects of homeostasis such as energy balance, reproduction, and cardiovascular function. Furthermore, they are involved in the organization of the stress response including modulation of pain. Considering the interaction between stress and various parameters of homeostasis, the role of RFamide peptides may be critical in the development of stress-related neuropathologies. This review will therefore focus on the role of RFamide peptides as possible key hubs in stress and stress-related psychopathologies. The neurotransmitter coexpression profile of RFamide-producing cells is also discussed, highlighting its potential functional significance. The development of novel pharmaceutical agents for the treatment of stress-related disorders is an ongoing need. Thus, the importance of RFamide research is underlined by the emergence of peptidergic and G-protein coupled receptor-based therapeutic targets in the pharmaceutical industry.

The association between parenthood and health: A comparison of people in same-sex and different-sex relationships

Understanding social inequalities in parental health is crucial for family functioning and child development. Theoretically, the double burden of parenting and minority stress may lead to the negative association between parenthood and health outcomes being stronger for people in same-sex relationships. Moreover, drawn from the social control process and the compensation mechanism, the negative association between parenthood and health risk behaviors may become stronger for people in same-sex relationships. Yet, empirical evidence on parental health disparities between parents in same- and different-sex relationships is limited. Using linear and logistic regression models, coarsened exact matching, and entropy balancing on Dutch data between 2008 and 2021 (196 people in same-sex relationships and 6948 people in different-sex relationships), we investigate the relationship between parenthood and three health outcomes (self-rated health, physical health, and mental health) and two health risk behaviors (smoking and heavy episodic drinking). We find that parents on average are less likely to experience heavy episodic drinking than non-parents. The association between parenthood and health does not differ between people in same-sex and different-sex relationships.

Unpredictable chronic mild stress shows neuronal remodeling in multipolar projection neurons of hippocampal complex in postnatal chicks

The hippocampal complex of birds is a narrow-curved strip of tissue that plays a crucial role in learning, memory, spatial navigation, and emotional and sexual behavior. This study was conducted to evaluate the effect of unpredictable chronic mild stress in multipolar neurons of 3-, 5-, 7-, and 9-week-old chick's hippocampal complex. This study revealed that chronic stress results in neuronal remodeling by causing alterations in dendritic field, axonal length, secondary branching, corrected spine number, and dendritic branching at 25, 50, 75, and 100 µm. Due to stress, the overall dendritic length was significantly retracted in 3-week-old chick, whereas no significant difference was observed in 5- and 7-week-old chick, but again it was significantly retracted in 9-week-old chick along with the axonal length. So, this study indicates that during initial days of stress exposure, the dendritic field shows retraction, but when the stress continues up to a certain level, the neurons undergo structural modifications so that chicks adapt and survive in stressful conditions. The repeated exposure to chronic stress for longer duration leads to the neuronal structural disruption by retraction in the dendritic length as well as axonal length. Another characteristic which leads to structural alterations is the dendritic spines which significantly decreased in all age groups of stressed chicks and eventually leads to less synaptic connections, disturbance in physiology, and neurology, which affects the learning, memory, and coping ability of an individual.

Molecular signatures of astrocytes and microglia maladaptive responses to acute stress are rescued by a single administration of ketamine in a rodent model of PTSD

Stress affects the brain and alters its neuroarchitecture and function; these changes can be severe and lead to psychiatric disorders. Recent evidence suggests that astrocytes and microglia play an essential role in the stress response by contributing to the maintenance of cerebral homeostasis. These cells respond rapidly to all stimuli that reach the brain, including stressors. Here, we used a recently validated rodent model of post-traumatic stress disorder in which rats can be categorized as resilient or vulnerable after acute inescapable footshock stress. We then investigated the functional, molecular, and morphological determinants of stress resilience and vulnerability in the prefrontal cortex, focusing on glial and neuronal cells. In addition, we examined the effects of a single subanesthetic dose of ketamine, a fast-acting antidepressant recently approved for the treatment of resistant depression and proposed for other stress-related psychiatric disorders. The present results suggest a prompt glial cell response and activation of the NF-κB pathway after acute stress, leading to an increase in specific cytokines such as IL-18 and TNF-α. This response persists in vulnerable individuals and is accompanied by a significant change in the levels of critical glial proteins such as S100B, CD11b, and CX43, brain trophic factors such as BDNF and FGF2, and proteins related to dendritic arborization and synaptic architecture such as MAP2 and PSD95. Administration of ketamine 24 h after the acute stress event rescued many of the changes observed in vulnerable rats, possibly contributing to support brain homeostasis. Overall, our results suggest that pivotal events, including reactive astrogliosis, changes in brain trophic factors, and neuronal damage are critical determinants of vulnerability to acute traumatic stress and confirm the therapeutic effect of acute ketamine against the development of stress-related psychiatric disorders.

Septohippocampal cholinergic system at the intersection of stress and cognition: Current trends and translational implications

Deficits in hippocampus-dependent memory processes are common across psychiatric and neurodegenerative disorders such as depression, anxiety and Alzheimer's disease. Moreover, stress is a major environmental risk factor for these pathologies and it exerts detrimental effects on hippocampal functioning via the activation of hypothalamic-pituitary-adrenal (HPA) axis. The medial septum cholinergic neurons extensively innervate the hippocampus. Although, the cholinergic septohippocampal pathway (SHP) has long been implicated in learning and memory, its involvement in mediating the adaptive and maladaptive impact of stress on mnemonic processes remains less clear. Here, we discuss current research highlighting the contributions of cholinergic SHP in modulating memory encoding, consolidation and retrieval. Then, we present evidence supporting the view that neurobiological interactions between HPA axis stress response and cholinergic signalling impact hippocampal computations. Finally, we critically discuss potential challenges and opportunities to target cholinergic SHP as a therapeutic strategy to improve cognitive impairments in stress-related disorders. We argue that such efforts should consider recent conceptualisations on the dynamic nature of cholinergic signalling in modulating distinct subcomponents of memory and its interactions with cellular substrates that regulate the adaptive stress response.

Mind-body practices in chronic inflammatory arthritis

Mind-body practices are complementary approaches recognized by the World Health Organization (WHO). While these practices are very diverse, they all focus on the interaction between mind and body. These include mindful meditation, yoga, Tai Chi, sophrology, hypnosis and various relaxation techniques. There is growing interest in incorporating these strategies in the management of chronic rheumatic diseases including rheumatoid arthritis. The aim of this review is to describe the main mind-body practices and analyze the existing evidence in chronic rheumatic diseases. In rheumatoid arthritis, the Mindfulness-Based Stress Reduction program, yoga, Tai Chi and relaxation may improve patient-reported outcomes, but the benefit on inflammation and structural progression is unclear. In spondyloarthritis, very few studies are available but similar evidence exist. Further evaluations of these practices in chronic rheumatic diseases are needed since their risk/benefit ratio appears excellent.

Statistical Genetic Approaches to Investigate Genotype-by-Environment Interaction: Review and Novel Extension of Models

Statistical genetic models of genotype-by-environment (G×E) interaction can be divided into two general classes, one on G×E interaction in response to dichotomous environments (e.g., sex, disease-affection status, or presence/absence of an exposure) and the other in response to continuous environments (e.g., physical activity, nutritional measurements, or continuous socioeconomic measures). Here we develop a novel model to jointly account for dichotomous and continuous environments. We develop the model in terms of a joint genotype-by-sex (for the dichotomous environment) and genotype-by-social determinants of health (SDoH; for the continuous environment). Using this model, we show how a depression variable, as measured by the Beck Depression Inventory-II survey instrument, is not only underlain by genetic effects (as has been reported elsewhere) but is also significantly determined by joint G×Sex and G×SDoH interaction effects. This model has numerous applications leading to potentially transformative research on the genetic and environmental determinants underlying complex diseases.

Allostatic Load in Childhood, Adolescence, and Young Adulthood: Are Assumptions of Measurement Invariance Warranted?

OVERVIEW

Allostatic load represents the cumulative toll of chronic mobilization of the body's stress response systems, as indexed by biomarkers. Higher levels of stress and disadvantage predict higher levels of allostatic load, which, in turn, predict poorer physical and mental health outcomes. To maximize the efficacy of prevention efforts, screening for stress- and disadvantage-associated health conditions must occur before middle age-that is, during childhood, adolescence, and young adulthood. However, this requires that models of allostatic load display properties of measurement invariance across age groups. Because most research on allostatic load has featured older adults, it is unclear if these requirements can be met.

METHODS

To address this question, we fit a series of exploratory and confirmatory analytic models to data on eight biomarkers using a nationally representative sample of N = 4260 children, adolescents, and young adults drawn from the National Health and Nutrition Examination Survey dataset.

RESULTS

Exploratory and confirmatory models indicated that, consistent with allostatic load theory, a unidimensional model was a good fit to the data. However, this model did not display properties of measurement invariance; post-hoc analyses suggested that the biomarkers included in the final confirmatory model were most strongly intercorrelated among young adults and most weakly intercorrelated among adolescents.

CONCLUSIONS

These results underscore the importance of testing assumptions about measurement invariance in allostatic load before drawing substantive conclusions about stress, disadvantage, and health by directly comparing levels of allostatic load across different stages of development, while underscoring the need to expand investigations of measurement invariance to samples of longitudinal data.

Relationship of sleep with diurnal cortisol rhythm considering sleep measurement and cortisol sampling schemes

Information on the relationships between the previous night's sleep and the next-day diurnal cortisol rhythm is inconsistent due to confounding factors such as sleep measurements (trait/state sleep and objective/subjective sleep) and cortisol sampling schemes. Therefore, this study aimed to investigate these relationships, considering the confounding factors. College students (n = 79) wore actigraphy for 3 days to undergo an evaluation of previous night-time sleep objectively and reported their subjective sleep parameters in a sleep diary. In addition, participants provided six salivary cortisol samples daily. Furthermore, six cortisol sampling schemes were created to reflect diurnal cortisol rhythms, and two different methods were used to calculate the index of diurnal cortisol slope (DCS). A multilevel model was created to examine the impact of both trait and state sleep on next-day diurnal cortisol rhythm. The results revealed that higher objective state sleep efficiency and longer objective state total sleep time were associated with a higher cortisol awakening response (CAR). Moreover, higher objective trait sleep efficiency and longer objective trait total sleep time were associated with higher waking cortisol levels and steeper DCS. In addition, a minimum of four saliva samples were required at different time points, including upon waking, 30 min after waking, 1 h after waking, and at bedtime, to explore the relationship of sleep efficiency/total sleep time with waking cortisol, CAR, and DCS. Furthermore, the index of the peak-to-bed slope was appropriately employed to examine the relationship between sleep efficiency and DCS, whereas the wake-to-bed slope was effective for examining the relationship between total sleep time and DCS. In summary, this study clarified the relationship between sleep and next-day diurnal cortisol rhythm and suggested a cost-effective cortisol sampling schedule and calculation methods.

Ethics of Nudging in the COVID-19 Crisis and the Necessary Return to the Principles of Shared Decision Making: A Critical Review

Nudging, a controversial technique for modifying people's behavior in a predictable way, is claimed to preserve freedom of choice while simultaneously influencing it. Nudging had been largely confined to situations such as promoting healthy eating choices but has been employed in the coronavirus disease 2019 (COVID-19) crisis in a shift towards measures that involve significantly less choice, such as shoves and behavioral prods. Shared decision making (SDM), a method for direct involvement and autonomy, is an alternative approach to communicate risk. Predominantly peer-reviewed scientific publications from standard literature databases like PubMed, PsycInfo, and Psyndex were evaluated in a narrative review. The so-called fear nudges, as well as the dissemination of strongly emotionalizing or moralizing messages can lead to intense psycho-physical stress. The use of these nudges by specialized units during the COVID-19 pandemic generated a societal atmosphere of fear that precipitated a deterioration of the mental and physical health of the population. Major recommendations of the German COVID-19 Snapshot Monitoring (COSMO) study, which are based on elements of nudging and coercive measures, do not comply with ethical principles, basic psychological principles, or evidence-based data. SDM was misused in the COVID-19 crisis, which helped to achieve one-sided goals of governments. The emphasis on utilitarian thinking is criticized and the unethical behavior of decision makers is explained by both using the concept of moral disengagement and the maturity level of coping strategies. There should be a return to an open-ended, democratic, and pluralistic scientific debate without using nudges. It is therefore necessary to return to the origins of SDM.